text: /*
  Copyright (c) 2012 Sencha Inc. - Author: Nicolas Garcia Belmonte (http://philogb.github.com/)
  
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
  
  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
  
   */
   (function () { 
  
  /*
    File: Core.js
  
   */
  
  /*
   Object: $jit
   
   Defines the namespace for all library Classes and Objects. 
   This variable is the *only* global variable defined in the Toolkit. 
   There are also other interesting properties attached to this variable described below.
   */
  this.$jit = function(w) {
    w = w || window;
    for(var k in $jit) {
      if($jit[k].$extend) {
        w[k] = $jit[k];
      }
    }
  };
  
  $jit.version = '2.0.1';
  /*
    Object: $jit.id
    
    Works just like *document.getElementById*
    
    Example:
    (start code js)
    var element = $jit.id('elementId');
    (end code)
  
  */
  
  /*
   Object: $jit.util
   
   Contains utility functions.
   
   Some of the utility functions and the Class system were based in the MooTools Framework 
   <http://mootools.net>. Copyright (c) 2006-2010 Valerio Proietti, <http://mad4milk.net/>. 
   MIT license <http://mootools.net/license.txt>.
   
   These methods are generally also implemented in DOM manipulation frameworks like JQuery, MooTools and Prototype.
   I'd suggest you to use the functions from those libraries instead of using these, since their functions 
   are widely used and tested in many different platforms/browsers. Use these functions only if you have to.
   
   */
  var $ = function(d) {
    return document.getElementById(d);
  };
  
  $.empty = function() {
  };
  
  /*
    Method: extend
    
    Augment an object by appending another object's properties.
    
    Parameters:
    
    original - (object) The object to be extended.
    extended - (object) An object which properties are going to be appended to the original object.
    
    Example:
    (start code js)
    $jit.util.extend({ 'a': 1, 'b': 2 }, { 'b': 3, 'c': 4 }); //{ 'a':1, 'b': 3, 'c': 4 }
    (end code)
  */
  $.extend = function(original, extended) {
    for ( var key in (extended || {}))
      original[key] = extended[key];
    return original;
  };
  
  $.lambda = function(value) {
    return (typeof value == 'function') ? value : function() {
      return value;
    };
  };
  
  $.time = Date.now || function() {
    return +new Date;
  };
  
  /*
    Method: splat
    
    Returns an array wrapping *obj* if *obj* is not an array. Returns *obj* otherwise.
    
    Parameters:
    
    obj - (mixed) The object to be wrapped in an array.
    
    Example:
    (start code js)
    $jit.util.splat(3);   //[3]
    $jit.util.splat([3]); //[3]
    (end code)
  */
  $.splat = function(obj) {
    var type = $.type(obj);
    return type ? ((type != 'array') ? [ obj ] : obj) : [];
  };
  
  $.type = function(elem) {
    var type = $.type.s.call(elem).match(/^\[object\s(.*)\]$/)[1].toLowerCase();
    if(type != 'object') return type;
    if(elem && elem.$$family) return elem.$$family;
    return (elem && elem.nodeName && elem.nodeType == 1)? 'element' : type;
  };
  $.type.s = Object.prototype.toString;
  
  /*
    Method: each
    
    Iterates through an iterable applying *f*.
    
    Parameters:
    
    iterable - (array) The original array.
    fn - (function) The function to apply to the array elements.
    
    Example:
    (start code js)
    $jit.util.each([3, 4, 5], function(n) { alert('number ' + n); });
    (end code)
  */
  $.each = function(iterable, fn) {
    var type = $.type(iterable);
    if (type == 'object') {
      for ( var key in iterable)
        fn(iterable[key], key);
    } else {
      for ( var i = 0, l = iterable.length; i < l; i++)
        fn(iterable[i], i);
    }
  };
  
  $.indexOf = function(array, item) {
    if(Array.indexOf) return array.indexOf(item);
    for(var i=0,l=array.length; i<l; i++) {
      if(array[i] === item) return i;
    }
    return -1;
  };
  
  /*
    Method: map
    
    Maps or collects an array by applying *f*.
    
    Parameters:
    
    array - (array) The original array.
    f - (function) The function to apply to the array elements.
    
    Example:
    (start code js)
    $jit.util.map([3, 4, 5], function(n) { return n*n; }); //[9, 16, 25]
    (end code)
  */
  $.map = function(array, f) {
    var ans = [];
    $.each(array, function(elem, i) {
      ans.push(f(elem, i));
    });
    return ans;
  };
  
  /*
    Method: reduce
    
    Iteratively applies the binary function *f* storing the result in an accumulator.
    
    Parameters:
    
    array - (array) The original array.
    f - (function) The function to apply to the array elements.
    opt - (optional|mixed) The starting value for the acumulator.
    
    Example:
    (start code js)
    $jit.util.reduce([3, 4, 5], function(x, y) { return x + y; }, 0); //12
    (end code)
  */
  $.reduce = function(array, f, opt) {
    var l = array.length;
    if(l==0) return opt;
    var acum = arguments.length == 3? opt : array[--l];
    while(l--) {
      acum = f(acum, array[l]);
    }
    return acum;
  };
  
  /*
    Method: merge
    
    Merges n-objects and their sub-objects creating a new, fresh object.
    
    Parameters:
    
    An arbitrary number of objects.
    
    Example:
    (start code js)
    $jit.util.merge({ 'a': 1, 'b': 2 }, { 'b': 3, 'c': 4 }); //{ 'a':1, 'b': 3, 'c': 4 }
    (end code)
  */
  $.merge = function() {
    var mix = {};
    for ( var i = 0, l = arguments.length; i < l; i++) {
      var object = arguments[i];
      if ($.type(object) != 'object')
        continue;
      for ( var key in object) {
        var op = object[key], mp = mix[key];
        mix[key] = (mp && $.type(op) == 'object' && $.type(mp) == 'object') ? $
            .merge(mp, op) : $.unlink(op);
      }
    }
    return mix;
  };
  
  $.unlink = function(object) {
    var unlinked;
    switch ($.type(object)) {
    case 'object':
      unlinked = {};
      for ( var p in object)
        unlinked[p] = $.unlink(object[p]);
      break;
    case 'array':
      unlinked = [];
      for ( var i = 0, l = object.length; i < l; i++)
        unlinked[i] = $.unlink(object[i]);
      break;
    default:
      return object;
    }
    return unlinked;
  };
  
  $.zip = function() {
    if(arguments.length === 0) return [];
    for(var j=0, ans=[], l=arguments.length, ml=arguments[0].length; j<ml; j++) {
      for(var i=0, row=[]; i<l; i++) {
        row.push(arguments[i][j]);
      }
      ans.push(row);
    }
    return ans;
  };
  
  /*
    Method: rgbToHex
    
    Converts an RGB array into a Hex string.
    
    Parameters:
    
    srcArray - (array) An array with R, G and B values
    
    Example:
    (start code js)
    $jit.util.rgbToHex([255, 255, 255]); //'#ffffff'
    (end code)
  */
  $.rgbToHex = function(srcArray, array) {
    if (srcArray.length < 3)
      return null;
    if (srcArray.length == 4 && srcArray[3] == 0 && !array)
      return 'transparent';
    var hex = [];
    for ( var i = 0; i < 3; i++) {
      var bit = (srcArray[i] - 0).toString(16);
      hex.push(bit.length == 1 ? '0' + bit : bit);
    }
    return array ? hex : '#' + hex.join('');
  };
  
  /*
    Method: hexToRgb
    
    Converts an Hex color string into an RGB array.
    
    Parameters:
    
    hex - (string) A color hex string.
    
    Example:
    (start code js)
    $jit.util.hexToRgb('#fff'); //[255, 255, 255]
    (end code)
  */
  $.hexToRgb = function(hex) {
    if (hex.length != 7) {
      hex = hex.match(/^#?(\w{1,2})(\w{1,2})(\w{1,2})$/);
      hex.shift();
      if (hex.length != 3)
        return null;
      var rgb = [];
      for ( var i = 0; i < 3; i++) {
        var value = hex[i];
        if (value.length == 1)
          value += value;
        rgb.push(parseInt(value, 16));
      }
      return rgb;
    } else {
      hex = parseInt(hex.slice(1), 16);
      return [ hex >> 16, hex >> 8 & 0xff, hex & 0xff ];
    }
  };
  
  $.destroy = function(elem) {
    $.clean(elem);
    if (elem.parentNode)
      elem.parentNode.removeChild(elem);
    if (elem.clearAttributes)
      elem.clearAttributes();
  };
  
  $.clean = function(elem) {
    for (var ch = elem.childNodes, i = 0, l = ch.length; i < l; i++) {
      $.destroy(ch[i]);
    }
  };
  
  /*
    Method: addEvent
    
    Cross-browser add event listener.
    
    Parameters:
    
    obj - (obj) The Element to attach the listener to.
    type - (string) The listener type. For example 'click', or 'mousemove'.
    fn - (function) The callback function to be used when the event is fired.
    
    Example:
    (start code js)
    $jit.util.addEvent(elem, 'click', function(){ alert('hello'); });
    (end code)
  */
  $.addEvent = function(obj, type, fn) {
    if (obj.addEventListener)
      obj.addEventListener(type, fn, false);
    else
      obj.attachEvent('on' + type, fn);
  };
  
  $.addEvents = function(obj, typeObj) {
    for(var type in typeObj) {
      $.addEvent(obj, type, typeObj[type]);
    }
  };
  
  $.hasClass = function(obj, klass) {
    return (' ' + obj.className + ' ').indexOf(' ' + klass + ' ') > -1;
  };
  
  $.addClass = function(obj, klass) {
    if (!$.hasClass(obj, klass))
      obj.className = (obj.className + " " + klass);
  };
  
  $.removeClass = function(obj, klass) {
    obj.className = obj.className.replace(new RegExp(
        '(^|\\s)' + klass + '(?:\\s|$)'), '$1');
  };
  
  $.getPos = function(elem) {
    var offset = getOffsets(elem);
    var scroll = getScrolls(elem);
    return {
      x: offset.x - scroll.x,
      y: offset.y - scroll.y
    };
  
    function getOffsets(elem) {
      var position = {
        x: 0,
        y: 0
      };
      while (elem && !isBody(elem)) {
        position.x += elem.offsetLeft;
        position.y += elem.offsetTop;
        elem = elem.offsetParent;
      }
      return position;
    }
  
    function getScrolls(elem) {
      var position = {
        x: 0,
        y: 0
      };
      while (elem && !isBody(elem)) {
        position.x += elem.scrollLeft;
        position.y += elem.scrollTop;
        elem = elem.parentNode;
      }
      return position;
    }
  
    function isBody(element) {
      return (/^(?:body|html)$/i).test(element.tagName);
    }
  };
  
  $.event = {
    get: function(e, win) {
      win = win || window;
      return e || win.event;
    },
    getWheel: function(e) {
      return e.wheelDelta? e.wheelDelta / 120 : -(e.detail || 0) / 3;
    },
    isRightClick: function(e) {
      return (e.which == 3 || e.button == 2);
    },
    getPos: function(e, win) {
      // get mouse position
      win = win || window;
      e = e || win.event;
      var doc = win.document;
      doc = doc.documentElement || doc.body;
      //TODO(nico): make touch event handling better
      if(e.touches && e.touches.length) {
        e = e.touches[0];
      }
      var page = {
        x: e.pageX || (e.clientX + doc.scrollLeft),
        y: e.pageY || (e.clientY + doc.scrollTop)
      };
      return page;
    },
    stop: function(e) {
      if (e.stopPropagation) e.stopPropagation();
      e.cancelBubble = true;
      if (e.preventDefault) e.preventDefault();
      else e.returnValue = false;
    }
  };
  
  $jit.util = $jit.id = $;
  
  var Class = function(properties) {
    properties = properties || {};
    var klass = function() {
      for ( var key in this) {
        if (typeof this[key] != 'function')
          this[key] = $.unlink(this[key]);
      }
      this.constructor = klass;
      if (Class.prototyping)
        return this;
      var instance = this.initialize ? this.initialize.apply(this, arguments)
          : this;
      //typize
      this.$$family = 'class';
      return instance;
    };
  
    for ( var mutator in Class.Mutators) {
      if (!properties[mutator])
        continue;
      properties = Class.Mutators[mutator](properties, properties[mutator]);
      delete properties[mutator];
    }
  
    $.extend(klass, this);
    klass.constructor = Class;
    klass.prototype = properties;
    return klass;
  };
  
  Class.Mutators = {
  
    Implements: function(self, klasses) {
      $.each($.splat(klasses), function(klass) {
        Class.prototyping = klass;
        var instance = (typeof klass == 'function') ? new klass : klass;
        for ( var prop in instance) {
          if (!(prop in self)) {
            self[prop] = instance[prop];
          }
        }
        delete Class.prototyping;
      });
      return self;
    }
  
  };
  
  $.extend(Class, {
  
    inherit: function(object, properties) {
      for ( var key in properties) {
        var override = properties[key];
        var previous = object[key];
        var type = $.type(override);
        if (previous && type == 'function') {
          if (override != previous) {
            Class.override(object, key, override);
          }
        } else if (type == 'object') {
          object[key] = $.merge(previous, override);
        } else {
          object[key] = override;
        }
      }
      return object;
    },
  
    override: function(object, name, method) {
      var parent = Class.prototyping;
      if (parent && object[name] != parent[name])
        parent = null;
      var override = function() {
        var previous = this.parent;
        this.parent = parent ? parent[name] : object[name];
        var value = method.apply(this, arguments);
        this.parent = previous;
        return value;
      };
      object[name] = override;
    }
  
  });
  
  Class.prototype.implement = function() {
    var proto = this.prototype;
    $.each(Array.prototype.slice.call(arguments || []), function(properties) {
      Class.inherit(proto, properties);
    });
    return this;
  };
  
  $jit.Class = Class;
  
  /*
    Object: $jit.json
    
    Provides JSON utility functions.
    
    Most of these functions are JSON-tree traversal and manipulation functions.
  */
  $jit.json = {
    /*
       Method: prune
    
       Clears all tree nodes having depth greater than maxLevel.
    
       Parameters:
    
          tree - (object) A JSON tree object. For more information please see <Loader.loadJSON>.
          maxLevel - (number) An integer specifying the maximum level allowed for this tree. All nodes having depth greater than max level will be deleted.
  
    */
    prune: function(tree, maxLevel) {
      this.each(tree, function(elem, i) {
        if (i == maxLevel && elem.children) {
          delete elem.children;
          elem.children = [];
        }
      });
    },
    /*
       Method: getParent
    
       Returns the parent node of the node having _id_ as id.
    
       Parameters:
    
          tree - (object) A JSON tree object. See also <Loader.loadJSON>.
          id - (string) The _id_ of the child node whose parent will be returned.
  
      Returns:
  
          A tree JSON node if any, or false otherwise.
    
    */
    getParent: function(tree, id) {
      if (tree.id == id)
        return false;
      var ch = tree.children;
      if (ch && ch.length > 0) {
        for ( var i = 0; i < ch.length; i++) {
          if (ch[i].id == id)
            return tree;
          else {
            var ans = this.getParent(ch[i], id);
            if (ans)
              return ans;
          }
        }
      }
      return false;
    },
    /*
       Method: getSubtree
    
       Returns the subtree that matches the given id.
    
       Parameters:
    
          tree - (object) A JSON tree object. See also <Loader.loadJSON>.
          id - (string) A node *unique* identifier.
    
       Returns:
    
          A subtree having a root node matching the given id. Returns null if no subtree matching the id is found.
  
    */
    getSubtree: function(tree, id) {
      if (tree.id == id)
        return tree;
      for ( var i = 0, ch = tree.children; ch && i < ch.length; i++) {
        var t = this.getSubtree(ch[i], id);
        if (t != null)
          return t;
      }
      return null;
    },
    /*
       Method: eachLevel
    
        Iterates on tree nodes with relative depth less or equal than a specified level.
    
       Parameters:
    
          tree - (object) A JSON tree or subtree. See also <Loader.loadJSON>.
          initLevel - (number) An integer specifying the initial relative level. Usually zero.
          toLevel - (number) An integer specifying a top level. This method will iterate only through nodes with depth less than or equal this number.
          action - (function) A function that receives a node and an integer specifying the actual level of the node.
            
      Example:
     (start code js)
       $jit.json.eachLevel(tree, 0, 3, function(node, depth) {
          alert(node.name + ' ' + depth);
       });
     (end code)
    */
    eachLevel: function(tree, initLevel, toLevel, action) {
      if (initLevel <= toLevel) {
        action(tree, initLevel);
        if(!tree.children) return;
        for ( var i = 0, ch = tree.children; i < ch.length; i++) {
          this.eachLevel(ch[i], initLevel + 1, toLevel, action);
        }
      }
    },
    /*
       Method: each
    
        A JSON tree iterator.
    
       Parameters:
    
          tree - (object) A JSON tree or subtree. See also <Loader.loadJSON>.
          action - (function) A function that receives a node.
  
      Example:
      (start code js)
        $jit.json.each(tree, function(node) {
          alert(node.name);
        });
      (end code)
            
    */
    each: function(tree, action) {
      this.eachLevel(tree, 0, Number.MAX_VALUE, action);
    }
  };
  
  
  /*
   * File: Canvas.js
   *
   */
  
  /*
   Class: Canvas
   
   	A canvas widget used by all visualizations. The canvas object can be accessed by doing *viz.canvas*. If you want to 
   	know more about <Canvas> options take a look at <Options.Canvas>.
   
   A canvas widget is a set of DOM elements that wrap the native canvas DOM Element providing a consistent API and behavior 
   across all browsers. It can also include Elements to add DOM (SVG or HTML) label support to all visualizations.
   
   Example:
   
   Suppose we have this HTML
   
   (start code xml)
   	<div id="infovis"></div>
   (end code)
   
   Now we create a new Visualization
   
   (start code js)
   	var viz = new $jit.Viz({
   		//Where to inject the canvas. Any div container will do.
   		'injectInto':'infovis',
  		 //width and height for canvas. 
  		 //Default's to the container offsetWidth and Height.
  		 'width': 900,
  		 'height':500
  	 });
   (end code)
  
   The generated HTML will look like this
   
   (start code xml)
   <div id="infovis">
   	<div id="infovis-canvaswidget" style="position:relative;">
   	<canvas id="infovis-canvas" width=900 height=500
   	style="position:absolute; top:0; left:0; width:900px; height:500px;" />
   	<div id="infovis-label"
   	style="overflow:visible; position:absolute; top:0; left:0; width:900px; height:0px">
   	</div>
   	</div>
   </div>
   (end code)
   
   As you can see, the generated HTML consists of a canvas DOM Element of id *infovis-canvas* and a div label container
   of id *infovis-label*, wrapped in a main div container of id *infovis-canvaswidget*.
   */
  
  var Canvas;
  (function() {
    //check for native canvas support
    var canvasType = typeof HTMLCanvasElement,
        supportsCanvas = (canvasType == 'object' || canvasType == 'function');
    //create element function
    function $E(tag, props) {
      var elem = document.createElement(tag);
      for(var p in props) {
        if(typeof props[p] == "object") {
          $.extend(elem[p], props[p]);
        } else {
          elem[p] = props[p];
        }
      }
      if (tag == "canvas" && !supportsCanvas && G_vmlCanvasManager) {
        elem = G_vmlCanvasManager.initElement(document.body.appendChild(elem));
      }
      return elem;
    }
    //canvas widget which we will call just Canvas
    $jit.Canvas = Canvas = new Class({
      canvases: [],
      pos: false,
      element: false,
      labelContainer: false,
      translateOffsetX: 0,
      translateOffsetY: 0,
      scaleOffsetX: 1,
      scaleOffsetY: 1,
      
      initialize: function(viz, opt) {
        this.viz = viz;
        this.opt = this.config = opt;
        var id = $.type(opt.injectInto) == 'string'? 
            opt.injectInto:opt.injectInto.id,
            type = opt.type,
            idLabel = id + "-label", 
            wrapper = $(id),
            width = opt.width || wrapper.offsetWidth,
            height = opt.height || wrapper.offsetHeight;
        this.id = id;
        //canvas options
        var canvasOptions = {
          injectInto: id,
          width: width,
          height: height
        };
        //create main wrapper
        this.element = $E('div', {
          'id': id + '-canvaswidget',
          'style': {
            'position': 'relative',
            'width': width + 'px',
            'height': height + 'px'
          }
        });
        //create label container
        this.labelContainer = this.createLabelContainer(opt.Label.type, 
            idLabel, canvasOptions);
        //create primary canvas
        this.canvases.push(new Canvas.Base[type]({
          config: $.extend({idSuffix: '-canvas'}, canvasOptions),
          plot: function(base) {
            viz.fx.plot();
          },
          resize: function() {
            viz.refresh();
          }
        }));
        //create secondary canvas
        var back = opt.background;
        if(back) {
          var backCanvas = new Canvas.Background[back.type](viz, $.extend(back, canvasOptions));
          this.canvases.push(new Canvas.Base[type](backCanvas));
        }
        //insert canvases
        var len = this.canvases.length;
        while(len--) {
          this.element.appendChild(this.canvases[len].canvas);
          if(len > 0) {
            this.canvases[len].plot();
          }
        }
        this.element.appendChild(this.labelContainer);
        wrapper.appendChild(this.element);
        //Update canvas position when the page is scrolled.
        var timer = null, that = this;
        $.addEvent(window, 'scroll', function() {
          clearTimeout(timer);
          timer = setTimeout(function() {
            that.getPos(true); //update canvas position
          }, 500);
        });
      },
      /*
        Method: getCtx
        
        Returns the main canvas context object
        
        Example:
        
        (start code js)
         var ctx = canvas.getCtx();
         //Now I can use the native canvas context
         //and for example change some canvas styles
         ctx.globalAlpha = 1;
        (end code)
      */
      getCtx: function(i) {
        return this.canvases[i || 0].getCtx();
      },
      /*
        Method: getConfig
        
        Returns the current Configuration for this Canvas Widget.
        
        Example:
        
        (start code js)
         var config = canvas.getConfig();
        (end code)
      */
      getConfig: function() {
        return this.opt;
      },
      /*
        Method: getElement
  
        Returns the main Canvas DOM wrapper
        
        Example:
        
        (start code js)
         var wrapper = canvas.getElement();
         //Returns <div id="infovis-canvaswidget" ... >...</div> as element
        (end code)
      */
      getElement: function() {
        return this.element;
      },
      /*
        Method: getSize
        
        Returns canvas dimensions.
        
        Returns:
        
        An object with *width* and *height* properties.
        
        Example:
        (start code js)
        canvas.getSize(); //returns { width: 900, height: 500 }
        (end code)
      */
      getSize: function(i) {
        return this.canvases[i || 0].getSize();
      },
      /*
        Method: resize
        
        Resizes the canvas.
        
        Parameters:
        
        width - New canvas width.
        height - New canvas height.
        
        Example:
        
        (start code js)
         canvas.resize(width, height);
        (end code)
      
      */
      resize: function(width, height) {
        this.getPos(true);
        this.translateOffsetX = this.translateOffsetY = 0;
        this.scaleOffsetX = this.scaleOffsetY = 1;
        for(var i=0, l=this.canvases.length; i<l; i++) {
          this.canvases[i].resize(width, height);
        }
        var style = this.element.style;
        style.width = width + 'px';
        style.height = height + 'px';
        if(this.labelContainer)
          this.labelContainer.style.width = width + 'px';
      },
      /*
        Method: translate
        
        Applies a translation to the canvas.
        
        Parameters:
        
        x - (number) x offset.
        y - (number) y offset.
        disablePlot - (boolean) Default's *false*. Set this to *true* if you don't want to refresh the visualization.
        
        Example:
        
        (start code js)
         canvas.translate(30, 30);
        (end code)
      
      */
      translate: function(x, y, disablePlot) {
        this.translateOffsetX += x*this.scaleOffsetX;
        this.translateOffsetY += y*this.scaleOffsetY;
        for(var i=0, l=this.canvases.length; i<l; i++) {
          this.canvases[i].translate(x, y, disablePlot);
        }
      },
      /*
        Method: scale
        
        Scales the canvas.
        
        Parameters:
        
        x - (number) scale value.
        y - (number) scale value.
        disablePlot - (boolean) Default's *false*. Set this to *true* if you don't want to refresh the visualization.
        
        Example:
        
        (start code js)
         canvas.scale(0.5, 0.5);
        (end code)
      
      */
      scale: function(x, y, disablePlot) {
        var px = this.scaleOffsetX * x,
            py = this.scaleOffsetY * y;
        var dx = this.translateOffsetX * (x -1) / px,
            dy = this.translateOffsetY * (y -1) / py;
        this.scaleOffsetX = px;
        this.scaleOffsetY = py;
        for(var i=0, l=this.canvases.length; i<l; i++) {
          this.canvases[i].scale(x, y, true);
        }
        this.translate(dx, dy, false);
      },
      /*
        Method: getZoom
  
        Returns canvas zooming factors. *1* means initial zoom.
  
        Returns:
  
        An object with *x* and *y* properties.
      */
      getZoom: function() {
        return new Complex(this.scaleOffsetX, this.scaleOffsetY);
      },
      /*
        Method: setZoom
  
        Sets the zoom to given factors. *1* means initial zoom.
  
        Parameters:
  
        x - (number) zooming factor
        y - (number) zooming factor
        disablePlot - (boolean) Default's *false*. Set this to *true* if you don't want to refresh the visualization.
  
        Example:
        (start code js)
        canvas.setZoom(2, 2); //sets 2x zoom
        (end code)
      */
      setZoom: function(x, y, disablePlot) {
        var cur = this.getZoom(),
            px = x / cur.x,
            py = y / cur.y;
        this.scale(px, py, disablePlot);
      },
      /*
        Method: getPos
        
        Returns the canvas position as an *x, y* object.
        
        Parameters:
        
        force - (boolean) Default's *false*. Set this to *true* if you want to recalculate the position without using any cache information.
        
        Returns:
        
        An object with *x* and *y* properties.
        
        Example:
        (start code js)
        canvas.getPos(true); //returns { x: 900, y: 500 }
        (end code)
      */
      getPos: function(force){
        if(force || !this.pos) {
          return this.pos = $.getPos(this.getElement());
        }
        return this.pos;
      },
      /*
         Method: clear
         
         Clears the canvas.
      */
      clear: function(i){
        this.canvases[i||0].clear();
      },
      
      path: function(type, action){
        var ctx = this.canvases[0].getCtx();
        ctx.beginPath();
        action(ctx);
        ctx[type]();
        ctx.closePath();
      },
      
      createLabelContainer: function(type, idLabel, dim) {
        var NS = 'https://www.w3.org/2000/svg';
        if(type == 'HTML' || type == 'Native') {
          return $E('div', {
            'id': idLabel,
            'style': {
              'overflow': 'visible',
              'position': 'absolute',
              'top': 0,
              'left': 0,
              'width': dim.width + 'px',
              'height': 0
            }
          });
        } else if(type == 'SVG') {
          var svgContainer = document.createElementNS(NS, 'svg:svg');
          svgContainer.setAttribute("width", dim.width);
          svgContainer.setAttribute('height', dim.height);
          var style = svgContainer.style;
          style.position = 'absolute';
          style.left = style.top = '0px';
          var labelContainer = document.createElementNS(NS, 'svg:g');
          labelContainer.setAttribute('width', dim.width);
          labelContainer.setAttribute('height', dim.height);
          labelContainer.setAttribute('x', 0);
          labelContainer.setAttribute('y', 0);
          labelContainer.setAttribute('id', idLabel);
          svgContainer.appendChild(labelContainer);
          return svgContainer;
        }
      }
    });
    //base canvas wrapper
    Canvas.Base = {};
    Canvas.Base['2D'] = new Class({
      translateOffsetX: 0,
      translateOffsetY: 0,
      scaleOffsetX: 1,
      scaleOffsetY: 1,
  
      initialize: function(viz) {
        this.viz = viz;
        this.opt = viz.config;
        this.size = false;
        this.createCanvas();
        this.translateToCenter();
      },
      createCanvas: function() {
        var opt = this.opt,
            width = opt.width,
            height = opt.height;
        this.canvas = $E('canvas', {
          'id': opt.injectInto + opt.idSuffix,
          'width': width,
          'height': height,
          'style': {
            'position': 'absolute',
            'top': 0,
            'left': 0,
            'width': width + 'px',
            'height': height + 'px'
          }
        });
      },
      getCtx: function() {
        if(!this.ctx) 
          return this.ctx = this.canvas.getContext('2d');
        return this.ctx;
      },
      getSize: function() {
        if(this.size) return this.size;
        var canvas = this.canvas;
        return this.size = {
          width: canvas.width,
          height: canvas.height
        };
      },
      translateToCenter: function(ps) {
        var size = this.getSize(),
            width = ps? (size.width - ps.width - this.translateOffsetX*2) : size.width;
            height = ps? (size.height - ps.height - this.translateOffsetY*2) : size.height;
        var ctx = this.getCtx();
        ps && ctx.scale(1/this.scaleOffsetX, 1/this.scaleOffsetY);
        ctx.translate(width/2, height/2);
      },
      resize: function(width, height) {
        var size = this.getSize(),
            canvas = this.canvas,
            styles = canvas.style;
        this.size = false;
        canvas.width = width;
        canvas.height = height;
        styles.width = width + "px";
        styles.height = height + "px";
        //small ExCanvas fix
        if(!supportsCanvas) {
          this.translateToCenter(size);
        } else {
          this.translateToCenter();
        }
        this.translateOffsetX =
          this.translateOffsetY = 0;
        this.scaleOffsetX = 
          this.scaleOffsetY = 1;
        this.clear();
        this.viz.resize(width, height, this);
      },
      translate: function(x, y, disablePlot) {
        var sx = this.scaleOffsetX,
            sy = this.scaleOffsetY;
        this.translateOffsetX += x*sx;
        this.translateOffsetY += y*sy;
        this.getCtx().translate(x, y);
        !disablePlot && this.plot();
      },
      scale: function(x, y, disablePlot) {
        this.scaleOffsetX *= x;
        this.scaleOffsetY *= y;
        this.getCtx().scale(x, y);
        !disablePlot && this.plot();
      },
      clear: function(){
        var size = this.getSize(),
            ox = this.translateOffsetX,
            oy = this.translateOffsetY,
            sx = this.scaleOffsetX,
            sy = this.scaleOffsetY;
        this.getCtx().clearRect((-size.width / 2 - ox) * 1/sx, 
                                (-size.height / 2 - oy) * 1/sy, 
                                size.width * 1/sx, size.height * 1/sy);
      },
      plot: function() {
        this.clear();
        this.viz.plot(this);
      }
    });
    //background canvases
    //TODO(nico): document this!
    Canvas.Background = {};
    Canvas.Background.Circles = new Class({
      initialize: function(viz, options) {
        this.viz = viz;
        this.config = $.merge({
          idSuffix: '-bkcanvas',
          levelDistance: 100,
          numberOfCircles: 6,
          CanvasStyles: {},
          offset: 0
        }, options);
      },
      resize: function(width, height, base) {
        this.plot(base);
      },
      plot: function(base) {
        var canvas = base.canvas,
            ctx = base.getCtx(),
            conf = this.config,
            styles = conf.CanvasStyles;
        //set canvas styles
        for(var s in styles) ctx[s] = styles[s];
        var n = conf.numberOfCircles,
            rho = conf.levelDistance;
        for(var i=1; i<=n; i++) {
          ctx.beginPath();
          ctx.arc(0, 0, rho * i, 0, 2 * Math.PI, false);
          ctx.stroke();
          ctx.closePath();
        }
        //TODO(nico): print labels too!
      }
    });
  })();
  
  
  /*
       An object containing multiple type of transformations. 
  */
  
  $jit.Trans = {
    $extend: true,
    
    linear: function(p){
      return p;
    }
  };
  
  var Trans = $jit.Trans;
  
  (function(){
  
    var makeTrans = function(transition, params){
      params = $.splat(params);
      return $.extend(transition, {
        easeIn: function(pos){
          return transition(pos, params);
        },
        easeOut: function(pos){
          return 1 - transition(1 - pos, params);
        },
        easeInOut: function(pos){
          return (pos <= 0.5)? transition(2 * pos, params) / 2 : (2 - transition(
              2 * (1 - pos), params)) / 2;
        }
      });
    };
  
    var transitions = {
  
      Pow: function(p, x){
        return Math.pow(p, x[0] || 6);
      },
  
      Expo: function(p){
        return Math.pow(2, 8 * (p - 1));
      },
  
      Circ: function(p){
        return 1 - Math.sin(Math.acos(p));
      },
  
      Sine: function(p){
        return 1 - Math.sin((1 - p) * Math.PI / 2);
      },
  
      Back: function(p, x){
        x = x[0] || 1.618;
        return Math.pow(p, 2) * ((x + 1) * p - x);
      },
  
      Bounce: function(p){
        var value;
        for ( var a = 0, b = 1; 1; a += b, b /= 2) {
          if (p >= (7 - 4 * a) / 11) {
            value = b * b - Math.pow((11 - 6 * a - 11 * p) / 4, 2);
            break;
          }
        }
        return value;
      },
  
      Elastic: function(p, x){
        return Math.pow(2, 10 * --p)
            * Math.cos(20 * p * Math.PI * (x[0] || 1) / 3);
      }
  
    };
  
    $.each(transitions, function(val, key){
      Trans[key] = makeTrans(val);
    });
  
    $.each( [
        'Quad', 'Cubic', 'Quart', 'Quint'
    ], function(elem, i){
      Trans[elem] = makeTrans(function(p){
        return Math.pow(p, [
          i + 2
        ]);
      });
    });
  
  })();
  
  /*
     A Class that can perform animations for generic objects.
  
     If you are looking for animation transitions please take a look at the <Trans> object.
  
     Used by:
  
     <Graph.Plot>
     
     Based on:
     
     The Animation class is based in the MooTools Framework <http://mootools.net>. Copyright (c) 2006-2009 Valerio Proietti, <http://mad4milk.net/>. MIT license <http://mootools.net/license.txt>.
  
