text: /*global window: false */
  
  /*global document: false */
  
  "use strict";
  
  
  
  var color = require('chartjs-color');
  
  
  
  module.exports = function(Chart) {
  
  
  
  	//Global Chart helpers object for utility methods and classes
  
  	var helpers = Chart.helpers = {};
  
  
  
  	//-- Basic js utility methods
  
  	helpers.each = function(loopable, callback, self, reverse) {
  
  		// Check to see if null or undefined firstly.
  
  		var i, len;
  
  		if (helpers.isArray(loopable)) {
  
  			len = loopable.length;
  
  			if (reverse) {
  
  				for (i = len - 1; i >= 0; i--) {
  
  					callback.call(self, loopable[i], i);
  
  				}
  
  			} else {
  
  				for (i = 0; i < len; i++) {
  
  					callback.call(self, loopable[i], i);
  
  				}
  
  			}
  
  		} else if (typeof loopable === 'object') {
  
  			var keys = Object.keys(loopable);
  
  			len = keys.length;
  
  			for (i = 0; i < len; i++) {
  
  				callback.call(self, loopable[keys[i]], keys[i]);
  
  			}
  
  		}
  
  	};
  
  	helpers.clone = function(obj) {
  
  		var objClone = {};
  
  		helpers.each(obj, function(value, key) {
  
  			if (obj.hasOwnProperty(key)) {
  
  				if (helpers.isArray(value)) {
  
  					objClone[key] = value.slice(0);
  
  				} else if (typeof value === 'object' && value !== null) {
  
  					objClone[key] = helpers.clone(value);
  
  				} else {
  
  					objClone[key] = value;
  
  				}
  
  			}
  
  		});
  
  		return objClone;
  
  	};
  
  	helpers.extend = function(base) {
  
  		var len = arguments.length;
  
  		var additionalArgs = [];
  
  		for (var i = 1; i < len; i++) {
  
  			additionalArgs.push(arguments[i]);
  
  		}
  
  		helpers.each(additionalArgs, function(extensionObject) {
  
  			helpers.each(extensionObject, function(value, key) {
  
  				if (extensionObject.hasOwnProperty(key)) {
  
  					base[key] = value;
  
  				}
  
  			});
  
  		});
  
  		return base;
  
  	};
  
  	// Need a special merge function to chart configs since they are now grouped
  
  	helpers.configMerge = function(_base) {
  
  		var base = helpers.clone(_base);
  
  		helpers.each(Array.prototype.slice.call(arguments, 1), function(extension) {
  
  			helpers.each(extension, function(value, key) {
  
  				if (extension.hasOwnProperty(key)) {
  
  					if (key === 'scales') {
  
  						// Scale config merging is complex. Add out own function here for that
  
  						base[key] = helpers.scaleMerge(base.hasOwnProperty(key) ? base[key] : {}, value);
  
  
  
  					} else if (key === 'scale') {
  
  						// Used in polar area & radar charts since there is only one scale
  
  						base[key] = helpers.configMerge(base.hasOwnProperty(key) ? base[key] : {}, Chart.scaleService.getScaleDefaults(value.type), value);
  
  					} else if (base.hasOwnProperty(key) && helpers.isArray(base[key]) && helpers.isArray(value)) {
  
  						// In this case we have an array of objects replacing another array. Rather than doing a strict replace,
  
  						// merge. This allows easy scale option merging
  
  						var baseArray = base[key];
  
  
  
  						helpers.each(value, function(valueObj, index) {
  
  
  
  							if (index < baseArray.length) {
  
  								if (typeof baseArray[index] === 'object' && baseArray[index] !== null && typeof valueObj === 'object' && valueObj !== null) {
  
  									// Two objects are coming together. Do a merge of them.
  
  									baseArray[index] = helpers.configMerge(baseArray[index], valueObj);
  
  								} else {
  
  									// Just overwrite in this case since there is nothing to merge
  
  									baseArray[index] = valueObj;
  
  								}
  
  							} else {
  
  								baseArray.push(valueObj); // nothing to merge
  
  							}
  
  						});
  
  
  
  					} else if (base.hasOwnProperty(key) && typeof base[key] === "object" && base[key] !== null && typeof value === "object") {
  
  						// If we are overwriting an object with an object, do a merge of the properties.
  
  						base[key] = helpers.configMerge(base[key], value);
  
  
  
  					} else {
  
  						// can just overwrite the value in this case
  
  						base[key] = value;
  
  					}
  
  				}
  
  			});
  
  		});
  
  
  
  		return base;
  
  	};
  
  	helpers.extendDeep = function(_base) {
  
  		return _extendDeep.apply(this, arguments);
  
  
  
  		function _extendDeep(dst) {
  
  			helpers.each(arguments, function(obj) {
  
  				if (obj !== dst) {
  
  					helpers.each(obj, function(value, key) {
  
  						if (dst[key] && dst[key].constructor && dst[key].constructor === Object) {
  
  							_extendDeep(dst[key], value);
  
  						} else {
  
  							dst[key] = value;
  
