using 5 RGBA 32 bit floating pbuffers, all with own render context and wglSharedList with main rendering context.
//in fragment shader
uniform sampler2D LightingPointPosition;
varying vec2 TextureCoord;
void main(void) {
gl_FragColor = texture2D(LightingPointPosition, TextureCoord);
}
I bind a floating texture to a unit and set the uniform. Then I render the same thing in a for-loop to the different buffers and read the result back to check the result, and:
for the first pbuffer the first several thousands values are incorrect, some strange values, no idea where there are from, but after that there are the correct/same values like in my floating point texture. I checked the texture corrdinates and they are correct and should correspond for all pixels to the values from the original texture.
for the other pbuffer I only get (0,0,0,1) which afaik means no texture is bound? But I have, and I do for every pbuffer exactly the same thing, so how can the results differ?
Any ideas why the first several thousand values are not from the original texture, and why after the first pbuffer the others don’t work at all? If I loop the loop several times always the first buffer works half correctly, in the others I get the (0,0,0,1) values.
mhh, with some tests while writing this post I got several runnings with the several first pixels with strange values, and now without changing anything at the vertex-, texture coordinates, debug output log routine or the texture data got several runnings with the first pbuffer rendering completely correct values
I have the strange feeling there are some non-deterministic effects… Has anybody else already seen non-determinstic buggy behaviour with pbuffers/glsl on ATI? This is at least the third time where there is a really strange behaviour using glsl/pbuffer on ATI. Could this be a hardware issue? On the other hand, haven’t noticed any strange problems with games and so on, so either its a very strange driver bug or just some complex error reasons I don’t understand…
But indendent from this, the first buffer works(somehow) the others not is a quite reproducible problem till now…
using: Radeon 9800 + catalyst 4.11