text: /*
   * Copyright 2009, Google Inc.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are
   * met:
   *
   *     * Redistributions of source code must retain the above copyright
   * notice, this list of conditions and the following disclaimer.
   *     * Redistributions in binary form must reproduce the above
   * copyright notice, this list of conditions and the following disclaimer
   * in the documentation and/or other materials provided with the
   * distribution.
   *     * Neither the name of Google Inc. nor the names of its
   * contributors may be used to endorse or promote products derived from
   * this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  
  /**
   * The Orbit tool allows the user to look around the model by click-dragging.
   * The shift key enters a pan mode instead of orbiting.
   */
  function OrbitTool(camera) {
    this.camera = camera;
    this.lastOffset = null;
    this.mouseLeftDown = false;
    this.mouseMiddleDown = false;
  }
  
  OrbitTool.prototype.handleMouseDown = function(e) {
    this.lastOffset = { x: e.x, y: e.y };
    if (e.button == g_o3d.Event.BUTTON_LEFT) {
      this.mouseLeftDown = true;
    } else if (e.button == g_o3d.Event.BUTTON_MIDDLE) {
      this.mouseMiddleDown = true;
    }
  };
  
  OrbitTool.prototype.handleMouseMove = function(e) {
    if (e.x !== undefined && (this.mouseLeftDown || this.mouseMiddleDown)) {
      var offset = { x: e.x, y: e.y };
  
      dY = (offset.y - this.lastOffset.y);
      dX = (offset.x - this.lastOffset.x);
      this.lastOffset = offset;
      panInsteadOfOrbit = (this.mouseLeftDown && this.mouseMiddleDown) ||
          e.shiftKey;
      if (panInsteadOfOrbit) {
        dX *= -1;
        this.camera.target.x -= (dY * Math.cos(this.camera.eye.rotZ) +
            dX * Math.sin(this.camera.eye.rotZ)) /
            (700 / this.camera.eye.distanceFromTarget);
        this.camera.target.y += (-dY * Math.sin(this.camera.eye.rotZ) +
            dX * Math.cos(this.camera.eye.rotZ)) /
            (700 / this.camera.eye.distanceFromTarget);
      } else {
        this.camera.eye.rotZ -= dX / 300;
        this.camera.eye.rotH -= dY / 300;
        this.camera.eye.rotH = peg(this.camera.eye.rotH, 0.1, Math.PI - 0.1);
        document.getElementById('output').innerHTML = this.camera.eye.rotH;
      }
      this.camera.update();
    }
  };
  
  OrbitTool.prototype.handleMouseUp = function(e) {
    if (e.button == g_o3d.Event.BUTTON_LEFT) {
      this.mouseLeftDown = false;
    } else if (e.button == g_o3d.Event.BUTTON_MIDDLE) {
      this.mouseMiddleDown = false;
    }
  };
  
  OrbitTool.prototype.handleKeyDown = function(e) {
    return false;
  };
  
  OrbitTool.prototype.handleKeyUp = function(e) {
    return false;
  };
  