  						}
  
  					});
  
  				}
  
  			});
  
  			return dst;
  
  		}
  
  	};
  
  	helpers.scaleMerge = function(_base, extension) {
  
  		var base = helpers.clone(_base);
  
  
  
  		helpers.each(extension, function(value, key) {
  
  			if (extension.hasOwnProperty(key)) {
  
  				if (key === 'xAxes' || key === 'yAxes') {
  
  					// These properties are arrays of items
  
  					if (base.hasOwnProperty(key)) {
  
  						helpers.each(value, function(valueObj, index) {
  
  							var axisType = helpers.getValueOrDefault(valueObj.type, key === 'xAxes' ? 'category' : 'linear');
  
  							var axisDefaults = Chart.scaleService.getScaleDefaults(axisType);
  
  							if (index >= base[key].length || !base[key][index].type) {
  
  								base[key].push(helpers.configMerge(axisDefaults, valueObj));
  
  							} else if (valueObj.type && valueObj.type !== base[key][index].type) {
  
  								// Type changed. Bring in the new defaults before we bring in valueObj so that valueObj can override the correct scale defaults
  
  								base[key][index] = helpers.configMerge(base[key][index], axisDefaults, valueObj);
  
  							} else {
  
  								// Type is the same
  
  								base[key][index] = helpers.configMerge(base[key][index], valueObj);
  
  							}
  
  						});
  
  					} else {
  
  						base[key] = [];
  
  						helpers.each(value, function(valueObj) {
  
  							var axisType = helpers.getValueOrDefault(valueObj.type, key === 'xAxes' ? 'category' : 'linear');
  
  							base[key].push(helpers.configMerge(Chart.scaleService.getScaleDefaults(axisType), valueObj));
  
  						});
  
  					}
  
  				} else if (base.hasOwnProperty(key) && typeof base[key] === "object" && base[key] !== null && typeof value === "object") {
  
  					// If we are overwriting an object with an object, do a merge of the properties.
  
  					base[key] = helpers.configMerge(base[key], value);
  
  
  
  				} else {
  
  					// can just overwrite the value in this case
  
  					base[key] = value;
  
  				}
  
  			}
  
  		});
  
  
  
  		return base;
  
  	};
  
  	helpers.getValueAtIndexOrDefault = function(value, index, defaultValue) {
  
  		if (value === undefined || value === null) {
  
  			return defaultValue;
  
  		}
  
  
  
  		if (helpers.isArray(value)) {
  
  			return index < value.length ? value[index] : defaultValue;
  
  		}
  
  
  
  		return value;
  
  	};
  
  	helpers.getValueOrDefault = function(value, defaultValue) {
  
  		return value === undefined ? defaultValue : value;
  
  	};
  
  	helpers.indexOf = function(arrayToSearch, item) {
  
  		if (Array.prototype.indexOf) {
  
  			return arrayToSearch.indexOf(item);
  
  		} else {
  
  			for (var i = 0; i < arrayToSearch.length; i++) {
  
  				if (arrayToSearch[i] === item)
  
  					return i;
  
  			}
  
  			return -1;
  
  		}
  
  	};
  
  	helpers.where = function(collection, filterCallback) {
  
  		var filtered = [];
  
  
  
  		helpers.each(collection, function(item) {
  
  			if (filterCallback(item)) {
  
  				filtered.push(item);
  
  			}
  
  		});
  
  
  
  		return filtered;
  
  	};
  
  	helpers.findIndex = function(arrayToSearch, callback, thisArg) {
  
  		var index = -1;
  
  		if (Array.prototype.findIndex) {
  
  			index = arrayToSearch.findIndex(callback, thisArg);
  
  		} else {
  
  			for (var i = 0; i < arrayToSearch.length; ++i) {
  
  				thisArg = thisArg !== undefined ? thisArg : arrayToSearch;
  
  
  
  				if (callback.call(thisArg, arrayToSearch[i], i, arrayToSearch)) {
  
  					index = i;
  
  					break;
  
  				}
  
  			}
  
  		}
  
  
  
  		return index;
  
  	};
  
  	helpers.findNextWhere = function(arrayToSearch, filterCallback, startIndex) {
  
  		// Default to start of the array
  
  		if (startIndex === undefined || startIndex === null) {
  
  			startIndex = -1;
  
  		}
  
  		for (var i = startIndex + 1; i < arrayToSearch.length; i++) {
  
  			var currentItem = arrayToSearch[i];
  
  			if (filterCallback(currentItem)) {
  
  				return currentItem;
  
  			}
  
  		}
  
  	};
  
  	helpers.findPreviousWhere = function(arrayToSearch, filterCallback, startIndex) {
  
  		// Default to end of the array
  
  		if (startIndex === undefined || startIndex === null) {
  
  			startIndex = arrayToSearch.length;
  
  		}
  
  		for (var i = startIndex - 1; i >= 0; i--) {
  
  			var currentItem = arrayToSearch[i];
  
  			if (filterCallback(currentItem)) {
  
  				return currentItem;
  
