tested on 135 and 157

NVIDIA GeForce 7600 GT (iMac)


<code>

import processing.opengl.*;

void
setup() {
size(512, 512,OPENGL);
loadPixels();
for(int j = 0 ; j < height; j++) for(int i =0; i < width; i++)
pixels[i+j*width] = int(random(100));

}

void
draw() {
if (mousePressed) {
pixels[mouseX+mouseY*width] = color(255,0,0);
}
updatePixels();
}


</code>

edit]
image showing the mirroring

loadPixels and updatePixels have to be used together. you can't call
loadPixels() once, and then keep calling updatePixels() inside draw()
repeatedly. you need loadPixels() at the top of draw(), and updatePixels()
at the end.

OK, thanks Ben.

I had lost the habit of doing so as calling loadPixels only once seems to
work quite nicely in the default rendering mode (and in P2D), with a slight
speed gain even.