  */
  
  var Animation = new Class( {
  
    initialize: function(options){
      this.setOptions(options);
    },
  
    setOptions: function(options){
      var opt = {
        duration: 2500,
        fps: 40,
        transition: Trans.Quart.easeInOut,
        compute: $.empty,
        complete: $.empty,
        link: 'ignore'
      };
      this.opt = $.merge(opt, options || {});
      return this;
    },
  
    step: function(){
      var time = $.time(), opt = this.opt;
      if (time < this.time + opt.duration) {
        var delta = opt.transition((time - this.time) / opt.duration);
        opt.compute(delta);
      } else {
        this.timer = clearInterval(this.timer);
        opt.compute(1);
        opt.complete();
      }
    },
  
    start: function(){
      if (!this.check())
        return this;
      this.time = 0;
      this.startTimer();
      return this;
    },
  
    startTimer: function(){
      var that = this, fps = this.opt.fps;
      if (this.timer)
        return false;
      this.time = $.time() - this.time;
      this.timer = setInterval((function(){
        that.step();
      }), Math.round(1000 / fps));
      return true;
    },
  
    pause: function(){
      this.stopTimer();
      return this;
    },
  
    resume: function(){
      this.startTimer();
      return this;
    },
  
    stopTimer: function(){
      if (!this.timer)
        return false;
      this.time = $.time() - this.time;
      this.timer = clearInterval(this.timer);
      return true;
    },
  
    check: function(){
      if (!this.timer)
        return true;
      if (this.opt.link == 'cancel') {
        this.stopTimer();
        return true;
      }
      return false;
    }
  });
  
  
  /*
   * File: Extras.js
   * 
   * Provides Extras such as Tips and Style Effects.
   * 
   * Description:
   * 
   * Provides the <Tips> and <NodeStyles> classes and functions.
   *
   */
  
  /*
   * Manager for mouse events (clicking and mouse moving).
   * 
   * This class is used for registering objects implementing onClick
   * and onMousemove methods. These methods are called when clicking or
   * moving the mouse around  the Canvas.
   * For now, <Tips> and <NodeStyles> are classes implementing these methods.
   * 
   */
  var ExtrasInitializer = {
    initialize: function(className, viz) {
      this.viz = viz;
      this.canvas = viz.canvas;
      this.config = viz.config[className];
      this.nodeTypes = viz.fx.nodeTypes;
      var type = this.config.type;
      this.dom = type == 'auto'? (viz.config.Label.type != 'Native') : (type != 'Native');
      this.labelContainer = this.dom && viz.labels.getLabelContainer();
      this.isEnabled() && this.initializePost();
    },
    initializePost: $.empty,
    setAsProperty: $.lambda(false),
    isEnabled: function() {
      return this.config.enable;
    },
    isLabel: function(e, win, group) {
      e = $.event.get(e, win);
      var labelContainer = this.labelContainer,
          target = e.target || e.srcElement,
          related = e.relatedTarget;
      if(group) {
        return related && related == this.viz.canvas.getCtx().canvas 
            && !!target && this.isDescendantOf(target, labelContainer);
      } else {
        return this.isDescendantOf(target, labelContainer);
      }
    },
    isDescendantOf: function(elem, par) {
      while(elem && elem.parentNode) {
        if(elem.parentNode == par)
          return elem;
        elem = elem.parentNode;
      }
      return false;
    }
  };
  
  var EventsInterface = {
    onMouseUp: $.empty,
    onMouseDown: $.empty,
    onMouseMove: $.empty,
    onMouseOver: $.empty,
    onMouseOut: $.empty,
    onMouseWheel: $.empty,
    onTouchStart: $.empty,
    onTouchMove: $.empty,
    onTouchEnd: $.empty,
    onTouchCancel: $.empty
  };
  
  var MouseEventsManager = new Class({
    initialize: function(viz) {
      this.viz = viz;
      this.canvas = viz.canvas;
      this.node = false;
      this.edge = false;
      this.registeredObjects = [];
      this.attachEvents();
    },
    
    attachEvents: function() {
      var htmlCanvas = this.canvas.getElement(), 
          that = this;
      htmlCanvas.oncontextmenu = $.lambda(false);
      $.addEvents(htmlCanvas, {
        'mouseup': function(e, win) {
          var event = $.event.get(e, win);
          that.handleEvent('MouseUp', e, win, 
              that.makeEventObject(e, win), 
              $.event.isRightClick(event));
        },
        'mousedown': function(e, win) {
          var event = $.event.get(e, win);
          that.handleEvent('MouseDown', e, win, that.makeEventObject(e, win), 
              $.event.isRightClick(event));
        },
        'mousemove': function(e, win) {
          that.handleEvent('MouseMove', e, win, that.makeEventObject(e, win));
        },
        'mouseover': function(e, win) {
          that.handleEvent('MouseOver', e, win, that.makeEventObject(e, win));
        },
        'mouseout': function(e, win) {
          that.handleEvent('MouseOut', e, win, that.makeEventObject(e, win));
        },
        'touchstart': function(e, win) {
          that.handleEvent('TouchStart', e, win, that.makeEventObject(e, win));
        },
        'touchmove': function(e, win) {
          that.handleEvent('TouchMove', e, win, that.makeEventObject(e, win));
        },
        'touchend': function(e, win) {
          that.handleEvent('TouchEnd', e, win, that.makeEventObject(e, win));
        }
      });
      //attach mousewheel event
      var handleMouseWheel = function(e, win) {
        var event = $.event.get(e, win);
        var wheel = $.event.getWheel(event);
        that.handleEvent('MouseWheel', e, win, wheel);
      };
      //TODO(nico): this is a horrible check for non-gecko browsers!
      if(!document.getBoxObjectFor && window.mozInnerScreenX == null) {
        $.addEvent(htmlCanvas, 'mousewheel', handleMouseWheel);
      } else {
        htmlCanvas.addEventListener('DOMMouseScroll', handleMouseWheel, false);
      }
    },
    
    register: function(obj) {
      this.registeredObjects.push(obj);
    },
    
    handleEvent: function() {
      var args = Array.prototype.slice.call(arguments),
          type = args.shift();
      for(var i=0, regs=this.registeredObjects, l=regs.length; i<l; i++) {
        regs[i]['on' + type].apply(regs[i], args);
      }
    },
    
    makeEventObject: function(e, win) {
      var that = this,
          graph = this.viz.graph,
          fx = this.viz.fx,
          ntypes = fx.nodeTypes,
          etypes = fx.edgeTypes;
      return {
        pos: false,
        node: false,
        edge: false,
        contains: false,
        getNodeCalled: false,
        getEdgeCalled: false,
        getPos: function() {
          //TODO(nico): check why this can't be cache anymore when using edge detection
          //if(this.pos) return this.pos;
          var canvas = that.viz.canvas,
              s = canvas.getSize(),
              p = canvas.getPos(),
              ox = canvas.translateOffsetX,
              oy = canvas.translateOffsetY,
              sx = canvas.scaleOffsetX,
              sy = canvas.scaleOffsetY,
              pos = $.event.getPos(e, win);
          this.pos = {
            x: (pos.x - p.x - s.width/2 - ox) * 1/sx,
            y: (pos.y - p.y - s.height/2 - oy) * 1/sy
          };
          return this.pos;
        },
        getNode: function() {
          if(this.getNodeCalled) return this.node;
          this.getNodeCalled = true;
          for(var id in graph.nodes) {
            var n = graph.nodes[id],
                geom = n && ntypes[n.getData('type')],
                contains = geom && geom.contains && geom.contains.call(fx, n, this.getPos());
            if(contains) {
              this.contains = contains;
              return that.node = this.node = n;
            }
          }
          return that.node = this.node = false;
        },
        getEdge: function() {
          if(this.getEdgeCalled) return this.edge;
          this.getEdgeCalled = true;
          var hashset = {};
          for(var id in graph.edges) {
            var edgeFrom = graph.edges[id];
            hashset[id] = true;
            for(var edgeId in edgeFrom) {
              if(edgeId in hashset) continue;
              var e = edgeFrom[edgeId],
                  geom = e && etypes[e.getData('type')],
                  contains = geom && geom.contains && geom.contains.call(fx, e, this.getPos());
              if(contains) {
                this.contains = contains;
                return that.edge = this.edge = e;
              }
            }
          }
          return that.edge = this.edge = false;
        },
        getContains: function() {
          if(this.getNodeCalled) return this.contains;
          this.getNode();
          return this.contains;
        }
      };
    }
  });
  
  /* 
   * Provides the initialization function for <NodeStyles> and <Tips> implemented 
   * by all main visualizations.
   *
   */
  var Extras = {
    initializeExtras: function() {
      var mem = new MouseEventsManager(this), that = this;
      $.each(['NodeStyles', 'Tips', 'Navigation', 'Events'], function(k) {
        var obj = new Extras.Classes[k](k, that);
        if(obj.isEnabled()) {
          mem.register(obj);
        }
        if(obj.setAsProperty()) {
          that[k.toLowerCase()] = obj;
        }
      });
    }   
  };
  
  Extras.Classes = {};
  /*
    Class: Events
     
    This class defines an Event API to be accessed by the user.
    The methods implemented are the ones defined in the <Options.Events> object.
  */
  
  Extras.Classes.Events = new Class({
    Implements: [ExtrasInitializer, EventsInterface],
    
    initializePost: function() {
      this.fx = this.viz.fx;
      this.ntypes = this.viz.fx.nodeTypes;
      this.etypes = this.viz.fx.edgeTypes;
      
      this.hovered = false;
      this.pressed = false;
      this.touched = false;
  
      this.touchMoved = false;
      this.moved = false;
      
    },
    
    setAsProperty: $.lambda(true),
    
    onMouseUp: function(e, win, event, isRightClick) {
      var evt = $.event.get(e, win);
      if(!this.moved) {
        if(isRightClick) {
          this.config.onRightClick(this.hovered, event, evt);
        } else {
          this.config.onClick(this.pressed, event, evt);
        }
      }
      if(this.pressed) {
        if(this.moved) {
          this.config.onDragEnd(this.pressed, event, evt);
        } else {
          this.config.onDragCancel(this.pressed, event, evt);
        }
        this.pressed = this.moved = false;
      }
    },
  
    onMouseOut: function(e, win, event) {
     //mouseout a label
     var evt = $.event.get(e, win), label;
     if(this.dom && (label = this.isLabel(e, win, true))) {
       this.config.onMouseLeave(this.viz.graph.getNode(label.id),
                                event, evt);
       this.hovered = false;
       return;
     }
     //mouseout canvas
     var rt = evt.relatedTarget,
         canvasWidget = this.canvas.getElement();
     while(rt && rt.parentNode) {
       if(canvasWidget == rt.parentNode) return;
       rt = rt.parentNode;
     }
     if(this.hovered) {
       this.config.onMouseLeave(this.hovered,
           event, evt);
       this.hovered = false;
     }
    },
    
    onMouseOver: function(e, win, event) {
      //mouseover a label
      var evt = $.event.get(e, win), label;
      if(this.dom && (label = this.isLabel(e, win, true))) {
        this.hovered = this.viz.graph.getNode(label.id);
        this.config.onMouseEnter(this.hovered,
                                 event, evt);
      }
    },
    
    onMouseMove: function(e, win, event) {
     var label, evt = $.event.get(e, win);
     if(this.pressed) {
       this.moved = true;
       this.config.onDragMove(this.pressed, event, evt);
       return;
     }
     if(this.dom) {
       this.config.onMouseMove(this.hovered,
           event, evt);
     } else {
       if(this.hovered) {
         var hn = this.hovered;
         var geom = hn.nodeFrom? this.etypes[hn.getData('type')] : this.ntypes[hn.getData('type')];
         var contains = geom && geom.contains 
           && geom.contains.call(this.fx, hn, event.getPos());
         if(contains) {
           this.config.onMouseMove(hn, event, evt);
           return;
         } else {
           this.config.onMouseLeave(hn, event, evt);
           this.hovered = false;
         }
       }
       if(this.hovered = (event.getNode() || (this.config.enableForEdges && event.getEdge()))) {
         this.config.onMouseEnter(this.hovered, event, evt);
       } else {
         this.config.onMouseMove(false, event, evt);
       }
     }
    },
    
    onMouseWheel: function(e, win, delta) {
      this.config.onMouseWheel(delta, $.event.get(e, win));
    },
    
    onMouseDown: function(e, win, event) {
      var evt = $.event.get(e, win), label;
      if(this.dom) {
        if(label = this.isLabel(e, win)) {
          this.pressed = this.viz.graph.getNode(label.id);
        }
      } else {
        this.pressed = event.getNode() || (this.config.enableForEdges && event.getEdge());
      }
      this.pressed && this.config.onDragStart(this.pressed, event, evt);
    },
    
    onTouchStart: function(e, win, event) {
      var evt = $.event.get(e, win), label;
      if(this.dom && (label = this.isLabel(e, win))) {
        this.touched = this.viz.graph.getNode(label.id);
      } else {
        this.touched = event.getNode() || (this.config.enableForEdges && event.getEdge());
      }
      this.touched && this.config.onTouchStart(this.touched, event, evt);
    },
    
    onTouchMove: function(e, win, event) {
      var evt = $.event.get(e, win);
      if(this.touched) {
        this.touchMoved = true;
        this.config.onTouchMove(this.touched, event, evt);
      }
    },
    
    onTouchEnd: function(e, win, event) {
      var evt = $.event.get(e, win);
      if(this.touched) {
        if(this.touchMoved) {
          this.config.onTouchEnd(this.touched, event, evt);
        } else {
          this.config.onTouchCancel(this.touched, event, evt);
        }
        this.touched = this.touchMoved = false;
      }
    }
  });
  
  /*
     Class: Tips
      
     A class containing tip related functions. This class is used internally.
     
     Used by:
     
     <ST>, <Sunburst>, <Hypertree>, <RGraph>, <TM>, <ForceDirected>, <Icicle>
     
     See also:
     
     <Options.Tips>
  */
  
  Extras.Classes.Tips = new Class({
    Implements: [ExtrasInitializer, EventsInterface],
    
    initializePost: function() {
      //add DOM tooltip
      if(document.body) {
        var tip = $('_tooltip') || document.createElement('div');
        tip.id = '_tooltip';
        tip.className = 'tip';
        $.extend(tip.style, {
          position: 'absolute',
          display: 'none',
          zIndex: 13000
        });
        document.body.appendChild(tip);
        this.tip = tip;
        this.node = false;
      }
    },
    
    setAsProperty: $.lambda(true),
    
    onMouseOut: function(e, win) {
      //mouseout a label
      var evt = $.event.get(e, win);
      if(this.dom && this.isLabel(e, win, true)) {
        this.hide(true);
        return;
      }
      //mouseout canvas
      var rt = e.relatedTarget,
          canvasWidget = this.canvas.getElement();
      while(rt && rt.parentNode) {
        if(canvasWidget == rt.parentNode) return;
        rt = rt.parentNode;
      }
      this.hide(false);
    },
    
    onMouseOver: function(e, win) {
      //mouseover a label
      var label;
      if(this.dom && (label = this.isLabel(e, win, false))) {
        this.node = this.viz.graph.getNode(label.id);
        this.config.onShow(this.tip, this.node, label);
      }
    },
    
    onMouseMove: function(e, win, opt) {
      if(this.dom && this.isLabel(e, win)) {
        this.setTooltipPosition($.event.getPos(e, win));
      }
      if(!this.dom) {
        var node = opt.getNode();
        if(!node) {
          this.hide(true);
          return;
        }
        if(this.config.force || !this.node || this.node.id != node.id) {
          this.node = node;
          this.config.onShow(this.tip, node, opt.getContains());
        }
        this.setTooltipPosition($.event.getPos(e, win));
      }
    },
    
    setTooltipPosition: function(pos) {
      var tip = this.tip, 
          style = tip.style, 
          cont = this.config;
      style.display = '';
      //get window dimensions
      var win = {
        'height': document.body.clientHeight,
        'width': document.body.clientWidth
      };
      //get tooltip dimensions
      var obj = {
        'width': tip.offsetWidth,
        'height': tip.offsetHeight  
      };
      //set tooltip position
      var x = cont.offsetX, y = cont.offsetY;
      style.top = ((pos.y + y + obj.height > win.height)?  
          (pos.y - obj.height - y) : pos.y + y) + 'px';
      style.left = ((pos.x + obj.width + x > win.width)? 
          (pos.x - obj.width - x) : pos.x + x) + 'px';
    },
    
    hide: function(triggerCallback) {
      this.tip.style.display = 'none';
      triggerCallback && this.config.onHide();
    }
  });
  
  /*
    Class: NodeStyles
     
    Change node styles when clicking or hovering a node. This class is used internally.
    
    Used by:
    
    <ST>, <Sunburst>, <Hypertree>, <RGraph>, <TM>, <ForceDirected>, <Icicle>
    
    See also:
    
    <Options.NodeStyles>
  */
  Extras.Classes.NodeStyles = new Class({
    Implements: [ExtrasInitializer, EventsInterface],
    
    initializePost: function() {
      this.fx = this.viz.fx;
      this.types = this.viz.fx.nodeTypes;
      this.nStyles = this.config;
      this.nodeStylesOnHover = this.nStyles.stylesHover;
      this.nodeStylesOnClick = this.nStyles.stylesClick;
      this.hoveredNode = false;
      this.fx.nodeFxAnimation = new Animation();
      
      this.down = false;
      this.move = false;
    },
    
    onMouseOut: function(e, win) {
      this.down = this.move = false;
      if(!this.hoveredNode) return;
      //mouseout a label
      if(this.dom && this.isLabel(e, win, true)) {
        this.toggleStylesOnHover(this.hoveredNode, false);
      }
      //mouseout canvas
      var rt = e.relatedTarget,
          canvasWidget = this.canvas.getElement();
      while(rt && rt.parentNode) {
        if(canvasWidget == rt.parentNode) return;
        rt = rt.parentNode;
      }
      this.toggleStylesOnHover(this.hoveredNode, false);
      this.hoveredNode = false;
    },
    
    onMouseOver: function(e, win) {
      //mouseover a label
      var label;
      if(this.dom && (label = this.isLabel(e, win, true))) {
        var node = this.viz.graph.getNode(label.id);
        if(node.selected) return;
        this.hoveredNode = node;
        this.toggleStylesOnHover(this.hoveredNode, true);
      }
    },
    
    onMouseDown: function(e, win, event, isRightClick) {
      if(isRightClick) return;
      var label;
      if(this.dom && (label = this.isLabel(e, win))) {
        this.down = this.viz.graph.getNode(label.id);
      } else if(!this.dom) {
        this.down = event.getNode();
      }
      this.move = false;
    },
    
    onMouseUp: function(e, win, event, isRightClick) {
      if(isRightClick) return;
      if(!this.move) {
        this.onClick(event.getNode());
      }
      this.down = this.move = false;
    },
    
    getRestoredStyles: function(node, type) {
      var restoredStyles = {}, 
          nStyles = this['nodeStylesOn' + type];
      for(var prop in nStyles) {
        restoredStyles[prop] = node.styles['$' + prop];
      }
      return restoredStyles;
    },
    
    toggleStylesOnHover: function(node, set) {
      if(this.nodeStylesOnHover) {
        this.toggleStylesOn('Hover', node, set);
      }
    },
  
    toggleStylesOnClick: function(node, set) {
      if(this.nodeStylesOnClick) {
        this.toggleStylesOn('Click', node, set);
      }
    },
    
    toggleStylesOn: function(type, node, set) {
      var viz = this.viz;
      var nStyles = this.nStyles;
      if(set) {
        var that = this;
        if(!node.styles) {
          node.styles = $.merge(node.data, {});
        }
        for(var s in this['nodeStylesOn' + type]) {
          var $s = '$' + s;
          if(!($s in node.styles)) {
              node.styles[$s] = node.getData(s); 
          }
        }
        viz.fx.nodeFx($.extend({
          'elements': {
            'id': node.id,
            'properties': that['nodeStylesOn' + type]
           },
           transition: Trans.Quart.easeOut,
           duration:300,
           fps:40
        }, this.config));
      } else {
        var restoredStyles = this.getRestoredStyles(node, type);
        viz.fx.nodeFx($.extend({
          'elements': {
            'id': node.id,
            'properties': restoredStyles
           },
           transition: Trans.Quart.easeOut,
           duration:300,
           fps:40
        }, this.config));
      }
    },
  
    onClick: function(node) {
      if(!node) return;
      var nStyles = this.nodeStylesOnClick;
      if(!nStyles) return;
      //if the node is selected then unselect it
      if(node.selected) {
        this.toggleStylesOnClick(node, false);
        delete node.selected;
      } else {
        //unselect all selected nodes...
        this.viz.graph.eachNode(function(n) {
          if(n.selected) {
            for(var s in nStyles) {
              n.setData(s, n.styles['$' + s], 'end');
            }
            delete n.selected;
          }
        });
        //select clicked node
        this.toggleStylesOnClick(node, true);
        node.selected = true;
        delete node.hovered;
        this.hoveredNode = false;
      }
    },
    
    onMouseMove: function(e, win, event) {
      //if mouse button is down and moving set move=true
      if(this.down) this.move = true;
      //already handled by mouseover/out
      if(this.dom && this.isLabel(e, win)) return;
      var nStyles = this.nodeStylesOnHover;
      if(!nStyles) return;
      
      if(!this.dom) {
        if(this.hoveredNode) {
          var geom = this.types[this.hoveredNode.getData('type')];
          var contains = geom && geom.contains && geom.contains.call(this.fx, 
              this.hoveredNode, event.getPos());
          if(contains) return;
        }
        var node = event.getNode();
        //if no node is being hovered then just exit
        if(!this.hoveredNode && !node) return;
        //if the node is hovered then exit
        if(node.hovered) return;
        //select hovered node
        if(node && !node.selected) {
          //check if an animation is running and exit it
          this.fx.nodeFxAnimation.stopTimer();
          //unselect all hovered nodes...
          this.viz.graph.eachNode(function(n) {
            if(n.hovered && !n.selected) {
              for(var s in nStyles) {
                n.setData(s, n.styles['$' + s], 'end');
              }
              delete n.hovered;
            }
          });
          //select hovered node
          node.hovered = true;
          this.hoveredNode = node;
          this.toggleStylesOnHover(node, true);
        } else if(this.hoveredNode && !this.hoveredNode.selected) {
          //check if an animation is running and exit it
          this.fx.nodeFxAnimation.stopTimer();
          //unselect hovered node
          this.toggleStylesOnHover(this.hoveredNode, false);
          delete this.hoveredNode.hovered;
          this.hoveredNode = false;
        }
      }
    }
  });
  
  Extras.Classes.Navigation = new Class({
    Implements: [ExtrasInitializer, EventsInterface],
    
    initializePost: function() {
      this.pos = false;
      this.pressed = false;
    },
    
    onMouseWheel: function(e, win, scroll) {
      if(!this.config.zooming) return;
      $.event.stop($.event.get(e, win));
      var val = this.config.zooming / 1000,
          ans = 1 + scroll * val;
      this.canvas.scale(ans, ans);
    },
    
    onMouseDown: function(e, win, eventInfo) {
      if(!this.config.panning) return;
      if(this.config.panning == 'avoid nodes' && (this.dom? this.isLabel(e, win) : eventInfo.getNode())) return;
      this.pressed = true;
      this.pos = eventInfo.getPos();
      var canvas = this.canvas,
          ox = canvas.translateOffsetX,
          oy = canvas.translateOffsetY,
          sx = canvas.scaleOffsetX,
          sy = canvas.scaleOffsetY;
      this.pos.x *= sx;
      this.pos.x += ox;
      this.pos.y *= sy;
      this.pos.y += oy;
    },
    
    onMouseMove: function(e, win, eventInfo) {
      if(!this.config.panning) return;
      if(!this.pressed) return;
      if(this.config.panning == 'avoid nodes' && (this.dom? this.isLabel(e, win) : eventInfo.getNode())) return;
      var thispos = this.pos, 
          currentPos = eventInfo.getPos(),
          canvas = this.canvas,
          ox = canvas.translateOffsetX,
          oy = canvas.translateOffsetY,
          sx = canvas.scaleOffsetX,
          sy = canvas.scaleOffsetY;
      currentPos.x *= sx;
      currentPos.y *= sy;
      currentPos.x += ox;
      currentPos.y += oy;
      var x = currentPos.x - thispos.x,
          y = currentPos.y - thispos.y;
      this.pos = currentPos;
      this.canvas.translate(x * 1/sx, y * 1/sy);
    },
    
    onMouseUp: function(e, win, eventInfo, isRightClick) {
      if(!this.config.panning) return;
      this.pressed = false;
    }
  });
  
  
  /*
   * File: Polar.js
   * 
   * Defines the <Polar> class.
   *
   * Description:
   *
   * The <Polar> class, just like the <Complex> class, is used by the <Hypertree>, <ST> and <RGraph> as a 2D point representation.
   *
   * See also:
   *
   * <http://en.wikipedia.org/wiki/Polar_coordinates>
   *
  */
  
  /*
     Class: Polar
  
     A multi purpose polar representation.
  
     Description:
   
     The <Polar> class, just like the <Complex> class, is used by the <Hypertree>, <ST> and <RGraph> as a 2D point representation.
   
     See also:
   
     <http://en.wikipedia.org/wiki/Polar_coordinates>
   
     Parameters:
  
        theta - An angle.
        rho - The norm.
  */
  
  var Polar = function(theta, rho) {
    this.theta = theta || 0;
    this.rho = rho || 0;
  };
  
  $jit.Polar = Polar;
  
  Polar.prototype = {
      /*
         Method: getc
      
         Returns a complex number.
      
         Parameters:
  
         simple - _optional_ If *true*, this method will return only an object holding x and y properties and not a <Complex> instance. Default's *false*.
  
        Returns:
      
            A complex number.
      */
      getc: function(simple) {
          return this.toComplex(simple);
      },
  
      /*
         Method: getp
      
         Returns a <Polar> representation.
      
         Returns:
      
            A variable in polar coordinates.
      */
      getp: function() {
          return this;
      },
  
  
      /*
         Method: set
      
         Sets a number.
  
         Parameters:
  
         v - A <Complex> or <Polar> instance.
      
      */
      set: function(v) {
          v = v.getp();
          this.theta = v.theta; this.rho = v.rho;
      },
  
      /*
         Method: setc
      
         Sets a <Complex> number.
  
         Parameters:
  
         x - A <Complex> number real part.
         y - A <Complex> number imaginary part.
      
      */
      setc: function(x, y) {
          this.rho = Math.sqrt(x * x + y * y);
          this.theta = Math.atan2(y, x);
          if(this.theta < 0) this.theta += Math.PI * 2;
      },
  
      /*
         Method: setp
      
         Sets a polar number.
  
         Parameters:
  
         theta - A <Polar> number angle property.
         rho - A <Polar> number rho property.
      
      */
      setp: function(theta, rho) {
          this.theta = theta; 
          this.rho = rho;
      },
  
      /*
         Method: clone
      
         Returns a copy of the current object.
      
         Returns:
      
            A copy of the real object.
      */
      clone: function() {
          return new Polar(this.theta, this.rho);
      },
  
      /*
         Method: toComplex
      
          Translates from polar to cartesian coordinates and returns a new <Complex> instance.
      
          Parameters:
  
          simple - _optional_ If *true* this method will only return an object with x and y properties (and not the whole <Complex> instance). Default's *false*.
   
          Returns:
      
            A new <Complex> instance.
      */
      toComplex: function(simple) {
          var x = Math.cos(this.theta) * this.rho;
          var y = Math.sin(this.theta) * this.rho;
          if(simple) return { 'x': x, 'y': y};
          return new Complex(x, y);
      },
  
      /*
         Method: add
      
          Adds two <Polar> instances.
      
         Parameters:
  
         polar - A <Polar> number.
  
         Returns:
      
            A new Polar instance.
      */
      add: function(polar) {
          return new Polar(this.theta + polar.theta, this.rho + polar.rho);
      },
      
      /*
         Method: scale
      
          Scales a polar norm.
      
          Parameters:
  
          number - A scale factor.
          
          Returns:
      
            A new Polar instance.
      */
      scale: function(number) {
          return new Polar(this.theta, this.rho * number);
      },
      
      /*
         Method: equals
      
         Comparison method.
  
         Returns *true* if the theta and rho properties are equal.
  
         Parameters:
  
         c - A <Polar> number.
  
         Returns:
  
         *true* if the theta and rho parameters for these objects are equal. *false* otherwise.
      */
      equals: function(c) {
          return this.theta == c.theta && this.rho == c.rho;
      },
      
      /*
         Method: $add
      
          Adds two <Polar> instances affecting the current object.
      
         Paramters:
  
         polar - A <Polar> instance.
  
         Returns:
      
            The changed object.
      */
      $add: function(polar) {
          this.theta = this.theta + polar.theta; this.rho += polar.rho;
          return this;
      },
  
      /*
         Method: $madd
      
          Adds two <Polar> instances affecting the current object. The resulting theta angle is modulo 2pi.
      
         Parameters:
  
         polar - A <Polar> instance.
  
         Returns:
      
            The changed object.
      */
      $madd: function(polar) {
          this.theta = (this.theta + polar.theta) % (Math.PI * 2); this.rho += polar.rho;
          return this;
      },
  
      
      /*
         Method: $scale
      
          Scales a polar instance affecting the object.
      
        Parameters:
  
        number - A scaling factor.
  
        Returns:
      
            The changed object.
      */
      $scale: function(number) {
          this.rho *= number;
          return this;
      },
      
      /*
        Method: isZero
     
        Returns *true* if the number is zero.
     
     */
      isZero: function () {
        var almostZero = 0.0001, abs = Math.abs;
        return abs(this.theta) < almostZero && abs(this.rho) < almostZero;
      },
  
      /*
         Method: interpolate
      
          Calculates a polar interpolation between two points at a given delta moment.
  
          Parameters:
        
          elem - A <Polar> instance.
          delta - A delta factor ranging [0, 1].
      
         Returns:
      
            A new <Polar> instance representing an interpolation between _this_ and _elem_
      */
      interpolate: function(elem, delta) {
          var pi = Math.PI, pi2 = pi * 2;
          var ch = function(t) {
              var a =  (t < 0)? (t % pi2) + pi2 : t % pi2;
              return a;
          };
          var tt = this.theta, et = elem.theta;
          var sum, diff = Math.abs(tt - et);
          if(diff == pi) {
            if(tt > et) {
              sum = ch((et + ((tt - pi2) - et) * delta)) ;
            } else {
              sum = ch((et - pi2 + (tt - (et)) * delta));
            }
          } else if(diff >= pi) {
            if(tt > et) {
              sum = ch((et + ((tt - pi2) - et) * delta)) ;
            } else {
              sum = ch((et - pi2 + (tt - (et - pi2)) * delta));
            }
          } else {  
            sum = ch((et + (tt - et) * delta)) ;
          }
          var r = (this.rho - elem.rho) * delta + elem.rho;
          return {
            'theta': sum,
            'rho': r
          };
      }
  };
  
  
  var $P = function(a, b) { return new Polar(a, b); };
  
  Polar.KER = $P(0, 0);
  
  
  
  /*
   * File: Complex.js
   * 
   * Defines the <Complex> class.
   *
   * Description:
   *
   * The <Complex> class, just like the <Polar> class, is used by the <Hypertree>, <ST> and <RGraph> as a 2D point representation.
   *
   * See also:
   *
   * <http://en.wikipedia.org/wiki/Complex_number>
   *
  */
  
  /*
     Class: Complex
      
     A multi-purpose Complex Class with common methods.
   
     Description:
   
     The <Complex> class, just like the <Polar> class, is used by the <Hypertree>, <ST> and <RGraph> as a 2D point representation.
   
     See also:
   
     <http://en.wikipedia.org/wiki/Complex_number>
  
     Parameters:
  
     x - _optional_ A Complex number real part.
     y - _optional_ A Complex number imaginary part.
   
  */
  
  var Complex = function(x, y) {
    this.x = x || 0;
    this.y = y || 0;
  };
  
  $jit.Complex = Complex;
  
  Complex.prototype = {
      /*
         Method: getc
      
         Returns a complex number.
      
         Returns:
      
            A complex number.
      */
      getc: function() {
          return this;
      },
  
      /*
         Method: getp
      
         Returns a <Polar> representation of this number.
      
         Parameters:
  
         simple - _optional_ If *true*, this method will return only an object holding theta and rho properties and not a <Polar> instance. Default's *false*.
  
         Returns:
      
            A variable in <Polar> coordinates.
      */
      getp: function(simple) {
          return this.toPolar(simple);
      },
  
  
      /*
         Method: set
      
         Sets a number.
  
         Parameters:
  
         c - A <Complex> or <Polar> instance.
      
      */
      set: function(c) {
        c = c.getc(true);
        this.x = c.x; 
        this.y = c.y;
      },
  
      /*
         Method: setc
      
         Sets a complex number.
  
         Parameters:
  
         x - A <Complex> number Real part.
         y - A <Complex> number Imaginary part.
      
      */
      setc: function(x, y) {
          this.x = x; 
          this.y = y;
      },
  
      /*
         Method: setp
      
         Sets a polar number.
  
         Parameters:
  
         theta - A <Polar> number theta property.
         rho - A <Polar> number rho property.
      
      */
      setp: function(theta, rho) {
          this.x = Math.cos(theta) * rho;
          this.y = Math.sin(theta) * rho;
      },
  
      /*
         Method: clone
      
         Returns a copy of the current object.
      
         Returns:
      
            A copy of the real object.
      */
      clone: function() {
          return new Complex(this.x, this.y);
      },
  
      /*
         Method: toPolar
      
         Transforms cartesian to polar coordinates.
      
         Parameters:
  
         simple - _optional_ If *true* this method will only return an object with theta and rho properties (and not the whole <Polar> instance). Default's *false*.
         
         Returns:
      
            A new <Polar> instance.
      */
      
      toPolar: function(simple) {
          var rho = this.norm();
          var atan = Math.atan2(this.y, this.x);
          if(atan < 0) atan += Math.PI * 2;
          if(simple) return { 'theta': atan, 'rho': rho };
          return new Polar(atan, rho);
      },
      /*
         Method: norm
      
         Calculates a <Complex> number norm.
      
         Returns:
      
            A real number representing the complex norm.
      */
      norm: function () {
          return Math.sqrt(this.squaredNorm());
      },
      
      /*
         Method: squaredNorm
      
         Calculates a <Complex> number squared norm.
      
         Returns:
      
            A real number representing the complex squared norm.
      */
      squaredNorm: function () {
          return this.x*this.x + this.y*this.y;
      },
  
      /*
         Method: add
      
         Returns the result of adding two complex numbers.
         
         Does not alter the original object.
  
         Parameters:
      
            pos - A <Complex> instance.
      
         Returns:
      
           The result of adding two complex numbers.
      */
      add: function(pos) {
          return new Complex(this.x + pos.x, this.y + pos.y);
      },
  
      /*
         Method: prod
      
         Returns the result of multiplying two <Complex> numbers.
         
         Does not alter the original object.
  
         Parameters:
      
            pos - A <Complex> instance.
      
         Returns:
      
           The result of multiplying two complex numbers.
      */
      prod: function(pos) {
          return new Complex(this.x*pos.x - this.y*pos.y, this.y*pos.x + this.x*pos.y);
      },
  
      /*
         Method: conjugate
      
         Returns the conjugate of this <Complex> number.
  
         Does not alter the original object.
  
         Returns:
      
           The conjugate of this <Complex> number.
      */
      conjugate: function() {
          return new Complex(this.x, -this.y);
      },
  
  
      /*
         Method: scale
      
         Returns the result of scaling a <Complex> instance.
         
         Does not alter the original object.
  
         Parameters:
      
            factor - A scale factor.
      
         Returns:
      
           The result of scaling this complex to a factor.
      */
      scale: function(factor) {
          return new Complex(this.x * factor, this.y * factor);
      },
  
      /*
         Method: equals
      
         Comparison method.
  
         Returns *true* if both real and imaginary parts are equal.
  
         Parameters:
  
         c - A <Complex> instance.
  
         Returns:
  
         A boolean instance indicating if both <Complex> numbers are equal.
      */
      equals: function(c) {
          return this.x == c.x && this.y == c.y;
      },
  
      /*
         Method: $add
      
         Returns the result of adding two <Complex> numbers.
         
         Alters the original object.
  
         Parameters:
      
            pos - A <Complex> instance.
      
         Returns:
      
           The result of adding two complex numbers.
      */
      $add: function(pos) {
          this.x += pos.x; this.y += pos.y;
          return this;    
      },
      
      /*
         Method: $prod
      
         Returns the result of multiplying two <Complex> numbers.
         
         Alters the original object.
  
         Parameters:
      
            pos - A <Complex> instance.
      
         Returns:
      
           The result of multiplying two complex numbers.
      */
      $prod:function(pos) {
          var x = this.x, y = this.y;
          this.x = x*pos.x - y*pos.y;
          this.y = y*pos.x + x*pos.y;
          return this;
      },
      
      /*
         Method: $conjugate
      
         Returns the conjugate for this <Complex>.
         
         Alters the original object.
  