  			}
  
  		}
  
  	};
  
  	helpers.inherits = function(extensions) {
  
  		//Basic javascript inheritance based on the model created in Backbone.js
  
  		var parent = this;
  
  		var ChartElement = (extensions && extensions.hasOwnProperty("constructor")) ? extensions.constructor : function() {
  
  			return parent.apply(this, arguments);
  
  		};
  
  
  
  		var Surrogate = function() {
  
  			this.constructor = ChartElement;
  
  		};
  
  		Surrogate.prototype = parent.prototype;
  
  		ChartElement.prototype = new Surrogate();
  
  
  
  		ChartElement.extend = helpers.inherits;
  
  
  
  		if (extensions) {
  
  			helpers.extend(ChartElement.prototype, extensions);
  
  		}
  
  
  
  		ChartElement.__super__ = parent.prototype;
  
  
  
  		return ChartElement;
  
  	};
  
  	helpers.noop = function() {};
  
  	helpers.uid = (function() {
  
  		var id = 0;
  
  		return function() {
  
  			return id++;
  
  		};
  
  	})();
  
  	helpers.warn = function(str) {
  
  		//Method for warning of errors
  
  		if (console && typeof console.warn === "function") {
  
  			console.warn(str);
  
  		}
  
  	};
  
  	//-- Math methods
  
  	helpers.isNumber = function(n) {
  
  		return !isNaN(parseFloat(n)) && isFinite(n);
  
  	};
  
  	helpers.almostEquals = function(x, y, epsilon) {
  
  		return Math.abs(x - y) < epsilon;
  
  	};
  
  	helpers.max = function(array) {
  
  		return array.reduce(function(max, value) {
  
  			if (!isNaN(value)) {
  
  				return Math.max(max, value);
  
  			} else {
  
  				return max;
  
  			}
  
  		}, Number.NEGATIVE_INFINITY);
  
  	};
  
  	helpers.min = function(array) {
  
  		return array.reduce(function(min, value) {
  
  			if (!isNaN(value)) {
  
  				return Math.min(min, value);
  
  			} else {
  
  				return min;
  
  			}
  
  		}, Number.POSITIVE_INFINITY);
  
  	};
  
  	helpers.sign = function(x) {
  
  		if (Math.sign) {
  
  			return Math.sign(x);
  
  		} else {
  
  			x = +x; // convert to a number
  
  			if (x === 0 || isNaN(x)) {
  
  				return x;
  
  			}
  
  			return x > 0 ? 1 : -1;
  
  		}
  
  	};
  
  	helpers.log10 = function(x) {
  
  		if (Math.log10) {
  
  			return Math.log10(x);
  
  		} else {
  
  			return Math.log(x) / Math.LN10;
  
  		}
  
  	};
  
  	helpers.toRadians = function(degrees) {
  
  		return degrees * (Math.PI / 180);
  
  	};
  
  	helpers.toDegrees = function(radians) {
  
  		return radians * (180 / Math.PI);
  
  	};
  
  	// Gets the angle from vertical upright to the point about a centre.
  
  	helpers.getAngleFromPoint = function(centrePoint, anglePoint) {
  
  		var distanceFromXCenter = anglePoint.x - centrePoint.x,
  
  			distanceFromYCenter = anglePoint.y - centrePoint.y,
  
  			radialDistanceFromCenter = Math.sqrt(distanceFromXCenter * distanceFromXCenter + distanceFromYCenter * distanceFromYCenter);
  
  
  
  		var angle = Math.atan2(distanceFromYCenter, distanceFromXCenter);
  
  
  
  		if (angle < (-0.5 * Math.PI)) {
  
  			angle += 2.0 * Math.PI; // make sure the returned angle is in the range of (-PI/2, 3PI/2]
  
  		}
  
  
  
  		return {
  
  			angle: angle,
  
  			distance: radialDistanceFromCenter
  
  		};
  
  	};
  
  	helpers.aliasPixel = function(pixelWidth) {
  
  		return (pixelWidth % 2 === 0) ? 0 : 0.5;
  
  	};
  
  	helpers.splineCurve = function(firstPoint, middlePoint, afterPoint, t) {
  
  		//Props to Rob Spencer at scaled innovation for his post on splining between points
  
  		//http://scaledinnovation.com/analytics/splines/aboutSplines.html
  
  
  
  		// This function must also respect "skipped" points
  
  
  
  		var previous = firstPoint.skip ? middlePoint : firstPoint,
  
  			current = middlePoint,
  
  			next = afterPoint.skip ? middlePoint : afterPoint;
  
  
  
  		var d01 = Math.sqrt(Math.pow(current.x - previous.x, 2) + Math.pow(current.y - previous.y, 2));
  
  		var d12 = Math.sqrt(Math.pow(next.x - current.x, 2) + Math.pow(next.y - current.y, 2));
  
  
  
  		var s01 = d01 / (d01 + d12);
  
  		var s12 = d12 / (d01 + d12);
  
  
  
  		// If all points are the same, s01 & s02 will be inf
  
  		s01 = isNaN(s01) ? 0 : s01;
  
  		s12 = isNaN(s12) ? 0 : s12;
  
