my own bubble simulator

by wh0 05 May 2010

Tags

bubbles
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// forked from wh0's particle bullet linked
// forked from wh0's particle bullet
package {
	import flash.display.Sprite;
	import flash.display.StageScaleMode;
	import flash.display.StageAlign;
	import flash.events.Event;
	public class Bubbles extends Sprite {
		
		private const head:Particle = new Particle();
		
		public function Bubbles() {
			stage.align = StageAlign.TOP_LEFT;
			stage.scaleMode = StageScaleMode.NO_SCALE;
			Particle.init(stage);
			addEventListener(Event.ENTER_FRAME, step);
		}

		private function step(e:Event):void {
			graphics.clear();
			var prev:Particle = head;
			for (var p:Particle = head.next; p; p = p.next) {
				if (p.draw(graphics))
					prev.next = p.next;
				else
					prev = prev.next;
			}
			head.next = new Particle(Math.random() * stage.stageWidth, stage.stageHeight + 32, head.next);
		}
		
	}
}

import flash.display.BitmapData;
import flash.display.Graphics;
import flash.display.Stage;
import flash.utils.getTimer;
class Particle {
	
	internal static var ken:BitmapData;
	
	public static function init(stage:Stage):void {
		ken = new BitmapData(stage.stageWidth / 8, stage.stageHeight / 8, false, 0x000000);
		ken.perlinNoise(8, 8, 2, getTimer(), false, true);
	}
	
	private var px:Number, py:Number, pz:Number, vx:Number;
	internal var next:Particle;
	
	public function Particle(x:int = 0, y:int = 0, n:Particle = null) {
		px = x;
		py = y;
		pz = Math.random() * 3 + 1;
		vx = Math.random() - 0.5;
		next = n;
	}
	
	public function draw(g:Graphics):Boolean {
		g.lineStyle(0, 0x000000, 1 / pz);
		g.drawCircle(px, py, 16 / pz / (1 + py / 800));
		if (px >= 0 && px < ken.width * 8 && py >= 0 && py < ken.height * 8) {
			var k:uint = ken.getPixel(px / 8, py / 8);
			if (pz < 2)
				vx += ((k & 0xff) - 128) / 1024.;
			else if (pz < 4)
				vx += ((k >> 8 & 0xff) - 128) / 1024.;
			else
				vx += ((k >> 16) - 128) / 1024.;
		}
		vx *= 0.95;
		px += vx / pz;
		py -= 4 / pz;
		return py < -32;
	}
	
}