         Returns:
      
           The conjugate for this complex.
      */
      $conjugate: function() {
          this.y = -this.y;
          return this;
      },
      
      /*
         Method: $scale
      
         Returns the result of scaling a <Complex> instance.
         
         Alters the original object.
  
         Parameters:
      
            factor - A scale factor.
      
         Returns:
      
           The result of scaling this complex to a factor.
      */
      $scale: function(factor) {
          this.x *= factor; this.y *= factor;
          return this;
      },
      
      /*
         Method: $div
      
         Returns the division of two <Complex> numbers.
         
         Alters the original object.
  
         Parameters:
      
            pos - A <Complex> number.
      
         Returns:
      
           The result of scaling this complex to a factor.
      */
      $div: function(pos) {
          var x = this.x, y = this.y;
          var sq = pos.squaredNorm();
          this.x = x * pos.x + y * pos.y; this.y = y * pos.x - x * pos.y;
          return this.$scale(1 / sq);
      },
  
      /*
        Method: isZero
     
        Returns *true* if the number is zero.
     
     */
      isZero: function () {
        var almostZero = 0.0001, abs = Math.abs;
        return abs(this.x) < almostZero && abs(this.y) < almostZero;
      }
  };
  
  var $C = function(a, b) { return new Complex(a, b); };
  
  Complex.KER = $C(0, 0);
  Complex.IM = $C(0, 1);
  
  
  
  $jit.geometry = {
    /**
     * The distance between two points
     * @param {Complex} p1
     * @param {Complex} p2
     */
    dist2 : function(p1, p2) {
      var dx = p1.x - p2.x,
          dy = p1.y - p2.y;
      return dx * dx + dy * dy;
    },
  
    /**
     * The distance between two points
     * @param {Complex} p1
     * @param {Complex} p2
     */
    dist : function(p1, p2) {
      return Math.sqrt(Geometry.dist2(p1,p2));
    },
  
    /**
     *
     * @param {Complex} p1
     * @param {Complex} p2
     * @param {Number} weight
     * @return {Complex}
     */
    weightedPoint: function(p1, p2, weight) {
      return $C((p2.x - p1.x) * weight + p1.x, (p2.y -p1.y) * weight + p1.y);
    },
  
    /**
     *
     * @param {Complex} p1
     * @param {Complex} p2
     * @param {Complex} p3
     */
    weightOfPoint: function(p1, p2, p3) {
      return (p3.x - p1.x) / (p2.x - p1.x);
    },
  
    /**
     * Tests whether all points are in a polygon
     * @param {Complex[]} pts Points to be tested.
     * @param {Complex[]} polygon The Polygon.
     */
    pointInPolygon : function(pts, polygon) {
      if (!(pts instanceof Array)) {
        pts = [pts];
      }
      if (polygon.length < 3) {
        return false;
      }
      var conj = [], start, stop, k, cx;
      $jit.util.each(pts, function() {
        conj.push(0);
      });
      for (var i = 0; i < polygon.length; i++) {
        start = polygon[i];
        stop = polygon[i + 1] || polygon[0];
        $jit.util.each(pts, function(pos, i) {
          if (start.y >= pos.y && stop.y < pos.y ||
              start.y <= pos.y && stop.y > pos.y) {
            // find inverse k
            k = (stop.x - start.x) / (stop.y - start.y);
            cx = (pos.y - start.y) * k + start.x;
            if (cx == pos.x) {
              return true;
            } else if (cx > pos.x) {
              conj[i]++;
            }
          }
          return true;
        });
      }
      conj = $jit.util.map(conj, function(conjs) {
        return conjs % 2 != 0;
      });
      return conj;
    },
  
    /**
     * Counter-clockwise is positive.
     *
     * @param {Complex} p1
     * @param {Complex} p2
     * @param {Complex} p3
     */
    cross: function(p1, p2, p3) {
      return (p2.x - p1.x) * (p3.y - p1.y) - (p2.y - p1.y) * (p3.x - p1.x);
    },
  
    /**
     * Reserves those l[0],l[1],c[i] is counter-clockwise
     *
     * @param {Complex[]} convex
     * @param {Complex[]} l as a ex line
     * @param {?Object} attached
     */
    convexCut : function(convex, l, attached) {
      if (convex.length < 3) {
        return [];
      }
      
      var result = [], 
      	i = 0, 
      	start, stop, c1, c2, sc, cut, 
      	cross = Geometry.cross, 
      	l0 = l[0], 
      	l1 = l[1];
      
      for (; i < convex.length; i++) {
        start = stop || convex[i];
        stop = convex[i + 1] || convex[0];
        if (start.x == stop.x && start.y == stop.y)
          continue;
        if ((c1 = cross(l0, l1, start)) > 0) {
          if ((c2 = cross(l0, l1, stop)) >= 0) {
            result.push(stop);
          } else {
            if (c1 - c2 !== 0) {
              sc = c1 / (c1 - c2);
              cut = $C((stop.x - start.x) * sc + start.x,
                  (stop.y - start.y) * sc + start.y);
              cut.attached = attached;
              result.push(cut);
            }
          }
        } else {
          if ((c2 = cross(l[0], l[1], stop)) > 0) {
            sc = c1 / (c1 - c2);
            cut = $C((stop.x - start.x) * sc + start.x,
                (stop.y - start.y) * sc + start.y);
            cut.attached = start.attached;
            result.push(cut, stop);
          } else if (c2 == 0) {
            if (c1) {
              result.push(stop);
            }
          }
        }
      }
      return result;
    },
  
    /**
     * Get the area of polygon
     * @param {Complex[]} p The polygon
     */
    area : function(p) {
      if (p.length < 3) {
        return 0;
      }
      var sum = 0, i = 2;
      for (; i < p.length; i++) {
        sum += Geometry.cross(p[0], p[i - 1], p[i]);
      }
      return sum * 0.5;
    },
  
    /**
     * Get the circumeter of polygon
     * @param {Complex[]} p The polygon
     */
    circum : function(p) {
      var circ = 0, i = 1;
      for (; i < p.length; i++) {
        var dx = p[i].x - p[i - 1].x;
        var dy = p[i].y - p[i - 1].y;
        circ += Math.sqrt(dx * dx + dy * dy);
      }
      return circ;
    },
  
    /**
     * Intersect two polygons
     * @param {Complex[]} c1
     * @param {Complex[]} c2
     */
    convexIntersect : function(c1, c2) {
      if (c1.length < 3 || c2.length < 3) {
        return [];
      }
      if (Geometry.area(c1) < 0) {
        c1.reverse();
      }
      if (Geometry.area(c2) < 0) {
        c2.reverse();
      }
      var i = 0, start, stop;
      for (; i < c2.length; i++) {
        start = c2[i];
        stop = c2[i + 1] || c2[0];
        c1 = Geometry.convexCut(c1, [start, stop]);
      }
      return c1;
    },
  
    /**
     * The bisector of two point
     * @param {Complex} p1
     * @param {Complex} p2
     * @returns {Number[]}
     */
    bisector : function(p1, p2) {
      return [
        2 * (p2.x - p1.x),
        2 * (p2.y - p1.y),
        -(p2.x * p2.x - p1.x * p1.x + p2.y * p2.y - p1.y * p1.y)];
    },
  
    /**
     * Get the intersection of two lines
     * @param {Number[]} l1
     * @param {Number[]} l2
     * @returns {Complex}
     */
    intersection : function(l1, l2) {
      var det = l1[0] * l2[1] - l1[1] * l2[0];
      if (det == 0) {
        if (l1[0] * l2[2] - l1[2] * l2[0] == 0) {
          return l1;
        }
        else {
          return null;
        }
      }
      return $C(
          -(l1[2] * l2[1] - l1[1] * l2[2]) / det,
          -(l1[0] * l2[2] - l1[2] * l2[0]) / det);
    },
  
    /**
     * Get the extent of a series of points
     * @param {Complex[]} bound
     * @param {Number[]} Extent of points
     */
    getExtent : function(bound) {
      if (!bound[0])
        return [0, 0, 0, 0];
      var l = bound[0].x, t = bound[0].y, r = l, b = t;
      bound.each(function(p) {
        if (l > p.x)
          l = p.x;
        if (t > p.y)
          t = p.y;
        if (r < p.x)
          r = p.x;
        if (b < p.y)
          b = p.y;
      });
      return [l, t, r, b];
    },
  
    /**
     * Offset a line.
     * @param {Complex[]} l
     * @param {Number} offset
     * @returns {Complex[]}
     */
    offsetLine : function(l, offset) {
      var dx = l[1].x - l[0].x,
          dy = l[1].y - l[0].y,
          r = dx * dx + dy * dy;
      r = Math.sqrt(r);
      r = offset / r;
      dx *= r;
      dy *= r;
      return [$C(l[0].x - dy, l[0].y + dx), $C(l[1].x - dy, l[1].y + dx)];
    },
  
    /**
     * The intersection of two segments
     * @param {Complex[]} l1
     * @param {Complex[]} l2
     * @param {Boolean} [constraint]
     * @returns {Complex}
     */
    intersectionSeg : function(l1, l2, constraint) {
      var c1 = Geometry.cross(l1[0], l2[0], l2[1]),
          c2 = Geometry.cross(l1[1], l2[0], l2[1]), k;
      if (c1 == c2) {
        return null;
      }
      k = c1 / (c1 - c2);
      if (constraint) {
        if (k < 0 || k > 1) {
          return null;
        }
        var c3 = Geometry.cross(l2[0], l1[0], l1[1]),
            c4 = Geometry.cross(l2[1], l1[0], l1[1]);
        if (c3 == c4) {
          return null;
        }
        var k2 = c3 / (c3 - c4);
        if (k2 < 0 || k2 > 1) {
          return null;
        }
      }
      return Geometry.weightedPoint(l1[0], l1[1], k);
    },
  
    /**
     * The centroid of triangle
     * @param {Complex[]} triangle
     */
    centroid3 : function(triangle) {
      return $C((triangle[0].x + triangle[1].x + triangle[2].x) * 0.333333333333,
          (triangle[0].y + triangle[1].y + triangle[2].y) * 0.333333333333);
    },
  
    /**
     *
     * @param {Complex[]} convex
     */
    centroid : function(convex) {
      if (convex.length == 1) {
        return convex[0];
      }
      var c3s = $C(0, 0), total = 0, i, area, c3;
      if (convex.area) {
        c3s.area = convex.area;
      }
      for (i = 2; i < convex.length; i++) {
        area = Geometry.area([convex[0], convex[i - 1], convex[i]]);
        if (Math.abs(area) > 1e-5) {
          c3 = Geometry.centroid3([convex[0], convex[i - 1], convex[i]]);
          total += area;
          c3s.x += area * c3.x;
          c3s.y += area * c3.y;
        }
      }
      total = 1 / total;
      c3s.x *= total;
      c3s.y *= total;
      return c3s;
    },
  
    inverse : function(l) {
      var dx = l.line[1].x - l.line[0].x,
          cdx = l.cline[1].x - l.cline[0].x, dy, cdy;
      if (dx == cdx && dx == 0) {
        dy = l.line[1].y - l.line[0].y;
        cdy = l.cline[1].y - l.cline[0].y;
        return ((dy > 0) ^ (cdy > 0));
      } else
        return ((dx > 0) ^ (cdx > 0));
    },
  
    offsetConvex : function(convex, offset) {
      if (convex.length < 3) {
        return [];
      }
      if (Geometry.area(convex) < 0) {
        convex.reverse();
      }
  
      var last_line = null, first_line = null, cnt = 0, i, start, stop, line, result;
      // Offset edges
      for (i = 0; i < convex.length; i++) {
        start = convex[i];
        stop = convex[i + 1] || convex[0];
        if (start.x == stop.x && start.y == stop.y) {
          continue;
        }
        line = {
          line : Geometry.offsetLine([start, stop], -offset),
          cline : [-1, -1]
        };
        line.prev = last_line;
        if (last_line) {
          last_line.next = line;
        }
        else {
          first_line = line;
        }
        last_line = line;
        cnt++;
      }
      last_line.next = first_line;
      first_line.prev = last_line;
  
      if (cnt < 3)
        return [];
      // Connect all the edges
      for (var start = first_line, stop = start.next; true; start = stop,stop = stop.next) {
        var inters = Geometry.intersectionSeg(start.line, stop.line);
        stop.cline[0] = start.cline[1] = inters;
        if (stop == first_line)
          break;
      }
  
      result = [];
      result.push(first_line.cline[1]);
      for (start = first_line.next; start != first_line; start = start.next) {
        result.push(start.cline[1]);
      }
      if (offset < 0) return Geometry.cleanConvexHull(result);
      return result;
    },
  
    cleanConvexHull: function(convex) {
      var last = convex[0], stack = [last], found = [], inter, np;
      for (var i = 1; i <= convex.length; i++) {
        var curr = convex[i] || convex[0];
        for (var j = stack.length - 1; j > 0; j --) {
          var p1 = stack[j], p2 = stack[j - 1];
          if (inter = Geometry.intersectionSeg([last, curr], [p1, p2], true)) {
            if(Geometry.area(np = [inter].concat(stack.slice(j))) > 0) {
              found.push(np);
            }
            stack.length = j;
            stack.push(inter);
          }
        }
        stack.push(curr);
        last = curr;
      }
      if (Geometry.area(stack)) found.push(stack);
      return found[0] || Geometry.centroid(convex);
    },
  
    randPointInTriangle : function(t) {
      var x = Math.random(),
          y = Math.random(),
          dx1, dy1, dx2, dy2;
      if (x + y > 1) {
        x = 1 - x;
        y = 1 - y;
      }
      dx1 = t[1].x - t[0].x;
      dy1 = t[1].y - t[0].y;
      dx2 = t[2].x - t[0].x;
      dy2 = t[2].y - t[0].y;
      return $C(
          t[0].x + dx1 * x + dx2 * y,
          t[0].y + dy1 * x + dy2 * y);
    },
  
    randPointInPolygon : function(polygon) {
      var argument = Math.random();
      if (polygon.length == 1) {
        return polygon[0];
      }
      if (polygon.length == 2) {
        return $C(polygon[0].x + argument * (polygon[1].x - polygon[0].x),
            polygon[0].y + argument * (polygon[1].y - polygon[0].y));
      }
      var odds = [],
          area = 0, i, a;
      for (i = 2; i < polygon.length; i++) {
        a = Geometry.cross(polygon[0], polygon[i - 1], polygon[i]);
        area += a;
        odds.push(a);
      }
      odds.forEach(function(o, i) {
        odds[i] = o / area;
      });
      for (var i = 0; i < polygon.length - 2; i++) {
        if (argument < odds[i]) {
          return Geometry.randPointInTriangle([polygon[0], polygon[i + 1], polygon[i + 2]]);
        }
        argument -= odds[i];
      }
      return Geometry.randPointInTriangle([
        polygon[0],
        polygon[polygon.length - 2],
        polygon[polygon.length - 1]]);
    },
  
    /**
     *
     * @param sites
     *            {[Array}
     */
    convexHull : function (sites) {
      var stack_top = 0, i, temp, base, result, N = sites.length;
      for (i = 1; i < N; i++) {
        if (sites[i].y < sites[0].y
            || (sites[i].y == sites[0].y && sites[i].x < sites[0].x)) {
          temp = sites[i];
          sites[i] = sites[0];
          sites[0] = temp;
        }
      }
      base = sites[0];
      sites.sort(Geometry.convexHull.polarComp(base));
      result = [sites[0], sites[1]];
      for (i = 2; i < N; i++) {
        while (result.length && Geometry.cross(result[result.length - 2], result[result.length - 1], sites[i]) <= 0) {
          result.pop();
        }
        result.push(sites[i]);
      }
      return result;
    },
  
    /**
     * Circumcenter of triangle
     *
     * @param {Array}
        *            triangle The triangle
     * @return {Complex}
     */
  
    circumcenter : function (triangle) {
      var bx = triangle[1].x - triangle[0].x,
          by = triangle[1].y - triangle[0].y,
          bl = bx * bx + by * by,
          cx = triangle[2].x - triangle[0].x,
          cy = triangle[2].y - triangle[0].y,
          cl = cx * cx + cy * cy,
          d = 2 * (bx * cy - by * cx),
          x = cy * bl - by * cl,
          y = bx * cl - cx * bl;
      return $C(x / d + triangle[0].x, y / d + triangle[0].y);
    },
  
    /**
     *
     * @param {Complex}
        *            p1
     * @param {Complex}
        *            p2
     * @param {number}
        *            y
     */
    hyperbola : function (p1, p2) {
      // TODO : finish this
      if (p1.x == p2.x) {
        var my = (p1.y + p2.y) * 0.5;
        return [function(x) {
          return my;
        }, function(x) {
          return my;
        }];
  
      } else {
        var l = -(p1.y - p2.y) / (p1.x - p2.x);
        var mx = (p1.x + p2.x) * 0.5;
        var my = (p1.y + p2.y) * 0.5;
        var d = mx - l * my;
        return [function(x) {
          var b = (x - x1) * l - p1.y;
          var c = p1.x * p1.x + p2.y * p2.y - x * x * +2 * (x - p1.x)
              * d;
          var d = (b * b - c);
          return -b - Math.sqrt(d);
        }, function(x) {
          var b = (x - x1) * l - p1.y;
          var c = p1.x * p1.x + p2.y * p2.y - x * x * +2 * (x - p1.x)
              * d;
          var d = (b * b - c);
          return -b + Math.sqrt(d);
        }];
  
      }
      return;
    },
  
    /**
     * Voronoi Tessellation with naive algorithm
     *
     * @param vertices
     *          [p1,p2,p3, ...]
     * @returns polygons [[p1,p2,p3,...], ...]
     */
    voronoi : function(vertices, boundary) {
      var polygon = vertices.map(function(v) {
        return boundary.slice(0);
      }), i, v, j, dx, dy, c, c2, t;
      for (i = 0; i < vertices.length; i++) {
        var v = vertices[i];
        for (j = i + 1; j < vertices.length; j++) {
          t = vertices[j];
          dx = t.x - v.x;
          dy = t.y - v.y;
          c = $C((v.x + t.x) * 0.5, (v.y + t.y) * 0.5);
          c2 = $C(c.x + dy, c.y - dx);
          polygon[i] = Geometry.convexCut(polygon[i], [ c2, c ], [ j ]);
          polygon[j] = Geometry.convexCut(polygon[j], [ c, c2 ], [ i ]);
        }
        polygon[i].area = v.area;
      }
      return polygon;
    }
  };
  
  $jit.geometry.convexHull.polarComp = function (base) {
    return function(p, q) {
      if (p == base) {
        return -1;
      }
      if (q == base) {
        return 1;
      }
      var cm = Geometry.cross(base, p, q);
      if (cm == 0) {
        if (!p.__distBase) {
          var dxp = base.x - p.x;
          var dyp = base.y - p.y;
          p.__distBase = [dxp * dxp + dyp * dyp];
        }
        if (!q.__distBase) {
          var dxq = base.x - q.x;
          var dyq = base.y - q.y;
          q.__distBase = [dxq * dxq + dyq * dyq];
        }
        if (p.__distBase[0] < q.__distBase[0]) {
          return -1;
        } else if (p.__distBase[0] == q.__distBase[0]) {
          return 0;
        } else {
          return 1;
        }
      } else if (cm > 0) {
        return -1;
      } else if (cm < 0) {
        return 1;
      }
    }
  };
  
  var Geometry = $jit.geometry;
  
  
  var Options = function() {
    var args = arguments;
    for(var i=0, l=args.length, ans={}; i<l; i++) {
      var opt = Options[args[i]];
      if(opt.$extend) {
        $.extend(ans, opt);
      } else {
        ans[args[i]] = opt;  
      }
    }
    return ans;
  };
  
  /*
   * File: Options.Canvas.js
   *
  */
  
  /*
    Object: Options.Canvas
    
    These are Canvas general options, like where to append it in the DOM, its dimensions, background, 
    and other more advanced options.
    
    Syntax:
    
    (start code js)
  
    Options.Canvas = {
      injectInto: 'id',
      type: '2D', //'3D'
      width: false,
      height: false,
      useCanvas: false,
      withLabels: true,
      background: false
    };  
    (end code)
    
    Example:
    
    (start code js)
    var viz = new $jit.Viz({
      injectInto: 'someContainerId',
      width: 500,
      height: 700
    });
    (end code)
    
    Parameters:
    
    injectInto - *required* (string|element) The id of the DOM container for the visualization. It can also be an Element provided that it has an id.
    type - (string) Context type. Default's 2D but can be 3D for webGL enabled browsers.
    width - (number) Default's to the *container's offsetWidth*. The width of the canvas.
    height - (number) Default's to the *container's offsetHeight*. The height of the canvas.
    useCanvas - (boolean|object) Default's *false*. You can pass another <Canvas> instance to be used by the visualization.
    withLabels - (boolean) Default's *true*. Whether to use a label container for the visualization.
    background - (boolean|object) Default's *false*. An object containing information about the rendering of a background canvas.
  */
  
  Options.Canvas = {
      $extend: true,
      
      injectInto: 'id',
      type: '2D',
      width: false,
      height: false,
      useCanvas: false,
      withLabels: true,
      background: false,
      
      Scene: {
        Lighting: {
          enable: false,
          ambient: [1, 1, 1],
          directional: {
            direction: { x: -100, y: -100, z: -100 },
            color: [0.5, 0.3, 0.1]
          }
        }
      }
  };
  
  /*
   * File: Options.Tree.js
   *
  */
  
  /*
    Object: Options.Tree
    
    Options related to (strict) Tree layout algorithms. These options are used by the <ST> visualization.
    
    Syntax:
    
    (start code js)
    Options.Tree = {
      orientation: "left",
      subtreeOffset: 8,
      siblingOffset: 5,
      indent:10,
      multitree: false,
      align:"center"
    };
    (end code)
    
    Example:
    
    (start code js)
    var st = new $jit.ST({
      orientation: 'left',
      subtreeOffset: 1,
      siblingOFfset: 5,
      multitree: true
    });
    (end code)
  
    Parameters:
      
    subtreeOffset - (number) Default's 8. Separation offset between subtrees.
    siblingOffset - (number) Default's 5. Separation offset between siblings.
    orientation - (string) Default's 'left'. Tree orientation layout. Possible values are 'left', 'top', 'right', 'bottom'.
    align - (string) Default's *center*. Whether the tree alignment is 'left', 'center' or 'right'.
    indent - (number) Default's 10. Used when *align* is left or right and shows an indentation between parent and children.
    multitree - (boolean) Default's *false*. Used with the node $orn data property for creating multitrees.
       
  */
  Options.Tree = {
      $extend: true,
      
      orientation: "left",
      subtreeOffset: 8,
      siblingOffset: 5,
      indent:10,
      multitree: false,
      align:"center"
  };
  
  
  /*
   * File: Options.Node.js
   *
  */
  
  /*
    Object: Options.Node
  
    Provides Node rendering options for Tree and Graph based visualizations.
  
    Syntax:
      
    (start code js)
    Options.Node = {
      overridable: false,
      type: 'circle',
      color: '#ccb',
      alpha: 1,
      dim: 3,
      height: 20,
      width: 90,
      autoHeight: false,
      autoWidth: false,
      lineWidth: 1,
      transform: true,
      align: "center",
      angularWidth:1,
      span:1,
      CanvasStyles: {}
    };
    (end code)
    
    Example:
    
    (start code js)
    var viz = new $jit.Viz({
      Node: {
        overridable: true,
        width: 30,
        autoHeight: true,
        type: 'rectangle'
      }
    });
    (end code)
    
    Parameters:
  
    overridable - (boolean) Default's *false*. Determine whether or not general node properties can be overridden by a particular <Graph.Node>.
    type - (string) Default's *circle*. Node's shape. Node built-in types include 'circle', 'rectangle', 'square', 'ellipse', 'triangle', 'star'. The default Node type might vary in each visualization. You can also implement (non built-in) custom Node types into your visualizations.
    color - (string) Default's *#ccb*. Node color.
    alpha - (number) Default's *1*. The Node's alpha value. *1* is for full opacity.
    dim - (number) Default's *3*. An extra parameter used by 'circle', 'square', 'triangle' and 'star' node types. Depending on each shape, this parameter can set the radius of a circle, half the length of the side of a square, half the base and half the height of a triangle or the length of a side of a star (concave decagon).
    height - (number) Default's *20*. Used by 'rectangle' and 'ellipse' node types. The height of the node shape.
    width - (number) Default's *90*. Used by 'rectangle' and 'ellipse' node types. The width of the node shape.
    autoHeight - (boolean) Default's *false*. Whether to set an auto height for the node depending on the content of the Node's label.
    autoWidth - (boolean) Default's *false*. Whether to set an auto width for the node depending on the content of the Node's label.
    lineWidth - (number) Default's *1*. Used only by some Node shapes. The line width of the strokes of a node.
    transform - (boolean) Default's *true*. Only used by the <Hypertree> visualization. Whether to scale the nodes according to the moebius transformation.
    align - (string) Default's *center*. Possible values are 'center', 'left' or 'right'. Used only by the <ST> visualization, these parameters are used for aligning nodes when some of they dimensions vary.
    angularWidth - (number) Default's *1*. Used in radial layouts (like <RGraph> or <Sunburst> visualizations). The amount of relative 'space' set for a node.
    span - (number) Default's *1*. Used in radial layouts (like <RGraph> or <Sunburst> visualizations). The angle span amount set for a node.
    CanvasStyles - (object) Default's an empty object (i.e. {}). Attach any other canvas specific property that you'd set to the canvas context before plotting a Node.
  
  */
  Options.Node = {
    $extend: false,
    
    overridable: false,
    type: 'circle',
    color: '#ccb',
    alpha: 1,
    dim: 3,
    height: 20,
    width: 90,
    autoHeight: false,
    autoWidth: false,
    lineWidth: 1,
    transform: true,
    align: "center",
    angularWidth:1,
    span:1,
    //Raw canvas styles to be
    //applied to the context instance
    //before plotting a node
    CanvasStyles: {}
  };
  
  
  /*
   * File: Options.Edge.js
   *
  */
  
  /*
    Object: Options.Edge
  
    Provides Edge rendering options for Tree and Graph based visualizations.
  
    Syntax:
      
    (start code js)
    Options.Edge = {
      overridable: false,
      type: 'line',
      color: '#ccb',
      lineWidth: 1,
      dim:15,
      alpha: 1,
      CanvasStyles: {}
    };
    (end code)
    
    Example:
    
    (start code js)
    var viz = new $jit.Viz({
      Edge: {
        overridable: true,
        type: 'line',
        color: '#fff',
        CanvasStyles: {
          shadowColor: '#ccc',
          shadowBlur: 10
        }
      }
    });
    (end code)
    
    Parameters:
      
     overridable - (boolean) Default's *false*. Determine whether or not general edges properties can be overridden by a particular <Graph.Adjacence>.
     type - (string) Default's 'line'. Edge styles include 'line', 'hyperline', 'arrow'. The default Edge type might vary in each visualization. You can also implement custom Edge types.
     color - (string) Default's '#ccb'. Edge color.
     lineWidth - (number) Default's *1*. Line/Edge width.
     alpha - (number) Default's *1*. The Edge's alpha value. *1* is for full opacity.
     dim - (number) Default's *15*. An extra parameter used by other complex shapes such as quadratic, bezier or arrow, to determine the shape's diameter.
     epsilon - (number) Default's *7*. Only used when using *enableForEdges* in <Options.Events>. This dimension is used to create an area for the line where the contains method for the edge returns *true*.
     CanvasStyles - (object) Default's an empty object (i.e. {}). Attach any other canvas specific property that you'd set to the canvas context before plotting an Edge.
  
    See also:
     
     If you want to know more about how to customize Node/Edge data per element, in the JSON or programmatically, take a look at this article.
  */
  Options.Edge = {
    $extend: false,
    
    overridable: false,
    type: 'line',
    color: '#ccb',
    lineWidth: 1,
    dim:15,
    alpha: 1,
    epsilon: 7,
  
    //Raw canvas styles to be
    //applied to the context instance
    //before plotting an edge
    CanvasStyles: {}
  };
  
  
  /*
   * File: Options.Fx.js
   *
  */
  
  /*
    Object: Options.Fx
  
    Provides animation options like duration of the animations, frames per second and animation transitions.  
  
    Syntax:
    
    (start code js)
      Options.Fx = {
        fps:40,
        duration: 2500,
        transition: $jit.Trans.Quart.easeInOut,
        clearCanvas: true
      };
    (end code)
    
    Example:
    
    (start code js)
    var viz = new $jit.Viz({
      duration: 1000,
      fps: 35,
      transition: $jit.Trans.linear
    });
    (end code)
    
    Parameters:
    
    clearCanvas - (boolean) Default's *true*. Whether to clear the frame/canvas when the viz is plotted or animated.
    duration - (number) Default's *2500*. Duration of the animation in milliseconds.
    fps - (number) Default's *40*. Frames per second.
    transition - (object) Default's *$jit.Trans.Quart.easeInOut*. The transition used for the animations. See below for a more detailed explanation.
    
    Object: $jit.Trans
    
    This object is used for specifying different animation transitions in all visualizations.
  
    There are many different type of animation transitions.
  
    linear:
  
    Displays a linear transition
  
    >Trans.linear
    
    (see Linear.png)
  
    Quad:
  
    Displays a Quadratic transition.
  
    >Trans.Quad.easeIn
    >Trans.Quad.easeOut
    >Trans.Quad.easeInOut
    
   (see Quad.png)
  
   Cubic:
  
   Displays a Cubic transition.
  
   >Trans.Cubic.easeIn
   >Trans.Cubic.easeOut
   >Trans.Cubic.easeInOut
  
   (see Cubic.png)
  
   Quart:
  
   Displays a Quartetic transition.
  
   >Trans.Quart.easeIn
   >Trans.Quart.easeOut
   >Trans.Quart.easeInOut
  
   (see Quart.png)
  
   Quint:
  
   Displays a Quintic transition.
  
   >Trans.Quint.easeIn
   >Trans.Quint.easeOut
   >Trans.Quint.easeInOut
  
   (see Quint.png)
  
   Expo:
  
   Displays an Exponential transition.
  
   >Trans.Expo.easeIn
   >Trans.Expo.easeOut
   >Trans.Expo.easeInOut
  
   (see Expo.png)
  
   Circ:
  
   Displays a Circular transition.
  
   >Trans.Circ.easeIn
   >Trans.Circ.easeOut
   >Trans.Circ.easeInOut
  
   (see Circ.png)
  
   Sine:
  
   Displays a Sineousidal transition.
  
   >Trans.Sine.easeIn
   >Trans.Sine.easeOut
   >Trans.Sine.easeInOut
  
   (see Sine.png)
  
   Back:
  
   >Trans.Back.easeIn
   >Trans.Back.easeOut
   >Trans.Back.easeInOut
  
   (see Back.png)
  
   Bounce:
  
   Bouncy transition.
  
   >Trans.Bounce.easeIn
   >Trans.Bounce.easeOut
   >Trans.Bounce.easeInOut
  
   (see Bounce.png)
  
   Elastic:
  
   Elastic curve.
  
   >Trans.Elastic.easeIn
   >Trans.Elastic.easeOut
   >Trans.Elastic.easeInOut
  
   (see Elastic.png)
   
   Based on:
       
   Easing and Transition animation methods are based in the MooTools Framework <http://mootools.net>. Copyright (c) 2006-2010 Valerio Proietti, <http://mad4milk.net/>. MIT license <http://mootools.net/license.txt>.
  
  
  */
  Options.Fx = {
    $extend: true,
    
    fps:40,
    duration: 2500,
    transition: $jit.Trans.Quart.easeInOut,
    clearCanvas: true
  };
  
  /*
   * File: Options.Label.js
   *
  */
  /*
    Object: Options.Label
  
    Provides styling for Labels such as font size, family, etc. Also sets Node labels as HTML, SVG or Native canvas elements.  
  
    Syntax:
    
    (start code js)
      Options.Label = {
        overridable: false,
        type: 'HTML', //'SVG', 'Native'
        style: ' ',
        size: 10,
        family: 'sans-serif',
        textAlign: 'center',
        textBaseline: 'alphabetic',
        color: '#fff'
      };
    (end code)
    
    Example:
    
    (start code js)
    var viz = new $jit.Viz({
      Label: {
        type: 'Native',
        size: 11,
        color: '#ccc'
      }
    });
    (end code)
    
    Parameters:
      
    overridable - (boolean) Default's *false*. Determine whether or not general label properties can be overridden by a particular <Graph.Node>.
    type - (string) Default's *HTML*. The type for the labels. Can be 'HTML', 'SVG' or 'Native' canvas labels.
    style - (string) Default's *empty string*. Can be 'italic' or 'bold'. This parameter is only taken into account when using 'Native' canvas labels. For DOM based labels the className *node* is added to the DOM element for styling via CSS. You can also use <Options.Controller> methods to style individual labels.
    size - (number) Default's *10*. The font's size. This parameter is only taken into account when using 'Native' canvas labels. For DOM based labels the className *node* is added to the DOM element for styling via CSS. You can also use <Options.Controller> methods to style individual labels.
    family - (string) Default's *sans-serif*. The font's family. This parameter is only taken into account when using 'Native' canvas labels. For DOM based labels the className *node* is added to the DOM element for styling via CSS. You can also use <Options.Controller> methods to style individual labels.
    color - (string) Default's *#fff*. The font's color. This parameter is only taken into account when using 'Native' canvas labels. For DOM based labels the className *node* is added to the DOM element for styling via CSS. You can also use <Options.Controller> methods to style individual labels.
  */
  Options.Label = {
    $extend: false,
    
    overridable: false,
    type: 'HTML', //'SVG', 'Native'
    style: ' ',
    size: 10,
    family: 'sans-serif',
    textAlign: 'center',
    textBaseline: 'alphabetic',
    color: '#fff'
  };
  
  
  /*
   * File: Options.Tips.js
   *
   */
  
  /*
    Object: Options.Tips
    
    Tips options
    
    Syntax:
      
    (start code js)
    Options.Tips = {
      enable: false,
      type: 'auto',
      offsetX: 20,
      offsetY: 20,
      onShow: $.empty,
      onHide: $.empty
    };
    (end code)
    
    Example:
    
    (start code js)
    var viz = new $jit.Viz({
      Tips: {
        enable: true,
        type: 'Native',
        offsetX: 10,
        offsetY: 10,
        onShow: function(tip, node) {
          tip.innerHTML = node.name;
        }
      }
    });
    (end code)
  
    Parameters:
  
    enable - (boolean) Default's *false*. If *true*, a tooltip will be shown when a node is hovered. The tooltip is a div DOM element having "tip" as CSS class. 
    type - (string) Default's *auto*. Defines where to attach the MouseEnter/Leave tooltip events. Possible values are 'Native' to attach them to the canvas or 'HTML' to attach them to DOM label elements (if defined). 'auto' sets this property to the value of <Options.Label>'s *type* property.
    offsetX - (number) Default's *20*. An offset added to the current tooltip x-position (which is the same as the current mouse position). Default's 20.
    offsetY - (number) Default's *20*. An offset added to the current tooltip y-position (which is the same as the current mouse position). Default's 20.
    onShow(tip, node) - This callack is used right before displaying a tooltip. The first formal parameter is the tip itself (which is a DivElement). The second parameter may be a <Graph.Node> for graph based visualizations or an object with label, value properties for charts.
    onHide() - This callack is used when hiding a tooltip.
  