  
  
  		var fa = t * s01; // scaling factor for triangle Ta
  
  		var fb = t * s12;
  
  
  
  		return {
  
  			previous: {
  
  				x: current.x - fa * (next.x - previous.x),
  
  				y: current.y - fa * (next.y - previous.y)
  
  			},
  
  			next: {
  
  				x: current.x + fb * (next.x - previous.x),
  
  				y: current.y + fb * (next.y - previous.y)
  
  			}
  
  		};
  
  	};
  
  	helpers.nextItem = function(collection, index, loop) {
  
  		if (loop) {
  
  			return index >= collection.length - 1 ? collection[0] : collection[index + 1];
  
  		}
  
  
  
  		return index >= collection.length - 1 ? collection[collection.length - 1] : collection[index + 1];
  
  	};
  
  	helpers.previousItem = function(collection, index, loop) {
  
  		if (loop) {
  
  			return index <= 0 ? collection[collection.length - 1] : collection[index - 1];
  
  		}
  
  		return index <= 0 ? collection[0] : collection[index - 1];
  
  	};
  
  	// Implementation of the nice number algorithm used in determining where axis labels will go
  
  	helpers.niceNum = function(range, round) {
  
  		var exponent = Math.floor(helpers.log10(range));
  
  		var fraction = range / Math.pow(10, exponent);
  
  		var niceFraction;
  
  
  
  		if (round) {
  
  			if (fraction < 1.5) {
  
  				niceFraction = 1;
  
  			} else if (fraction < 3) {
  
  				niceFraction = 2;
  
  			} else if (fraction < 7) {
  
  				niceFraction = 5;
  
  			} else {
  
  				niceFraction = 10;
  
  			}
  
  		} else {
  
  			if (fraction <= 1.0) {
  
  				niceFraction = 1;
  
  			} else if (fraction <= 2) {
  
  				niceFraction = 2;
  
  			} else if (fraction <= 5) {
  
  				niceFraction = 5;
  
  			} else {
  
  				niceFraction = 10;
  
  			}
  
  		}
  
  
  
  		return niceFraction * Math.pow(10, exponent);
  
  	};
  
  	//Easing functions adapted from Robert Penner's easing equations
  
  	//http://www.robertpenner.com/easing/
  
  	var easingEffects = helpers.easingEffects = {
  
  		linear: function(t) {
  
  			return t;
  
  		},
  
  		easeInQuad: function(t) {
  
  			return t * t;
  
  		},
  
  		easeOutQuad: function(t) {
  
  			return -1 * t * (t - 2);
  
  		},
  
  		easeInOutQuad: function(t) {
  
  			if ((t /= 1 / 2) < 1) {
  
  				return 1 / 2 * t * t;
  
  			}
  
  			return -1 / 2 * ((--t) * (t - 2) - 1);
  
  		},
  
  		easeInCubic: function(t) {
  
  			return t * t * t;
  
  		},
  
  		easeOutCubic: function(t) {
  
  			return 1 * ((t = t / 1 - 1) * t * t + 1);
  
  		},
  
  		easeInOutCubic: function(t) {
  
  			if ((t /= 1 / 2) < 1) {
  
  				return 1 / 2 * t * t * t;
  
  			}
  
  			return 1 / 2 * ((t -= 2) * t * t + 2);
  
  		},
  
  		easeInQuart: function(t) {
  
  			return t * t * t * t;
  
  		},
  
  		easeOutQuart: function(t) {
  
  			return -1 * ((t = t / 1 - 1) * t * t * t - 1);
  
  		},
  
  		easeInOutQuart: function(t) {
  
  			if ((t /= 1 / 2) < 1) {
  
  				return 1 / 2 * t * t * t * t;
  
  			}
  
  			return -1 / 2 * ((t -= 2) * t * t * t - 2);
  
  		},
  
  		easeInQuint: function(t) {
  
  			return 1 * (t /= 1) * t * t * t * t;
  
  		},
  
  		easeOutQuint: function(t) {
  
  			return 1 * ((t = t / 1 - 1) * t * t * t * t + 1);
  
  		},
  
  		easeInOutQuint: function(t) {
  
  			if ((t /= 1 / 2) < 1) {
  
  				return 1 / 2 * t * t * t * t * t;
  
  			}
  
  			return 1 / 2 * ((t -= 2) * t * t * t * t + 2);
  
  		},
  
  		easeInSine: function(t) {
  
  			return -1 * Math.cos(t / 1 * (Math.PI / 2)) + 1;
  
  		},
  
  		easeOutSine: function(t) {
  
  			return 1 * Math.sin(t / 1 * (Math.PI / 2));
  
  		},
  
  		easeInOutSine: function(t) {
  
  			return -1 / 2 * (Math.cos(Math.PI * t / 1) - 1);
  
  		},
  
  		easeInExpo: function(t) {
  
  			return (t === 0) ? 1 : 1 * Math.pow(2, 10 * (t / 1 - 1));
  
