flash on 2011-2-17

/**
 * Copyright yama3 ( http://wonderfl.net/user/yama3 )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/fyGI
 */

package {
    import flash.display.Bitmap;
    import flash.display.BitmapData;
    import flash.display.PixelSnapping;
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.events.MouseEvent;
    import flash.geom.Rectangle;
    
    [SWF(width="465", height="465", backgroundColor="0xffffff", frameRate="60")]
    
    public class FlashTest extends Sprite {
        private const WIDTH:Number = 465;
        private const HEIGH:Number = 465;
        
        private var _canvas:BitmapData;
        private var _fast:Particle;
        
        
        public function FlashTest() {
            init();            
        }
        
        private function init():void
        {
            _canvas = new BitmapData(WIDTH, HEIGH, true, 0x99ffffff);
            addChild(new Bitmap(_canvas)) as Bitmap;
            
            stage.addEventListener(Event.ENTER_FRAME, enterframeHandler);
            stage.addEventListener(MouseEvent.CLICK, onClick);
            
            _fast = new Particle();
            var p:Particle = _fast;
            for(var i:uint=0; i < 10000; i++) {
                if(i > 0) {
                    p.next = new Particle();
                    p = p.next;
                }
                initParticle(p);
            }
        }
        
        private function onClick(e:MouseEvent):void
        {
            _canvas.fillRect(new Rectangle(0,0,WIDTH,HEIGH),0xffffffff);
            var p:Particle = _fast;
            while(p) {
                initParticle(p);
                p = p.next;
            }
        }
        
        private function initParticle(p:Particle):void
        {
            p.x = Math.random() * WIDTH * 2 - WIDTH / 2;
            p.y = Math.random() * HEIGH * 2 - HEIGH / 2;
            p.cnt = 0;
            p.r = Math.random() * 0x1f + 0xE0;
            p.g = Math.random() * 0xff;
            p.b = Math.random() * 0x66 + 0x99;
            p.c = 0x99 << 24 | p.r << 16 | p.g << 8 | p.b;
        }
        
        private function enterframeHandler(e:Event):void
        {
            update();
        }
        
        private function update():void {
            _canvas.lock();
            var p:Particle = _fast;
            while(p) {
                if(p.next && p.cnt < 1000) {
                    p.x = p.x + (p.next.x - p.x) / 10;
                    p.y = p.y + (p.next.y - p.y) / 10;
                    if(Math.floor(p.cnt / 100) % 2 == 0) {
                        p.c = 0x99 << 24 | p.r << 16 | p.g - (p.next.x - p.x) / 4 << 8 | p.b - (p.next.y - p.y)/4;
                    }else {
                        p.c += (0x9999ffff - p.c) / 2;
                    }
                } else {
                    if(p.next) {
                        p.x = p.x + (p.next.x - p.x) / 10;
                        p.y = p.y + (p.next.y - p.y) / 10;
                        if(Math.floor(p.cnt / 100) % 2 == 0) {
                            p.c = 0x99 << 24 | p.r << 16 | p.g - (p.next.x - p.x)/4 << 8 | p.b - (p.next.y - p.y)/4;
                        } else {
                            p.c += (0x9999ffff - p.c) / 2;
                        }
                    }
                    p.c += (0x9999ffff - p.c) / 2;
                    p.x = p.x + ((WIDTH/2) - p.x) / 1000;
                    p.y = p.y + ((HEIGH/2) - p.y) / 1000;
                }
                _canvas.setPixel32(p.x, p.y, p.c);
                p.cnt++;
                p = p.next;
            }
            _canvas.unlock();
        }
    }
}

class Particle
{
    public var x:Number;
    public var y:Number;
    public var vx:Number;
    public var vy:Number;
    public var c:uint;
    public var r:uint;
    public var g:uint;
    public var b:uint;
    public var next:Particle;
    public var cnt:Number;
    
    private const WIDTH:Number = 465;
    private const HEIGH:Number = 465;
    
    public function Particle()
    {
        this.vx = 0;
        this.vy = 0;
        this.cnt = 0;
    }
}