  */
  Options.Tips = {
    $extend: false,
    
    enable: false,
    type: 'auto',
    offsetX: 20,
    offsetY: 20,
    force: false,
    onShow: $.empty,
    onHide: $.empty
  };
  
  
  /*
   * File: Options.NodeStyles.js
   *
   */
  
  /*
    Object: Options.NodeStyles
    
    Apply different styles when a node is hovered or selected.
    
    Syntax:
      
    (start code js)
    Options.NodeStyles = {
      enable: false,
      type: 'auto',
      stylesHover: false,
      stylesClick: false
    };
    (end code)
    
    Example:
    
    (start code js)
    var viz = new $jit.Viz({
      NodeStyles: {
        enable: true,
        type: 'Native',
        stylesHover: {
          dim: 30,
          color: '#fcc'
        },
        duration: 600
      }
    });
    (end code)
  
    Parameters:
    
    enable - (boolean) Default's *false*. Whether to enable this option.
    type - (string) Default's *auto*. Use this to attach the hover/click events in the nodes or the nodes labels (if they have been defined as DOM elements: 'HTML' or 'SVG', see <Options.Label> for more details). The default 'auto' value will set NodeStyles to the same type defined for <Options.Label>.
    stylesHover - (boolean|object) Default's *false*. An object with node styles just like the ones defined for <Options.Node> or *false* otherwise.
    stylesClick - (boolean|object) Default's *false*. An object with node styles just like the ones defined for <Options.Node> or *false* otherwise.
  */
  
  Options.NodeStyles = {
    $extend: false,
    
    enable: false,
    type: 'auto',
    stylesHover: false,
    stylesClick: false
  };
  
  
  /*
   * File: Options.Events.js
   *
  */
  
  /*
    Object: Options.Events
    
    Configuration for adding mouse/touch event handlers to Nodes.
    
    Syntax:
    
    (start code js)
    Options.Events = {
      enable: false,
      enableForEdges: false,
      type: 'auto',
      onClick: $.empty,
      onRightClick: $.empty,
      onMouseMove: $.empty,
      onMouseEnter: $.empty,
      onMouseLeave: $.empty,
      onDragStart: $.empty,
      onDragMove: $.empty,
      onDragCancel: $.empty,
      onDragEnd: $.empty,
      onTouchStart: $.empty,
      onTouchMove: $.empty,
      onTouchEnd: $.empty,
      onTouchCancel: $.empty,
      onMouseWheel: $.empty
    };
    (end code)
    
    Example:
    
    (start code js)
    var viz = new $jit.Viz({
      Events: {
        enable: true,
        onClick: function(node, eventInfo, e) {
          viz.doSomething();
        },
        onMouseEnter: function(node, eventInfo, e) {
          viz.canvas.getElement().style.cursor = 'pointer';
        },
        onMouseLeave: function(node, eventInfo, e) {
          viz.canvas.getElement().style.cursor = '';
        }
      }
    });
    (end code)
    
    Parameters:
    
    enable - (boolean) Default's *false*. Whether to enable the Event system.
    enableForEdges - (boolean) Default's *false*. Whether to track events also in arcs. If *true* the same callbacks -described below- are used for nodes *and* edges. A simple duck type check for edges is to check for *node.nodeFrom*.
    type - (string) Default's 'auto'. Whether to attach the events onto the HTML labels (via event delegation) or to use the custom 'Native' canvas Event System of the library. 'auto' is set when you let the <Options.Label> *type* parameter decide this.
    onClick(node, eventInfo, e) - Triggered when a user performs a click in the canvas. *node* is the <Graph.Node> clicked or false if no node has been clicked. *e* is the grabbed event (should return the native event in a cross-browser manner). *eventInfo* is an object containing useful methods like *getPos* to get the mouse position relative to the canvas. 
    onRightClick(node, eventInfo, e) - Triggered when a user performs a right click in the canvas. *node* is the <Graph.Node> right clicked or false if no node has been clicked. *e* is the grabbed event (should return the native event in a cross-browser manner). *eventInfo* is an object containing useful methods like *getPos* to get the mouse position relative to the canvas. 
    onMouseMove(node, eventInfo, e) - Triggered when the user moves the mouse. *node* is the <Graph.Node> under the cursor as it's moving over the canvas or false if no node has been clicked. *e* is the grabbed event (should return the native event in a cross-browser manner).  *eventInfo* is an object containing useful methods like *getPos* to get the mouse position relative to the canvas.
    onMouseEnter(node, eventInfo, e) - Triggered when a user moves the mouse over a node. *node* is the <Graph.Node> that the mouse just entered. *e* is the grabbed event (should return the native event in a cross-browser manner). *eventInfo* is an object containing useful methods like *getPos* to get the mouse position relative to the canvas. 
    onMouseLeave(node, eventInfo, e) - Triggered when the user mouse-outs a node. *node* is the <Graph.Node> 'mouse-outed'. *e* is the grabbed event (should return the native event in a cross-browser manner). *eventInfo* is an object containing useful methods like *getPos* to get the mouse position relative to the canvas. 
    onDragStart(node, eventInfo, e) - Triggered when the user mouse-downs over a node. *node* is the <Graph.Node> being pressed. *e* is the grabbed event (should return the native event in a cross-browser manner). *eventInfo* is an object containing useful methods like *getPos* to get the mouse position relative to the canvas. 
    onDragMove(node, eventInfo, e) - Triggered when a user, after pressing the mouse button over a node, moves the mouse around. *node* is the <Graph.Node> being dragged. *e* is the grabbed event (should return the native event in a cross-browser manner). *eventInfo* is an object containing useful methods like *getPos* to get the mouse position relative to the canvas. 
    onDragEnd(node, eventInfo, e) - Triggered when a user finished dragging a node. *node* is the <Graph.Node> being dragged. *e* is the grabbed event (should return the native event in a cross-browser manner). *eventInfo* is an object containing useful methods like *getPos* to get the mouse position relative to the canvas. 
    onDragCancel(node, eventInfo, e) - Triggered when the user releases the mouse button over a <Graph.Node> that wasn't dragged (i.e. the user didn't perform any mouse movement after pressing the mouse button). *node* is the <Graph.Node> being dragged. *e* is the grabbed event (should return the native event in a cross-browser manner). *eventInfo* is an object containing useful methods like *getPos* to get the mouse position relative to the canvas. 
    onTouchStart(node, eventInfo, e) - Behaves just like onDragStart. 
    onTouchMove(node, eventInfo, e) - Behaves just like onDragMove. 
    onTouchEnd(node, eventInfo, e) - Behaves just like onDragEnd. 
    onTouchCancel(node, eventInfo, e) - Behaves just like onDragCancel.
    onMouseWheel(delta, e) - Triggered when the user uses the mouse scroll over the canvas. *delta* is 1 or -1 depending on the sense of the mouse scroll.
  */
  
  Options.Events = {
    $extend: false,
    
    enable: false,
    enableForEdges: false,
    type: 'auto',
    onClick: $.empty,
    onRightClick: $.empty,
    onMouseMove: $.empty,
    onMouseEnter: $.empty,
    onMouseLeave: $.empty,
    onDragStart: $.empty,
    onDragMove: $.empty,
    onDragCancel: $.empty,
    onDragEnd: $.empty,
    onTouchStart: $.empty,
    onTouchMove: $.empty,
    onTouchEnd: $.empty,
    onMouseWheel: $.empty
  };
  
  /*
   * File: Options.Navigation.js
   *
  */
  
  /*
    Object: Options.Navigation
    
    Panning and zooming options for Graph/Tree based visualizations. These options are implemented 
    by all visualizations except charts (<AreaChart>, <BarChart> and <PieChart>).
    
    Syntax:
    
    (start code js)
  
    Options.Navigation = {
      enable: false,
      type: 'auto',
      panning: false, //true, 'avoid nodes'
      zooming: false
    };
    
    (end code)
    
    Example:
      
    (start code js)
    var viz = new $jit.Viz({
      Navigation: {
        enable: true,
        panning: 'avoid nodes',
        zooming: 20
      }
    });
    (end code)
    
    Parameters:
    
    enable - (boolean) Default's *false*. Whether to enable Navigation capabilities.
    type - (string) Default's 'auto'. Whether to attach the navigation events onto the HTML labels (via event delegation) or to use the custom 'Native' canvas Event System of the library. When 'auto' set when you let the <Options.Label> *type* parameter decide this.
    panning - (boolean|string) Default's *false*. Set this property to *true* if you want to add Drag and Drop panning support to the visualization. You can also set this parameter to 'avoid nodes' to enable DnD panning but disable it if the DnD is taking place over a node. This is useful when some other events like Drag & Drop for nodes are added to <Graph.Nodes>.
    zooming - (boolean|number) Default's *false*. Set this property to a numeric value to turn mouse-scroll zooming on. The number will be proportional to the mouse-scroll sensitivity.
    
  */
  
  Options.Navigation = {
    $extend: false,
    
    enable: false,
    type: 'auto',
    panning: false, //true | 'avoid nodes'
    zooming: false
  };
  
  /*
   * File: Options.Controller.js
   *
  */
  
  /*
    Object: Options.Controller
    
    Provides controller methods. Controller methods are callback functions that get called at different stages 
    of the animation, computing or plotting of the visualization.
    
    Implemented by:
      
    All visualizations except charts (<AreaChart>, <BarChart> and <PieChart>).
    
    Syntax:
    
    (start code js)
  
    Options.Controller = {
      onBeforeCompute: $.empty,
      onAfterCompute:  $.empty,
      onCreateLabel:   $.empty,
      onPlaceLabel:    $.empty,
      onComplete:      $.empty,
      onBeforePlotLine:$.empty,
      onAfterPlotLine: $.empty,
      onBeforePlotNode:$.empty,
      onAfterPlotNode: $.empty,
      request:         false
    };
    
    (end code)
    
    Example:
      
    (start code js)
    var viz = new $jit.Viz({
      onBeforePlotNode: function(node) {
        if(node.selected) {
          node.setData('color', '#ffc');
        } else {
          node.removeData('color');
        }
      },
      onBeforePlotLine: function(adj) {
        if(adj.nodeFrom.selected && adj.nodeTo.selected) {
          adj.setData('color', '#ffc');
        } else {
          adj.removeData('color');
        }
      },
      onAfterCompute: function() {
        alert("computed!");
      }
    });
    (end code)
    
    Parameters:
  
     onBeforeCompute(node) - This method is called right before performing all computations and animations. The selected <Graph.Node> is passed as parameter.
     onAfterCompute() - This method is triggered after all animations or computations ended.
     onCreateLabel(domElement, node) - This method receives a new label DIV element as first parameter, and the corresponding <Graph.Node> as second parameter. This method will only be called once for each label. This method is useful when adding events or styles to the labels used by the JIT.
     onPlaceLabel(domElement, node) - This method receives a label DIV element as first parameter and the corresponding <Graph.Node> as second parameter. This method is called each time a label has been placed in the visualization, for example at each step of an animation, and thus it allows you to update the labels properties, such as size or position. Note that onPlaceLabel will be triggered after updating the labels positions. That means that, for example, the left and top css properties are already updated to match the nodes positions. Width and height properties are not set however.
     onBeforePlotNode(node) - This method is triggered right before plotting each <Graph.Node>. This method is useful for changing a node style right before plotting it.
     onAfterPlotNode(node) - This method is triggered right after plotting each <Graph.Node>.
     onBeforePlotLine(adj) - This method is triggered right before plotting a <Graph.Adjacence>. This method is useful for adding some styles to a particular edge before being plotted.
     onAfterPlotLine(adj) - This method is triggered right after plotting a <Graph.Adjacence>.
     onBeforeRemoveNode(node) - This method is triggered right before removing each <Graph.Node>.
     
      *Used in <ST>, <TM.Base> and <Icicle> visualizations*
      
      request(nodeId, level, onComplete) - This method is used for buffering information into the visualization. When clicking on an empty node, the visualization will make a request for this node's subtrees, specifying a given level for this subtree (defined by _levelsToShow_). Once the request is completed, the onComplete callback should be called with the given result. This is useful to provide on-demand information into the visualizations withought having to load the entire information from start. The parameters used by this method are _nodeId_, which is the id of the root of the subtree to request, _level_ which is the depth of the subtree to be requested (0 would mean just the root node). _onComplete_ is an object having the callback method _onComplete.onComplete(json)_ that should be called once the json has been retrieved.  
   
   */
  Options.Controller = {
    $extend: true,
    
    onBeforeCompute:   $.empty,
    onAfterCompute:    $.empty,
    onCreateLabel:     $.empty,
    onPlaceLabel:      $.empty,
    onComplete:        $.empty,
    onBeforePlotLine:  $.empty,
    onAfterPlotLine:   $.empty,
    onBeforePlotNode:  $.empty,
    onAfterPlotNode:   $.empty,
    onBeforeRemoveNode:$.empty,
    request:         false
  };
  
  
  /*
   * File: Graph.js
   *
  */
  
  /*
   Class: Graph
  
   A Graph Class that provides useful manipulation functions. You can find more manipulation methods in the <Graph.Util> object.
  
   An instance of this class can be accessed by using the *graph* parameter of any tree or graph visualization.
   
   Example:
  
   (start code js)
     //create new visualization
     var viz = new $jit.Viz(options);
     //load JSON data
     viz.loadJSON(json);
     //access model
     viz.graph; //<Graph> instance
   (end code)
   
   Implements:
   
   The following <Graph.Util> methods are implemented in <Graph>
   
    - <Graph.Util.getNode>
    - <Graph.Util.eachNode>
    - <Graph.Util.computeLevels>
    - <Graph.Util.eachBFS>
    - <Graph.Util.clean>
    - <Graph.Util.getClosestNodeToPos>
    - <Graph.Util.getClosestNodeToOrigin>
   
  */  
  
  $jit.Graph = new Class({
  
    initialize: function(opt, Node, Edge, Label) {
      var innerOptions = {
      'klass': Complex,
      'Node': {}
      };
      this.Node = Node;
      this.Edge = Edge;
      this.Label = Label;
      this.opt = $.merge(innerOptions, opt || {});
      this.nodes = {};
      this.edges = {};
      
      //add nodeList methods
      var that = this;
      this.nodeList = {};
      for(var p in Accessors) {
        that.nodeList[p] = (function(p) {
          return function() {
            var args = Array.prototype.slice.call(arguments);
            that.eachNode(function(n) {
              n[p].apply(n, args);
            });
          };
        })(p);
      }
  
   },
  
  /*
       Method: getNode
      
       Returns a <Graph.Node> by *id*.
  
       Parameters:
  
       id - (string) A <Graph.Node> id.
  
       Example:
  
       (start code js)
         var node = graph.getNode('nodeId');
       (end code)
  */  
   getNode: function(id) {
      if(this.hasNode(id)) return this.nodes[id];
      return false;
   },
  
   /*
       Method: get
      
       An alias for <Graph.Util.getNode>. Returns a node by *id*.
      
       Parameters:
      
       id - (string) A <Graph.Node> id.
      
       Example:
      
       (start code js)
         var node = graph.get('nodeId');
       (end code)
  */  
    get: function(id) {
      return this.getNode(id);
    },
  
   /*
     Method: getByName
    
     Returns a <Graph.Node> by *name*.
    
     Parameters:
    
     name - (string) A <Graph.Node> name.
    
     Example:
    
     (start code js)
       var node = graph.getByName('someName');
     (end code)
    */  
    getByName: function(name) {
      for(var id in this.nodes) {
        var n = this.nodes[id];
        if(n.name == name) return n;
      }
      return false;
    },
  
  /*
     Method: getAdjacence
    
     Returns a <Graph.Adjacence> object connecting nodes with ids *id* and *id2*.
  
     Parameters:
  
     id - (string) A <Graph.Node> id.
     id2 - (string) A <Graph.Node> id.
  */  
    getAdjacence: function (id, id2) {
      if(id in this.edges) {
        return this.edges[id][id2];
      }
      return false;
   },
  
      /*
       Method: addNode
      
       Adds a node.
       
       Parameters:
      
        obj - An object with the properties described below
  
        id - (string) A node id
        name - (string) A node's name
        data - (object) A node's data hash
  
      See also:
      <Graph.Node>
  
    */  
    addNode: function(obj) { 
     if(!this.nodes[obj.id]) {  
       var edges = this.edges[obj.id] = {};
       this.nodes[obj.id] = new Graph.Node($.extend({
          'id': obj.id,
          'name': obj.name,
          'data': $.merge(obj.data || {}, {}),
          'adjacencies': edges 
        }, this.opt.Node), 
        this.opt.klass, 
        this.Node, 
        this.Edge,
        this.Label);
      }
      return this.nodes[obj.id];
    },
    
      /*
       Method: addAdjacence
      
       Connects nodes specified by *obj* and *obj2*. If not found, nodes are created.
       
       Parameters:
      
        obj - (object) A <Graph.Node> object.
        obj2 - (object) Another <Graph.Node> object.
        data - (object) A data object. Used to store some extra information in the <Graph.Adjacence> object created.
  
      See also:
  
      <Graph.Node>, <Graph.Adjacence>
      */  
    addAdjacence: function (obj, obj2, data) {
      if(!this.hasNode(obj.id)) { this.addNode(obj); }
      if(!this.hasNode(obj2.id)) { this.addNode(obj2); }
      obj = this.nodes[obj.id]; obj2 = this.nodes[obj2.id];
      if(!obj.adjacentTo(obj2)) {
        var adjsObj = this.edges[obj.id] = this.edges[obj.id] || {};
        var adjsObj2 = this.edges[obj2.id] = this.edges[obj2.id] || {};
        adjsObj[obj2.id] = adjsObj2[obj.id] = new Graph.Adjacence(obj, obj2, data, this.Edge, this.Label);
        return adjsObj[obj2.id];
      }
      return this.edges[obj.id][obj2.id];
   },
  
      /*
       Method: removeNode
      
       Removes a <Graph.Node> matching the specified *id*.
  
       Parameters:
  
       id - (string) A node's id.
  
      */  
    removeNode: function(id) {
      if(this.hasNode(id)) {
        delete this.nodes[id];
        var adjs = this.edges[id];
        for(var to in adjs) {
          delete this.edges[to][id];
        }
        delete this.edges[id];
      }
    },
    
  /*
       Method: removeAdjacence
      
       Removes a <Graph.Adjacence> matching *id1* and *id2*.
  
       Parameters:
  
       id1 - (string) A <Graph.Node> id.
       id2 - (string) A <Graph.Node> id.
  */  
    removeAdjacence: function(id1, id2) {
      delete this.edges[id1][id2];
      delete this.edges[id2][id1];
    },
  
     /*
       Method: hasNode
      
       Returns a boolean indicating if the node belongs to the <Graph> or not.
       
       Parameters:
      
          id - (string) Node id.
     */  
    hasNode: function(id) {
      return id in this.nodes;
    },
    
    /*
      Method: empty
  
      Empties the Graph
  
    */
    empty: function() { this.nodes = {}; this.edges = {};}
  
  });
  
  var Graph = $jit.Graph;
  
  /*
   Object: Accessors
   
   Defines a set of methods for data, canvas and label styles manipulation implemented by <Graph.Node> and <Graph.Adjacence> instances.
   
   */
  var Accessors;
  
  (function () {
    var getDataInternal = function(prefix, prop, type, force, prefixConfig) {
      var data;
      type = type || 'current';
      prefix = "$" + (prefix ? prefix + "-" : "");
  
      if(type == 'current') {
        data = this.data;
      } else if(type == 'start') {
        data = this.startData;
      } else if(type == 'end') {
        data = this.endData;
      }
  
      var dollar = prefix + prop;
  
      if(force) {
        return data[dollar];
      }
  
      if(!this.Config.overridable)
        return prefixConfig[prop] || 0;
  
      return (dollar in data) ?
        data[dollar] : ((dollar in this.data) ? this.data[dollar] : (prefixConfig[prop] || 0));
    }
  
    var setDataInternal = function(prefix, prop, value, type) {
      type = type || 'current';
      prefix = '$' + (prefix ? prefix + '-' : '');
  
      var data;
  
      if(type == 'current') {
        data = this.data;
      } else if(type == 'start') {
        data = this.startData;
      } else if(type == 'end') {
        data = this.endData;
      }
  
      data[prefix + prop] = value;
    }
  
    var removeDataInternal = function(prefix, properties) {
      prefix = '$' + (prefix ? prefix + '-' : '');
      var that = this;
      $.each(properties, function(prop) {
        var pref = prefix + prop;
        delete that.data[pref];
        delete that.endData[pref];
        delete that.startData[pref];
      });
    }
  
    Accessors = {
      /*
      Method: getData
  
      Returns the specified data value property.
      This is useful for querying special/reserved <Graph.Node> data properties
      (i.e dollar prefixed properties).
  
      Parameters:
  
        prop  - (string) The name of the property. The dollar sign is not needed. For
                example *getData(width)* will return *data.$width*.
        type  - (string) The type of the data property queried. Default's "current". You can access *start* and *end* 
                data properties also. These properties are used when making animations.
        force - (boolean) Whether to obtain the true value of the property (equivalent to
                *data.$prop*) or to check for *node.overridable = true* first.
  
      Returns:
  
        The value of the dollar prefixed property or the global Node/Edge property
        value if *overridable=false*
  
      Example:
      (start code js)
       node.getData('width'); //will return node.data.$width if Node.overridable=true;
      (end code)
      */
      getData: function(prop, type, force) {
        return getDataInternal.call(this, "", prop, type, force, this.Config);
      },
  
  
      /*
      Method: setData
  
      Sets the current data property with some specific value.
      This method is only useful for reserved (dollar prefixed) properties.
  
      Parameters:
  
        prop  - (string) The name of the property. The dollar sign is not necessary. For
                example *setData(width)* will set *data.$width*.
        value - (mixed) The value to store.
        type  - (string) The type of the data property to store. Default's "current" but
                can also be "start" or "end".
  
      Example:
      
      (start code js)
       node.setData('width', 30);
      (end code)
      
      If we were to make an animation of a node/edge width then we could do
      
      (start code js)
        var node = viz.getNode('nodeId');
        //set start and end values
        node.setData('width', 10, 'start');
        node.setData('width', 30, 'end');
        //will animate nodes width property
        viz.fx.animate({
          modes: ['node-property:width'],
          duration: 1000
        });
      (end code)
      */
      setData: function(prop, value, type) {
        setDataInternal.call(this, "", prop, value, type);
      },
  
      /*
      Method: setDataset
  
      Convenience method to set multiple data values at once.
      
      Parameters:
      
      types - (array|string) A set of 'current', 'end' or 'start' values.
      obj - (object) A hash containing the names and values of the properties to be altered.
  
      Example:
      (start code js)
        node.setDataset(['current', 'end'], {
          'width': [100, 5],
          'color': ['#fff', '#ccc']
        });
        //...or also
        node.setDataset('end', {
          'width': 5,
          'color': '#ccc'
        });
      (end code)
      
      See also: 
      
      <Accessors.setData>
      
      */
      setDataset: function(types, obj) {
        types = $.splat(types);
        for(var attr in obj) {
          for(var i=0, val = $.splat(obj[attr]), l=types.length; i<l; i++) {
            this.setData(attr, val[i], types[i]);
          }
        }
      },
      
      /*
      Method: removeData
  
      Remove data properties.
  
      Parameters:
  
      One or more property names as arguments. The dollar sign is not needed.
  
      Example:
      (start code js)
      node.removeData('width'); //now the default width value is returned
      (end code)
      */
      removeData: function() {
        removeDataInternal.call(this, "", Array.prototype.slice.call(arguments));
      },
  
      /*
      Method: getCanvasStyle
  
      Returns the specified canvas style data value property. This is useful for
      querying special/reserved <Graph.Node> canvas style data properties (i.e.
      dollar prefixed properties that match with $canvas-<name of canvas style>).
  
      Parameters:
  
        prop  - (string) The name of the property. The dollar sign is not needed. For
                example *getCanvasStyle(shadowBlur)* will return *data[$canvas-shadowBlur]*.
        type  - (string) The type of the data property queried. Default's *current*. You can access *start* and *end* 
                data properties also.
                
      Example:
      (start code js)
        node.getCanvasStyle('shadowBlur');
      (end code)
      
      See also:
      
      <Accessors.getData>
      */
      getCanvasStyle: function(prop, type, force) {
        return getDataInternal.call(
            this, 'canvas', prop, type, force, this.Config.CanvasStyles);
      },
  
      /*
      Method: setCanvasStyle
  
      Sets the canvas style data property with some specific value.
      This method is only useful for reserved (dollar prefixed) properties.
      
      Parameters:
      
      prop - (string) Name of the property. Can be any canvas property like 'shadowBlur', 'shadowColor', 'strokeStyle', etc.
      value - (mixed) The value to set to the property.
      type - (string) Default's *current*. Whether to set *start*, *current* or *end* type properties.
      
      Example:
      
      (start code js)
       node.setCanvasStyle('shadowBlur', 30);
      (end code)
      
      If we were to make an animation of a node/edge shadowBlur canvas style then we could do
      
      (start code js)
        var node = viz.getNode('nodeId');
        //set start and end values
        node.setCanvasStyle('shadowBlur', 10, 'start');
        node.setCanvasStyle('shadowBlur', 30, 'end');
        //will animate nodes canvas style property for nodes
        viz.fx.animate({
          modes: ['node-style:shadowBlur'],
          duration: 1000
        });
      (end code)
      
      See also:
      
      <Accessors.setData>.
      */
      setCanvasStyle: function(prop, value, type) {
        setDataInternal.call(this, 'canvas', prop, value, type);
      },
  
      /*
      Method: setCanvasStyles
  
      Convenience method to set multiple styles at once.
  
      Parameters:
      
      types - (array|string) A set of 'current', 'end' or 'start' values.
      obj - (object) A hash containing the names and values of the properties to be altered.
  
      See also:
      
      <Accessors.setDataset>.
      */
      setCanvasStyles: function(types, obj) {
        types = $.splat(types);
        for(var attr in obj) {
          for(var i=0, val = $.splat(obj[attr]), l=types.length; i<l; i++) {
            this.setCanvasStyle(attr, val[i], types[i]);
          }
        }
      },
  
      /*
      Method: removeCanvasStyle
  
      Remove canvas style properties from data.
  
      Parameters:
      
      A variable number of canvas style strings.
  
      See also:
      
      <Accessors.removeData>.
      */
      removeCanvasStyle: function() {
        removeDataInternal.call(this, 'canvas', Array.prototype.slice.call(arguments));
      },
  
      /*
      Method: getLabelData
  
      Returns the specified label data value property. This is useful for
      querying special/reserved <Graph.Node> label options (i.e.
      dollar prefixed properties that match with $label-<name of label style>).
  
      Parameters:
  
        prop  - (string) The name of the property. The dollar sign prefix is not needed. For
                example *getLabelData(size)* will return *data[$label-size]*.
        type  - (string) The type of the data property queried. Default's *current*. You can access *start* and *end* 
                data properties also.
                
      See also:
      
      <Accessors.getData>.
      */
      getLabelData: function(prop, type, force) {
        return getDataInternal.call(
            this, 'label', prop, type, force, this.Label);
      },
  
      /*
      Method: setLabelData
  
      Sets the current label data with some specific value.
      This method is only useful for reserved (dollar prefixed) properties.
  
      Parameters:
      
      prop - (string) Name of the property. Can be any canvas property like 'shadowBlur', 'shadowColor', 'strokeStyle', etc.
      value - (mixed) The value to set to the property.
      type - (string) Default's *current*. Whether to set *start*, *current* or *end* type properties.
      
      Example:
      
      (start code js)
       node.setLabelData('size', 30);
      (end code)
      
      If we were to make an animation of a node label size then we could do
      
      (start code js)
        var node = viz.getNode('nodeId');
        //set start and end values
        node.setLabelData('size', 10, 'start');
        node.setLabelData('size', 30, 'end');
        //will animate nodes label size
        viz.fx.animate({
          modes: ['label-property:size'],
          duration: 1000
        });
      (end code)
      
      See also:
      
      <Accessors.setData>.
      */
      setLabelData: function(prop, value, type) {
        setDataInternal.call(this, 'label', prop, value, type);
      },
  
      /*
      Method: setLabelDataset
  
      Convenience function to set multiple label data at once.
  
      Parameters:
      
      types - (array|string) A set of 'current', 'end' or 'start' values.
      obj - (object) A hash containing the names and values of the properties to be altered.
  
      See also:
      
      <Accessors.setDataset>.
      */
      setLabelDataset: function(types, obj) {
        types = $.splat(types);
        for(var attr in obj) {
          for(var i=0, val = $.splat(obj[attr]), l=types.length; i<l; i++) {
            this.setLabelData(attr, val[i], types[i]);
          }
        }
      },
  
      /*
      Method: removeLabelData
  
      Remove label properties from data.
      
      Parameters:
      
      A variable number of label property strings.
  
      See also:
      
      <Accessors.removeData>.
      */
      removeLabelData: function() {
        removeDataInternal.call(this, 'label', Array.prototype.slice.call(arguments));
      }
    };
  })();
  
  /*
       Class: Graph.Node
  
       A <Graph> node.
       
       Implements:
       
       <Accessors> methods.
       
       The following <Graph.Util> methods are implemented by <Graph.Node>
       
      - <Graph.Util.eachAdjacency>
      - <Graph.Util.eachLevel>
      - <Graph.Util.eachSubgraph>
      - <Graph.Util.eachSubnode>
      - <Graph.Util.anySubnode>
      - <Graph.Util.getSubnodes>
      - <Graph.Util.getParents>
      - <Graph.Util.isDescendantOf>     
  */
  Graph.Node = new Class({
      
    initialize: function(opt, klass, Node, Edge, Label) {
      var innerOptions = {
        'id': '',
        'name': '',
        'data': {},
        'startData': {},
        'endData': {},
        'adjacencies': {},
  
        'selected': false,
        'drawn': false,
        'exist': false,
  
        'angleSpan': {
          'begin': 0,
          'end' : 0
        },
  
        'pos': new klass,
        'startPos': new klass,
        'endPos': new klass
      };
      
      $.extend(this, $.extend(innerOptions, opt));
      this.Config = this.Node = Node;
      this.Edge = Edge;
      this.Label = Label;
    },
  
      /*
         Method: adjacentTo
      
         Indicates if the node is adjacent to the node specified by id
  
         Parameters:
      
            id - (string) A node id.
      
         Example:
         (start code js)
          node.adjacentTo('nodeId') == true;
         (end code)
      */
      adjacentTo: function(node) {
          return node.id in this.adjacencies;
      },
  
      /*
         Method: getAdjacency
      
         Returns a <Graph.Adjacence> object connecting the current <Graph.Node> and the node having *id* as id.
  
         Parameters:
      
            id - (string) A node id.
      */  
      getAdjacency: function(id) {
          return this.adjacencies[id];
      },
  
      /*
        Method: getPos
     
        Returns the position of the node.
    
        Parameters:
     
           type - (string) Default's *current*. Possible values are "start", "end" or "current".
     
        Returns:
     
          A <Complex> or <Polar> instance.
    
        Example:
        (start code js)
         var pos = node.getPos('end');
        (end code)
     */
     getPos: function(type) {
         type = type || "current";
         if(type == "current") {
           return this.pos;
         } else if(type == "end") {
           return this.endPos;
         } else if(type == "start") {
           return this.startPos;
         }
     },
     /*
       Method: setPos
    
       Sets the node's position.
    
       Parameters:
    
          value - (object) A <Complex> or <Polar> instance.
          type - (string) Default's *current*. Possible values are "start", "end" or "current".
    
       Example:
       (start code js)
        node.setPos(new $jit.Complex(0, 0), 'end');
       (end code)
    */
    setPos: function(value, type) {
        type = type || "current";
        var pos;
        if(type == "current") {
          pos = this.pos;
        } else if(type == "end") {
          pos = this.endPos;
        } else if(type == "start") {
          pos = this.startPos;
        }
        pos.set(value);
    }
  });
  
  Graph.Node.implement(Accessors);
  
  /*
       Class: Graph.Adjacence
  
       A <Graph> adjacence (or edge) connecting two <Graph.Nodes>.
       
       Implements:
       
       <Accessors> methods.
  
       See also:
  
       <Graph>, <Graph.Node>
  
       Properties:
       
        nodeFrom - A <Graph.Node> connected by this edge.
        nodeTo - Another  <Graph.Node> connected by this edge.
        data - Node data property containing a hash (i.e {}) with custom options.
  */
  Graph.Adjacence = new Class({
    
    initialize: function(nodeFrom, nodeTo, data, Edge, Label) {
      this.nodeFrom = nodeFrom;
      this.nodeTo = nodeTo;
      this.data = data || {};
      this.startData = {};
      this.endData = {};
      this.Config = this.Edge = Edge;
      this.Label = Label;
    }
  });
  
  Graph.Adjacence.implement(Accessors);
  
  /*
     Object: Graph.Util
  
     <Graph> traversal and processing utility object.
     
     Note:
     
     For your convenience some of these methods have also been appended to <Graph> and <Graph.Node> classes.
  */
  Graph.Util = {
      /*
         filter
      
         For internal use only. Provides a filtering function based on flags.
      */
      filter: function(param) {
          if(!param || !($.type(param) == 'string')) return function() { return true; };
          var props = param.split(" ");
          return function(elem) {
              for(var i=0; i<props.length; i++) { 
                if(elem[props[i]]) { 
                  return false; 
                }
              }
              return true;
          };
      },
      /*
         Method: getNode
      
         Returns a <Graph.Node> by *id*.
         
         Also implemented by:
         
         <Graph>
  
         Parameters:
  
         graph - (object) A <Graph> instance.
         id - (string) A <Graph.Node> id.
  
         Example:
  
         (start code js)
           $jit.Graph.Util.getNode(graph, 'nodeid');
           //or...
           graph.getNode('nodeid');
         (end code)
      */
      getNode: function(graph, id) {
          return graph.nodes[id];
      },
      
      /*
         Method: eachNode
      
         Iterates over <Graph> nodes performing an *action*.
         
         Also implemented by:
         
         <Graph>.
  
         Parameters:
  
         graph - (object) A <Graph> instance.
         action - (function) A callback function having a <Graph.Node> as first formal parameter.
  
         Example:
         (start code js)
           $jit.Graph.Util.eachNode(graph, function(node) {
            alert(node.name);
           });
           //or...
           graph.eachNode(function(node) {
             alert(node.name);
           });
         (end code)
      */
      eachNode: function(graph, action, flags) {
          var filter = this.filter(flags);
          for(var i in graph.nodes) {
            if(filter(graph.nodes[i])) action(graph.nodes[i]);
          } 
      },
      
      /*
        Method: each
     
        Iterates over <Graph> nodes performing an *action*. It's an alias for <Graph.Util.eachNode>.
        
        Also implemented by:
        
        <Graph>.
    
        Parameters:
    
        graph - (object) A <Graph> instance.
        action - (function) A callback function having a <Graph.Node> as first formal parameter.
    
        Example:
        (start code js)
          $jit.Graph.Util.each(graph, function(node) {
           alert(node.name);
          });
          //or...
          graph.each(function(node) {
            alert(node.name);
          });
        (end code)
     */
     each: function(graph, action, flags) {
        this.eachNode(graph, action, flags); 
     },
  
   /*
         Method: eachAdjacency
      
         Iterates over <Graph.Node> adjacencies applying the *action* function.
         
         Also implemented by:
         
         <Graph.Node>.
  
         Parameters:
  
         node - (object) A <Graph.Node>.
         action - (function) A callback function having <Graph.Adjacence> as first formal parameter.
  