  		},
  
  		easeOutExpo: function(t) {
  
  			return (t === 1) ? 1 : 1 * (-Math.pow(2, -10 * t / 1) + 1);
  
  		},
  
  		easeInOutExpo: function(t) {
  
  			if (t === 0) {
  
  				return 0;
  
  			}
  
  			if (t === 1) {
  
  				return 1;
  
  			}
  
  			if ((t /= 1 / 2) < 1) {
  
  				return 1 / 2 * Math.pow(2, 10 * (t - 1));
  
  			}
  
  			return 1 / 2 * (-Math.pow(2, -10 * --t) + 2);
  
  		},
  
  		easeInCirc: function(t) {
  
  			if (t >= 1) {
  
  				return t;
  
  			}
  
  			return -1 * (Math.sqrt(1 - (t /= 1) * t) - 1);
  
  		},
  
  		easeOutCirc: function(t) {
  
  			return 1 * Math.sqrt(1 - (t = t / 1 - 1) * t);
  
  		},
  
  		easeInOutCirc: function(t) {
  
  			if ((t /= 1 / 2) < 1) {
  
  				return -1 / 2 * (Math.sqrt(1 - t * t) - 1);
  
  			}
  
  			return 1 / 2 * (Math.sqrt(1 - (t -= 2) * t) + 1);
  
  		},
  
  		easeInElastic: function(t) {
  
  			var s = 1.70158;
  
  			var p = 0;
  
  			var a = 1;
  
  			if (t === 0) {
  
  				return 0;
  
  			}
  
  			if ((t /= 1) === 1) {
  
  				return 1;
  
  			}
  
  			if (!p) {
  
  				p = 1 * 0.3;
  
  			}
  
  			if (a < Math.abs(1)) {
  
  				a = 1;
  
  				s = p / 4;
  
  			} else {
  
  				s = p / (2 * Math.PI) * Math.asin(1 / a);
  
  			}
  
  			return -(a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t * 1 - s) * (2 * Math.PI) / p));
  
  		},
  
  		easeOutElastic: function(t) {
  
  			var s = 1.70158;
  
  			var p = 0;
  
  			var a = 1;
  
  			if (t === 0) {
  
  				return 0;
  
  			}
  
  			if ((t /= 1) === 1) {
  
  				return 1;
  
  			}
  
  			if (!p) {
  
  				p = 1 * 0.3;
  
  			}
  
  			if (a < Math.abs(1)) {
  
  				a = 1;
  
  				s = p / 4;
  
  			} else {
  
  				s = p / (2 * Math.PI) * Math.asin(1 / a);
  
  			}
  
  			return a * Math.pow(2, -10 * t) * Math.sin((t * 1 - s) * (2 * Math.PI) / p) + 1;
  
  		},
  
  		easeInOutElastic: function(t) {
  
  			var s = 1.70158;
  
  			var p = 0;
  
  			var a = 1;
  
  			if (t === 0) {
  
  				return 0;
  
  			}
  
  			if ((t /= 1 / 2) === 2) {
  
  				return 1;
  
  			}
  
  			if (!p) {
  
  				p = 1 * (0.3 * 1.5);
  
  			}
  
  			if (a < Math.abs(1)) {
  
  				a = 1;
  
  				s = p / 4;
  
  			} else {
  
  				s = p / (2 * Math.PI) * Math.asin(1 / a);
  
  			}
  
  			if (t < 1) {
  
  				return -0.5 * (a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t * 1 - s) * (2 * Math.PI) / p));
  
  			}
  
  			return a * Math.pow(2, -10 * (t -= 1)) * Math.sin((t * 1 - s) * (2 * Math.PI) / p) * 0.5 + 1;
  
  		},
  
  		easeInBack: function(t) {
  
  			var s = 1.70158;
  
  			return 1 * (t /= 1) * t * ((s + 1) * t - s);
  
  		},
  
  		easeOutBack: function(t) {
  
  			var s = 1.70158;
  
  			return 1 * ((t = t / 1 - 1) * t * ((s + 1) * t + s) + 1);
  
  		},
  
  		easeInOutBack: function(t) {
  
  			var s = 1.70158;
  
  			if ((t /= 1 / 2) < 1) {
  
  				return 1 / 2 * (t * t * (((s *= (1.525)) + 1) * t - s));
  
  			}
  
  			return 1 / 2 * ((t -= 2) * t * (((s *= (1.525)) + 1) * t + s) + 2);
  
  		},
  
  		easeInBounce: function(t) {
  
  			return 1 - easingEffects.easeOutBounce(1 - t);
  
  		},
  
  		easeOutBounce: function(t) {
  
  			if ((t /= 1) < (1 / 2.75)) {
  
  				return 1 * (7.5625 * t * t);
  
  			} else if (t < (2 / 2.75)) {
  
  				return 1 * (7.5625 * (t -= (1.5 / 2.75)) * t + 0.75);
  
  			} else if (t < (2.5 / 2.75)) {
  
  				return 1 * (7.5625 * (t -= (2.25 / 2.75)) * t + 0.9375);
  
