forked from: forked from: 20,000 particles with BetweenAS3

by timmymayes 19 Feb 2012

• Forked from NaokiHada's forked from: 20,000 particles with BetweenAS3
• Diff: 4
• Related works: 6
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// forked from NaokiHada's forked from: 20,000 particles with BetweenAS3
// forked from beinteractive's 20,000 particles with BetweenAS3
package
{
    import com.flashdynamix.utils.SWFProfiler;
    import flash.display.Bitmap;
    import flash.display.BitmapData;
    import flash.display.PixelSnapping;
    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageQuality;
    import flash.display.StageScaleMode;
    import flash.events.Event;
    import flash.geom.ColorTransform;
    import flash.geom.Point;
    import org.libspark.betweenas3.BetweenAS3;
    import org.libspark.betweenas3.easing.Back;
    import org.libspark.betweenas3.easing.Quart;
    import org.libspark.betweenas3.tweens.ITween;
    
    public class ParticleBetween extends Sprite
    {
        private static const NUM_PARTICLES:uint = 2000;
        //private static const NUM_PARTICLES:uint = 20;
        private static const FADE:ColorTransform = new ColorTransform(1, 1, 1, 1, -32, -16, -16);
        
        public function ParticleBetween()
        {
            setupParticles();
            setupScreen();
            setupStage();
            
            SWFProfiler.init(this);
            
            addEventListener(Event.ENTER_FRAME, enterFrameHandler);
        }
        
        private var _bitmapData:BitmapData;
        private var _bitmap:Bitmap;
        private var _particles:Particle;
        
        private function setupParticles():void
        {
            var prev:Particle = _particles = new Particle();
            var p:Particle = null;
            var a:Number, dx:Number, dy:Number;
            var t:ITween;
            var i:int = NUM_PARTICLES;
            while (--i >= 0) {
                
                a = Math.random() * Math.PI * 2;
                dx = Math.cos(a) * 465 + 465 / 2;
                dy = Math.sin(a) * 465 + 465 / 2;
                
                p = new Particle();
                p.p.x = 465 / 2;
                p.p.y = 465 / 2;
                
                t = BetweenAS3.tween(p.p, {x: dx, y: dy}, null, 1.5 + Math.random() * 4.5, Quart.easeIn);
                t.stopOnComplete = false;
                t.play();
                
                prev.next = p;
                prev = p;
            }
        }
        
        private function setupScreen():void
        {
            _bitmapData = new BitmapData(465, 465, false, 0x000000);
            _bitmap = addChild(new Bitmap(_bitmapData, PixelSnapping.NEVER, false)) as Bitmap;
        }
        
        private function setupStage():void
        {
            stage.frameRate = 60;
            stage.quality = StageQuality.BEST;
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;
            stage.addEventListener(Event.RESIZE, resizeHandler);
            resizeHandler(null);
        }
        
        private function resizeHandler(e:Event):void
        {
            _bitmap.x = Math.floor((stage.stageWidth - 465) / 2);
            _bitmap.y = Math.floor((stage.stageHeight - 465) / 2);
        }
        
        private function enterFrameHandler(e:Event):void
        {
            var bitmapData:BitmapData = _bitmapData;
            
            bitmapData.lock();
            bitmapData.colorTransform(_bitmapData.rect, FADE);
            
            var p:Particle = _particles;
            var pos:Point;
            while ((p = p.next) != null) {
                pos = p.p;
                bitmapData.setPixel(pos.x >> 0, pos.y >> 0, 0xffffff);                
            }
            
            bitmapData.unlock();
        }
    }
}

import flash.geom.Point;

internal class Particle
{
    public var p:Point = new Point();
    public var next:Particle;
}