         Example:
         (start code js)
           $jit.Graph.Util.eachAdjacency(node, function(adj) {
            alert(adj.nodeTo.name);
           });
           //or...
           node.eachAdjacency(function(adj) {
             alert(adj.nodeTo.name);
           });
         (end code)
      */
      eachAdjacency: function(node, action, flags) {
          var adj = node.adjacencies, filter = this.filter(flags);
          for(var id in adj) {
            var a = adj[id];
            if(filter(a)) {
              if(a.nodeFrom != node) {
                var tmp = a.nodeFrom;
                a.nodeFrom = a.nodeTo;
                a.nodeTo = tmp;
              }
              action(a, id);
            }
          }
      },
  
       /*
         Method: computeLevels
      
         Performs a BFS traversal setting the correct depth for each node.
          
         Also implemented by:
         
         <Graph>.
         
         Note:
         
         The depth of each node can then be accessed by 
         >node._depth
  
         Parameters:
  
         graph - (object) A <Graph>.
         id - (string) A starting node id for the BFS traversal.
         startDepth - (optional|number) A minimum depth value. Default's 0.
  
      */
      computeLevels: function(graph, id, startDepth, flags) {
          startDepth = startDepth || 0;
          var filter = this.filter(flags);
          this.eachNode(graph, function(elem) {
              elem._flag = false;
              elem._depth = -1;
          }, flags);
          var root = graph.getNode(id);
          root._depth = startDepth;
          var queue = [root];
          while(queue.length != 0) {
              var node = queue.pop();
              node._flag = true;
              this.eachAdjacency(node, function(adj) {
                  var n = adj.nodeTo;
                  if(n._flag == false && filter(n)) {
                      if(n._depth < 0) n._depth = node._depth + 1 + startDepth;
                      queue.unshift(n);
                  }
              }, flags);
          }
      },
  
      /*
         Method: eachBFS
      
         Performs a BFS traversal applying *action* to each <Graph.Node>.
         
         Also implemented by:
         
         <Graph>.
  
         Parameters:
  
         graph - (object) A <Graph>.
         id - (string) A starting node id for the BFS traversal.
         action - (function) A callback function having a <Graph.Node> as first formal parameter.
  
         Example:
         (start code js)
           $jit.Graph.Util.eachBFS(graph, 'mynodeid', function(node) {
            alert(node.name);
           });
           //or...
           graph.eachBFS('mynodeid', function(node) {
             alert(node.name);
           });
         (end code)
      */
      eachBFS: function(graph, id, action, flags) {
          var filter = this.filter(flags);
          this.clean(graph);
          var queue = [graph.getNode(id)];
          while(queue.length != 0) {
              var node = queue.pop();
              if (!node) return;
              node._flag = true;
              action(node, node._depth);
              this.eachAdjacency(node, function(adj) {
                  var n = adj.nodeTo;
                  if(n._flag == false && filter(n)) {
                      n._flag = true;
                      queue.unshift(n);
                  }
              }, flags);
          }
      },
      
      /*
         Method: eachLevel
      
         Iterates over a node's subgraph applying *action* to the nodes of relative depth between *levelBegin* and *levelEnd*.
         In case you need to break the iteration, *action* should return false.
         
         Also implemented by:
         
         <Graph.Node>.
  
         Parameters:
         
         node - (object) A <Graph.Node>.
         levelBegin - (number) A relative level value.
         levelEnd - (number) A relative level value.
         action - (function) A callback function having a <Graph.Node> as first formal parameter.
  
      */
      eachLevel: function(node, levelBegin, levelEnd, action, flags) {
          var d = node._depth, filter = this.filter(flags), that = this, shouldContinue = true;
          levelEnd = levelEnd === false? Number.MAX_VALUE -d : levelEnd;
          (function loopLevel(node, levelBegin, levelEnd) {
              if(!shouldContinue) return;
              var d = node._depth, ret;
              if(d >= levelBegin && d <= levelEnd && filter(node)) ret = action(node, d);
              if(typeof ret !== "undefined") shouldContinue = ret;
              if(shouldContinue && d < levelEnd) {
                  that.eachAdjacency(node, function(adj) {
                      var n = adj.nodeTo;
                      if(n._depth > d) loopLevel(n, levelBegin, levelEnd);
                  });
              }
          })(node, levelBegin + d, levelEnd + d);
      },
  
      /*
         Method: eachSubgraph
      
         Iterates over a node's children recursively.
         
         Also implemented by:
         
         <Graph.Node>.
  
         Parameters:
         node - (object) A <Graph.Node>.
         action - (function) A callback function having a <Graph.Node> as first formal parameter.
  
         Example:
         (start code js)
           $jit.Graph.Util.eachSubgraph(node, function(node) {
             alert(node.name);
           });
           //or...
           node.eachSubgraph(function(node) {
             alert(node.name);
           });
         (end code)
      */
      eachSubgraph: function(node, action, flags) {
        this.eachLevel(node, 0, false, action, flags);
      },
  
      /*
         Method: eachSubnode
      
         Iterates over a node's children (without deeper recursion).
         
         Also implemented by:
         
         <Graph.Node>.
         
         Parameters:
         node - (object) A <Graph.Node>.
         action - (function) A callback function having a <Graph.Node> as first formal parameter.
  
         Example:
         (start code js)
           $jit.Graph.Util.eachSubnode(node, function(node) {
            alert(node.name);
           });
           //or...
           node.eachSubnode(function(node) {
             alert(node.name);
           });
         (end code)
      */
      eachSubnode: function(node, action, flags) {
          this.eachLevel(node, 1, 1, action, flags);
      },
  
      /*
         Method: anySubnode
      
         Returns *true* if any subnode matches the given condition.
         
         Also implemented by:
         
         <Graph.Node>.
  
         Parameters:
         node - (object) A <Graph.Node>.
         cond - (function) A callback function returning a Boolean instance. This function has as first formal parameter a <Graph.Node>.
  
         Example:
         (start code js)
           $jit.Graph.Util.anySubnode(node, function(node) { return node.name == "mynodename"; });
           //or...
           node.anySubnode(function(node) { return node.name == 'mynodename'; });
         (end code)
      */
      anySubnode: function(node, cond, flags) {
        var flag = false;
        cond = cond || $.lambda(true);
        var c = $.type(cond) == 'string'? function(n) { return n[cond]; } : cond;
        this.eachSubnode(node, function(elem) {
          if(c(elem)) flag = true;
        }, flags);
        return flag;
      },
    
      /*
         Method: getSubnodes
      
         Collects all subnodes for a specified node. 
         The *level* parameter filters nodes having relative depth of *level* from the root node. 
         
         Also implemented by:
         
         <Graph.Node>.
  
         Parameters:
         node - (object) A <Graph.Node>.
         level - (optional|number) Default's *0*. A starting relative depth for collecting nodes.
  
         Returns:
         An array of nodes.
  
      */
      getSubnodes: function(node, level, flags) {
          var ans = [], that = this;
          level = level || 0;
          var levelStart, levelEnd;
          if($.type(level) == 'array') {
              levelStart = level[0];
              levelEnd = level[1];
          } else {
              levelStart = level;
              levelEnd = Number.MAX_VALUE - node._depth;
          }
          this.eachLevel(node, levelStart, levelEnd, function(n) {
              ans.push(n);
          }, flags);
          return ans;
      },
    
    
      /*
         Method: getParents
      
         Returns an Array of <Graph.Nodes> which are parents of the given node.
         
         Also implemented by:
         
         <Graph.Node>.
  
         Parameters:
         node - (object) A <Graph.Node>.
  
         Returns:
         An Array of <Graph.Nodes>.
  
         Example:
         (start code js)
           var pars = $jit.Graph.Util.getParents(node);
           //or...
           var pars = node.getParents();
           
           if(pars.length > 0) {
             //do stuff with parents
           }
         (end code)
      */
      getParents: function(node) {
          var ans = [];
          this.eachAdjacency(node, function(adj) {
              var n = adj.nodeTo;
              if(n._depth < node._depth) ans.push(n);
          });
          return ans;
      },
      
      /*
      Method: isDescendantOf
   
      Returns a boolean indicating if some node is descendant of the node with the given id. 
  
      Also implemented by:
      
      <Graph.Node>.
      
      
      Parameters:
      node - (object) A <Graph.Node>.
      id - (string) A <Graph.Node> id.
  
      Example:
      (start code js)
        $jit.Graph.Util.isDescendantOf(node, "nodeid"); //true|false
        //or...
        node.isDescendantOf('nodeid');//true|false
      (end code)
   */
   isDescendantOf: function(node, id) {
      if(node.id == id) return true;
      var pars = this.getParents(node), ans = false;
      for ( var i = 0; !ans && i < pars.length; i++) {
      ans = ans || this.isDescendantOf(pars[i], id);
    }
      return ans;
   },
  
   /*
       Method: clean
    
       Cleans flags from nodes.
  
       Also implemented by:
       
       <Graph>.
       
       Parameters:
       graph - A <Graph> instance.
    */
    clean: function(graph) { this.eachNode(graph, function(elem) { elem._flag = false; }); },
    
    /* 
      Method: getClosestNodeToOrigin 
    
      Returns the closest node to the center of canvas.
    
      Also implemented by:
      
      <Graph>.
      
      Parameters:
     
       graph - (object) A <Graph> instance.
       prop - (optional|string) Default's 'current'. A <Graph.Node> position property. Possible properties are 'start', 'current' or 'end'.
    
    */
    getClosestNodeToOrigin: function(graph, prop, flags) {
     return this.getClosestNodeToPos(graph, Polar.KER, prop, flags);
    },
    
    /* 
      Method: getClosestNodeToPos
    
      Returns the closest node to the given position.
    
      Also implemented by:
      
      <Graph>.
      
      Parameters:
     
       graph - (object) A <Graph> instance.
       pos - (object) A <Complex> or <Polar> instance.
       prop - (optional|string) Default's *current*. A <Graph.Node> position property. Possible properties are 'start', 'current' or 'end'.
    
    */
    getClosestNodeToPos: function(graph, pos, prop, flags) {
     var node = null;
     prop = prop || 'current';
     pos = pos && pos.getc(true) || Complex.KER;
     var distance = function(a, b) {
       var d1 = a.x - b.x, d2 = a.y - b.y;
       return d1 * d1 + d2 * d2;
     };
     this.eachNode(graph, function(elem) {
       node = (node == null || distance(elem.getPos(prop).getc(true), pos) < distance(
           node.getPos(prop).getc(true), pos)) ? elem : node;
     }, flags);
     return node;
    } 
  };
  
  //Append graph methods to <Graph>
  $.each(['get', 'getNode', 'each', 'eachNode', 'computeLevels', 'eachBFS', 'clean', 'getClosestNodeToPos', 'getClosestNodeToOrigin'], function(m) {
    Graph.prototype[m] = function() {
      return Graph.Util[m].apply(Graph.Util, [this].concat(Array.prototype.slice.call(arguments)));
    };
  });
  
  //Append node methods to <Graph.Node>
  $.each(['eachAdjacency', 'eachLevel', 'eachSubgraph', 'eachSubnode', 'anySubnode', 'getSubnodes', 'getParents', 'isDescendantOf'], function(m) {
    Graph.Node.prototype[m] = function() {
      return Graph.Util[m].apply(Graph.Util, [this].concat(Array.prototype.slice.call(arguments)));
    };
  });
  
  /*
   * File: Graph.Op.js
   *
  */
  
  /*
     Object: Graph.Op
  
     Perform <Graph> operations like adding/removing <Graph.Nodes> or <Graph.Adjacences>, 
     morphing a <Graph> into another <Graph>, contracting or expanding subtrees, etc.
  
  */
  Graph.Op = {
  
      options: {
        type: 'nothing',
        duration: 2000,
        hideLabels: true,
        fps:30
      },
      
      initialize: function(viz) {
        this.viz = viz;
      },
  
      /*
         Method: removeNode
      
         Removes one or more <Graph.Nodes> from the visualization. 
         It can also perform several animations like fading sequentially, fading concurrently, iterating or replotting.
  
         Parameters:
      
          node - (string|array) The node's id. Can also be an array having many ids.
          opt - (object) Animation options. It's an object with optional properties described below
          type - (string) Default's *nothing*. Type of the animation. Can be "nothing", "replot", "fade:seq",  "fade:con" or "iter".
          duration - Described in <Options.Fx>.
          fps - Described in <Options.Fx>.
          transition - Described in <Options.Fx>.
          hideLabels - (boolean) Default's *true*. Hide labels during the animation.
     
        Example:
        (start code js)
          var viz = new $jit.Viz(options);
          viz.op.removeNode('nodeId', {
            type: 'fade:seq',
            duration: 1000,
            hideLabels: false,
            transition: $jit.Trans.Quart.easeOut
          });
          //or also
          viz.op.removeNode(['someId', 'otherId'], {
            type: 'fade:con',
            duration: 1500
          });
        (end code)
      */
    
      removeNode: function(node, opt) {
          var viz = this.viz;
          var options = $.merge(this.options, viz.controller, opt);
          var n = $.splat(node);
          var i, that, nodeObj;
          switch(options.type) {
              case 'nothing':
                  for(i=0; i<n.length; i++) {
                      options.onBeforeRemoveNode(viz.graph.getNode(n[i]));
                      viz.graph.removeNode(n[i]);
                  }
                  break;
              
              case 'replot':
                  this.removeNode(n, { type: 'nothing' });
                  viz.labels.clearLabels();
                  viz.refresh(true);
                  break;
              
              case 'fade:seq': case 'fade':
                  that = this;
                  //set alpha to 0 for nodes to remove.
                  for(i=0; i<n.length; i++) {
                      nodeObj = viz.graph.getNode(n[i]);
                      nodeObj.setData('alpha', 0, 'end');
                  }
                  viz.fx.animate($.merge(options, {
                      modes: ['node-property:alpha'],
                      onComplete: function() {
                          that.removeNode(n, { type: 'nothing' });
                          viz.labels.clearLabels();
                          viz.reposition();
                          viz.fx.animate($.merge(options, {
                              modes: ['linear']
                          }));
                      }
                  }));
                  break;
              
              case 'fade:con':
                  that = this;
                  //set alpha to 0 for nodes to remove. Tag them for being ignored on computing positions.
                  for(i=0; i<n.length; i++) {
                      nodeObj = viz.graph.getNode(n[i]);
                      nodeObj.setData('alpha', 0, 'end');
                      nodeObj.ignore = true;
                  }
                  viz.reposition();
                  viz.fx.animate($.merge(options, {
                      modes: ['node-property:alpha', 'linear'],
                      onComplete: function() {
                          that.removeNode(n, { type: 'nothing' });
                          options.onComplete && options.onComplete();
                      }
                  }));
                  break;
              
              case 'iter':
                  that = this;
                  viz.fx.sequence({
                      condition: function() { return n.length != 0; },
                      step: function() { that.removeNode(n.shift(), { type: 'nothing' });  viz.labels.clearLabels(); },
                      onComplete: function() { options.onComplete && options.onComplete(); },
                      duration: Math.ceil(options.duration / n.length)
                  });
                  break;
                  
              default: this.doError();
          }
      },
      
      /*
         Method: removeEdge
      
         Removes one or more <Graph.Adjacences> from the visualization. 
         It can also perform several animations like fading sequentially, fading concurrently, iterating or replotting.
  
         Parameters:
      
         vertex - (array) An array having two strings which are the ids of the nodes connected by this edge (i.e ['id1', 'id2']). Can also be a two dimensional array holding many edges (i.e [['id1', 'id2'], ['id3', 'id4'], ...]).
         opt - (object) Animation options. It's an object with optional properties described below
         type - (string) Default's *nothing*. Type of the animation. Can be "nothing", "replot", "fade:seq",  "fade:con" or "iter".
         duration - Described in <Options.Fx>.
         fps - Described in <Options.Fx>.
         transition - Described in <Options.Fx>.
         hideLabels - (boolean) Default's *true*. Hide labels during the animation.
     
        Example:
        (start code js)
          var viz = new $jit.Viz(options);
          viz.op.removeEdge(['nodeId', 'otherId'], {
            type: 'fade:seq',
            duration: 1000,
            hideLabels: false,
            transition: $jit.Trans.Quart.easeOut
          });
          //or also
          viz.op.removeEdge([['someId', 'otherId'], ['id3', 'id4']], {
            type: 'fade:con',
            duration: 1500
          });
        (end code)
      
      */
      removeEdge: function(vertex, opt) {
          var viz = this.viz;
          var options = $.merge(this.options, viz.controller, opt);
          var v = ($.type(vertex[0]) == 'string')? [vertex] : vertex;
          var i, that, adj;
          switch(options.type) {
              case 'nothing':
                  for(i=0; i<v.length; i++)   viz.graph.removeAdjacence(v[i][0], v[i][1]);
                  break;
              
              case 'replot':
                  this.removeEdge(v, { type: 'nothing' });
                  viz.refresh(true);
                  break;
              
              case 'fade:seq': case 'fade':
                  that = this;
                  //set alpha to 0 for edges to remove.
                  for(i=0; i<v.length; i++) {
                      adj = viz.graph.getAdjacence(v[i][0], v[i][1]);
                      if(adj) {
                          adj.setData('alpha', 0,'end');
                      }
                  }
                  viz.fx.animate($.merge(options, {
                      modes: ['edge-property:alpha'],
                      onComplete: function() {
                          that.removeEdge(v, { type: 'nothing' });
                          viz.reposition();
                          viz.fx.animate($.merge(options, {
                              modes: ['linear']
                          }));
                      }
                  }));
                  break;
              
              case 'fade:con':
                  that = this;
                  //set alpha to 0 for nodes to remove. Tag them for being ignored when computing positions.
                  for(i=0; i<v.length; i++) {
                      adj = viz.graph.getAdjacence(v[i][0], v[i][1]);
                      if(adj) {
                          adj.setData('alpha',0 ,'end');
                          adj.ignore = true;
                      }
                  }
                  viz.reposition();
                  viz.fx.animate($.merge(options, {
                      modes: ['edge-property:alpha', 'linear'],
                      onComplete: function() {
                          that.removeEdge(v, { type: 'nothing' });
                          options.onComplete && options.onComplete();
                      }
                  }));
                  break;
              
              case 'iter':
                  that = this;
                  viz.fx.sequence({
                      condition: function() { return v.length != 0; },
                      step: function() { that.removeEdge(v.shift(), { type: 'nothing' }); viz.labels.clearLabels(); },
                      onComplete: function() { options.onComplete(); },
                      duration: Math.ceil(options.duration / v.length)
                  });
                  break;
                  
              default: this.doError();
          }
      },
      
      /*
         Method: sum
      
         Adds a new graph to the visualization. 
         The JSON graph (or tree) must at least have a common node with the current graph plotted by the visualization. 
         The resulting graph can be defined as follows <http://mathworld.wolfram.com/GraphSum.html>
  
         Parameters:
      
         json - (object) A json tree or graph structure. See also <Loader.loadJSON>.
         opt - (object) Animation options. It's an object with optional properties described below
         type - (string) Default's *nothing*. Type of the animation. Can be "nothing", "replot", "fade:seq",  "fade:con".
         duration - Described in <Options.Fx>.
         fps - Described in <Options.Fx>.
         transition - Described in <Options.Fx>.
         hideLabels - (boolean) Default's *true*. Hide labels during the animation.
     
        Example:
        (start code js)
          //...json contains a tree or graph structure...
  
          var viz = new $jit.Viz(options);
          viz.op.sum(json, {
            type: 'fade:seq',
            duration: 1000,
            hideLabels: false,
            transition: $jit.Trans.Quart.easeOut
          });
          //or also
          viz.op.sum(json, {
            type: 'fade:con',
            duration: 1500
          });
        (end code)
      
      */
      sum: function(json, opt) {
          var viz = this.viz;
          var options = $.merge(this.options, viz.controller, opt), root = viz.root;
          var graph;
          viz.root = opt.id || viz.root;
          switch(options.type) {
              case 'nothing':
                  graph = viz.construct(json);
                  graph.eachNode(function(elem) {
                      elem.eachAdjacency(function(adj) {
                          viz.graph.addAdjacence(adj.nodeFrom, adj.nodeTo, adj.data);
                      });
                  });
                  break;
              
              case 'replot':
                  viz.refresh(true);
                  this.sum(json, { type: 'nothing' });
                  viz.refresh(true);
                  break;
              
              case 'fade:seq': case 'fade': case 'fade:con':
                  that = this;
                  graph = viz.construct(json);
  
                  //set alpha to 0 for nodes to add.
                  var fadeEdges = this.preprocessSum(graph);
                  var modes = !fadeEdges? ['node-property:alpha'] : ['node-property:alpha', 'edge-property:alpha'];
                  viz.reposition();
                  if(options.type != 'fade:con') {
                      viz.fx.animate($.merge(options, {
                          modes: ['linear'],
                          onComplete: function() {
                              viz.fx.animate($.merge(options, {
                                  modes: modes,
                                  onComplete: function() {
                                      options.onComplete();
                                  }
                              }));
                          }
                      }));
                  } else {
                      viz.graph.eachNode(function(elem) {
                          if (elem.id != root && elem.pos.isZero()) {
                            elem.pos.set(elem.endPos); 
                            elem.startPos.set(elem.endPos);
                          }
                      });
                      viz.fx.animate($.merge(options, {
                          modes: ['linear'].concat(modes)
                      }));
                  }
                  break;
  
              default: this.doError();
          }
      },
      
      /*
         Method: morph
      
         This method will transform the current visualized graph into the new JSON representation passed in the method. 
         The JSON object must at least have the root node in common with the current visualized graph.
  
         Parameters:
      
         json - (object) A json tree or graph structure. See also <Loader.loadJSON>.
         opt - (object) Animation options. It's an object with optional properties described below
         type - (string) Default's *nothing*. Type of the animation. Can be "nothing", "replot", "fade:con".
         duration - Described in <Options.Fx>.
         fps - Described in <Options.Fx>.
         transition - Described in <Options.Fx>.
         hideLabels - (boolean) Default's *true*. Hide labels during the animation.
         id - (string) The shared <Graph.Node> id between both graphs.
         
         extraModes - (optional|object) When morphing with an animation, dollar prefixed data parameters are added to 
                      *endData* and not *data* itself. This way you can animate dollar prefixed parameters during your morphing operation. 
                      For animating these extra-parameters you have to specify an object that has animation groups as keys and animation 
                      properties as values, just like specified in <Graph.Plot.animate>.
     
        Example:
        (start code js)
          //...json contains a tree or graph structure...
  
          var viz = new $jit.Viz(options);
          viz.op.morph(json, {
            type: 'fade',
            duration: 1000,
            hideLabels: false,
            transition: $jit.Trans.Quart.easeOut
          });
          //or also
          viz.op.morph(json, {
            type: 'fade',
            duration: 1500
          });
          //if the json data contains dollar prefixed params
          //like $width or $height these too can be animated
          viz.op.morph(json, {
            type: 'fade',
            duration: 1500
          }, {
            'node-property': ['width', 'height']
          });
        (end code)
      
      */
      morph: function(json, opt, extraModes) {
          extraModes = extraModes || {};
          var viz = this.viz;
          var options = $.merge(this.options, viz.controller, opt), root = viz.root;
          var graph;
          //TODO(nico) this hack makes morphing work with the Hypertree. 
          //Need to check if it has been solved and this can be removed.
          viz.root = opt.id || viz.root;
          switch(options.type) {
              case 'nothing':
                  graph = viz.construct(json);
                  graph.eachNode(function(elem) {
                    var nodeExists = viz.graph.hasNode(elem.id);  
                    elem.eachAdjacency(function(adj) {
                      var adjExists = !!viz.graph.getAdjacence(adj.nodeFrom.id, adj.nodeTo.id);
                      viz.graph.addAdjacence(adj.nodeFrom, adj.nodeTo, adj.data);
                      //Update data properties if the node existed
                      if(adjExists) {
                        var addedAdj = viz.graph.getAdjacence(adj.nodeFrom.id, adj.nodeTo.id);
                        for(var prop in (adj.data || {})) {
                          addedAdj.data[prop] = adj.data[prop];
                        }
                      }
                    });
                    //Update data properties if the node existed
                    if(nodeExists) {
                      var addedNode = viz.graph.getNode(elem.id);
                      for(var prop in (elem.data || {})) {
                        addedNode.data[prop] = elem.data[prop];
                      }
                    }
                  });
                  viz.graph.eachNode(function(elem) {
                      elem.eachAdjacency(function(adj) {
                          if(!graph.getAdjacence(adj.nodeFrom.id, adj.nodeTo.id)) {
                              viz.graph.removeAdjacence(adj.nodeFrom.id, adj.nodeTo.id);
                          }
                      });
                      if(!graph.hasNode(elem.id)) viz.graph.removeNode(elem.id);
                  });
                  
                  break;
              
              case 'replot':
                  viz.labels.clearLabels(true);
                  this.morph(json, { type: 'nothing' });
                  viz.refresh(true);
                  viz.refresh(true);
                  break;
                  
              case 'fade:seq': case 'fade': case 'fade:con':
                  that = this;
                  graph = viz.construct(json);
                  //preprocessing for nodes to delete.
                  //get node property modes to interpolate
                  var nodeModes = ('node-property' in extraModes) 
                    && $.map($.splat(extraModes['node-property']), 
                        function(n) { return '$' + n; });
                  viz.graph.eachNode(function(elem) {
                    var graphNode = graph.getNode(elem.id);   
                    if(!graphNode) {
                        elem.setData('alpha', 1);
                        elem.setData('alpha', 1, 'start');
                        elem.setData('alpha', 0, 'end');
                        elem.ignore = true;
                      } else {
                        //Update node data information
                        var graphNodeData = graphNode.data;
                        for(var prop in graphNodeData) {
                          if(nodeModes && ($.indexOf(nodeModes, prop) > -1)) {
                            elem.endData[prop] = graphNodeData[prop];
                          } else {
                            elem.data[prop] = graphNodeData[prop];
                          }
                        }
                      }
                  }); 
                  viz.graph.eachNode(function(elem) {
                      if(elem.ignore) return;
                      elem.eachAdjacency(function(adj) {
                          if(adj.nodeFrom.ignore || adj.nodeTo.ignore) return;
                          var nodeFrom = graph.getNode(adj.nodeFrom.id);
                          var nodeTo = graph.getNode(adj.nodeTo.id);
                          if(!nodeFrom.adjacentTo(nodeTo)) {
                              var adj = viz.graph.getAdjacence(nodeFrom.id, nodeTo.id);
                              fadeEdges = true;
                              adj.setData('alpha', 1);
                              adj.setData('alpha', 1, 'start');
                              adj.setData('alpha', 0, 'end');
                          }
                      });
                  }); 
                  //preprocessing for adding nodes.
                  var fadeEdges = this.preprocessSum(graph);
  
                  var modes = !fadeEdges? ['node-property:alpha'] : 
                                          ['node-property:alpha', 
                                           'edge-property:alpha'];
                  //Append extra node-property animations (if any)
                  modes[0] = modes[0] + (('node-property' in extraModes)? 
                      (':' + $.splat(extraModes['node-property']).join(':')) : '');
                  //Append extra edge-property animations (if any)
                  modes[1] = (modes[1] || 'edge-property:alpha') + (('edge-property' in extraModes)? 
                      (':' + $.splat(extraModes['edge-property']).join(':')) : '');
                  //Add label-property animations (if any)
                  if('label-property' in extraModes) {
                    modes.push('label-property:' + $.splat(extraModes['label-property']).join(':'))
                  }
                  //only use reposition if its implemented.
                  if (viz.reposition) {
                    viz.reposition();
                  } else {
                    viz.compute('end');
                  }
                  viz.graph.eachNode(function(elem) {
                      if (elem.id != root && elem.pos.getp().equals(Polar.KER)) {
                        elem.pos.set(elem.endPos); elem.startPos.set(elem.endPos);
                      }
                  });
                  viz.fx.animate($.merge(options, {
                      modes: [extraModes.position || 'polar'].concat(modes),
                      onComplete: function() {
                          viz.graph.eachNode(function(elem) {
                              if(elem.ignore) viz.graph.removeNode(elem.id);
                          });
                          viz.graph.eachNode(function(elem) {
                              elem.eachAdjacency(function(adj) {
                                  if(adj.ignore) viz.graph.removeAdjacence(adj.nodeFrom.id, adj.nodeTo.id);
                              });
                          });
                          options.onComplete();
                      }
                  }));
                  break;
  
              default:;
          }
      },
  
      
    /*
      Method: contract
   
      Collapses the subtree of the given node. The node will have a _collapsed=true_ property.
      
      Parameters:
   
      node - (object) A <Graph.Node>.
      opt - (object) An object containing options described below
      type - (string) Whether to 'replot' or 'animate' the contraction.
     
      There are also a number of Animation options. For more information see <Options.Fx>.
  
      Example:
      (start code js)
       var viz = new $jit.Viz(options);
       viz.op.contract(node, {
         type: 'animate',
         duration: 1000,
         hideLabels: true,
         transition: $jit.Trans.Quart.easeOut
       });
     (end code)
   
     */
      contract: function(node, opt) {
        var viz = this.viz;
        if(node.collapsed || !node.anySubnode($.lambda(true))) return;
        opt = $.merge(this.options, viz.config, opt || {}, {
          'modes': ['node-property:alpha:span', 'linear']
        });
        node.collapsed = true;
        (function subn(n) {
          n.eachSubnode(function(ch) {
            ch.ignore = true;
            ch.setData('alpha', 0, opt.type == 'animate'? 'end' : 'current');
            subn(ch);
          });
        })(node);
        if(opt.type == 'animate') {
          viz.compute('end');
          if(viz.rotated) {
            viz.rotate(viz.rotated, 'none', {
              'property':'end'
            });
          }
          (function subn(n) {
            n.eachSubnode(function(ch) {
              ch.setPos(node.getPos('end'), 'end');
              subn(ch);
            });
          })(node);
          viz.fx.animate(opt);
        } else if(opt.type == 'replot'){
          viz.refresh();
        }
      },
      
      /*
      Method: expand
   
      Expands the previously contracted subtree. The given node must have the _collapsed=true_ property.
      
      Parameters:
   
      node - (object) A <Graph.Node>.
      opt - (object) An object containing options described below
      type - (string) Whether to 'replot' or 'animate'.
       
      There are also a number of Animation options. For more information see <Options.Fx>.
  
      Example:
      (start code js)
        var viz = new $jit.Viz(options);
        viz.op.expand(node, {
          type: 'animate',
          duration: 1000,
          hideLabels: true,
          transition: $jit.Trans.Quart.easeOut
        });
      (end code)
   
     */
      expand: function(node, opt) {
        if(!('collapsed' in node)) return;
        var viz = this.viz;
        opt = $.merge(this.options, viz.config, opt || {}, {
          'modes': ['node-property:alpha:span', 'linear']
        });
        delete node.collapsed;
        (function subn(n) {
          n.eachSubnode(function(ch) {
            delete ch.ignore;
            ch.setData('alpha', 1, opt.type == 'animate'? 'end' : 'current');
            subn(ch);
          });
        })(node);
        if(opt.type == 'animate') {
          viz.compute('end');
          if(viz.rotated) {
            viz.rotate(viz.rotated, 'none', {
              'property':'end'
            });
          }
          viz.fx.animate(opt);
        } else if(opt.type == 'replot'){
          viz.refresh();
        }
      },
  
      preprocessSum: function(graph) {
          var viz = this.viz;
          graph.eachNode(function(elem) {
              if(!viz.graph.hasNode(elem.id)) {
                  viz.graph.addNode(elem);
                  var n = viz.graph.getNode(elem.id);
                  n.setData('alpha', 0);
                  n.setData('alpha', 0, 'start');
                  n.setData('alpha', 1, 'end');
              }
          }); 
          var fadeEdges = false;
          graph.eachNode(function(elem) {
              elem.eachAdjacency(function(adj) {
                  var nodeFrom = viz.graph.getNode(adj.nodeFrom.id);
                  var nodeTo = viz.graph.getNode(adj.nodeTo.id);
                  if(!nodeFrom.adjacentTo(nodeTo)) {
                      var adj = viz.graph.addAdjacence(nodeFrom, nodeTo, adj.data);
                      if(nodeFrom.startAlpha == nodeFrom.endAlpha 
                      && nodeTo.startAlpha == nodeTo.endAlpha) {
                          fadeEdges = true;
                          adj.setData('alpha', 0);
                          adj.setData('alpha', 0, 'start');
                          adj.setData('alpha', 1, 'end');
                      } 
                  }
              });
          }); 
          return fadeEdges;
      }
  };
  
  
  
  /*
     File: Helpers.js
   
     Helpers are objects that contain rendering primitives (like rectangles, ellipses, etc), for plotting nodes and edges.
     Helpers also contain implementations of the *contains* method, a method returning a boolean indicating whether the mouse
     position is over the rendered shape.
     
     Helpers are very useful when implementing new NodeTypes, since you can access them through *this.nodeHelper* and 
     *this.edgeHelper* <Graph.Plot> properties, providing you with simple primitives and mouse-position check functions.
     
     Example:
     (start code js)
     //implement a new node type
     $jit.Viz.Plot.NodeTypes.implement({
       'customNodeType': {
         'render': function(node, canvas) {
           this.nodeHelper.circle.render ...
         },
         'contains': function(node, pos) {
           this.nodeHelper.circle.contains ...
         }
       }
     });
     //implement an edge type
     $jit.Viz.Plot.EdgeTypes.implement({
       'customNodeType': {
         'render': function(node, canvas) {
           this.edgeHelper.circle.render ...
         },
         //optional
         'contains': function(node, pos) {
           this.edgeHelper.circle.contains ...
         }
       }
     });
     (end code)
  
  */
  
  /*
     Object: NodeHelper
     
     Contains rendering and other type of primitives for simple shapes.
   */
  var NodeHelper = {
    'none': {
      'render': $.empty,
      'contains': $.lambda(false)
    },
    /*
     Object: NodeHelper.circle
     */
    'circle': {
      /*
       Method: render
       
       Renders a circle into the canvas.
       
       Parameters:
       
       type - (string) Possible options are 'fill' or 'stroke'.
       pos - (object) An *x*, *y* object with the position of the center of the circle.
       radius - (number) The radius of the circle to be rendered.
       canvas - (object) A <Canvas> instance.
       
       Example:
       (start code js)
       NodeHelper.circle.render('fill', { x: 10, y: 30 }, 30, viz.canvas);
       (end code)
       */
      'render': function(type, pos, radius, canvas){
        var ctx = canvas.getCtx();
        ctx.beginPath();
        ctx.arc(pos.x, pos.y, radius, 0, Math.PI * 2, true);
        ctx.closePath();
        ctx[type]();
      },
      /*
      Method: contains
      
      Returns *true* if *pos* is contained in the area of the shape. Returns *false* otherwise.
      
      Parameters:
      
      npos - (object) An *x*, *y* object with the <Graph.Node> position.
      pos - (object) An *x*, *y* object with the position to check.
      radius - (number) The radius of the rendered circle.
      
      Example:
      (start code js)
      NodeHelper.circle.contains({ x: 10, y: 30 }, { x: 15, y: 35 }, 30); //true
      (end code)
      */
      'contains': function(npos, pos, radius){
        var diffx = npos.x - pos.x, 
            diffy = npos.y - pos.y, 
            diff = diffx * diffx + diffy * diffy;
        return diff <= radius * radius;
      }
    },
    /*
    Object: NodeHelper.ellipse
    */
    'ellipse': {
      /*
      Method: render
      
      Renders an ellipse into the canvas.
      
      Parameters:
      
      type - (string) Possible options are 'fill' or 'stroke'.
      pos - (object) An *x*, *y* object with the position of the center of the ellipse.
      width - (number) The width of the ellipse.
      height - (number) The height of the ellipse.
      canvas - (object) A <Canvas> instance.
      