  			} else {
  
  				return 1 * (7.5625 * (t -= (2.625 / 2.75)) * t + 0.984375);
  
  			}
  
  		},
  
  		easeInOutBounce: function(t) {
  
  			if (t < 1 / 2) {
  
  				return easingEffects.easeInBounce(t * 2) * 0.5;
  
  			}
  
  			return easingEffects.easeOutBounce(t * 2 - 1) * 0.5 + 1 * 0.5;
  
  		}
  
  	};
  
  	//Request animation polyfill - http://www.paulirish.com/2011/requestanimationframe-for-smart-animating/
  
  	helpers.requestAnimFrame = (function() {
  
  		return window.requestAnimationFrame ||
  
  			window.webkitRequestAnimationFrame ||
  
  			window.mozRequestAnimationFrame ||
  
  			window.oRequestAnimationFrame ||
  
  			window.msRequestAnimationFrame ||
  
  			function(callback) {
  
  				return window.setTimeout(callback, 1000 / 60);
  
  			};
  
  	})();
  
  	helpers.cancelAnimFrame = (function() {
  
  		return window.cancelAnimationFrame ||
  
  			window.webkitCancelAnimationFrame ||
  
  			window.mozCancelAnimationFrame ||
  
  			window.oCancelAnimationFrame ||
  
  			window.msCancelAnimationFrame ||
  
  			function(callback) {
  
  				return window.clearTimeout(callback, 1000 / 60);
  
  			};
  
  	})();
  
  	//-- DOM methods
  
  	helpers.getRelativePosition = function(evt, chart) {
  
  		var mouseX, mouseY;
  
  		var e = evt.originalEvent || evt,
  
  			canvas = evt.currentTarget || evt.srcElement,
  
  			boundingRect = canvas.getBoundingClientRect();
  
  
  
  		if (e.touches && e.touches.length > 0) {
  
  			mouseX = e.touches[0].clientX;
  
  			mouseY = e.touches[0].clientY;
  
  
  
  		} else {
  
  			mouseX = e.clientX;
  
  			mouseY = e.clientY;
  
  		}
  
  
  
  		// Scale mouse coordinates into canvas coordinates
  
  		// by following the pattern laid out by 'jerryj' in the comments of
  
  		// http://www.html5canvastutorials.com/advanced/html5-canvas-mouse-coordinates/
  
  		var paddingLeft = parseFloat(helpers.getStyle(canvas, 'padding-left'));
  
  		var paddingTop = parseFloat(helpers.getStyle(canvas, 'padding-top'));
  
  		var paddingRight = parseFloat(helpers.getStyle(canvas, 'padding-right'));
  
  		var paddingBottom = parseFloat(helpers.getStyle(canvas, 'padding-bottom'));
  
  		var width = boundingRect.right - boundingRect.left - paddingLeft - paddingRight;
  
  		var height = boundingRect.bottom - boundingRect.top - paddingTop - paddingBottom;
  
  
  
  		// We divide by the current device pixel ratio, because the canvas is scaled up by that amount in each direction. However
  
  		// the backend model is in unscaled coordinates. Since we are going to deal with our model coordinates, we go back here
  
  		mouseX = Math.round((mouseX - boundingRect.left - paddingLeft) / (width) * canvas.width / chart.currentDevicePixelRatio);
  
  		mouseY = Math.round((mouseY - boundingRect.top - paddingTop) / (height) * canvas.height / chart.currentDevicePixelRatio);
  
  
  
  		return {
  
  			x: mouseX,
  
  			y: mouseY
  
  		};
  
  
  
  	};
  
  	helpers.addEvent = function(node, eventType, method) {
  
  		if (node.addEventListener) {
  
  			node.addEventListener(eventType, method);
  
  		} else if (node.attachEvent) {
  
  			node.attachEvent("on" + eventType, method);
  
  		} else {
  
  			node["on" + eventType] = method;
  
  		}
  
  	};
  
  	helpers.removeEvent = function(node, eventType, handler) {
  
  		if (node.removeEventListener) {
  
  			node.removeEventListener(eventType, handler, false);
  
  		} else if (node.detachEvent) {
  
  			node.detachEvent("on" + eventType, handler);
  
  		} else {
  
  			node["on" + eventType] = helpers.noop;
  
  		}
  
  	};
  
  	helpers.bindEvents = function(chartInstance, arrayOfEvents, handler) {
  
  		// Create the events object if it's not already present
  
  		if (!chartInstance.events)
  
  			chartInstance.events = {};
  
  
  
  		helpers.each(arrayOfEvents, function(eventName) {
  
  			chartInstance.events[eventName] = function() {
  
  				handler.apply(chartInstance, arguments);
  
  			};
  
  			helpers.addEvent(chartInstance.chart.canvas, eventName, chartInstance.events[eventName]);
  
  		});
  
  	};
  
  	helpers.unbindEvents = function(chartInstance, arrayOfEvents) {
  
  		helpers.each(arrayOfEvents, function(handler, eventName) {
  
  			helpers.removeEvent(chartInstance.chart.canvas, eventName, handler);
  
