anchor.diff:      return frame;
     }
   
  +  @override
     void setNext(KeyFrame frame) {
       // Do nothing.
     }
   
  +  @override
     void applyInterpolation(
         ActorComponent component, double time, KeyFrame toFrame, double mix) {
       ActorPath path = component as ActorPath;
  
positive.code:     return frame;
    }
  
    void setNext(KeyFrame frame) {
      // Do nothing.
    }
  
    void applyInterpolation(
        ActorComponent component, double time, KeyFrame toFrame, double mix) {
      ActorColor ac = component as ActorColor;
  
negative.code:     int l = _vertices.length;
  
      double f = (time - _time) / (toFrame.time - _time);
      if(_interpolator != null) {
        f = _interpolator.getEasedMix(f);
      }
      double fi = 1.0 - f;
      if (mix == 1.0) {
        for (int i = 0; i < l; i++) {
  