flash on 2011-10-2

by kihon 02 Oct 2011

Embed

package 
{
    import flash.display.Bitmap;
    import flash.display.BitmapData;
    import flash.display.Sprite;
    import flash.events.MouseEvent;
    import flash.geom.Rectangle;
    import frocessing.color.ColorHSV;

    public class Main extends Sprite
    {
        private var bd:BitmapData;
        private var max:Number = 1.0;
        private var min:Number = 0.0;
        private var size:int = 256;
        private var minSize:int = 2;
        private var color:ColorHSV = new ColorHSV();
        
        public function Main()
        {
            bd = new BitmapData(size, size, false);
            addChild(new Bitmap(bd));
            
            stage.addEventListener(MouseEvent.CLICK, onMouseClick);
            onMouseClick();
        }
        
        private function onMouseClick(event:MouseEvent = null):void 
        {
            generateHeightmap(0, 0, size, Math.random(), Math.random(), Math.random(), Math.random());
        }
        
        public function generateHeightmap(x:int, y:int, size:int, tl:Number, tr:Number, bl:Number, br:Number):void
        {
            if (size < minSize)
            {
                var value:Number = (tl + tr + bl + br) / 4;
                color.gray(value * 256);
                bd.fillRect(new Rectangle(x, y, x + minSize, y + minSize), color.value);
            }
            else
            {
                var midPoint:Number = (tl + tr + bl + br) / 4 + getRandomHeight(size);
                if (midPoint < min) midPoint = min;
                if (max < midPoint) midPoint = max;
                var top:Number = (tl + tr) / 2;
                var bottom:Number = (bl + br) / 2;
                var left:Number = (tl + bl) / 2;
                var right:Number = (tr + br) / 2;
                
                size /= 2;
                generateHeightmap(x, y, size, tl, top, left, midPoint);
                generateHeightmap(x + size, y, size, top, tr, midPoint, right);
                generateHeightmap(x, y + size, size, left, midPoint, bl, bottom);
                generateHeightmap(x + size, y + size, size, midPoint, right, bottom, br);
            }
        }
        
        public function getRandomHeight(value:Number):Number
        {
            return (Math.random() - 0.5) * value / size; 
        }
    }
}