  		});
  
  	};
  
  
  
  	// Private helper function to convert max-width/max-height values that may be percentages into a number
  
  	function parseMaxStyle(styleValue, node, parentProperty) {
  
  		var valueInPixels;
  
  		if (typeof(styleValue) === 'string') {
  
  			valueInPixels = parseInt(styleValue, 10);
  
  
  
  			if (styleValue.indexOf('%') != -1) {
  
  				// percentage * size in dimension
  
  				valueInPixels = valueInPixels / 100 * node.parentNode[parentProperty];
  
  			}
  
  		} else {
  
  			valueInPixels = styleValue;
  
  		}
  
  
  
  		return valueInPixels;
  
  	}
  
  
  
  	// Private helper to get a constraint dimension
  
  	// @param domNode : the node to check the constraint on
  
  	// @param maxStyle : the style that defines the maximum for the direction we are using (max-width / max-height)
  
  	// @param percentageProperty : property of parent to use when calculating width as a percentage
  
  	function getConstraintDimension(domNode, maxStyle, percentageProperty) {
  
  		var constrainedDimension;
  
  		var constrainedNode = document.defaultView.getComputedStyle(domNode)[maxStyle];
  
  		var constrainedContainer = document.defaultView.getComputedStyle(domNode.parentNode)[maxStyle];
  
  		var hasCNode = constrainedNode !== null && constrainedNode !== "none";
  
  		var hasCContainer = constrainedContainer !== null && constrainedContainer !== "none";
  
  
  
  		if (hasCNode || hasCContainer) {
  
  			constrainedDimension = Math.min((hasCNode ? parseMaxStyle(constrainedNode, domNode, percentageProperty) : Number.POSITIVE_INFINITY), (hasCContainer ? parseMaxStyle(constrainedContainer, domNode.parentNode, percentageProperty) : Number.POSITIVE_INFINITY));
  
  		}
  
  		return constrainedDimension;
  
  	}
  
  	// returns Number or undefined if no constraint
  
  	helpers.getConstraintWidth = function(domNode) {
  
  		return getConstraintDimension(domNode, 'max-width', 'clientWidth');
  
  	};
  
  	// returns Number or undefined if no constraint
  
  	helpers.getConstraintHeight = function(domNode) {
  
  		return getConstraintDimension(domNode, 'max-height', 'clientHeight');
  
  	};
  
  	helpers.getMaximumWidth = function(domNode) {
  
  		var container = domNode.parentNode;
  
  		var padding = parseInt(helpers.getStyle(container, 'padding-left')) + parseInt(helpers.getStyle(container, 'padding-right'));
  
  
  
  		var w = container.clientWidth - padding;
  
  		var cw = helpers.getConstraintWidth(domNode);
  
  		if (cw !== undefined) {
  
  			w = Math.min(w, cw);
  
  		}
  
  
  
  		return w;
  
  	};
  
  	helpers.getMaximumHeight = function(domNode) {
  
  		var container = domNode.parentNode;
  
  		var padding = parseInt(helpers.getStyle(container, 'padding-top')) + parseInt(helpers.getStyle(container, 'padding-bottom'));
  
  
  
  		var h = container.clientHeight - padding;
  
  		var ch = helpers.getConstraintHeight(domNode);
  
  		if (ch !== undefined) {
  
  			h = Math.min(h, ch);
  
  		}
  
  
  
  		return h;
  
  	};
  
  	helpers.getStyle = function(el, property) {
  
  		return el.currentStyle ?
  
  			el.currentStyle[property] :
  
  			document.defaultView.getComputedStyle(el, null).getPropertyValue(property);
  
  	};
  
  	helpers.retinaScale = function(chart) {
  
  		var ctx = chart.ctx;
  
  		var width = chart.canvas.width;
  
  		var height = chart.canvas.height;
  
  		var pixelRatio = chart.currentDevicePixelRatio = window.devicePixelRatio || 1;
  
  
  
  		if (pixelRatio !== 1) {
  
  			ctx.canvas.height = height * pixelRatio;
  
  			ctx.canvas.width = width * pixelRatio;
  
  			ctx.scale(pixelRatio, pixelRatio);
  
  
  
  			// Store the device pixel ratio so that we can go backwards in `destroy`.
  