      Example:
      (start code js)
      NodeHelper.ellipse.render('fill', { x: 10, y: 30 }, 30, 40, viz.canvas);
      (end code)
      */
      'render': function(type, pos, width, height, canvas){
        var ctx = canvas.getCtx(),
            scalex = 1,
            scaley = 1,
            scaleposx = 1,
            scaleposy = 1,
            radius = 0;
  
        if (width > height) {
            radius = width / 2;
            scaley = height / width;
            scaleposy = width / height;
        } else {
            radius = height / 2;
            scalex = width / height;
            scaleposx = height / width;
        }
  
        ctx.save();
        ctx.scale(scalex, scaley);
        ctx.beginPath();
        ctx.arc(pos.x * scaleposx, pos.y * scaleposy, radius, 0, Math.PI * 2, true);
        ctx.closePath();
        ctx[type]();
        ctx.restore();
      },
      /*
      Method: contains
      
      Returns *true* if *pos* is contained in the area of the shape. Returns *false* otherwise.
      
      Parameters:
      
      npos - (object) An *x*, *y* object with the <Graph.Node> position.
      pos - (object) An *x*, *y* object with the position to check.
      width - (number) The width of the rendered ellipse.
      height - (number) The height of the rendered ellipse.
      
      Example:
      (start code js)
      NodeHelper.ellipse.contains({ x: 10, y: 30 }, { x: 15, y: 35 }, 30, 40);
      (end code)
      */
      'contains': function(npos, pos, width, height){
        var radius = 0,
            scalex = 1,
            scaley = 1,
            diffx = 0,
            diffy = 0,
            diff = 0;
  
        if (width > height) {
  	      radius = width / 2;
  	      scaley = height / width;
        } else {
            radius = height / 2;
            scalex = width / height;
        }
  
        diffx = (npos.x - pos.x) * (1 / scalex);
        diffy = (npos.y - pos.y) * (1 / scaley);
        diff = diffx * diffx + diffy * diffy;
        return diff <= radius * radius;
      }
    },
    /*
    Object: NodeHelper.square
    */
    'square': {
      /*
      Method: render
      
      Renders a square into the canvas.
      
      Parameters:
      
      type - (string) Possible options are 'fill' or 'stroke'.
      pos - (object) An *x*, *y* object with the position of the center of the square.
      dim - (number) The radius (or half-diameter) of the square.
      canvas - (object) A <Canvas> instance.
      
      Example:
      (start code js)
      NodeHelper.square.render('stroke', { x: 10, y: 30 }, 40, viz.canvas);
      (end code)
      */
      'render': function(type, pos, dim, canvas){
        canvas.getCtx()[type + "Rect"](pos.x - dim, pos.y - dim, 2*dim, 2*dim);
      },
      /*
      Method: contains
      
      Returns *true* if *pos* is contained in the area of the shape. Returns *false* otherwise.
      
      Parameters:
      
      npos - (object) An *x*, *y* object with the <Graph.Node> position.
      pos - (object) An *x*, *y* object with the position to check.
      dim - (number) The radius (or half-diameter) of the square.
      
      Example:
      (start code js)
      NodeHelper.square.contains({ x: 10, y: 30 }, { x: 15, y: 35 }, 30);
      (end code)
      */
      'contains': function(npos, pos, dim){
        return Math.abs(pos.x - npos.x) <= dim && Math.abs(pos.y - npos.y) <= dim;
      }
    },
    /*
    Object: NodeHelper.rectangle
    */
    'rectangle': {
      /*
      Method: render
      
      Renders a rectangle into the canvas.
      
      Parameters:
      
      type - (string) Possible options are 'fill' or 'stroke'.
      pos - (object) An *x*, *y* object with the position of the center of the rectangle.
      width - (number) The width of the rectangle.
      height - (number) The height of the rectangle.
      canvas - (object) A <Canvas> instance.
      
      Example:
      (start code js)
      NodeHelper.rectangle.render('fill', { x: 10, y: 30 }, 30, 40, viz.canvas);
      (end code)
      */
      'render': function(type, pos, width, height, canvas){
        canvas.getCtx()[type + "Rect"](pos.x - width / 2, pos.y - height / 2, 
                                        width, height);
      },
      /*
      Method: contains
      
      Returns *true* if *pos* is contained in the area of the shape. Returns *false* otherwise.
      
      Parameters:
      
      npos - (object) An *x*, *y* object with the <Graph.Node> position.
      pos - (object) An *x*, *y* object with the position to check.
      width - (number) The width of the rendered rectangle.
      height - (number) The height of the rendered rectangle.
      
      Example:
      (start code js)
      NodeHelper.rectangle.contains({ x: 10, y: 30 }, { x: 15, y: 35 }, 30, 40);
      (end code)
      */
      'contains': function(npos, pos, width, height){
        return Math.abs(pos.x - npos.x) <= width / 2
            && Math.abs(pos.y - npos.y) <= height / 2;
      }
    },
    /*
    Object: NodeHelper.triangle
    */
    'triangle': {
      /*
      Method: render
      
      Renders a triangle into the canvas.
      
      Parameters:
      
      type - (string) Possible options are 'fill' or 'stroke'.
      pos - (object) An *x*, *y* object with the position of the center of the triangle.
      dim - (number) Half the base and half the height of the triangle.
      canvas - (object) A <Canvas> instance.
      
      Example:
      (start code js)
      NodeHelper.triangle.render('stroke', { x: 10, y: 30 }, 40, viz.canvas);
      (end code)
      */
      'render': function(type, pos, dim, canvas){
        var ctx = canvas.getCtx(), 
            c1x = pos.x, 
            c1y = pos.y - dim, 
            c2x = c1x - dim, 
            c2y = pos.y + dim, 
            c3x = c1x + dim, 
            c3y = c2y;
        ctx.beginPath();
        ctx.moveTo(c1x, c1y);
        ctx.lineTo(c2x, c2y);
        ctx.lineTo(c3x, c3y);
        ctx.closePath();
        ctx[type]();
      },
      /*
      Method: contains
      
      Returns *true* if *pos* is contained in the area of the shape. Returns *false* otherwise.
      
      Parameters:
      
      npos - (object) An *x*, *y* object with the <Graph.Node> position.
      pos - (object) An *x*, *y* object with the position to check.
      dim - (number) Half the base and half the height of the triangle.
      
      Example:
      (start code js)
      NodeHelper.triangle.contains({ x: 10, y: 30 }, { x: 15, y: 35 }, 30);
      (end code)
      */
      'contains': function(npos, pos, dim) {
        return NodeHelper.circle.contains(npos, pos, dim);
      }
    },
    /*
    Object: NodeHelper.star
    */
    'star': {
      /*
      Method: render
      
      Renders a star (concave decagon) into the canvas.
      
      Parameters:
      
      type - (string) Possible options are 'fill' or 'stroke'.
      pos - (object) An *x*, *y* object with the position of the center of the star.
      dim - (number) The length of a side of a concave decagon.
      canvas - (object) A <Canvas> instance.
      
      Example:
      (start code js)
      NodeHelper.star.render('stroke', { x: 10, y: 30 }, 40, viz.canvas);
      (end code)
      */
      'render': function(type, pos, dim, canvas){
        var ctx = canvas.getCtx(), 
            pi5 = Math.PI / 5;
        ctx.save();
        ctx.translate(pos.x, pos.y);
        ctx.beginPath();
        ctx.moveTo(dim, 0);
        for (var i = 0; i < 9; i++) {
          ctx.rotate(pi5);
          if (i % 2 == 0) {
            ctx.lineTo((dim / 0.525731) * 0.200811, 0);
          } else {
            ctx.lineTo(dim, 0);
          }
        }
        ctx.closePath();
        ctx[type]();
        ctx.restore();
      },
      /*
      Method: contains
      
      Returns *true* if *pos* is contained in the area of the shape. Returns *false* otherwise.
      
      Parameters:
      
      npos - (object) An *x*, *y* object with the <Graph.Node> position.
      pos - (object) An *x*, *y* object with the position to check.
      dim - (number) The length of a side of a concave decagon.
      
      Example:
      (start code js)
      NodeHelper.star.contains({ x: 10, y: 30 }, { x: 15, y: 35 }, 30);
      (end code)
      */
      'contains': function(npos, pos, dim) {
        return NodeHelper.circle.contains(npos, pos, dim);
      }
    }
  };
  
  /*
    Object: EdgeHelper
    
    Contains rendering primitives for simple edge shapes.
  */
  var EdgeHelper = {
    /*
      Object: EdgeHelper.line
    */
    'line': {
        /*
        Method: render
        
        Renders a line into the canvas.
        
        Parameters:
        
        from - (object) An *x*, *y* object with the starting position of the line.
        to - (object) An *x*, *y* object with the ending position of the line.
        canvas - (object) A <Canvas> instance.
        
        Example:
        (start code js)
        EdgeHelper.line.render({ x: 10, y: 30 }, { x: 10, y: 50 }, viz.canvas);
        (end code)
        */
        'render': function(from, to, canvas){
          var ctx = canvas.getCtx();
          ctx.beginPath();
          ctx.moveTo(from.x, from.y);
          ctx.lineTo(to.x, to.y);
          ctx.stroke();
        },
        /*
        Method: contains
        
        Returns *true* if *pos* is contained in the area of the shape. Returns *false* otherwise.
        
        Parameters:
        
        posFrom - (object) An *x*, *y* object with a <Graph.Node> position.
        posTo - (object) An *x*, *y* object with a <Graph.Node> position.
        pos - (object) An *x*, *y* object with the position to check.
        epsilon - (number) The dimension of the shape.
        
        Example:
        (start code js)
        EdgeHelper.line.contains({ x: 10, y: 30 }, { x: 15, y: 35 }, { x: 15, y: 35 }, 30);
        (end code)
        */
        'contains': function(posFrom, posTo, pos, epsilon) {
          var min = Math.min, 
              max = Math.max,
              minPosX = min(posFrom.x, posTo.x),
              maxPosX = max(posFrom.x, posTo.x),
              minPosY = min(posFrom.y, posTo.y),
              maxPosY = max(posFrom.y, posTo.y);
          
          if(pos.x >= minPosX && pos.x <= maxPosX 
              && pos.y >= minPosY && pos.y <= maxPosY) {
            if(Math.abs(posTo.x - posFrom.x) <= epsilon) {
              return true;
            }
            var dist = (posTo.y - posFrom.y) / (posTo.x - posFrom.x) * (pos.x - posFrom.x) + posFrom.y;
            return Math.abs(dist - pos.y) <= epsilon;
          }
          return false;
        }
      },
    /*
      Object: EdgeHelper.arrow
    */
    'arrow': {
        /*
        Method: render
        
        Renders an arrow into the canvas.
        
        Parameters:
        
        from - (object) An *x*, *y* object with the starting position of the arrow.
        to - (object) An *x*, *y* object with the ending position of the arrow.
        dim - (number) The dimension of the arrow.
        swap - (boolean) Whether to set the arrow pointing to the starting position or the ending position.
        canvas - (object) A <Canvas> instance.
        
        Example:
        (start code js)
        EdgeHelper.arrow.render({ x: 10, y: 30 }, { x: 10, y: 50 }, 13, false, viz.canvas);
        (end code)
        */
      'render': function(from, to, dim, swap, canvas){
          var ctx = canvas.getCtx();
          // invert edge direction
          if (swap) {
            var tmp = from;
            from = to;
            to = tmp;
          }
          var vect = new Complex(to.x - from.x, to.y - from.y);
          vect.$scale(dim / vect.norm());
          var intermediatePoint = new Complex(to.x - vect.x, to.y - vect.y),
              normal = new Complex(-vect.y / 2, vect.x / 2),
              v1 = intermediatePoint.add(normal), 
              v2 = intermediatePoint.$add(normal.$scale(-1));
          
          ctx.beginPath();
          ctx.moveTo(from.x, from.y);
          ctx.lineTo(to.x, to.y);
          ctx.stroke();
          ctx.beginPath();
          ctx.moveTo(v1.x, v1.y);
          ctx.lineTo(v2.x, v2.y);
          ctx.lineTo(to.x, to.y);
          ctx.closePath();
          ctx.fill();
      },
      /*
      Method: contains
      
      Returns *true* if *pos* is contained in the area of the shape. Returns *false* otherwise.
      
      Parameters:
      
      posFrom - (object) An *x*, *y* object with a <Graph.Node> position.
      posTo - (object) An *x*, *y* object with a <Graph.Node> position.
      pos - (object) An *x*, *y* object with the position to check.
      epsilon - (number) The dimension of the shape.
      
      Example:
      (start code js)
      EdgeHelper.arrow.contains({ x: 10, y: 30 }, { x: 15, y: 35 }, { x: 15, y: 35 }, 30);
      (end code)
      */
      'contains': function(posFrom, posTo, pos, epsilon) {
        return EdgeHelper.line.contains(posFrom, posTo, pos, epsilon);
      }
    },
    /*
      Object: EdgeHelper.hyperline
    */
    'hyperline': {
      /*
      Method: render
      
      Renders a hyperline into the canvas. A hyperline are the lines drawn for the <Hypertree> visualization.
      
      Parameters:
      
      from - (object) An *x*, *y* object with the starting position of the hyperline. *x* and *y* must belong to [0, 1).
      to - (object) An *x*, *y* object with the ending position of the hyperline. *x* and *y* must belong to [0, 1).
      r - (number) The scaling factor.
      canvas - (object) A <Canvas> instance.
      
      Example:
      (start code js)
      EdgeHelper.hyperline.render({ x: 10, y: 30 }, { x: 10, y: 50 }, 100, viz.canvas);
      (end code)
      */
      'render': function(from, to, r, canvas){
        var ctx = canvas.getCtx();  
        var centerOfCircle = computeArcThroughTwoPoints(from, to);
        if (centerOfCircle.a > 1000 || centerOfCircle.b > 1000
            || centerOfCircle.ratio < 0) {
          ctx.beginPath();
          ctx.moveTo(from.x * r, from.y * r);
          ctx.lineTo(to.x * r, to.y * r);
          ctx.stroke();
        } else {
          var angleBegin = Math.atan2(to.y - centerOfCircle.y, to.x
              - centerOfCircle.x);
          var angleEnd = Math.atan2(from.y - centerOfCircle.y, from.x
              - centerOfCircle.x);
          var sense = sense(angleBegin, angleEnd);
          ctx.beginPath();
          ctx.arc(centerOfCircle.x * r, centerOfCircle.y * r, centerOfCircle.ratio
              * r, angleBegin, angleEnd, sense);
          ctx.stroke();
        }
        /*      
          Calculates the arc parameters through two points.
          
          More information in <http://en.wikipedia.org/wiki/Poincar%C3%A9_disc_model#Analytic_geometry_constructions_in_the_hyperbolic_plane> 
        
          Parameters:
        
          p1 - A <Complex> instance.
          p2 - A <Complex> instance.
          scale - The Disk's diameter.
        
          Returns:
        
          An object containing some arc properties.
        */
        function computeArcThroughTwoPoints(p1, p2){
          var aDen = (p1.x * p2.y - p1.y * p2.x), bDen = aDen;
          var sq1 = p1.squaredNorm(), sq2 = p2.squaredNorm();
          // Fall back to a straight line
          if (aDen == 0)
            return {
              x: 0,
              y: 0,
              ratio: -1
            };
      
          var a = (p1.y * sq2 - p2.y * sq1 + p1.y - p2.y) / aDen;
          var b = (p2.x * sq1 - p1.x * sq2 + p2.x - p1.x) / bDen;
          var x = -a / 2;
          var y = -b / 2;
          var squaredRatio = (a * a + b * b) / 4 - 1;
          // Fall back to a straight line
          if (squaredRatio < 0)
            return {
              x: 0,
              y: 0,
              ratio: -1
            };
          var ratio = Math.sqrt(squaredRatio);
          var out = {
            x: x,
            y: y,
            ratio: ratio > 1000? -1 : ratio,
            a: a,
            b: b
          };
      
          return out;
        }
        /*      
          Sets angle direction to clockwise (true) or counterclockwise (false). 
           
          Parameters: 
        
             angleBegin - Starting angle for drawing the arc. 
             angleEnd - The HyperLine will be drawn from angleBegin to angleEnd. 
        
          Returns: 
        
             A Boolean instance describing the sense for drawing the HyperLine. 
        */
        function sense(angleBegin, angleEnd){
          return (angleBegin < angleEnd)? ((angleBegin + Math.PI > angleEnd)? false
              : true) : ((angleEnd + Math.PI > angleBegin)? true : false);
        }
      },
      /*
      Method: contains
      
      Not Implemented
      
      Returns *true* if *pos* is contained in the area of the shape. Returns *false* otherwise.
      
      Parameters:
      
      posFrom - (object) An *x*, *y* object with a <Graph.Node> position.
      posTo - (object) An *x*, *y* object with a <Graph.Node> position.
      pos - (object) An *x*, *y* object with the position to check.
      epsilon - (number) The dimension of the shape.
      
      Example:
      (start code js)
      EdgeHelper.hyperline.contains({ x: 10, y: 30 }, { x: 15, y: 35 }, { x: 15, y: 35 }, 30);
      (end code)
      */
      'contains': $.lambda(false)
    }
  };
  
  
  	/*
   * File: Graph.Plot.js
   */
  
  /*
     Object: Graph.Plot
  
     <Graph> rendering and animation methods.
     
     Properties:
     
     nodeHelper - <NodeHelper> object.
     edgeHelper - <EdgeHelper> object.
  */
  Graph.Plot = {
      //Default initializer
      initialize: function(viz, klass){
        this.viz = viz;
        this.config = viz.config;
        this.node = viz.config.Node;
        this.edge = viz.config.Edge;
        this.animation = new Animation;
        this.nodeTypes = new klass.Plot.NodeTypes;
        this.edgeTypes = new klass.Plot.EdgeTypes;
        this.labels = viz.labels;
     },
  
      //Add helpers
      nodeHelper: NodeHelper,
      edgeHelper: EdgeHelper,
      
      Interpolator: {
          //node/edge property parsers
          'map': {
            'border': 'color',
            'color': 'color',
            'width': 'number',
            'height': 'number',
            'dim': 'number',
            'alpha': 'number',
            'lineWidth': 'number',
            'angularWidth':'number',
            'span':'number',
            'valueArray':'array-number',
            'dimArray':'array-number',
            'vertices':'polygon'
            //'colorArray':'array-color'
          },
  
          //canvas specific parsers
          'canvas': {
            'globalAlpha': 'number',
            'fillStyle': 'color',
            'strokeStyle': 'color',
            'lineWidth': 'number',
            'shadowBlur': 'number',
            'shadowColor': 'color',
            'shadowOffsetX': 'number',
            'shadowOffsetY': 'number',
            'miterLimit': 'number'
          },
  
          //label parsers
          'label': {
            'size': 'number',
            'color': 'color'
          },
  
          //Number interpolator
          'compute': function(from, to, delta) {
            return from + (to - from) * delta;
          },
  
          //Position interpolators
          'moebius': function(elem, props, delta, vector) {
            var v = vector.scale(-delta);
            if(v.norm() < 1) {
                var x = v.x, y = v.y;
                var ans = elem.startPos
                  .getc().moebiusTransformation(v);
                elem.pos.setc(ans.x, ans.y);
                v.x = x; v.y = y;
              }
          },
  
          'linear': function(elem, props, delta) {
              var from = elem.startPos.getc(true);
              var to = elem.endPos.getc(true);
              elem.pos.setc(this.compute(from.x, to.x, delta),
                            this.compute(from.y, to.y, delta));
          },
  
          'polar': function(elem, props, delta) {
            var from = elem.startPos.getp(true);
            var to = elem.endPos.getp();
            var ans = to.interpolate(from, delta);
            elem.pos.setp(ans.theta, ans.rho);
          },
  
          //Graph's Node/Edge interpolators
          'number': function(elem, prop, delta, getter, setter) {
            var from = elem[getter](prop, 'start');
            var to = elem[getter](prop, 'end');
            elem[setter](prop, this.compute(from, to, delta));
          },
  
          'color': function(elem, prop, delta, getter, setter) {
            var from = $.hexToRgb(elem[getter](prop, 'start'));
            var to = $.hexToRgb(elem[getter](prop, 'end'));
            var comp = this.compute;
            var val = $.rgbToHex([parseInt(comp(from[0], to[0], delta)),
                                  parseInt(comp(from[1], to[1], delta)),
                                  parseInt(comp(from[2], to[2], delta))]);
  
            elem[setter](prop, val);
          },
  
          'array-number': function(elem, prop, delta, getter, setter) {
            var from = elem[getter](prop, 'start'),
                to = elem[getter](prop, 'end'),
                cur = [];
            for(var i=0, l=from.length; i<l; i++) {
              var fromi = from[i], toi = to[i];
              if(fromi.length) {
                for(var j=0, len=fromi.length, curi=[]; j<len; j++) {
                  curi.push(this.compute(fromi[j], toi[j], delta));
                }
                cur.push(curi);
              } else {
                cur.push(this.compute(fromi, toi, delta));
              }
            }
            elem[setter](prop, cur);
          },
  
          'node': function(elem, props, delta, map, getter, setter) {
            map = this[map];
            if(props) {
              var len = props.length;
              for(var i=0; i<len; i++) {
                var pi = props[i];
                this[map[pi]](elem, pi, delta, getter, setter);
              }
            } else {
              for(var pi in map) {
                this[map[pi]](elem, pi, delta, getter, setter);
              }
            }
          },
  
          'edge': function(elem, props, delta, mapKey, getter, setter) {
              var adjs = elem.adjacencies;
              for(var id in adjs) this['node'](adjs[id], props, delta, mapKey, getter, setter);
          },
  
          'node-property': function(elem, props, delta) {
            this['node'](elem, props, delta, 'map', 'getData', 'setData');
          },
  
          'edge-property': function(elem, props, delta) {
            this['edge'](elem, props, delta, 'map', 'getData', 'setData');
          },
  
          'label-property': function(elem, props, delta) {
            this['node'](elem, props, delta, 'label', 'getLabelData', 'setLabelData');
          },
  
          'node-style': function(elem, props, delta) {
            this['node'](elem, props, delta, 'canvas', 'getCanvasStyle', 'setCanvasStyle');
          },
  
          'edge-style': function(elem, props, delta) {
            this['edge'](elem, props, delta, 'canvas', 'getCanvasStyle', 'setCanvasStyle');
          },
  
          'polygon': function(elem, prop, delta, getter, setter) {
            var from = elem[getter](prop, 'start'),
                to = elem[getter](prop, 'end'),
                cur = [];
            if (typeof from.offset == 'undefined') {
              if (from === 0) {
                from = $.map(to, function() {
                  return new $jit.Complex(0, 0);
                });
                from.offset = 0;
              }
              else {
                if (from.length == 0) {
                  from.push(new $jit.Complex(0, 0));
                }
                while (from.length < to.length) {
                  from.push(from[0]);
                }
                while (from.length > to.length) {
                  to.push(to[0] || new $jit.Complex(0, 0));
                }
                if (from.length == 0) return;
                var l = from.length;
                var minDist = 1e300;
                for (var offset = 0; offset < l; offset ++) {
                  var d = 0;
                  for (var i = 0; i < l; i++) {
                    d +=Geometry.dist2(from[(offset + i) % l], to[i]);
                  }
                  if (d < minDist) {
                    from.offset = offset;
                    minDist = d;
                  }
                }
              }
            }
  
            for (var i = 0, l = from.length; i < l; i++) {
              var fromi = from[(i + from.offset) % l], toi = to[i];
              cur.push(new $jit.Complex(
                  this.compute(fromi.x, toi.x, delta),
                  this.compute(fromi.y, toi.y, delta)
              ));
            }
            elem[setter](prop, cur);
          }
      },
      
    
      /*
         sequence
      
         Iteratively performs an action while refreshing the state of the visualization.
  
         Parameters:
  
         options - (object) An object containing some sequence options described below
         condition - (function) A function returning a boolean instance in order to stop iterations.
         step - (function) A function to execute on each step of the iteration.
         onComplete - (function) A function to execute when the sequence finishes.
         duration - (number) Duration (in milliseconds) of each step.
  
        Example:
         (start code js)
          var rg = new $jit.RGraph(options);
          var i = 0;
          rg.fx.sequence({
            condition: function() {
             return i == 10;
            },
            step: function() {
              alert(i++);
            },
            onComplete: function() {
             alert('done!');
            }
          });
         (end code)
  
      */
      sequence: function(options) {
          var that = this;
          options = $.merge({
            condition: $.lambda(false),
            step: $.empty,
            onComplete: $.empty,
            duration: 200
          }, options || {});
  
          var interval = setInterval(function() {
            if(options.condition()) {
              options.step();
            } else {
              clearInterval(interval);
              options.onComplete();
            }
            that.viz.refresh(true);
          }, options.duration);
      },
      
      /*
        prepare
   
        Prepare graph position and other attribute values before performing an Animation. 
        This method is used internally by the Toolkit.
        
        See also:
         
         <Animation>, <Graph.Plot.animate>
  
      */
      prepare: function(modes) {
        var graph = this.viz.graph,
            accessors = {
              'node-property': {
                'getter': 'getData',
                'setter': 'setData'
              },
              'edge-property': {
                'getter': 'getData',
                'setter': 'setData'
              },
              'node-style': {
                'getter': 'getCanvasStyle',
                'setter': 'setCanvasStyle'
              },
              'edge-style': {
                'getter': 'getCanvasStyle',
                'setter': 'setCanvasStyle'
              }
            };
  
        //parse modes
        var m = {};
        if($.type(modes) == 'array') {
          for(var i=0, len=modes.length; i < len; i++) {
            var elems = modes[i].split(':');
            m[elems.shift()] = elems;
          }
        } else {
          for(var p in modes) {
            if(p == 'position') {
              m[modes.position] = [];
            } else {
              m[p] = $.splat(modes[p]);
            }
          }
        }
        
        graph.eachNode(function(node) { 
          node.startPos.set(node.pos);
          $.each(['node-property', 'node-style'], function(p) {
            if(p in m) {
              var prop = m[p];
              for(var i=0, l=prop.length; i < l; i++) {
                node[accessors[p].setter](prop[i], node[accessors[p].getter](prop[i]), 'start');
              }
            }
          });
          $.each(['edge-property', 'edge-style'], function(p) {
            if(p in m) {
              var prop = m[p];
              node.eachAdjacency(function(adj) {
                for(var i=0, l=prop.length; i < l; i++) {
                  adj[accessors[p].setter](prop[i], adj[accessors[p].getter](prop[i]), 'start');
                }
              });
            }
          });
        });
        return m;
      },
      
      /*
         Method: animate
      
         Animates a <Graph> by interpolating some <Graph.Node>, <Graph.Adjacence> or <Graph.Label> properties.
  
         Parameters:
  
         opt - (object) Animation options. The object properties are described below
         duration - (optional) Described in <Options.Fx>.
         fps - (optional) Described in <Options.Fx>.
         hideLabels - (optional|boolean) Whether to hide labels during the animation.
         modes - (required|object) An object with animation modes (described below).
  
         Animation modes:
         
         Animation modes are strings representing different node/edge and graph properties that you'd like to animate. 
         They are represented by an object that has as keys main categories of properties to animate and as values a list 
         of these specific properties. The properties are described below
         
         position - Describes the way nodes' positions must be interpolated. Possible values are 'linear', 'polar' or 'moebius'.
         node-property - Describes which Node properties will be interpolated. These properties can be any of the ones defined in <Options.Node>.
         edge-property - Describes which Edge properties will be interpolated. These properties can be any the ones defined in <Options.Edge>.
         label-property - Describes which Label properties will be interpolated. These properties can be any of the ones defined in <Options.Label> like color or size.
         node-style - Describes which Node Canvas Styles will be interpolated. These are specific canvas properties like fillStyle, strokeStyle, lineWidth, shadowBlur, shadowColor, shadowOffsetX, shadowOffsetY, etc.
         edge-style - Describes which Edge Canvas Styles will be interpolated. These are specific canvas properties like fillStyle, strokeStyle, lineWidth, shadowBlur, shadowColor, shadowOffsetX, shadowOffsetY, etc.
  
         Example:
         (start code js)
         var viz = new $jit.Viz(options);
         //...tweak some Data, CanvasStyles or LabelData properties...
         viz.fx.animate({
           modes: {
             'position': 'linear',
             'node-property': ['width', 'height'],
             'node-style': 'shadowColor',
             'label-property': 'size'
           },
           hideLabels: false
         });
         //...can also be written like this...
         viz.fx.animate({
           modes: ['linear',
                   'node-property:width:height',
                   'node-style:shadowColor',
                   'label-property:size'],
           hideLabels: false
         });
         (end code)
      */
      animate: function(opt, versor) {
        opt = $.merge(this.viz.config, opt || {});
        var that = this,
            viz = this.viz,
            graph  = viz.graph,
            interp = this.Interpolator,
            animation =  opt.type === 'nodefx'? this.nodeFxAnimation : this.animation;
        //prepare graph values
        var m = this.prepare(opt.modes);
        
        //animate
        if(opt.hideLabels) this.labels.hideLabels(true);
        animation.setOptions($.extend(opt, {
          $animating: false,
          compute: function(delta) {
            graph.eachNode(function(node) { 
              for(var p in m) {
                interp[p](node, m[p], delta, versor);
              }
            });
            that.plot(opt, this.$animating, delta);
            this.$animating = true;
          },
          complete: function() {
            if(opt.hideLabels) that.labels.hideLabels(false);
            that.plot(opt);
            opt.onComplete();
            //TODO(nico): This shouldn't be here!
            //opt.onAfterCompute();
          }       
        })).start();
      },
      
      /*
        nodeFx
     
        Apply animation to node properties like color, width, height, dim, etc.
    
        Parameters:
    
        options - Animation options. This object properties is described below
        elements - The Elements to be transformed. This is an object that has a properties
        
        (start code js)
        'elements': {
          //can also be an array of ids
          'id': 'id-of-node-to-transform',
          //properties to be modified. All properties are optional.
          'properties': {
            'color': '#ccc', //some color
            'width': 10, //some width
            'height': 10, //some height
            'dim': 20, //some dim
            'lineWidth': 10 //some line width
          } 
        }
        (end code)
        
        - _reposition_ Whether to recalculate positions and add a motion animation. 
        This might be used when changing _width_ or _height_ properties in a <Layouts.Tree> like layout. Default's *false*.
        
        - _onComplete_ A method that is called when the animation completes.
        
        ...and all other <Graph.Plot.animate> options like _duration_, _fps_, _transition_, etc.
    
        Example:
        (start code js)
         var rg = new RGraph(canvas, config); //can be also Hypertree or ST
         rg.fx.nodeFx({
           'elements': {
             'id':'mynodeid',
             'properties': {
               'color':'#ccf'
             },
             'transition': Trans.Quart.easeOut
           }
         });
        (end code)    
     */
     nodeFx: function(opt) {
       var viz = this.viz,
           graph  = viz.graph,
           animation = this.nodeFxAnimation,
           options = $.merge(this.viz.config, {
             'elements': {
               'id': false,
               'properties': {}
             },
             'reposition': false
           });
       opt = $.merge(options, opt || {}, {
         onBeforeCompute: $.empty,
         onAfterCompute: $.empty
       });
       //check if an animation is running
       animation.stopTimer();
       var props = opt.elements.properties;
       //set end values for nodes
       if(!opt.elements.id) {
         graph.eachNode(function(n) {
           for(var prop in props) {
             n.setData(prop, props[prop], 'end');
           }
         });
       } else {
         var ids = $.splat(opt.elements.id);
         $.each(ids, function(id) {
           var n = graph.getNode(id);
           if(n) {
             for(var prop in props) {
               n.setData(prop, props[prop], 'end');
             }
           }
         });
       }
       //get keys
       var propnames = [];
       for(var prop in props) propnames.push(prop);
       //add node properties modes
       var modes = ['node-property:' + propnames.join(':')];
       //set new node positions
       if(opt.reposition) {
         modes.push('linear');
         viz.compute('end');
       }
       //animate
       this.animate($.merge(opt, {
         modes: modes,
         type: 'nodefx'
       }));
     },
  
      
      /*
         Method: plot
      
         Plots a <Graph>.
  
         Parameters:
  
         opt - (optional) Plotting options. Most of them are described in <Options.Fx>.
  
         Example:
  
         (start code js)
         var viz = new $jit.Viz(options);
         viz.fx.plot(); 
         (end code)
  
      */
     plot: function(opt, animating) {
       var viz = this.viz, 
           aGraph = viz.graph, 
           canvas = viz.canvas, 
           id = viz.root, 
           that = this, 
           ctx = canvas.getCtx(), 
           min = Math.min,
           opt = opt || this.viz.controller;
       
       opt.clearCanvas && canvas.clear();
         
       var root = aGraph.getNode(id);
       if(!root) return;
       
       var T = !!root.visited;
       aGraph.eachNode(function(node) {
         var nodeAlpha = node.getData('alpha');
         node.eachAdjacency(function(adj) {
           var nodeTo = adj.nodeTo;
           if(!!nodeTo.visited === T && node.drawn && nodeTo.drawn) {
             !animating && opt.onBeforePlotLine(adj);
             that.plotLine(adj, canvas, animating);
             !animating && opt.onAfterPlotLine(adj);
           }
         });
         if(node.drawn) {
           !animating && opt.onBeforePlotNode(node);
           that.plotNode(node, canvas, animating);
           !animating && opt.onAfterPlotNode(node);
         }
         if(!that.labelsHidden && opt.withLabels) {
           if(node.drawn && nodeAlpha >= 0.95) {
             that.labels.plotLabel(canvas, node, opt);
           } else {
             that.labels.hideLabel(node, false);
           }
         }
         node.visited = !T;
       });
      },
  
    /*
        Plots a Subtree.
     */
     plotTree: function(node, opt, animating) {
         var that = this, 
             viz = this.viz, 
             canvas = viz.canvas,
             config = this.config,
             ctx = canvas.getCtx();
         var nodeAlpha = node.getData('alpha');
         node.eachSubnode(function(elem) {
           if(opt.plotSubtree(node, elem) && elem.exist && elem.drawn) {
               var adj = node.getAdjacency(elem.id);
               !animating && opt.onBeforePlotLine(adj);
               that.plotLine(adj, canvas, animating);
               !animating && opt.onAfterPlotLine(adj);
               that.plotTree(elem, opt, animating);
           }
         });
         if(node.drawn) {
             !animating && opt.onBeforePlotNode(node);
             this.plotNode(node, canvas, animating);
             !animating && opt.onAfterPlotNode(node);
             if(!opt.hideLabels && opt.withLabels && nodeAlpha >= 0.95) 
                 this.labels.plotLabel(canvas, node, opt);
             else 
                 this.labels.hideLabel(node, false);
         } else {
             this.labels.hideLabel(node, true);
         }
     },
  
    /*
         Method: plotNode
      
         Plots a <Graph.Node>.
  
         Parameters:
         
         node - (object) A <Graph.Node>.
         canvas - (object) A <Canvas> element.
  
      */
      plotNode: function(node, canvas, animating) {
          var f = node.getData('type'), 
              ctxObj = this.node.CanvasStyles;
          if(f != 'none') {
            var width = node.getData('lineWidth'),
                color = node.getData('color'),
                alpha = node.getData('alpha'),
                ctx = canvas.getCtx();
            ctx.save();
            ctx.lineWidth = width;
            ctx.fillStyle = ctx.strokeStyle = color;
            ctx.globalAlpha = alpha;
            
            for(var s in ctxObj) {
              ctx[s] = node.getCanvasStyle(s);
            }
  
            this.nodeTypes[f].render.call(this, node, canvas, animating);
            ctx.restore();
          }
      },
      
      /*
         Method: plotLine
      
         Plots a <Graph.Adjacence>.
  
