/**
 * Clifford Attractor
 * refer to http://local.wasp.uwa.edu.au/~pbourke/fractals/clifford/
 * ...
 * @author sph62
 * 
 */
package {
	import flash.display.Bitmap;
	import flash.display.BitmapData;
	import flash.display.Sprite;
	import flash.display.Stage;
	import flash.events.Event;
	import flash.events.MouseEvent;
	import flash.text.TextField;
	
	[SWF(backgroundColor="0x000000", frameRate="60")]
	public class Attractor extends Sprite {
		
		private const PARTICLES_NUM:int = 200;
		private const RANGE:Number = 2.5;
		
		private var canvas:Bitmap;
		
		private var params:Vector.<Number>;
		private var particleList:Vector.<Particle> = new Vector.<Particle>;
		
		public function Attractor():void {
			if (stage) init();
			else addEventListener(Event.ADDED_TO_STAGE, init);
		}
		
		private function init(e:* = null):void {
			removeEventListener(Event.ADDED_TO_STAGE, init);
			
			var info:TextField = new TextField();
			info.textColor = 0x999999;
			info.autoSize = "left";
			info.appendText("だんだんできてきますよー \nClick to Reset");
			addChild(info);
			
			setParams();
			setParticles();
			setCanvas();
			addEventListener(Event.ENTER_FRAME, draw);
			stage.addEventListener(MouseEvent.CLICK, reset)
		}
		
		private function reset(e:MouseEvent):void {
			setParams();
			setParticles();
			canvas.bitmapData.dispose();
			var canvasData:BitmapData = new BitmapData(stage.stageWidth, stage.stageHeight, false, 0x00000000);
			canvas.bitmapData = canvasData;
		}
		
		private function draw(e:Event):void {
			var i:int;
			var c:uint, r:uint, g:uint, b:uint;
        		canvas.bitmapData.lock();
			for (i = 0 ; i < PARTICLES_NUM; i++) {
				particleList[i].update();
				c = canvas.bitmapData.getPixel(particleList[i].pos.x, particleList[i].pos.y);
				if((c & 0xFF) < 0xFF){
					r = (((c >> 16) & 0xFF) + 0x05*Math.random());
					g = (((c >> 8) & 0xFF) + 0x10*Math.random());
					b = ((c & 0xFF) + 0x25*Math.random());
					c =  (r << 16) | (g << 8) | b;
					canvas.bitmapData.setPixel(particleList[i].pos.x, particleList[i].pos.y, c);
				}
			}
			canvas.bitmapData.unlock();
		}
		
		private function setCanvas():void{
			var canvasData:BitmapData = new BitmapData(stage.stageWidth, stage.stageHeight, false, 0x00000000);
			canvas = new Bitmap(canvasData);
			addChildAt(canvas,0);
		}
		
		private function setParticles():void {
			var i:int;
			for (i = 0 ; i < PARTICLES_NUM; i++) {
				particleList[i] = new Particle(params,stage.stageWidth,stage.stageHeight);
			}
		}
		
		private function setParams():void {
			params = new Vector.<Number>(4,true);
			params[0] = Math.random() * RANGE + 1;
			params[1] = Math.random() * RANGE + 1;
			params[2] = Math.random() * RANGE + 1;
			params[3] = Math.random() * RANGE + 1;
		}
		
	}
	
}
import flash.geom.Point;

class Particle {
	private var nx:Number;
	private var ny:Number;
	private var ox:Number;
	private var oy:Number;
	private var _pos:Point;
	private var _params:Vector.<Number>;
	private var _stageWidth:int;
	private var _stageHeight:int;
	
	public function Particle(params:Vector.<Number> , stageWidth:int,stageHeight:int) {
		_params = params;
		_stageWidth = stageWidth;
		_stageHeight = stageHeight;
		_pos = new Point();
		
		ox = Math.random() * - 0.5
		oy = Math.random() * - 0.5
	}
	
	public function update():void {
		nx = Math.sin(_params[0] * oy) - Math.cos(_params[1] * ox);
		ny = Math.sin(_params[2] * ox) - Math.cos(_params[3] * oy);
		ox = nx;
		oy = ny;
		_pos.x = _stageWidth/4 * nx + _stageWidth/2;
		_pos.y = _stageHeight/4 * ny + _stageHeight/2;
	}
	
	public function get pos():Point { return _pos; }
}