forked from: Unknown Pleasures

by masika 22 Dec 2008

Embed

// forked from borealkiss's Unknown Pleasures
package {
	import flash.display.DisplayObjectContainer;
	import flash.display.Sprite;
	import flash.display.Shape;
	import flash.display.Graphics;
	import flash.display.BitmapData;
	import flash.events.MouseEvent;
	[SWF(width="600",height="600",backgroundColor="0x0")]

	public class Fl025_The25Line extends Sprite{
		private var _bitmapData:BitmapData = new BitmapData(600,100,false,0x0);
		private var _yCrossSection:Number = Math.random()*100;
		
		public function Fl025_The25Line(){
			var container:Sprite = new Sprite()
			this.addChild(container);
			for (var i:int=0; i<60; i++){
				_bitmapData.perlinNoise(600/5,100/5,5,Math.floor(10*Math.random()+1),true,false,7,true);
				var shape:Shape = new Shape();
				this.draw(shape.graphics,_bitmapData);
				container.addChild(shape);
				shape.y = 600*i/60 + 100;//Tune
			}
			container.scaleX = 0.2;
                        container.scaleY = 0.25
			container.x = container.y = 600/2 - container.width/2;
			this.addMask(container);
		}
		
		protected function draw(g:Graphics,sourceBitmapData:BitmapData):void{
			g.lineStyle(0,0xbbbbbb);
			//var y:int = _yCrossSection;
			var y:int = 37;
			g.beginFill(0x0);
			g.moveTo(0,0)
			for (var x:int=0; x<sourceBitmapData.width; x++) g.lineTo( x,-1*getHeight(x,y,sourceBitmapData) );
			g.lineTo(x,0);
			g.endFill();
		}
		
		protected function addMask(target:DisplayObjectContainer):void{
			var margin:Number = 5;//Tune
			var mask:Sprite = new Sprite();
			this.addChild(mask);
			mask.graphics.beginFill(0x00FFFF,0.5);
			mask.graphics.drawRect(0,0,target.width - margin,target.height - margin);
			mask.graphics.endFill();
			mask.x = mask.y = 600/2 - mask.width/2;
			target.mask = mask;
		}
		
		//will not be counted as a line
		protected function getHeight(x:int,y:int,sourceBitmapData:BitmapData):Number{
			//These must be tuned.
			var offsetY:Number = 50;//Tune
			var amplitude:Number = 10;//Tune
			var decay:Number = 0.4;//Tune
			var color:uint = sourceBitmapData.getPixel(x,y);
			var r:Number = color >> 16;
			var numerator:Number = amplitude*(Math.exp(r/(decay*255)) - 1);
			
			var dumper:Number = 1e-4;//Tune
			var denominator:Number = dumper*Math.pow(x-(sourceBitmapData.width/2),2) + 1;
			return numerator / denominator + offsetY;
		}
	}
}