         Parameters:
  
         adj - (object) A <Graph.Adjacence>.
         canvas - (object) A <Canvas> instance.
  
      */
      plotLine: function(adj, canvas, animating) {
        var f = adj.getData('type'),
            ctxObj = this.edge.CanvasStyles;
        if(f != 'none') {
          var width = adj.getData('lineWidth'),
              color = adj.getData('color'),
              ctx = canvas.getCtx(),
              nodeFrom = adj.nodeFrom,
              nodeTo = adj.nodeTo;
          
          ctx.save();
          ctx.lineWidth = width;
          ctx.fillStyle = ctx.strokeStyle = color;
          ctx.globalAlpha = Math.min(nodeFrom.getData('alpha'), 
              nodeTo.getData('alpha'), 
              adj.getData('alpha'));
          
          for(var s in ctxObj) {
            ctx[s] = adj.getCanvasStyle(s);
          }
  
          this.edgeTypes[f].render.call(this, adj, canvas, animating);
          ctx.restore();
        }
      }    
    
  };
  
  /*
   * File: Graph.Label.js
   *
  */
  
  /*
     Object: Graph.Label
  
     An interface for plotting/hiding/showing labels.
  
     Description:
  
     This is a generic interface for plotting/hiding/showing labels.
     The <Graph.Label> interface is implemented in multiple ways to provide
     different label types.
  
     For example, the Graph.Label interface is implemented as <Graph.Label.HTML> to provide
     HTML label elements. Also we provide the <Graph.Label.SVG> interface for SVG type labels. 
     The <Graph.Label.Native> interface implements these methods with the native Canvas text rendering functions.
     
     All subclasses (<Graph.Label.HTML>, <Graph.Label.SVG> and <Graph.Label.Native>) implement the method plotLabel.
  */
  
  Graph.Label = {};
  
  /*
     Class: Graph.Label.Native
  
     Implements labels natively, using the Canvas text API.
  */
  Graph.Label.Native = new Class({
      initialize: function(viz) {
        this.viz = viz;
      },
  
      /*
         Method: plotLabel
  
         Plots a label for a given node.
  
         Parameters:
  
         canvas - (object) A <Canvas> instance.
         node - (object) A <Graph.Node>.
         controller - (object) A configuration object.
         
         Example:
         
         (start code js)
         var viz = new $jit.Viz(options);
         var node = viz.graph.getNode('nodeId');
         viz.labels.plotLabel(viz.canvas, node, viz.config);
         (end code)
      */
      plotLabel: function(canvas, node, controller) {
        var ctx = canvas.getCtx();
        var pos = node.pos.getc(true);
  
        ctx.font = node.getLabelData('style') + ' ' + node.getLabelData('size') + 'px ' + node.getLabelData('family');
        ctx.textAlign = node.getLabelData('textAlign');
        ctx.fillStyle = ctx.strokeStyle = node.getLabelData('color');
        ctx.textBaseline = node.getLabelData('textBaseline');
  
        this.renderLabel(canvas, node, controller);
      },
  
      /*
         renderLabel
  
         Does the actual rendering of the label in the canvas. The default
         implementation renders the label close to the position of the node, this
         method should be overriden to position the labels differently.
  
         Parameters:
  
         canvas - A <Canvas> instance.
         node - A <Graph.Node>.
         controller - A configuration object. See also <Hypertree>, <RGraph>, <ST>.
      */
      renderLabel: function(canvas, node, controller) {
        var ctx = canvas.getCtx();
        var pos = node.pos.getc(true);
        ctx.fillText(node.name, pos.x, pos.y + node.getData("height") / 2);
      },
  
      /*
         Method: hideLabel
     
         Hides the corresponding <Graph.Node> label.
      
         Parameters:
     
         node - (object) A <Graph.Node>. Can also be an array of <Graph.Nodes>.
         show - (boolean) If *true*, nodes will be shown. Otherwise nodes will be hidden.
     
         Example:
         (start code js)
          var rg = new $jit.Viz(options);
          viz.labels.hideLabel(viz.graph.getNode('someid'), false);
         (end code)
      */
      hideLabel: function(node, show) {
        node = $.splat(node);
        var al = show ? false : true;
        $.each(node, function(n) {
          n._hideLabel = al;
        });
      },
      hideLabels: $.empty
  });
  
  /*
     Class: Graph.Label.DOM
  
     Abstract Class implementing some DOM label methods.
  
     Implemented by:
  
     <Graph.Label.HTML> and <Graph.Label.SVG>.
  
  */
  Graph.Label.DOM = new Class({
      //A flag value indicating if node labels are being displayed or not.
      labelsHidden: false,
      //Label container
      labelContainer: false,
      //Label elements hash.
      labels: {},
  
      /*
         Method: getLabelContainer
  
         Lazy fetcher for the label container.
  
         Returns:
  
         The label container DOM element.
  
         Example:
  
        (start code js)
          var viz = new $jit.Viz(options);
          var labelContainer = viz.labels.getLabelContainer();
          alert(labelContainer.innerHTML);
        (end code)
      */
      getLabelContainer: function() {
        return this.labelContainer ?
          this.labelContainer :
          this.labelContainer = document.getElementById(this.viz.config.labelContainer);
      },
  
      /*
         Method: getLabel
  
         Lazy fetcher for the label element.
  
         Parameters:
  
         id - (string) The label id (which is also a <Graph.Node> id).
  
         Returns:
  
         The label element.
  
         Example:
  
        (start code js)
          var viz = new $jit.Viz(options);
          var label = viz.labels.getLabel('someid');
          alert(label.innerHTML);
        (end code)
  
      */
      getLabel: function(id) {
        return (id in this.labels && this.labels[id] != null) ?
          this.labels[id] :
          this.labels[id] = document.getElementById(id);
      },
  
      /*
         Method: hideLabels
  
         Hides all labels (by hiding the label container).
  
         Parameters:
  
         hide - (boolean) A boolean value indicating if the label container must be hidden or not.
  
         Example:
         (start code js)
          var viz = new $jit.Viz(options);
          rg.labels.hideLabels(true);
         (end code)
  
      */
      hideLabels: function (hide) {
        var container = this.getLabelContainer();
        if(hide)
          container.style.display = 'none';
        else
          container.style.display = '';
        this.labelsHidden = hide;
      },
  
      /*
         Method: clearLabels
  
         Clears the label container.
  
         Useful when using a new visualization with the same canvas element/widget.
  
         Parameters:
  
         force - (boolean) Forces deletion of all labels.
  
         Example:
         (start code js)
          var viz = new $jit.Viz(options);
          viz.labels.clearLabels();
          (end code)
      */
      clearLabels: function(force) {
        for(var id in this.labels) {
          if (force || !this.viz.graph.hasNode(id)) {
            this.disposeLabel(id);
            delete this.labels[id];
          }
        }
      },
  
      /*
         Method: disposeLabel
  
         Removes a label.
  
         Parameters:
  
         id - (string) A label id (which generally is also a <Graph.Node> id).
  
         Example:
         (start code js)
          var viz = new $jit.Viz(options);
          viz.labels.disposeLabel('labelid');
         (end code)
      */
      disposeLabel: function(id) {
        var elem = this.getLabel(id);
        if(elem && elem.parentNode) {
          elem.parentNode.removeChild(elem);
        }
      },
  
      /*
         Method: hideLabel
  
         Hides the corresponding <Graph.Node> label.
  
         Parameters:
  
         node - (object) A <Graph.Node>. Can also be an array of <Graph.Nodes>.
         show - (boolean) If *true*, nodes will be shown. Otherwise nodes will be hidden.
  
         Example:
         (start code js)
          var rg = new $jit.Viz(options);
          viz.labels.hideLabel(viz.graph.getNode('someid'), false);
         (end code)
      */
      hideLabel: function(node, show) {
        node = $.splat(node);
        var st = show ? "" : "none", lab, that = this;
        $.each(node, function(n) {
          lab = that.getLabel(n.id);
          if (lab) {
            lab.style.display = st;
          }
        });
      },
  
      /*
         fitsInCanvas
  
         Returns _true_ or _false_ if the label for the node is contained in the canvas dom element or not.
  
         Parameters:
  
         pos - A <Complex> instance (I'm doing duck typing here so any object with _x_ and _y_ parameters will do).
         canvas - A <Canvas> instance.
  
         Returns:
  
         A boolean value specifying if the label is contained in the <Canvas> DOM element or not.
  
      */
      fitsInCanvas: function(pos, canvas) {
        var size = canvas.getSize();
        if (pos.w && pos.h) {
        	if (pos.x >= size.width || pos.x < -pos.w
           || pos.y >= size.height || pos.y < -pos.h) return false;      	
        }
        else {
        	if (pos.x >= size.width || pos.x < 0
           || pos.y >= size.height || pos.y < 0) return false;
        }
         return true;
      }
  });
  
  /*
     Class: Graph.Label.HTML
  
     Implements HTML labels.
  
     Extends:
  
     All <Graph.Label.DOM> methods.
  
  */
  Graph.Label.HTML = new Class({
      Implements: Graph.Label.DOM,
  
      /*
         Method: plotLabel
  
         Plots a label for a given node.
  
         Parameters:
  
         canvas - (object) A <Canvas> instance.
         node - (object) A <Graph.Node>.
         controller - (object) A configuration object.
         
        Example:
         
         (start code js)
         var viz = new $jit.Viz(options);
         var node = viz.graph.getNode('nodeId');
         viz.labels.plotLabel(viz.canvas, node, viz.config);
         (end code)
  
  
      */
      plotLabel: function(canvas, node, controller) {
        var id = node.id, tag = this.getLabel(id);
  
        if(!tag && !(tag = document.getElementById(id))) {
          tag = document.createElement('div');
          var container = this.getLabelContainer();
          tag.id = id;
          tag.className = 'node';
          tag.style.position = 'absolute';
          controller.onCreateLabel(tag, node);
          container.appendChild(tag);
          this.labels[node.id] = tag;
        }
  
        this.placeLabel(tag, node, controller);
      }
  });
  
  /*
     Class: Graph.Label.SVG
  
     Implements SVG labels.
  
     Extends:
  
     All <Graph.Label.DOM> methods.
  */
  Graph.Label.SVG = new Class({
      Implements: Graph.Label.DOM,
  
      /*
         Method: plotLabel
  
         Plots a label for a given node.
  
         Parameters:
  
         canvas - (object) A <Canvas> instance.
         node - (object) A <Graph.Node>.
         controller - (object) A configuration object.
         
         Example:
         
         (start code js)
         var viz = new $jit.Viz(options);
         var node = viz.graph.getNode('nodeId');
         viz.labels.plotLabel(viz.canvas, node, viz.config);
         (end code)
  
  
      */
      plotLabel: function(canvas, node, controller) {
        var id = node.id, tag = this.getLabel(id);
        if(!tag && !(tag = document.getElementById(id))) {
          var ns = 'https://www.w3.org/2000/svg';
            tag = document.createElementNS(ns, 'svg:text');
          var tspan = document.createElementNS(ns, 'svg:tspan');
          tag.appendChild(tspan);
          var container = this.getLabelContainer();
          tag.setAttribute('id', id);
          tag.setAttribute('class', 'node');
          container.appendChild(tag);
          controller.onCreateLabel(tag, node);
          this.labels[node.id] = tag;
        }
        this.placeLabel(tag, node, controller);
      }
  });
  
  
  
  Graph.Geom = new Class({
  
    initialize: function(viz) {
      this.viz = viz;
      this.config = viz.config;
      this.node = viz.config.Node;
      this.edge = viz.config.Edge;
    },
    /*
      Applies a translation to the tree.
    
      Parameters:
    
      pos - A <Complex> number specifying translation vector.
      prop - A <Graph.Node> position property ('pos', 'start' or 'end').
    
      Example:
    
      (start code js)
        st.geom.translate(new Complex(300, 100), 'end');
      (end code)
    */  
    translate: function(pos, prop) {
       prop = $.splat(prop);
       this.viz.graph.eachNode(function(elem) {
           $.each(prop, function(p) { elem.getPos(p).$add(pos); });
       });
    },
    /*
      Hides levels of the tree until it properly fits in canvas.
    */  
    setRightLevelToShow: function(node, canvas, callback) {
       var level = this.getRightLevelToShow(node, canvas), 
           fx = this.viz.labels,
           opt = $.merge({
             execShow:true,
             execHide:true,
             onHide: $.empty,
             onShow: $.empty
           }, callback || {});
       node.eachLevel(0, this.config.levelsToShow, function(n) {
           var d = n._depth - node._depth;
           if(d > level) {
               opt.onHide(n);
               if(opt.execHide) {
                 n.drawn = false; 
                 n.exist = false;
                 fx.hideLabel(n, false);
               }
           } else {
               opt.onShow(n);
               if(opt.execShow) {
                 n.exist = true;
               }
           }
       });
       node.drawn= true;
    },
    /*
      Returns the right level to show for the current tree in order to fit in canvas.
    */  
    getRightLevelToShow: function(node, canvas) {
       var config = this.config;
       var level = config.levelsToShow;
       var constrained = config.constrained;
       if(!constrained) return level;
       while(!this.treeFitsInCanvas(node, canvas, level) && level > 1) { level-- ; }
       return level;
    }
  });
  
  /*
   * File: Loader.js
   * 
   */
  
  /*
     Object: Loader
  
     Provides methods for loading and serving JSON data.
  */
  var Loader = {
       construct: function(json) {
          var isGraph = ($.type(json) == 'array');
          var ans = new Graph(this.graphOptions, this.config.Node, this.config.Edge, this.config.Label);
          if(!isGraph) 
              //make tree
              (function (ans, json) {
                  ans.addNode(json);
                  if(json.children) {
                    for(var i=0, ch = json.children; i<ch.length; i++) {
                      ans.addAdjacence(json, ch[i]);
                      arguments.callee(ans, ch[i]);
                    }
                  }
              })(ans, json);
          else
              //make graph
              (function (ans, json) {
                  var getNode = function(id) {
                    for(var i=0, l=json.length; i<l; i++) {
                      if(json[i].id == id) {
                        return json[i];
                      }
                    }
                    // The node was not defined in the JSON
                    // Let's create it
                    var newNode = {
                  		"id" : id,
                  		"name" : id
                  	};
                    return ans.addNode(newNode);
                  };
  
                  for(var i=0, l=json.length; i<l; i++) {
                    ans.addNode(json[i]);
                    var adj = json[i].adjacencies;
                    if (adj) {
                      for(var j=0, lj=adj.length; j<lj; j++) {
                        var node = adj[j], data = {};
                        if(typeof adj[j] != 'string') {
                          data = $.merge(node.data, {});
                          node = node.nodeTo;
                        }
                        ans.addAdjacence(json[i], getNode(node), data);
                      }
                    }
                  }
              })(ans, json);
  
          return ans;
      },
  
      /*
       Method: loadJSON
      
       Loads a JSON structure to the visualization. The JSON structure can be a JSON *tree* or *graph* structure.
       
        A JSON tree or graph structure consists of nodes, each having as properties
         
         id - (string) A unique identifier for the node
         name - (string) A node's name
         data - (object) The data optional property contains a hash (i.e {}) 
         where you can store all the information you want about this node.
          
        For JSON *Tree* structures, there's an extra optional property *children* of type Array which contains the node's children.
        
        Example:
  
        (start code js)
          var json = {  
            "id": "aUniqueIdentifier",  
            "name": "usually a nodes name",  
            "data": {
              "some key": "some value",
              "some other key": "some other value"
             },  
            "children": [ *other nodes or empty* ]  
          };  
        (end code)
          
          JSON *Graph* structures consist of an array of nodes, each specifying the nodes to which the current node is connected. 
          For JSON *Graph* structures, the *children* property is replaced by the *adjacencies* property.
          
          There are two types of *Graph* structures, *simple* and *extended* graph structures.
          
          For *simple* Graph structures, the adjacencies property contains an array of strings, each specifying the 
          id of the node connected to the main node.
          
          Example:
          
          (start code js)
          var json = [  
            {  
              "id": "aUniqueIdentifier",  
              "name": "usually a nodes name",  
              "data": {
                "some key": "some value",
                "some other key": "some other value"
               },  
              "adjacencies": ["anotherUniqueIdentifier", "yetAnotherUniqueIdentifier", 'etc']  
            },
  
            'other nodes go here...' 
          ];          
          (end code)
          
          For *extended Graph structures*, the adjacencies property contains an array of Adjacency objects that have as properties
          
          nodeTo - (string) The other node connected by this adjacency.
          data - (object) A data property, where we can store custom key/value information.
          
          Example:
          
          (start code js)
          var json = [  
            {  
              "id": "aUniqueIdentifier",  
              "name": "usually a nodes name",  
              "data": {
                "some key": "some value",
                "some other key": "some other value"
               },  
              "adjacencies": [  
              {  
                nodeTo:"aNodeId",  
                data: {} //put whatever you want here  
              },
              'other adjacencies go here...'  
            },
  
            'other nodes go here...' 
          ];          
          (end code)
         
         About the data property:
         
         As described before, you can store custom data in the *data* property of JSON *nodes* and *adjacencies*. 
         You can use almost any string as key for the data object. Some keys though are reserved by the toolkit, and 
         have special meanings. This is the case for keys starting with a dollar sign, for example, *$width*.
         
         For JSON *node* objects, adding dollar prefixed properties that match the names of the options defined in 
         <Options.Node> will override the general value for that option with that particular value. For this to work 
         however, you do have to set *overridable = true* in <Options.Node>.
         
         The same thing is true for JSON adjacencies. Dollar prefixed data properties will alter values set in <Options.Edge> 
         if <Options.Edge> has *overridable = true*.
         
         When loading JSON data into TreeMaps, the *data* property must contain a value for the *$area* key, 
         since this is the value which will be taken into account when creating the layout. 
         The same thing goes for the *$color* parameter.
         
         In JSON Nodes you can use also *$label-* prefixed properties to refer to <Options.Label> properties. For example, 
         *$label-size* will refer to <Options.Label> size property. Also, in JSON nodes and adjacencies you can set 
         canvas specific properties individually by using the *$canvas-* prefix. For example, *$canvas-shadowBlur* will refer 
         to the *shadowBlur* property.
         
         These properties can also be accessed after loading the JSON data from <Graph.Nodes> and <Graph.Adjacences> 
         by using <Accessors>. For more information take a look at the <Graph> and <Accessors> documentation.
         
         Finally, these properties can also be used to create advanced animations like with <Options.NodeStyles>. For more 
         information about creating animations please take a look at the <Graph.Plot> and <Graph.Plot.animate> documentation.
         
         loadJSON Parameters:
      
          json - A JSON Tree or Graph structure.
          i - For Graph structures only. Sets the indexed node as root for the visualization.
  
      */
      loadJSON: function(json, i) {
        this.json = json;
        //if they're canvas labels erase them.
        if(this.labels && this.labels.clearLabels) {
          this.labels.clearLabels(true);
        }
        this.graph = this.construct(json);
        if($.type(json) != 'array'){
          this.root = json.id;
        } else {
          this.root = json[i? i : 0].id;
        }
      },
      
      /*
        Method: toJSON
     
        Returns a JSON tree/graph structure from the visualization's <Graph>. 
        See <Loader.loadJSON> for the graph formats available.
        
        See also:
        
        <Loader.loadJSON>
        
        Parameters:
        
        type - (string) Default's "tree". The type of the JSON structure to be returned. 
        Possible options are "tree" or "graph".
      */    
      toJSON: function(type) {
        type = type || "tree";
        if(type == 'tree') {
          var ans = {};
          var rootNode = this.graph.getNode(this.root);
          var ans = (function recTree(node) {
            var ans = {};
            ans.id = node.id;
            ans.name = node.name;
            ans.data = node.data;
            var ch =[];
            node.eachSubnode(function(n) {
              ch.push(recTree(n));
            });
            ans.children = ch;
            return ans;
          })(rootNode);
          return ans;
        } else {
          var ans = [];
          var T = !!this.graph.getNode(this.root).visited;
          this.graph.eachNode(function(node) {
            var ansNode = {};
            ansNode.id = node.id;
            ansNode.name = node.name;
            ansNode.data = node.data;
            var adjs = [];
            node.eachAdjacency(function(adj) {
              var nodeTo = adj.nodeTo;
              if(!!nodeTo.visited === T) {
                var ansAdj = {};
                ansAdj.nodeTo = nodeTo.id;
                ansAdj.data = adj.data;
                adjs.push(ansAdj);
              }
            });
            ansNode.adjacencies = adjs;
            ans.push(ansNode);
            node.visited = !T;
          });
          return ans;
        }
      }
  };
  
  
  
  /*
   * File: Layouts.js
   * 
   * Implements base Tree and Graph layouts.
   *
   * Description:
   *
   * Implements base Tree and Graph layouts like Radial, Tree, etc.
   * 
   */
  
  /*
   * Object: Layouts
   * 
   * Parent object for common layouts.
   *
   */
  var Layouts = $jit.Layouts = {};
  
  
  //Some util shared layout functions are defined here.
  var NodeDim = {
    label: null,
    
    compute: function(graph, prop, opt) {
      this.initializeLabel(opt);
      var label = this.label, style = label.style;
      graph.eachNode(function(n) {
        var autoWidth  = n.getData('autoWidth'),
            autoHeight = n.getData('autoHeight');
        if(autoWidth || autoHeight) {
          //delete dimensions since these are
          //going to be overridden now.
          delete n.data.$width;
          delete n.data.$height;
          delete n.data.$dim;
          
          var width  = n.getData('width'),
              height = n.getData('height');
          //reset label dimensions
          style.width  = autoWidth? 'auto' : width + 'px';
          style.height = autoHeight? 'auto' : height + 'px';
          
          //TODO(nico) should let the user choose what to insert here.
          label.innerHTML = n.name;
          
          var offsetWidth  = label.offsetWidth,
              offsetHeight = label.offsetHeight;
          var type = n.getData('type');
          if($.indexOf(['circle', 'square', 'triangle', 'star'], type) === -1) {
            n.setData('width', offsetWidth);
            n.setData('height', offsetHeight);
          } else {
            var dim = offsetWidth > offsetHeight? offsetWidth : offsetHeight;
            n.setData('width', dim);
            n.setData('height', dim);
            n.setData('dim', dim); 
          }
        }
      });
    },
    
    initializeLabel: function(opt) {
      if(!this.label) {
        this.label = document.createElement('div');
        document.body.appendChild(this.label);
      }
      this.setLabelStyles(opt);
    },
    
    setLabelStyles: function(opt) {
      $.extend(this.label.style, {
        'visibility': 'hidden',
        'position': 'absolute',
        'width': 'auto',
        'height': 'auto'
      });
      this.label.className = 'jit-autoadjust-label';
    }
  };
  
  
  /*
   * Class: Layouts.TM
   * 
   * Implements TreeMaps layouts (SliceAndDice, Squarified, Strip).
   * 
   * Implemented By:
   * 
   * <TM>
   * 
   */
  Layouts.TM = {};
  
  Layouts.TM.SliceAndDice = new Class({
    compute: function(prop) {
      var root = this.graph.getNode(this.clickedNode && this.clickedNode.id || this.root);
      this.controller.onBeforeCompute(root);
      var size = this.canvas.getSize(),
          config = this.config,
          width = size.width,
          height = size.height;
      this.graph.computeLevels(this.root, 0, "ignore");
      //set root position and dimensions
      root.getPos(prop).setc(-width/2, -height/2);
      root.setData('width', width, prop);
      root.setData('height', height + config.titleHeight, prop);
      this.computePositions(root, root, this.layout.orientation, prop);
      this.controller.onAfterCompute(root);
    },
    
    computePositions: function(par, ch, orn, prop) {
      //compute children areas
      var totalArea = 0;
      par.eachSubnode(function(n) {
        totalArea += n.getData('area', prop);
      });
      
      var config = this.config,
          offset = config.offset,
          width  = par.getData('width', prop),
          height = Math.max(par.getData('height', prop) - config.titleHeight, 0),
          fact = par == ch? 1 : (ch.getData('area', prop) / totalArea);
  
      var otherSize, size, dim, pos, pos2, posth, pos2th;
      var horizontal = (orn == "h");
      if(horizontal) {
        orn = 'v';
        otherSize = height;
        size = width * fact;
        dim = 'height';
        pos = 'y';
        pos2 = 'x';
        posth = config.titleHeight;
        pos2th = 0;
      } else {
        orn = 'h';    
        otherSize = height * fact;
        size = width;
        dim = 'width';
        pos = 'x';
        pos2 = 'y';
        posth = 0;
        pos2th = config.titleHeight;
      }
      var cpos = ch.getPos(prop);
      ch.setData('width', size, prop);
      ch.setData('height', otherSize, prop);
      var offsetSize = 0, tm = this;
      ch.eachSubnode(function(n) {
        var p = n.getPos(prop);
        p[pos] = offsetSize + cpos[pos] + posth;
        p[pos2] = cpos[pos2] + pos2th;
        tm.computePositions(ch, n, orn, prop);
        offsetSize += n.getData(dim, prop);
      });
    }
  
  });
  
  Layouts.TM.Area = {
   /*
      Method: compute
   
     Called by loadJSON to calculate recursively all node positions and lay out the tree.
   
      Parameters:
  
         json - A JSON tree. See also <Loader.loadJSON>.
         coord - A coordinates object specifying width, height, left and top style properties.
   */
   compute: function(prop) {
      prop = prop || "current";
      var root = this.graph.getNode(this.clickedNode && this.clickedNode.id || this.root);
      this.controller.onBeforeCompute(root);
      var config = this.config,
          size = this.canvas.getSize(),
          width = size.width,
          height = size.height,
          offst = config.offset,
          offwdth = width - offst,
          offhght = height - offst;
      this.graph.computeLevels(this.root, 0, "ignore");
      //set root position and dimensions
      root.getPos(prop).setc(-width/2, -height/2);
      root.setData('width', width, prop);
      root.setData('height', height, prop);
      //create a coordinates object
      var coord = {
          'top': -height/2 + config.titleHeight + offst / 2,
          'left': -width/2 + offst / 2,
          'width': offwdth,
          'height': offhght - config.titleHeight
      };
      this.computePositions(root, coord, prop);
      this.controller.onAfterCompute(root);
   }, 
   
   /*
      Method: computeDim
   
     Computes dimensions and positions of a group of nodes
     according to a custom layout row condition. 
   
      Parameters:
  
         tail - An array of nodes.  
         initElem - An array of nodes (containing the initial node to be laid).
         w - A fixed dimension where nodes will be layed out.
         coord - A coordinates object specifying width, height, left and top style properties.
         comp - A custom comparison function
   */
   computeDim: function(tail, initElem, w, coord, comp, prop) {
     if(tail.length + initElem.length == 1) {
       var l = (tail.length == 1)? tail : initElem;
       this.layoutLast(l, w, coord, prop);
       return;
     }
     if(tail.length >= 2 && initElem.length == 0) {
       initElem = [tail.shift()];
     }
     if(tail.length == 0) {
       if(initElem.length > 0) this.layoutRow(initElem, w, coord, prop);
       return;
     }
     var c = tail[0];
     if(comp(initElem, w) >= comp([c].concat(initElem), w)) {
       this.computeDim(tail.slice(1), initElem.concat([c]), w, coord, comp, prop);
     } else {
       var newCoords = this.layoutRow(initElem, w, coord, prop);
       this.computeDim(tail, [], newCoords.dim, newCoords, comp, prop);
     }
   },
  
   
   /*
      Method: worstAspectRatio
   
     Calculates the worst aspect ratio of a group of rectangles. 
         
      See also:
         
         <http://en.wikipedia.org/wiki/Aspect_ratio>
     
      Parameters:
  
       ch - An array of nodes.  
       w  - The fixed dimension where rectangles are being laid out.
  
      Returns:
   
          The worst aspect ratio.
  
  
   */
   worstAspectRatio: function(ch, w) {
     if(!ch || ch.length == 0) return Number.MAX_VALUE;
     var areaSum = 0, maxArea = 0, minArea = Number.MAX_VALUE;
     for(var i=0, l=ch.length; i<l; i++) {
       var area = ch[i]._area;
       areaSum += area; 
       minArea = minArea < area? minArea : area;
       maxArea = maxArea > area? maxArea : area; 
     }
     var sqw = w * w, sqAreaSum = areaSum * areaSum;
     return Math.max(sqw * maxArea / sqAreaSum,
             sqAreaSum / (sqw * minArea));
   },
   
   /*
      Method: avgAspectRatio
   
     Calculates the average aspect ratio of a group of rectangles. 
         
         See also:
         
         <http://en.wikipedia.org/wiki/Aspect_ratio>
     
      Parameters:
  
       ch - An array of nodes.  
         w - The fixed dimension where rectangles are being laid out.
  
      Returns:
   
          The average aspect ratio.
  
  
   */
   avgAspectRatio: function(ch, w) {
     if(!ch || ch.length == 0) return Number.MAX_VALUE;
     var arSum = 0;
     for(var i=0, l=ch.length; i<l; i++) {
       var area = ch[i]._area;
       var h = area / w;
       arSum += w > h? w / h : h / w;
     }
     return arSum / l;
   },
  
   /*
      layoutLast
   
     Performs the layout of the last computed sibling.
   
      Parameters:
  
         ch - An array of nodes.  
         w - A fixed dimension where nodes will be layed out.
       coord - A coordinates object specifying width, height, left and top style properties.
   */
   layoutLast: function(ch, w, coord, prop) {
     var child = ch[0];
     child.getPos(prop).setc(coord.left, coord.top);
     child.setData('width', coord.width, prop);
     child.setData('height', coord.height, prop);
   }
  };
  
  
  Layouts.TM.Squarified = new Class({
   Implements: Layouts.TM.Area,
   
   computePositions: function(node, coord, prop) {
     var config = this.config, 
         max = Math.max;
     
     if (coord.width >= coord.height) 
       this.layout.orientation = 'h';
     else
       this.layout.orientation = 'v';
     
     var ch = node.getSubnodes([1, 1], "ignore");
     if(ch.length > 0) {
       this.processChildrenLayout(node, ch, coord, prop);
       for(var i=0, l=ch.length; i<l; i++) {
         var chi = ch[i], 
             offst = config.offset,
             height = max(chi.getData('height', prop) - offst - config.titleHeight, 0),
             width = max(chi.getData('width', prop) - offst, 0),
             chipos = chi.getPos(prop);
  
         coord = {
           'width': width,
           'height': height,
           'top': chipos.y + config.titleHeight + offst / 2,
           'left': chipos.x + offst / 2
         };
         this.computePositions(chi, coord, prop);
       }
     }
   },
  
   /*
      Method: processChildrenLayout
   
     Computes children real areas and other useful parameters for performing the Squarified algorithm.
   
      Parameters:
  
         par - The parent node of the json subtree.  
         ch - An Array of nodes
       coord - A coordinates object specifying width, height, left and top style properties.
   */
   processChildrenLayout: function(par, ch, coord, prop) {
     //compute children real areas
     var parentArea = coord.width * coord.height;
     var i, l=ch.length, totalChArea=0, chArea = [];
     for(i=0; i<l; i++) {
       chArea[i] = parseFloat(ch[i].getData('area', prop));
       totalChArea += chArea[i];
     }
     for(i=0; i<l; i++) {
       ch[i]._area = parentArea * chArea[i] / totalChArea;
     }
     var minimumSideValue = this.layout.horizontal()? coord.height : coord.width;
     ch.sort(function(a, b) { 
       var diff = b._area - a._area; 
       return diff? diff : (b.id == a.id? 0 : (b.id < a.id? 1 : -1)); 
     });
     var initElem = [ch[0]];
     var tail = ch.slice(1);
     this.squarify(tail, initElem, minimumSideValue, coord, prop);
   },
  
   /*
     Method: squarify
   
     Performs an heuristic method to calculate div elements sizes in order to have a good aspect ratio.
   
      Parameters:
  
         tail - An array of nodes.  
         initElem - An array of nodes, containing the initial node to be laid out.
         w - A fixed dimension where nodes will be laid out.
         coord - A coordinates object specifying width, height, left and top style properties.
   */
   squarify: function(tail, initElem, w, coord, prop) {
     this.computeDim(tail, initElem, w, coord, this.worstAspectRatio, prop);
   },
   
   /*
      Method: layoutRow
   
     Performs the layout of an array of nodes.
   
      Parameters:
  
         ch - An array of nodes.  
         w - A fixed dimension where nodes will be laid out.
         coord - A coordinates object specifying width, height, left and top style properties.
   */
   layoutRow: function(ch, w, coord, prop) {
     if(this.layout.horizontal()) {
       return this.layoutV(ch, w, coord, prop);
     } else {
       return this.layoutH(ch, w, coord, prop);
     }
   },
   
  layoutV: function(ch, w, coord, prop) {
     var totalArea = 0, rnd = function(x) { return x; };
     $.each(ch, function(elem) { totalArea += elem._area; });
     var width = rnd(totalArea / w) || 0, top =  0;
     for(var i=0, l=ch.length; i<l; i++) {
       var h = rnd(ch[i]._area / width) || 0;
       var chi = ch[i];
       chi.getPos(prop).setc(coord.left, coord.top + top);
       chi.setData('width', width, prop);
       chi.setData('height', h, prop);
       top += h;
     }
     var ans = {
       'height': coord.height,
       'width': coord.width - width,
       'top': coord.top,
       'left': coord.left + width
     };
     //take minimum side value.
     ans.dim = Math.min(ans.width, ans.height);
     if(ans.dim != ans.height) this.layout.change();
     return ans;
   },
  
   layoutH: function(ch, w, coord, prop) {
     var totalArea = 0;
     $.each(ch, function(elem) { totalArea += elem._area; });
     var height = totalArea / w || 0,
         top = coord.top,
         left = 0;
  
     for(var i=0, l=ch.length; i<l; i++) {
       var chi = ch[i];
       var w = chi._area / height || 0;
       chi.getPos(prop).setc(coord.left + left, top);
       chi.setData('width', w, prop);
       chi.setData('height', height, prop);
       left += w;
     }
     var ans = {
       'height': coord.height - height,
       'width': coord.width,
       'top': coord.top + height,
       'left': coord.left
     };
     ans.dim = Math.min(ans.width, ans.height);
     if(ans.dim != ans.width) this.layout.change();
     return ans;
   }
  });
  
  Layouts.TM.Strip = new Class({
    Implements: Layouts.TM.Area,
  
      /*
        Method: compute
      
       Called by loadJSON to calculate recursively all node positions and lay out the tree.
      
        Parameters:
      
           json - A JSON subtree. See also <Loader.loadJSON>. 
         coord - A coordinates object specifying width, height, left and top style properties.
      */
      computePositions: function(node, coord, prop) {
       var  ch = node.getSubnodes([1, 1], "ignore"), 
            config = this.config,
            max = Math.max;
       if(ch.length > 0) {
         this.processChildrenLayout(node, ch, coord, prop);
         for(var i=0, l=ch.length; i<l; i++) {
           var chi = ch[i];
           var offst = config.offset,
               height = max(chi.getData('height', prop) - offst - config.titleHeight, 0),
               width  = max(chi.getData('width', prop)  - offst, 0);
           var chipos = chi.getPos(prop);
           coord = {
             'width': width,
             'height': height,
             'top': chipos.y + config.titleHeight + offst / 2,
             'left': chipos.x + offst / 2
           };
           this.computePositions(chi, coord, prop);
         }
       }
      },
      
      /*
        Method: processChildrenLayout
      
       Computes children real areas and other useful parameters for performing the Strip algorithm.
      
