Fast CUTS

perlin noise study.

click screen to toggle between forked ver. and original ver.

My version is ugly. Maybe numerical error causes it? Floats calculated in perlin noise function and integer values stored in bitmap data makes the difference I guess.

by codeonwort 28 Feb 2012

• Forked from christian's CUTS
• Diff: 58
• Related works: 2

Talk

christian at 04 Mar 2012 18:45
comment is a bit too long to be posted properly, so it's here http://mm4d.free.fr/div/comment.txt
codeonwort at 05 Mar 2012 08:47
I can see the difference of 2 octaves image and 1 + 1 merged image well. I thought if I calculate manually first and second octaves the result will be closer to original but seeing your snippet's middle-right (merged result) image I wonder I can avoid the result from being blurry when I use two bitmap data to store each octave image.
christian at 05 Mar 2012 17:40
seems like 1+1 octave won't look like 2 octaves, but using a blendmode like erase (ad.draw (ab, null, null, 'erase') instead of ad.merge ...) gives a good result, details of treshold are as smooth as using 2 octaves, even if the output pattern is slightly different

Tags

awesome math
Embed

/**
 * Copyright codeonwort ( http://wonderfl.net/user/codeonwort )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/tt84
 */

// forked from christian's CUTS
// perlin noise study for speed-up the effect
package
{
    import flash.geom.*;
    import flash.filters.*;
    import flash.display.*;
    import flash.events.Event;
    import flash.utils.getTimer;
    import net.hires.debug.Stats

    [ SWF (width = '465', height = '465', backgroundColor = '0xFFFFFF', frameRate = '30') ]
    public class CUTS extends Sprite
    {
        private var e : BitmapData = new BitmapData (465, 465, true, 0x00), s : BitmapData = e.clone ();
        private var c : ColorTransform = new ColorTransform (1, 1, 1, 0.99);
        private var b : BlurFilter = new BlurFilter (2, 2, 5);
        private var o : Array = [new Point (), new Point ()];
        private var t : Number;
        
        private var zero:Point = new Point(0, 0)
        private var mat:Matrix = new Matrix
        private var halfRect:Rectangle = new Rectangle(0, 0, e.width, e.height)
        private var octave1:BitmapData
        private var octave2:BitmapData
        
        private var original:Boolean = false
        
        public function CUTS ()
        {
            Wonderfl.disable_capture ();
            stage.scaleMode = 'noScale';
            
            octave1 = new BitmapData(e.width*2, e.height*2, true, 0x0)
            octave2 = octave1.clone()
            
            e.perlinNoise(200, 200, 1, 0xAAA, true, true, 7, true)
            octave1.copyPixels(e, e.rect, new Point)
            octave1.copyPixels(octave1, halfRect, new Point(e.width, 0))
            octave1.copyPixels(octave1, halfRect, new Point(0, e.height))
            octave1.copyPixels(octave1, halfRect, new Point(e.width, e.height))
            
            e.perlinNoise(200, 200, 2, 0xAAA, true, true, 7, true)
            octave2.copyPixels(e, e.rect, new Point)
            octave2.copyPixels(octave2, halfRect, new Point(e.width, 0))
            octave2.copyPixels(octave2, halfRect, new Point(0, e.height))
            octave2.copyPixels(octave2, halfRect, new Point(e.width, e.height))
            octave2.draw(octave1, null, null, 'subtract')
            octave2.threshold(octave2, octave2.rect, new Point, '==', 0xff000000)
            
            addChild (new Bitmap (s))
            addChild(new Stats)

            addEventListener (Event.ENTER_FRAME, render);
            stage.addEventListener('mouseDown', toggleRenderMode)
        }
        
        private function toggleRenderMode($:Event):void {
            s.fillRect(s.rect, 0x0)
            original = !original
        }

        private function render ($ : Event = null) : void
        {
            t = getTimer ();
            
            if(original){
                o[1].x =- (o[0].x = Math.sin (t * 0.00005) * 250);
                o[1].y =- (o[0].y = Math.cos (t * 0.00005) * 250);
                e.perlinNoise(200, 200, 2, 0xAAA, true, true, 7, true, o)
            }else{
                o[1].x =- (o[0].x = Math.sin (t * 0.0005) * 250);
                o[1].y =- (o[0].y = Math.cos (t * 0.0005) * 250);
                halfRect.x = -o[0].x % e.width
                halfRect.y = -o[0].y % e.height
                while(halfRect.x < 0) halfRect.x += e.width
                while(halfRect.y < 0) halfRect.y += e.height
                e.copyPixels(octave1, halfRect, zero)
                
                halfRect.x = -o[1].x % e.width
                halfRect.y = -o[1].y % e.height
                while(halfRect.x < 0) halfRect.x += e.width
                while(halfRect.y < 0) halfRect.y += e.height
                mat.identity()
                mat.translate(-halfRect.x, -halfRect.y)
                e.draw(octave2, mat, null, 'add')
            }
            
            e.threshold (e, e.rect, e.rect.topLeft, '!=', 0xFF808080, 0x00000000);
            e.applyFilter (e, e.rect, e.rect.topLeft, b);
            
            e.draw (e, null, null, BlendMode.ADD, null, true);
            e.draw (e, null, null, BlendMode.ADD, null, true);
            e.threshold (e, e.rect, e.rect.topLeft, '==', 0xFFFFFFFF, 0x00000000);
            
            s.colorTransform (s.rect, c);
            s.copyPixels (e, e.rect, e.rect.topLeft, null, null, true);
        }
    }
}