Perlin Outlines

perlin outlines
move your mouse around
http://actionsnippet.com/?p=1878

by shapevent 08 Aug 2009

Tags

BitmapData BitmapData, BlendMode, Noise Perlin filter filters, setVector,
Embed

/**
 * Copyright shapevent ( http://wonderfl.net/user/shapevent )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/Ab5p
 */

package {

        // perlin outlines
        // move your mouse around
        // http://actionsnippet.com/?p=1878 
	import flash.display.*;
	import flash.geom.*;
	import flash.events.*;
        import flash.filters.*;


	[SWF(width = 600, height=600, backgroundColor=0xCCCCCC, frameRate=24)]

       public class PerlinOutlines extends MovieClip {
		private var canvas:BitmapData;
		private var blur:BitmapData;
		private var w:int;
		private var hw:int;
		private var size:int;
		private var seed:Number;
		private var pnt:Point;
		private var dy:Number;
		private var dx:Number;
		private var blr:BlurFilter;


               public function PerlinOutlines(){
                  // init
			canvas = new BitmapData(stage.stageWidth,stage.stageHeight, false, 0x000000);
			blur = new BitmapData(stage.stageWidth,stage.stageHeight, false, 0x000000);
			addChild(new Bitmap(canvas, "auto", true));
			w = canvas.width
			hw = w / 2;
			size = w * w;
			seed = Math.random()*100;
			pnt = new Point();
			dy = 0, dx = 0;
			blr = new BlurFilter(10,10,1);
			addEventListener(Event.ENTER_FRAME, onLoop);
			

               }
               // private methods

		private function onLoop(evt:Event):void {
			dx += (mouseX - dx) / 4;
			dy += (mouseY - dy) / 4;
			canvas.lock();
			canvas.perlinNoise(hw,hw,2,seed,false, false, 1, true, [new Point(dx, dy), new Point(-dx, -dy)]);
			var pix:Vector.<uint> = canvas.getVector(canvas.rect);
			for (var i:int = 0; i<size; i++){
				var col:uint = 255 - pix[i] <<4 & 0x00FF00;
				pix[i] = col <<8 | col | col>> 8;
			}
			canvas.setVector(canvas.rect, pix);
			blur.copyPixels(canvas, canvas.rect, pnt);
			blur.applyFilter(blur, blur.rect, pnt, blr);
			canvas.draw(blur, null, null, BlendMode.DIFFERENCE);
			canvas.draw(canvas, null, null, BlendMode.INVERT);
			canvas.unlock();
		}
		

       }

}