Hi all

I need your help and advices here

I discovered processing a few days ago and programmed a pattern generation tool with it. Programmed in one night, it was used for live visuals during a party on 4 screens driven by 2 MacBooks and one PC laptop.

You can have an idea of the thing here :
http://www.youtube.com/watch?v=gmpb9YYEPLU

The basic idea is to generate a pattern that can be slightly or completely different at each frame, then scale it, rotate it, and pave the whole screen with that pattern.

However i am facing a performance issue. therefore i am looking for some advices. I am unsure which approach to choose. so far i tried :

-use size(x,y) rotate() and scale() the referential and draw each pattern in using triangle(),quad().

-same as above but with size(x,y,OPENGL)

-use size(x,y) and draw the pattern once in a PGraphics object and replicate it on screen.

-same as above but with size(x,y,OPENGL)

None of these where fast enough. and i believe that with today's computer and using openGL, i could either:

- build up on the fly a texture of the pattern, make a quad() of the size of the screen, and pave it with the texture. however i didn't an option to make the texture repeat itself on the object. I didn't manage to use Pgraphics object as quad() texture anyways

- Draw each shape of the pattern using openGL triangles and fill them with the appropriate color. I thought switching to size(x,y,OPENGL); would do the trick. But when i look at the performance it seems it didn't

i am surely missing some basic thing here.

Any ideas or thoughts ?

PS: if some of you are interested, i can send you the source.

henri

like i said i used processing only a few hours, so i am not really familiar with this openGL thingie yet.

but i'll try to look in to this then ! thanks !

in the mean time other advices are welcome too :)


edit:
quickly tried this coordinate >1 and it does not work. it repeats the border of the texture. i tried this
import processing.opengl.*;
import javax.media.opengl.*;
import com.sun.opengl.util.texture.*;  

Texture tex;  

void setup()  
{  
 size(1200,800, OPENGL);
 try{
  tex=TextureIO.newTexture(new File(dataPath("lines.IMG_2301.taglight.tagsmoke.JPG")),true); }
 catch(Exception e) { println(e); }
}  

void draw()  
{  
 if(tex!=null){
 background(128);
 PGraphicsOpenGL pgl = (PGraphicsOpenGL) g;  
 GL gl = pgl.beginGL();  
 tex.bind();  
 tex.enable();  
 gl.glBegin(GL.GL_QUADS);
 gl.glNormal3f( -1.0f, -1.0f, -1.0f);
 gl.glTexCoord2f(0, 0); gl.glVertex2f(0,500);
 gl.glTexCoord2f(2, 0); gl.glVertex2f(500, 500);
 gl.glTexCoord2f(2, 2); gl.glVertex2f(500, 0);
 gl.glTexCoord2f(0, 2); gl.glVertex2f(0, 0);
 gl.glEnd();  
 tex.disable();
 pgl.endGL();
 }
}

how would you use this in processing ?
i tried :

 gl.glTexParameterfv(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_S_WRAP, GL.GL_REPEAT);  
 gl.glTexParameterfv(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_T_WRAP, GL.GL_REPEAT);
 

c:/temp/build29781.tmp/Temporary_1699_8000.java:24:44:24:60: Semantic Error: No accessible field named "GL_TEXTURE_T_WRAP" was found in type "javax.media.opengl.GL".

thanks !
works,

i now have to find a way to build the texture on the fly from a PGraphics object instead of a file ?
tex=TextureIO.newTexture(new File(dataPath("lines.IMG_2301.taglight.tagsmoke.JPG")),true);


any idea ?

Texture has an updateImage method that takes a TextureData which has the usual width, height, data. you could fill this TextureData from a PGraphics object (or render directly to it) and then call updateImage for your texture. very low level though and you may lose a lot of the speed increase doing this.

http://download.java.net/media/jogl/builds/nightly/javadoc_public/com/sun/opengl/util/texture/Texture.html

i have to say i am pretty surprised there is no way to tile a texture over an object in processing. but that is maybe the price to pay to have such a simple and easy to use piece of software

The other approach would be to draw each triangle in openGL.
my goal is to be able to draw about a maximum 100*100 patterns on screen. each pattern is made of nine shape. each shape is about 3 triangles in average.

so it would be about 300 000 triangles untextured per frame.
is that unrealistic ?

hum, i think i'll stick to my first version (rendered shapes via the normal processing API) and then and try to improve it. as it seems that using lowlevel openGL to repeat the texture will cause more harm than it will help.

if there are any tips for improving performance while drawing many shapes on screen, please tell me

hi !

i put the code available to all there (lets consider it's GPL ):
http://motscousus.com/stuff/2008-02_Processing.org_patterns/

this it the version that draws the shape on screen using normal processing triangle(); quad(); and fill() methods.


what are these opengl display lists ?