Flash / Flex / ActionScript/Animation/Animation Utilities

Simple Stage framrate measuring class

   <source lang="java">

/*

* hexagon framework - Multi-Purpose ActionScript 3 Framework.
* Copyright (C) 2007 Hexagon Star Softworks
*       __    __
*    __/  \__/  \__    __
*   /  \__/HEXAGON \__/  \
*   \__/  \__/ FRAMEWORK_/
*            \__/  \__/
*
* ``The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
* License for the specific language governing rights and limitations
* under the License.
*/

package com.hexagonstar.util.debug {

 import flash.display.Stage;
 import flash.events.Event;
 import flash.events.EventDispatcher;
 import flash.events.TimerEvent;
 import flash.utils.Timer;
 
 /**
  * Simple Stage framrate measuring class.
  */
 public class FPSMeter extends EventDispatcher
 {
   // Properties /////////////////////////////////////////////////////////////////
   
   public static const FPS_UPDATE:String = "fpsUpdate";
   
   private var _stage:Stage;
   private var _timer:Timer;
   private var _fps:int;
   private var _isRunning:Boolean;
   
   // Constructor ////////////////////////////////////////////////////////////////
   
   /**
    * Constructor
    */
   public function FPSMeter(stage:Stage)
   {
     _stage = stage;
     _fps = 0;
     _isRunning = false;
   }
   
   // Public Methods /////////////////////////////////////////////////////////////
   
   /**
    * Starts FPS polling.
    */
   public function start(pollInterval:uint = 1000):void
   {
     if (!_isRunning)
     {
       _isRunning = true;
       _timer = new Timer(pollInterval, 0);
       _timer.addEventListener(TimerEvent.TIMER, onTimer);
       _stage.addEventListener(Event.ENTER_FRAME, onEnterFrame);
       _timer.start();
     }
   }
   
   /**
    * Stops FPS polling.
    */
   public function stop():void
   {
     if (_isRunning)
     {
       _isRunning = false;
       _timer.stop();
       _timer.removeEventListener(TimerEvent.TIMER, onTimer);
       _stage.removeEventListener(Event.ENTER_FRAME, onEnterFrame);
       _timer = null;
     }
   }
   
   /**
    * Returns the current FPS.
    * 
    * @return The currently polled frames per second.
    */
   public function getFPS():int
   {
     return _fps;
   }
   
   // Private Methods ////////////////////////////////////////////////////////////
   
   /**
    * Called on every Timer event.
    * @private
    */
   private function onTimer(event:TimerEvent):void
   {
     dispatchEvent(new Event(FPSMeter.FPS_UPDATE));
     _fps = 0;
   }
   
   /**
    * Called on every EnterFrame event.
    * @private
    */
   private function onEnterFrame(event:Event):void
   {
     _fps++;
   }
 }

}

       </source>