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Index › Programming Questions & Help › Syntax Questions › Code does not work in OPENGL

domi YaBB Newbies Offline Posts: 9

Code does not work in OPENGL Dec 24th, 2009, 4:23am   Hi, I try to experiment a little bit with loadPixels and updatePixels and I don't know why that code works in every render mode, except OPENGL...   can anyone tell me why? import processing.opengl.*; int[] tmpFrame; void setup() {  colorMode(HSB);  frameRate(30);  size(600, 600, OPENGL);  noStroke();  smooth();  tmpFrame = new int[width * height];  background(0);  fill(240, 0, 250); } void draw() {  ellipse(mouseX, mouseY, 20, 20);        loadPixels();  work(pixels, tmpFrame, width, height);  arrayCopy(tmpFrame, pixels);  updatePixels(); } void work(int[] src, int[] dst, int w, int h) {  int c;  int r, g, b;  for(int i = 0; i < src.length; i++){    dst[i] = (src[i] << 1);  } }

koogy God Member Offline Posts: 788	Re: Code does not work in OPENGL Reply #1 - Dec 24th, 2009, 4:53am   could be because with opengl all the rendering is done on the graphics card and processing doesn't have (easy / quick) access to the pixels

domi YaBB Newbies Offline Posts: 9	Re: Code does not work in OPENGL Reply #2 - Dec 25th, 2009, 1:38am   Well... but how to solve it?

PhiLho  YaBB Moderator Offline Posts: 4190 Near Paris (France)	Re: Code does not work in OPENGL Reply #3 - Dec 25th, 2009, 2:35am   I don't know well OpenGL, but a possible way might be to draw the pixels in a PGraphics and use it as a texture. If I am wrong, 3D specialists just correct me.

domi YaBB Newbies Offline Posts: 9	Re: Code does not work in OPENGL Reply #4 - Dec 26th, 2009, 5:02am   Hmm... reference says its not allowed to create PGraphics with opengl...

PhiLho  YaBB Moderator Offline Posts: 4190 Near Paris (France)	Re: Code does not work in OPENGL Reply #5 - Dec 26th, 2009, 6:38am   Precisely for the reasons above, I suppose. PGraphics are off-screen graphics, so an OpenGL version makes no sense, since the latter is managed by GPU, ie. on screen. But I was thinking of making a graphic in some other mode (ie. make a good old bitmap) then using it, if possible, in OpenGL.

0p0 Junior Member Offline Posts: 63 Costa Rica	Re: Code does not work in OPENGL Reply #6 - Dec 27th, 2009, 1:15pm   Problems are always around when not updating the background when using OPENGL renderer. if you put a background() command in the begining of draw(), the drawing is done, but, of course, you loose the original and nicer drawings... To where my knowledge goes, I think there is no workaround for this.

domi YaBB Newbies Offline Posts: 9	Re: Code does not work in OPENGL Reply #7 - Dec 28th, 2009, 12:04am   Its a pity that it wont work, like I imagined *G* anyway thanks for all your answers