g_animRate = 60.0;
g_animFrameLen = 1.0 / g_animRate;

AnimExecuter = Class.create(PeriodicalExecuter, {
  initialize: function($super, callback, duration) {
	$super(callback, g_animFrameLen);
	this.animPos = 0;
	this.setDuration(duration);
  },
	
  itersFromSecs: function(s) {
	return s * g_animRate;
  },

  setDuration: function(s) {
	this.iterCount = s * g_animRate;
  },

  incrementAnim: function() {
	this.animPos++;
	if (this.animPos > this.iterCount) {
		this.stop();
		return false;
	} else
		return true;
  },

  animPosition: function() {
	return (this.animPos/this.iterCount);
  }
});