        Parameters:
      
           par - The parent node of the json subtree.  
           ch - An Array of nodes
           coord - A coordinates object specifying width, height, left and top style properties.
      */
      processChildrenLayout: function(par, ch, coord, prop) {
       //compute children real areas
        var parentArea = coord.width * coord.height;
        var i, l=ch.length, totalChArea=0, chArea = [];
        for(i=0; i<l; i++) {
          chArea[i] = +ch[i].getData('area', prop);
          totalChArea += chArea[i];
        }
        for(i=0; i<l; i++) {
          ch[i]._area = parentArea * chArea[i] / totalChArea;
        }
       var side = this.layout.horizontal()? coord.width : coord.height;
       var initElem = [ch[0]];
       var tail = ch.slice(1);
       this.stripify(tail, initElem, side, coord, prop);
      },
      
      /*
        Method: stripify
      
       Performs an heuristic method to calculate div elements sizes in order to have 
       a good compromise between aspect ratio and order.
      
        Parameters:
      
           tail - An array of nodes.  
           initElem - An array of nodes.
           w - A fixed dimension where nodes will be layed out.
         coord - A coordinates object specifying width, height, left and top style properties.
      */
      stripify: function(tail, initElem, w, coord, prop) {
       this.computeDim(tail, initElem, w, coord, this.avgAspectRatio, prop);
      },
      
      /*
        Method: layoutRow
      
       Performs the layout of an array of nodes.
      
        Parameters:
      
           ch - An array of nodes.  
           w - A fixed dimension where nodes will be laid out.
           coord - A coordinates object specifying width, height, left and top style properties.
      */
      layoutRow: function(ch, w, coord, prop) {
       if(this.layout.horizontal()) {
         return this.layoutH(ch, w, coord, prop);
       } else {
         return this.layoutV(ch, w, coord, prop);
       }
      },
      
      layoutV: function(ch, w, coord, prop) {
       var totalArea = 0; 
       $.each(ch, function(elem) { totalArea += elem._area; });
       var width = totalArea / w, top =  0; 
       for(var i=0, l=ch.length; i<l; i++) {
         var chi = ch[i];
         var h = chi._area / width;
         chi.getPos(prop).setc(coord.left, 
             coord.top + (w - h - top));
         chi.setData('width', width, prop);
         chi.setData('height', h, prop);
         top += h;
       }
      
       return {
         'height': coord.height,
         'width': coord.width - width,
         'top': coord.top,
         'left': coord.left + width,
         'dim': w
       };
      },
      
      layoutH: function(ch, w, coord, prop) {
       var totalArea = 0; 
       $.each(ch, function(elem) { totalArea += elem._area; });
       var height = totalArea / w,
           top = coord.height - height, 
           left = 0;
       
       for(var i=0, l=ch.length; i<l; i++) {
         var chi = ch[i];
         var s = chi._area / height;
         chi.getPos(prop).setc(coord.left + left, coord.top + top);
         chi.setData('width', s, prop);
         chi.setData('height', height, prop);
         left += s;
       }
       return {
         'height': coord.height - height,
         'width': coord.width,
         'top': coord.top,
         'left': coord.left,
         'dim': w
       };
      }
   });
  
  
  Layouts.TM.Voronoi = new Class({
    Implements : Layouts.TM.Area,
    compute : function(prop) {
      this.controller.onBeforeCompute(root);
      var root = this.graph.getNode(this.clickedNode && this.clickedNode.id || this.root),
          size = this.canvas.getSize(),
          config = this.config,
          offset = config.offset,
          width = size.width,
          height = size.height;
  
      this.graph.computeLevels(this.root, 0, 0);
  
      // set root position and dimensions
      root.getPos(prop).setc(-5, -5);
      if (!root.histoPos) {
        root.histoPos = [];
      }
      root.histoPos[0] = $C(0, 0);
      var bound = [
        $C(-width * 0.5, -height * 0.5),
        $C(width * 0.5, -height * 0.5),
        $C(width * 0.5, height * 0.5),
        $C(-width * 0.5, height * 0.5)
      ];
      bound = Geometry.offsetConvex(bound, -offset * 0.5);
      root.setData('vertices', bound, prop);
      root.setData('width', 0, prop);
      root.setData('height', 0, prop);
  
      bound = Geometry.offsetConvex(bound, -offset * 1.5);
      this.computePositions(root, bound, prop, 0);
      this.controller.onAfterCompute(root);
    },
  
  
    computePositions : function(node, bound, prop, level) {
      var me = this,
          chs = node.getSubnodes([ 1, 1 ], "ignore"),
          config = this.config,
          offset = config.offset,
          historyPosition = node.histoPos[level] || c(0, 0),
          sites,
          polygons;
  
      node.setData('width', 0, prop);
      node.setData('height', 0, prop);
      node.getPos(prop).setc(historyPosition.x, historyPosition.y);
  
      if (chs.length > 0) {
        if (!chs[0].histoPos || !chs[0].histoPos[level + 1]) {
          sites = $jit.util.map(chs, function(ch) {
            var pt = Geometry.randPointInPolygon(bound);
            if (ch.data && ch.data.$area)
              pt.area = ch.data.$area;
            return pt;
          });
          sites = me[me.config.centroidType](sites, bound);
          $jit.util.each(sites, function(p, i) {
            if (!chs[i].histoPos) {
              chs[i].histoPos = [];
            }
            chs[i].histoPos[level + 1] = p;
          });
        }
        sites = $jit.util.map(chs, function(ch) {
          return ch.histoPos[level + 1];
        });
        polygons = Geometry.voronoi(sites, bound);
  
        $jit.util.each(chs, function(ch, i) {
          var vertices = polygons[i];
          var newBoundary = vertices.slice(0);
          if (Geometry.area(vertices) < 0) {
            vertices.reverse();
          }
          if (offset) {
            newBoundary = Geometry.offsetConvex(vertices, -offset * 2);
            vertices = Geometry.offsetConvex(vertices, -offset * 0.5);
            ch.offset = offset;
          }
          ch.setData('vertices', vertices, prop);
          me.computePositions(ch, newBoundary, prop, level + 1);
        });
      }
    },
  
    centroid : function(sites, bound) {
      var tdist = 2, polygons;
      while (tdist > 1e-3) {
        polygons = Geometry.voronoi(sites, bound);
        tdist = 0;
        sites = polygons.map(function(p, j) {
          var c = Geometry.centroid(p);
          tdist += Geometry.dist2(c, sites[j]);
          return c;
        });
      }
      return sites;
    },
  
    doLayoutPressure: function () {
      var me = this,
          root = me.graph.getNode(me.clickedNode && me.clickedNode.id || me.root);
      root.eachNode(function() {
  
      });
    },
    
    weightedCentroid : function(sites, bound) {
      // sites = this.centroid(sites, bound);
      var pascal = [];
      var tdist = 2, polygons, totalArea = Geometry.area(bound), totalWeight = 0, adjust;
      $.each(sites, function(site, i) {
        totalWeight += site.area;
      });
      adjust = totalArea / totalWeight;
      polygons = Geometry.voronoi(sites, bound);
      $.each(polygons, function(p, i) {
          pascal[i] = sites[i].area * adjust / Geometry.area(p);
        });
      var s = 0, s2 = 0;
      $.each(pascal, function(p, i) {
        s += p;
        s2 += p * p;
      });
  //    console.log('from ' + (s2 - s * s / pascal.length) / pascal.length);
      while (tdist > 1e-3) {
        polygons = Geometry.voronoi(sites, bound);
        $.each(polygons, function(p, i) {
          pascal[i] = sites[i].area * adjust / Geometry.area(p);
        });
        tdist = 0;
        sites = polygons.map(function(p, j) {
          var c = $C(0, 0), totalW = 0;
          $.each(p, function(v, i) {
            var poly = [sites[j], v, p[i + 1] || p[0]],
                targetPascal = (v.attached) ? pascal[v.attached[0]] : 1,
                w = Geometry.area(poly) * Math.exp((pascal[j] - targetPascal) * 2);
            totalW += w;
            c.$add(v.add(poly[2]).scale(0.5 * w));
          });
          c.$scale(1 / totalW);
          c.area = sites[j].area;
          tdist += Geometry.dist(c, sites[j]);
          return c;
        });
      }
      var s = 0, s2 = 0;
      $.each(pascal, function(p, i) {
        s += p;
        s2 += p * p;
      });
  //    console.log('to ' + (s2 - s * s / pascal.length) / pascal.length);
      return sites;
    },
  
    byArea : function(sites, bound) {
      sites = this.centroid(sites, bound);
      var tw = 0, iter = 0, polygons, pressure, polygons;
      $jit.util.each(sites, function(s) {
        tw += s.area;
      });
      tw = Geometry.area(bound) / tw;
      for (; iter < 100; iter++) {
        polygons = Geometry.voronoi(sites, bound);
        for (var j = 0; j < sites.length; j++) {
          if (polygons[j].length == 0) {
            sites = polygons.map(function(p, j) {
              return Geometry.centroid(p);
            });
            // iter = 1;
            break;
          }
        }
        pressure = polygons.map(function(p, ind) {
          return p.area * tw / (Geometry.area(p) + 1e-10);
        });
        polygons = Geometry.voronoi(sites, bound);
        sites = polygons.map(function(p, ind) {
          var po = $C(sites[ind].x, sites[ind].y), totalPressure, i;
          po.area = sites[ind].area;
          totalPressure = $C(0, 0);
          $jit.util.each(p, function(v, i) {
            var target = (v.attached) ? v.attached : -1,
                targetPressure = (v.attached) ? pressure[v.attached[0]] : 1,
                start = v,
                stop = p[i + 1] || p[0],
                pr = (pressure[ind] - targetPressure),
                dx = stop.x - start.x,
                dy = stop.y - start.y;
            totalPressure.x += dy * pr;
            totalPressure.y -= dx * pr;
          });
          po.x += totalPressure.x / 10;
          po.y += totalPressure.y / 10;
          po.tp = totalPressure;
          return po;
        });
      }
      return sites;
    }
  });
  
  
  /*
   * File: Treemap.js
   *
  */
  
  $jit.TM = {};
  
  var TM = $jit.TM;
  
  $jit.TM.$extend = true;
  
  /*
    Class: TM.Base
    
    Abstract class providing base functionality for <TM.Squarified>, <TM.Strip> and <TM.SliceAndDice> visualizations.
    
    Implements:
    
    All <Loader> methods
    
    Constructor Options:
    
    Inherits options from
    
    - <Options.Canvas>
    - <Options.Controller>
    - <Options.Node>
    - <Options.Edge>
    - <Options.Label>
    - <Options.Events>
    - <Options.Tips>
    - <Options.NodeStyles>
    - <Options.Navigation>
    
    Additionally, there are other parameters and some default values changed
  
    orientation - (string) Default's *h*. Whether to set horizontal or vertical layouts. Possible values are 'h' and 'v'.
    titleHeight - (number) Default's *13*. The height of the title rectangle for inner (non-leaf) nodes.
    offset - (number) Default's *2*. Boxes offset.
    constrained - (boolean) Default's *false*. Whether to show the entire tree when loaded or just the number of levels specified by _levelsToShow_.
    levelsToShow - (number) Default's *3*. The number of levels to show for a subtree. This number is relative to the selected node.
    labelsToShow - describe the range of levels to show for labels of sub tree. Default's [0, -1].
    animate - (boolean) Default's *false*. Whether to animate transitions.
    Node.type - Described in <Options.Node>. Default's *rectangle*.
    duration - Described in <Options.Fx>. Default's *700*.
    fps - Described in <Options.Fx>. Default's *45*.
    
    
    Instance Properties:
    
    canvas - Access a <Canvas> instance.
    graph - Access a <Graph> instance.
    op - Access a <TM.Op> instance.
    fx - Access a <TM.Plot> instance.
    labels - Access a <TM.Label> interface implementation.
  
    Inspired by:
    
    Squarified Treemaps (Mark Bruls, Kees Huizing, and Jarke J. van Wijk) <http://www.win.tue.nl/~vanwijk/stm.pdf>
    
    Tree visualization with tree-maps: 2-d space-filling approach (Ben Shneiderman) <http://hcil.cs.umd.edu/trs/91-03/91-03.html>
    
     Note:
     
     This visualization was built and engineered from scratch, taking only the paper as inspiration, and only shares some features with the visualization described in the paper.
  
  */
  TM.Base = {
    layout: {
      orientation: "h",
      vertical: function(){
        return this.orientation == "v";
      },
      horizontal: function(){
        return this.orientation == "h";
      },
      change: function(){
        this.orientation = this.vertical()? "h" : "v";
      }
    },
  
    initialize: function(controller){
      var config = {
        orientation: "h",
        titleHeight: 13,
        offset: 2,
        levelsToShow: 0,
        labelsToShow: [0, -1],
        constrained: false,
        animate: false,
        Node: {
          type: 'rectangle',
          overridable: true,
          //we all know why this is not zero,
          //right, Firefox?
          width: 3,
          height: 3,
          color: '#444',
          props: 'node-property:width:height'
        },
        Label: {
          textAlign: 'center',
          textBaseline: 'top'
        },
        Edge: {
          type: 'none'
        },
        duration: 700,
        fps: 45
      };
  
      this.controller = this.config = $.merge(Options("Canvas", "Node", "Edge",
          "Fx", "Controller", "Tips", "NodeStyles", "Events", "Navigation", "Label"), config, controller);
      this.layout.orientation = this.config.orientation;
  
      var canvasConfig = this.config;
      if (canvasConfig.useCanvas) {
        this.canvas = canvasConfig.useCanvas;
        this.config.labelContainer = this.canvas.id + '-label';
      } else {
        if(canvasConfig.background) {
          canvasConfig.background = $.merge({
            type: 'Circles'
          }, canvasConfig.background);
        }
        this.canvas = new Canvas(this, canvasConfig);
        this.config.labelContainer = (
          typeof canvasConfig.injectInto == 'string'? 
          canvasConfig.injectInto : 
          canvasConfig.injectInto.id) + '-label';
      }
  
      this.graphOptions = {
        'klass': Complex,
        'Node': {
          'selected': false,
          'exist': true,
          'drawn': true
        }
      };
      this.graph = new Graph(this.graphOptions, this.config.Node,
          this.config.Edge);
      this.labels = new TM.Label[canvasConfig.Label.type](this);
      this.fx = new TM.Plot(this);
      this.op = new TM.Op(this);
      this.group = new TM.Group(this);
      this.geom = new TM.Geom(this);
      this.clickedNode = null;
      this.busy = false;
      // initialize extras
      this.initializeExtras();
    },
  
    /* 
      Method: refresh 
      
      Computes positions and plots the tree.
    */
    refresh: function(){
      if(this.busy) return;
      this.busy = true;
      var that = this;
      if(this.config.animate) {
        this.compute('end');
        this.geom.setRightLevelToShow(this.graph.getNode(this.clickedNode
            && this.clickedNode.id || this.root));
        this.fx.animate($.merge(this.config, {
          modes: ['linear', this.config.Node.props],
          onComplete: function() {
            that.busy = false;
          }
        }));
      } else {
        var labelType = this.config.Label.type;
        if(labelType != 'Native') {
          this.graph.eachNode(function(n) { that.labels.hideLabel(n, false); });
        }
        this.busy = false;
        this.compute();
        this.geom.setRightLevelToShow(this.graph.getNode(this.clickedNode 
            && this.clickedNode.id || this.root));
        this.plot();
      }
    },
  
    /* 
      Method: plot 
      
      Plots the TreeMap. This is a shortcut to *fx.plot*. 
    
     */
    plot: function(){
      this.fx.plot();
    },
  
    /* 
    Method: leaf 
    
    Returns whether the node is a leaf.
    
     Parameters:
     
     n - (object) A <Graph.Node>.
  
   */
    leaf: function(n){
      return n.getSubnodes([
          1, 1
      ], "ignore").length == 0;
    },
    
    /* 
    Method: enter 
    
    Sets the node as root.
    
     Parameters:
     
     n - (object) A <Graph.Node>.
  
   */
    enter: function(n){
      if(this.busy) return;
      this.busy = true;
      var that = this,
          config = this.config,
          graph = this.graph,
          clickedNode = n,
          previousClickedNode = this.clickedNode;
  
      var callback = {
        onComplete: function() {
          //ensure that nodes are shown for that level
          that.geom.setRightLevelToShow(n);
          
          //compute positions of newly inserted nodes
          if(config.request) that.compute();
          if(config.animate) {
            //fade nodes
            graph.nodeList.setData('alpha', 0, 'end');
            n.eachSubgraph(function(n) {
              n.setData('alpha', 1, 'end');
              n.selected = false;
            }, "ignore");
            clickedNode.selected = true;
            that.fx.animate({
              duration: that.config.duration / 3,
              modes:['node-property:alpha'],
              onComplete: function() {
                //compute end positions
                that.clickedNode = clickedNode;
                that.compute('end');
                //animate positions
                //TODO(nico) commenting this line didn't seem to throw errors...
                that.clickedNode = previousClickedNode;
                that.fx.animate({
                  duration: 2 * that.config.duration / 3,
                  modes:['linear', that.config.Node.props],
                  onComplete: function() { 
                    that.busy = false;
                    //TODO(nico) check comment above
                    that.clickedNode = clickedNode;
                    that.geom.setRightLevelToShow(clickedNode);
                  }
                });
              }
            });
          } else {
            that.busy = false;
            that.clickedNode = n;
            that.refresh();
          }
        }
      };
      this.geom.setRightLevelToShow(n);
      if(config.request) {
        this.requestNodes(clickedNode, callback);
      } else {
        callback.onComplete();
      }
    },
  
    /* 
    Method: out 
    
    Sets the parent node of the current selected node as root.
  
   */
    out: function(){
      if(this.busy) return;
      this.busy = true;
      this.events.hoveredNode = false;
      var that = this,
          config = this.config,
          graph = this.graph,
          parents = graph.getNode(this.clickedNode 
              && this.clickedNode.id || this.root).getParents(),
          parent = parents[0],
          clickedNode = parent,
          previousClickedNode = this.clickedNode;
      
      //if no parents return
      if(!parent) {
        this.busy = false;
        return;
      }
      parent.selected = true;
      
      //final plot callback
      var callback = {
        onComplete: function() {
          previousClickedNode.selected = false;
          that.clickedNode = parent;
          if(config.request) {
            that.requestNodes(parent, {
              onComplete: function() {
                that.compute();
                that.plot();
                that.busy = false;
              }
            });
          } else {
            that.compute();
            that.plot();
            that.busy = false;
          }
          that.geom.setRightLevelToShow(parent);
          that.plot();
        }
      };
      //prune tree
      this.geom.setRightLevelToShow(parent);
      //animate node positions
      if(config.animate) {
        this.clickedNode = clickedNode;
        this.compute('end');
        //animate the visible subtree only
        this.clickedNode = previousClickedNode;
        this.fx.animate({
          duration: 2 * this.config.duration / 3,
          modes:['linear', this.config.Node.props],
          onComplete: function() {
            //animate the parent subtree
            that.clickedNode = clickedNode;
            //change nodes alpha
            clickedNode.eachSubgraph(function(n) {
              n.setDataset(['current', 'end'], {
                'alpha': [0, 1]
              });
            }, "ignore");
            previousClickedNode.eachSubgraph(function(node) {
              node.setData('alpha', 1);
            }, "ignore");
            that.geom.setRightLevelToShow(parent);
            that.fx.animate({
              duration: that.config.duration / 3,
              modes:['node-property:alpha'],
              onComplete: function() {
                callback.onComplete();
              }
            });
          }
        });
      } else {
        callback.onComplete();
      }
    },
  
    requestNodes: function(node, onComplete){
      var handler = $.merge(this.controller, onComplete), 
          lev = this.config.levelsToShow;
      if (handler.request) {
        var leaves = [], d = node._depth;
        node.eachLevel(0, lev, function(n){
          var nodeLevel = lev - (n._depth - d);
          if (n.drawn && !n.anySubnode() && nodeLevel > 0) {
            leaves.push(n);
            n._level = nodeLevel;
          }
        });
        this.group.requestNodes(leaves, handler);
      } else {
        handler.onComplete();
      }
    },
    
    reposition: function() {
      this.compute('end');
    }
  };
  
  
  /*
    Class: TM.Op
    
    Custom extension of <Graph.Op>.
    
    Extends:
    
    All <Graph.Op> methods
    
    See also:
    
    <Graph.Op>
    
    */
  TM.Op = new Class({
    Implements: Graph.Op,
  
    initialize: function(viz){
      this.viz = viz;
    }
  });
  
  //extend level methods of Graph.Geom
  TM.Geom = new Class({
    Implements: Graph.Geom,
    
    getRightLevelToShow: function() {
      return this.viz.config.levelsToShow;
    },
    
    setRightLevelToShow: function(node) {
      var level = this.getRightLevelToShow(),
          labelRange = this.viz.config.labelsToShow,
          fx = this.viz.labels;
      var dump = {};
      node.eachLevel(0, false, function(n) {
        var d = n._depth - node._depth;
        n._hideLabel = labelRange[0] >= 0 && d < labelRange[0] || labelRange[1] >= 0 && d > labelRange[1];
        if(level > 0 && d > level) {
          n.drawn = false; 
          n.exist = false;
          n.ignore = true;
          fx.hideLabel(n, false);
        } else {
          n.drawn = true;
          n.exist = true;
          delete n.ignore;
        }
        dump[n.name] = n._hideLabel;
      });
      node.drawn = true;
      delete node.ignore;
    }
  });
  
  /*
  
  Performs operations on group of nodes.
  
  */
  TM.Group = new Class( {
  
    initialize: function(viz){
      this.viz = viz;
      this.canvas = viz.canvas;
      this.config = viz.config;
    },
  
    /*
    
      Calls the request method on the controller to request a subtree for each node. 
    */
    requestNodes: function(nodes, controller){
      var counter = 0, len = nodes.length, nodeSelected = {};
      var complete = function(){
        controller.onComplete();
      };
      var viz = this.viz;
      if (len == 0)
        complete();
      for ( var i = 0; i < len; i++) {
        nodeSelected[nodes[i].id] = nodes[i];
        controller.request(nodes[i].id, nodes[i]._level, {
          onComplete: function(nodeId, data){
            if (data && data.children) {
              data.id = nodeId;
              viz.op.sum(data, {
                type: 'nothing'
              });
            }
            if (++counter == len) {
              viz.graph.computeLevels(viz.root, 0);
              complete();
            }
          }
        });
      }
    }
  });
  
  /*
    Class: TM.Plot
    
    Custom extension of <Graph.Plot>.
    
    Extends:
    
    All <Graph.Plot> methods
    
    See also:
    
    <Graph.Plot>
    
    */
  TM.Plot = new Class({
  
    Implements: Graph.Plot,
  
    initialize: function(viz){
      this.viz = viz;
      this.config = viz.config;
      this.node = this.config.Node;
      this.edge = this.config.Edge;
      this.animation = new Animation;
      this.nodeTypes = new TM.Plot.NodeTypes;
      this.edgeTypes = new TM.Plot.EdgeTypes;
      this.labels = viz.labels;
    },
  
    plot: function(opt, animating){
      var viz = this.viz, 
          graph = viz.graph;
      viz.canvas.clear();
      this.plotTree(graph.getNode(viz.clickedNode && viz.clickedNode.id || viz.root), $.merge(viz.config, opt || {}, {
        'withLabels': true,
        'hideLabels': false,
        'plotSubtree': function(n, ch){
          return n.anySubnode("exist");
        }
      }), animating);
    }
  });
  
  /*
    Class: TM.Label
    
    Custom extension of <Graph.Label>. 
    Contains custom <Graph.Label.SVG>, <Graph.Label.HTML> and <Graph.Label.Native> extensions.
  
    Extends:
  
    All <Graph.Label> methods and subclasses.
  
    See also:
  
    <Graph.Label>, <Graph.Label.Native>, <Graph.Label.HTML>, <Graph.Label.SVG>.
    
  */
  TM.Label = {};
  
  TM.Label.HTML = new Class( {
  	  Implements: Graph.Label.HTML,
  
  	  initialize: function(viz){
  	    this.viz = viz;
  	    this.leaf = viz.leaf;
  	    this.config = viz.config;
  	  },
  
  	  /* 
  	    placeLabel
  	  
  	    Overrides abstract method placeLabel in <Graph.Plot>.
  	  
  	    Parameters:
  	  
  	    tag - A DOM label element.
  	    node - A <Graph.Node>.
  	    controller - A configuration/controller object passed to the visualization.
  	  
  	  */
  	  placeLabel: function(tag, node, controller){
  	    controller = controller || this.viz.controller;
  	    var pos = node.pos.getc(true),
  	        canvas = this.viz.canvas,
  	        ox = canvas.translateOffsetX,
  	        oy = canvas.translateOffsetY,
  	        sx = canvas.scaleOffsetX,
  	        sy = canvas.scaleOffsetY,
  	        radius = canvas.getSize(),
  	        width = node.getData('width') - 2,
  	        height = node.getData('height') -2;
  	    
  	    var labelPos = {
  	      x: Math.round(pos.x * sx + ox + radius.width / 2),
  	      y: Math.round(pos.y * sy + oy + radius.height / 2)
  	    };
  
  	    var style = tag.style;
  	    style.left = labelPos.x + 'px';
  	    style.top = labelPos.y + 'px';
  	    style.width = width * sx + 'px';
  	    style.height = height * sy + 'px';
  	    style.zIndex = node._depth * 100;
  	    style.display = '';
  
  	    if(node._hideLabel || (width < 15 || height < 15) || !this.leaf(node) && !this.config.titleHeight) {
  	      tag.style.display = 'none';
  	    }
  	    controller.onPlaceLabel(tag, node);
  	  }
  	});
  
  /*
   TM.Label.Native
  
   Custom extension of <Graph.Label.Native>.
  
   Extends:
  
   All <Graph.Label.Native> methods
  
   See also:
  
   <Graph.Label.Native>
  */
  TM.Label.Native = new Class({
    Implements: Graph.Label.Native,
  
    initialize: function(viz) {
      this.config = viz.config;
      this.leaf = viz.leaf;
    },
    
    renderLabel: function(canvas, node, controller) {
      if(node._hideLabel || !this.leaf(node) && !this.config.titleHeight) return;
      var pos = node.pos.getc(true), 
          ctx = canvas.getCtx(),
          width = node.getData('width'),
          height = node.getData('height'),
          x = pos.x + width / 2,
          y = pos.y;
        if (false && (isNaN(width) || width === 0 || width < 25)) {
          return;
        } else {
      	ctx.save();
      	ctx.shadowBlur = 5;
      	ctx.shadowColor = 'black';
      	
          ctx.fillText(node.name, x, y);//, width);
          ctx.restore();
        }
    }
  });
  
  /*
    Class: TM.Plot.NodeTypes
  
    This class contains a list of <Graph.Node> built-in types. 
    Node types implemented are 'none', 'rectangle'.
  
    You can add your custom node types, customizing your visualization to the extreme.
  
    Example:
  
    (start code js)
      TM.Plot.NodeTypes.implement({
        'mySpecialType': {
          'render': function(node, canvas) {
            //print your custom node to canvas
          },
          //optional
          'contains': function(node, pos) {
            //return true if pos is inside the node or false otherwise
          }
        }
      });
    (end code)
  
  */
  TM.Plot.NodeTypes = new Class( {
    'none': {
      'render': $.empty
    },
  
    'rectangle': {
      'render': function(node, canvas, animating){
        var leaf = this.viz.leaf(node),
            config = this.config,
            offst = config.offset,
            titleHeight = config.titleHeight,
            pos = node.pos.getc(true),
            width = node.getData('width'),
            height = node.getData('height'),
            border = node.getData('border'),
            ctx = canvas.getCtx(),
            posx = pos.x + offst / 2, 
            posy = pos.y + offst / 2;
        if(width <= offst || height <= offst) return;
        if (leaf) {
          if(config.cushion) {
            var lg = ctx.createRadialGradient(posx + (width-offst)/2, posy + (height-offst)/2, 1, 
                posx + (width-offst)/2, posy + (height-offst)/2, width < height? height : width);
            var color = node.getData('color');
            var colorGrad = $.rgbToHex($.map($.hexToRgb(color), 
                function(r) { return r * 0.2 >> 0; }));
            lg.addColorStop(0, color);
            lg.addColorStop(1, colorGrad);
            ctx.fillStyle = lg;
          }
          ctx.fillRect(posx, posy, width - offst, height - offst);
          if(border) {
            ctx.save();
            ctx.strokeStyle = border;
            ctx.strokeRect(posx, posy, width - offst, height - offst);
            ctx.restore();
          }
        } else if(titleHeight > 0){
          ctx.fillRect(pos.x + offst / 2, pos.y + offst / 2, width - offst,
              titleHeight - offst);
          if(border) {
            ctx.save();
            ctx.strokeStyle = border;
            ctx.strokeRect(pos.x + offst / 2, pos.y + offst / 2, width - offst,
                height - offst);
            ctx.restore();
          }
        }
      },
      'contains': function(node, pos) {
        if(this.viz.clickedNode && !node.isDescendantOf(this.viz.clickedNode.id) || node.ignore) return false;
        var npos = node.pos.getc(true),
            width = node.getData('width'), 
            leaf = this.viz.leaf(node),
            height = leaf? node.getData('height') : this.config.titleHeight;
        return this.nodeHelper.rectangle.contains({x: npos.x + width/2, y: npos.y + height/2}, pos, width, height);
      }
    }
  });
  
  TM.Plot.EdgeTypes = new Class( {
    'none': $.empty
  });
  
  /*
    Class: TM.SliceAndDice
    
    A slice and dice TreeMap visualization.
    
    Implements:
    
    All <TM.Base> methods and properties.
  */
  TM.SliceAndDice = new Class( {
    Implements: [
        Loader, Extras, TM.Base, Layouts.TM.SliceAndDice
    ]
  });
  
  /*
    Class: TM.Squarified
    
    A squarified TreeMap visualization.
  
    Implements:
    
    All <TM.Base> methods and properties.
  */
  TM.Squarified = new Class( {
    Implements: [
        Loader, Extras, TM.Base, Layouts.TM.Squarified
    ]
  });
  
  /*
    Class: TM.Strip
    
    A strip TreeMap visualization.
  
    Implements:
    
    All <TM.Base> methods and properties.
  */
  TM.Strip = new Class( {
    Implements: [
        Loader, Extras, TM.Base, Layouts.TM.Strip
    ]
  });
  
  
  /**
   *
   * @author ZHANG BEi
   */
  
  
  /**
   * @class TM.Plot.NodeTypes.polygon
   */
  TM.Plot.NodeTypes.implement({
    polygon: {
      /**
       *
       * @param {Node} node
       * @param {Canvas} canvas
       * @param {Boolean} animating
       */
      'render' : function(node, canvas, animating) {
        var leaf = this.viz.leaf(node),
            config = this.config,
            border = node.getData('border'),
            vertices = node.getData('vertices'),
            ctx = canvas.getCtx(),
            titleHeight = config.titleHeight,
            offset = config.offset,
            i;
        if (!vertices || vertices.length === 0) {
          return;
        }
        var pts = vertices.slice(0);
        if (Geometry.area(pts) < 0) {
          pts.reverse();
        }
        if (leaf) {
          ctx.lineJoin = "bevel";
          if (config.cushion) {
            var center = Geometry.centroid(pts), 
                x = 0, 
                y = 0, 
                minX = pts[0].x, 
                maxX = pts[0].x, 
                minY = pts[0].y, 
                maxY = pts[0].y,
                dist, maxDist;
  
            for (i = 0; i < pts.length; i++) {
              x += pts[i].x;
              y += pts[i].y;
            }
  
            x /= pts.length;
            y /= pts.length;
  
            for (i = 0; i < pts.length; i++) {
              dist = Math.sqrt((x - pts[i].x) * (x - pts[i].x) + (y - pts[i].y) * (y - pts[i].y));
              if (!maxDist) {
                maxDist = dist;
              } else {
                maxDist = maxDist < dist ? dist : maxDist;
              }
            }
            var width = maxX - minX + 1, height = maxY - minY + 1,
                lg = ctx.createRadialGradient(x, y, 1, x, y, maxDist),
                color = node.getData('color'),
                colorGrad = $.rgbToHex($.map($.hexToRgb(color), function(r) {
                  return r * 0.5 >> 0;
                }));
            lg.addColorStop(0, color);
            lg.addColorStop(1, colorGrad);
            ctx.fillStyle = lg;
          }
          
          // Fill polygon
          ctx.beginPath();
          ctx.moveTo(pts[0].x, pts[0].y);
          for (i = 1; i < pts.length; i++) {
            ctx.lineTo(pts[i].x, pts[i].y);
          }
          ctx.closePath();
          ctx.fill();
          if (border) {
            ctx.save();
            ctx.strokeStyle = border;
            ctx.stroke();
            ctx.restore();
          }
        } else if (titleHeight > 0) {
          pts = Geometry.offsetConvex(pts, -offset * 0.5);
          if (!pts.length) {
            pts = [pts];
          }
          // Fill polygon
          ctx.beginPath();
          ctx.moveTo(pts[0].x, pts[0].y);
          for (i = 1; i < pts.length; i++) {
            ctx.lineTo(pts[i].x, pts[i].y);
          }
          ctx.lineTo(pts[0].x, pts[0].y);
          ctx.closePath();
          ctx.save();
          ctx.lineWidth = config.offset;
          ctx.stroke();
          ctx.restore();
  
        }
      },
  
      'contains' : function(node, pos) {
        var config = this.config, curr, vert, ivert;
        if (node.ignore || node.getData('alpha') < 1) {
          return false;
        }
        curr = this.viz.clickedNode ? this.viz.clickedNode.id : this.viz.root;
        curr = this.viz.graph.getNode(curr);
        if (this.config.levelsToShow) {
          if (!(node._depth > curr._depth &&
              node._depth <= curr._depth + this.config.levelsToShow)) {
            return false;
          }
        } else if (node._depth <= curr._depth) {
          return false;
        }
  
        vert = node.getData('vertices');
        if (!vert) {
          return false;
        }
  
        // if (node.getParents().length == 0
        // || node.getParents()[0].id != curr)
        // return false;
        if (config.levelsToShow && node._depth < curr._depth + config.levelsToShow
            || !config.levelsToShow && node.getSubnodes([ 1, 1 ]).length) {
          if (config.offset == 0) {
            return false;
          }
          return Geometry.pointInPolygon([ pos ], node.getData('vertices'))[0];
  //        ivert = Geometry.offsetConvex(vert, -config.offset * 2);
  //        return Geometry.pointInPolygon([ pos ], vert)[0] && !Geometry.pointInPolygon([ pos ], ivert)[0];
        }
        return Geometry.pointInPolygon([ pos ], node.getData('vertices'))[0];
      }
    }
  });
  
  /*
   * Class: TM.Voronoi
   * 
   * A Voronoi TreeMap visualization.
   * 
   * Implements:
   * 
   * All <TM.Base> methods and properties.
   */
  TM.Voronoi = new Class({
    Implements : [ Loader, Extras, TM.Base, Layouts.TM.Voronoi ],
    initialize : function(controller) {
      var config = {
        centroidType : "weightedCentroid",
        Node : {
          type : 'polygon',
          props : 'node-property:width:height:vertices'
        },
        Label : {
          textBaseline : 'middle',
          type : 'Native'
        }
      };
  
      this.controller = this.config = $.merge(config, controller);
      TM.Base.initialize.apply(this, [ this.controller ]);
    }
  });
  
  
  
  
   })();
  