Merge remote-tracking branch 'origin/animation-refactory' into animation-refactory

Conflicts:
	src/Chart.Core.js

diff --cc src/Chart.Core.js
index 6635e1bd837ca725fba12cb16f714d0224d7bc8c,565ceeeb1da8d2fc6c0deca336d2c7dda3c7cd62..2c1229d157d349c130ffc66b65c1e522e9bc8a8b
--- 1/src/Chart.Core.js
--- 2/src/Chart.Core.js
+++ b/src/Chart.Core.js
@@@ -2075,12 -2075,10 +2075,12 @@@
        });
  
        Chart.animationService = {
 +              frameDuration: 17,
                animations: [],
-               addAnimation: function(chart, animationObject) {
 +              dropFrames: 0,
+               addAnimation: function(chartInstance, animationObject) {
                        for (var index = 0; index < this.animations.length; ++ index){
-                               if (this.animations[index].chart === chart){
+                               if (this.animations[index].chartInstance === chartInstance){
                                        // replacing an in progress animation
                                        this.animations[index].lastTimeRun = null;
                                        this.animations[index].animationObject = animationObject;
@@@ -2095,20 -2093,27 +2095,35 @@@
                        });
  
                        // If there are no animations queued, manually kickstart a digest, for lack of a better word
-                       if(!this.animations.length){
-                               helpers.requestAnimFrame(this.startDigest);
+                       if (this.animations.length) {
+                               helpers.requestAnimFrame.call(window, this.digestWrapper);
                        }
                },
+               // Cancel the animation for a given chart instance
+               cancelAnimation: function(chartInstance) {
+                       var index = helpers.findNextWhere(this.animations, function(animationWrapper) {
+                               return animationWrapper.chartInstance === chartInstance;
+                       });
+                       
+                       if (index != -1)
+                       {
+                               this.animations.splice(index, 1);
+                       }
+               },
+               // calls startDigest with the proper context
+               digestWrapper: function() {
+                       Chart.animationService.startDigest.call(Chart.animationService);
+               },
                startDigest: function() {
  
 +                      var startTime = Date.now();
 +                      var framesToDrop = 0;
 +
 +                      if(this.dropFrames > 1){
 +                              framesToDrop = Math.floor(this.dropFrames);
 +                              this.dropFrames -= framesToDrop;
 +                      }
 +
                        for (var i = 0; i < this.animations.length; i++) {
  
                                var currentAnimation = this.animations[i];
@@@ -2116,10 -2121,10 +2131,10 @@@
                                if (currentAnimation.animationObject.currentStep === null){
                                        currentAnimation.animationObject.currentStep = 0;
                                } else {
 -                                      currentAnimation.animationObject.currentStep++;
 +                                      currentAnimation.animationObject.currentStep += 1 + framesToDrop;
                                }
                                
-                               currentAnimation.animationObject.render(currentAnimation.animationObject);
+                               currentAnimation.animationObject.render(currentAnimation.chartInstance, currentAnimation.animationObject);
                                
                                if (currentAnimation.animationObject.currentStep == currentAnimation.animationObject.numSteps){
                                        // executed the last frame. Remove the animation.
@@@ -2129,17 -2134,9 +2144,17 @@@
                                }
                        }
  
 +                      var endTime = Date.now();
 +                      var delay = endTime - startTime - this.frameDuration;
 +                      var frameDelay = delay / this.frameDuration;
 +
 +                      if(frameDelay > 1){
 +                              this.dropFrames += frameDelay;
 +                      }
 +
                        // Do we have more stuff to animate?
                        if (this.animations.length > 0){
-                               requestAnimationFrame(this.startDigest);
+                               helpers.requestAnimFrame.call(window, this.digestWrapper);
                        }
                }
        };