  			// The devicePixelRatio changes with zoom, so there are no guarantees that it is the same
  
  			// when destroy is called
  
  			chart.originalDevicePixelRatio = chart.originalDevicePixelRatio || pixelRatio;
  
  		}
  
  
  
  		ctx.canvas.style.width = width + 'px';
  
  		ctx.canvas.style.height = height + 'px';
  
  	};
  
  	//-- Canvas methods
  
  	helpers.clear = function(chart) {
  
  		chart.ctx.clearRect(0, 0, chart.width, chart.height);
  
  	};
  
  	helpers.fontString = function(pixelSize, fontStyle, fontFamily) {
  
  		return fontStyle + " " + pixelSize + "px " + fontFamily;
  
  	};
  
  	helpers.longestText = function(ctx, font, arrayOfStrings, cache) {
  
  		cache = cache || {};
  
  		cache.data = cache.data || {};
  
  		cache.garbageCollect = cache.garbageCollect || [];
  
  
  
  		if (cache.font !== font) {
  
  			cache.data = {};
  
  			cache.garbageCollect = [];
  
  			cache.font = font;
  
  		}
  
  
  
  		ctx.font = font;
  
  		var longest = 0;
  
  		helpers.each(arrayOfStrings, function(string) {
  
  			// Undefined strings should not be measured
  
  			if (string !== undefined && string !== null) {
  
  				var textWidth = cache.data[string];
  
  				if (!textWidth) {
  
  					textWidth = cache.data[string] = ctx.measureText(string).width;
  
  					cache.garbageCollect.push(string);
  
  				}
  
  
  
  				if (textWidth > longest) {
  
  					longest = textWidth;
  
  				}
  
  			}
  
  		});
  
  
  
  		var gcLen = cache.garbageCollect.length / 2;
  
  		if (gcLen > arrayOfStrings.length) {
  
  			for (var i = 0; i < gcLen; i++) {
  
  				delete cache.data[cache.garbageCollect[i]];
  
  			}
  
  			cache.garbageCollect.splice(0, gcLen);
  
  		}
  
  
  
  		return longest;
  
  	};
  
  	helpers.drawRoundedRectangle = function(ctx, x, y, width, height, radius) {
  
  		ctx.beginPath();
  
  		ctx.moveTo(x + radius, y);
  
  		ctx.lineTo(x + width - radius, y);
  
  		ctx.quadraticCurveTo(x + width, y, x + width, y + radius);
  
  		ctx.lineTo(x + width, y + height - radius);
  
  		ctx.quadraticCurveTo(x + width, y + height, x + width - radius, y + height);
  
  		ctx.lineTo(x + radius, y + height);
  
  		ctx.quadraticCurveTo(x, y + height, x, y + height - radius);
  
  		ctx.lineTo(x, y + radius);
  
  		ctx.quadraticCurveTo(x, y, x + radius, y);
  
  		ctx.closePath();
  
  	};
  
  	helpers.color = function(c) {
  
  		if (!color) {
  
  			console.log('Color.js not found!');
  
  			return c;
  
  		}
  
  
  
  		/* global CanvasGradient */
  
  		if (c instanceof CanvasGradient) {
  
  			return color(Chart.defaults.global.defaultColor);
  
  		}
  
  
  
  		return color(c);
  
  	};
  
  	helpers.addResizeListener = function(node, callback) {
  
  		// Hide an iframe before the node
  
  		var hiddenIframe = document.createElement('iframe');
  
  		var hiddenIframeClass = 'chartjs-hidden-iframe';
  
  
  
  		if (hiddenIframe.classlist) {
  
  			// can use classlist
  
  			hiddenIframe.classlist.add(hiddenIframeClass);
  
  		} else {
  
  			hiddenIframe.setAttribute('class', hiddenIframeClass);
  
  		}
  
  
  
  		// Set the style
  
  		hiddenIframe.style.width = '100%';
  
  		hiddenIframe.style.display = 'block';
  
  		hiddenIframe.style.border = 0;
  
  		hiddenIframe.style.height = 0;
  
  		hiddenIframe.style.margin = 0;
  
  		hiddenIframe.style.position = 'absolute';
  
  		hiddenIframe.style.left = 0;
  
  		hiddenIframe.style.right = 0;
  
  		hiddenIframe.style.top = 0;
  
  		hiddenIframe.style.bottom = 0;
  
  
  
  		// Insert the iframe so that contentWindow is available
  
  		node.insertBefore(hiddenIframe, node.firstChild);
  
  
  
  		(hiddenIframe.contentWindow || hiddenIframe).onresize = function() {
  
  			if (callback) {
  
  				callback();
  
  			}
  
  		};
  
  	};
  
  	helpers.removeResizeListener = function(node) {
  
  		var hiddenIframe = node.querySelector('.chartjs-hidden-iframe');
  
  
  
  		// Remove the resize detect iframe
  
  		if (hiddenIframe) {
  
  			hiddenIframe.parentNode.removeChild(hiddenIframe);
  
  		}
  
  	};
  
  	helpers.isArray = function(obj) {
  
  		if (!Array.isArray) {
  
  			return Object.prototype.toString.call(obj) === '[object Array]';
  
  		}
  
  		return Array.isArray(obj);
  
  	};
  
  	helpers.pushAllIfDefined = function(element, array) {
  
  		if (typeof element === "undefined") {
  
  			return;
  
  		}
  
  
  
  		if (helpers.isArray(element)) {
  
  			array.push.apply(array, element);
  
  		} else {
  
  			array.push(element);
  
  		}
  
  	};
  
  	helpers.callCallback = function(fn, args, _tArg) {
  
  		if (fn && typeof fn.call === 'function') {
  
  			fn.apply(_tArg, args);
  
  		}
  
  	};
  
  
  
  };
  
  