How to load Pixel Bender in Flash Player 10

May 19, 2008

How to load Pixel Bender in Flash Player 10

Category: as3, flash — joshspoon @ 8:30 am —

Hey so I spent most of the weekend trying to get Senocular's tutorial on loading .pbj into flash player 10.

For some reason it wasn't working for me so I decided to download Pixel Bender Preview Release and copy the file's source code and export it (File > Export Pixel Bender...for Flash) and it worked so I wanted to post it. Just in case some one had the same problem.

AS FILE:

PLAIN TEXT

Actionscript:

package {
import flash.display.*;
import flash.events.*;
import flash.net.URLLoader;
import flash.net.URLLoaderDataFormat;
import flash.net.URLRequest;
import flash.utils.ByteArray;
import flash.utils.getTimer;
public class astro2 extends Sprite
{
// image for shader fill
private var _bitmap:Bitmap;
// shader fill shader; it will use
// the image as an input
private var _shader:Shader;
// loader to load pixel bender bytecode
// for shader instance
private var _shaderLoader:URLLoader
private var _loader:Loader
public function astro2()
{
//load image
stage.align = StageAlign.TOP_LEFT;
stage.scaleMode = StageScaleMode.NO_SCALE;
_loader = new Loader();
_loader.contentLoaderInfo.addEventListener(Event.COMPLETE, onImgLoad, false, 0, true);
_loader.load(new URLRequest("http://bp2.blogger.com/_Y8m29ZLX5ag/RarR3rcAVwI/AAAAAAAAAL4/dtA7xOMrI4g/s400/ASTRO_jpg.jpg"));
}
//once loaded load Pixel Bender File
private function onImgLoad(evt:Event):void
{
_bitmap = Bitmap(_loader.content);
_shader = new Shader();
_shaderLoader = new URLLoader();
_shaderLoader.dataFormat = URLLoaderDataFormat.BINARY;
_shaderLoader.addEventListener(Event.COMPLETE, shaderLoaded);
_shaderLoader.load(new URLRequest("test.pbj"));
}
// shaderLoader complete handler
private function shaderLoaded(event:Event):void {
// set up shader
_shader.byteCode = _shaderLoader.data as ByteArray; // error if invalid
_shader.data.src.input = _bitmap.bitmapData; // image input
_shader.data.size.value = [100]; // constant size
_shader.data.fade.value = [.5]; // constant fade value
// draw the shader every frame
addEventListener(Event.ENTER_FRAME, drawKaleidoscope);
}
// enterframe handler
private function drawKaleidoscope(event:Event):void {
// base position on mouse location
_shader.data.position.value = [mouseX, mouseY];
// rotate constantly over time
_shader.data.angle.value = [getTimer()/500];
// draw a rectangle with the shader fill
graphics.clear();
graphics.beginShaderFill(_shader);
graphics.drawRect(0,0,300,250);
}
}
}

and the Pixel Bender code:

kernel Kaleidoscope
< namespace : "Petri Leskinen";
version : 1;
vendor : "";
description : "kaleidoscope -effect, rectangular";
>
{
parameter float4 fadeColor
<
minValue: float4(0,0,0,0);
maxValue: float4(1,1,1,1);
defaultValue: float4(0,0,0,1);
description: "Fade color";
>;
parameter float2 position
<
minValue: float2(0,0);
maxValue: float2(2880,2880);
defaultValue: float2(250,280);
description: "Center point";
>;

parameter float size
<
minValue: float(1);
maxValue: float(500);
defaultValue: float(75);
description: "Size";
>;

parameter float fade
<
minValue: float(0.5);
maxValue: float(1.0);
defaultValue: float(1.0);
description: "Fade";
>;

parameter float angle
<
minValue: float(-3.14159);
maxValue: float(3.14159);
defaultValue: float(0.5);
description: "Rotation angle";
>;

input image4 src;
output pixel4 dst;

void evaluatePixel()
{
float sina = sin(angle);
float cosa = cos(angle);

float2 newC = position - size/2.0* float2(cosa+sina, cosa-sina);

// mx matrix for rotation and scaling
// mxR reverse transformation
float2x2 mx = float2x2( cosa,sina,-sina,cosa) /size;
float2x2 mxR = float2x2( cosa,-sina,sina,cosa) *size;

// coordinate p1 on the new coordinate system,
// on the center area 0.0 < p1.x < 1.0 , 0.0 < p1.y < 1.0
float2 p1 = mx * (outCoord() -newC);

// p2 integer part, p1 only decimal part,
// which maps every pixel to the center area
float2 p2 = floor(p1);
p1 = fract(p1); // p1 -= p2;

// p3 dislocation for mirroring,
// mirrored if integer part odd
float2 p3 = 1.0-2.0*p1;
p1.x += mod (p2.x,2.0) > 0.0 ? p3.x : 0.0 ;
p1.y += mod (p2.y,2.0) > 0.0 ? p3.y : 0.0 ;

// reverting to the main coordinate system, sampling and mixing the pixel
p1 = newC + mxR*p1;
dst = mix( fadeColor, sampleLinear(src,p1) ,
pow ( fade,abs(p2.x)+abs(p2.y)) );

}
}