Render on other render targets starting from one already rendered on

Posted by JTulip on Game Development See other posts from Game Development or by JTulip
Published on 2014-06-12T12:50:36Z Indexed on 2014/06/12 15:43 UTC
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I have to perform a double pass convolution on a texture that is actually the color attachment of another render target, and store it in the color attachment of ANOTHER render target. This must be done multiple time, but using the same texture as starting point

What I do now is (a bit abstracted, but what I have abstract is guaranteed to work singularly)

renderOnRT(firstTarget); // This is working. 

for each other RT currRT{
    glBindFramebuffer(GL_FRAMEBUFFER, currRT.frameBufferID);    
    programX.use();
    glActiveTexture(GL_TEXTURE0);
    glBindTexture(GL_TEXTURE_2D, firstTarget.colorAttachmentID);
    programX.setUniform1i("colourTexture",0);
    glActiveTexture(GL_TEXTURE1);
    glBindTexture(GL_TEXTURE_2D, firstTarget.depthAttachmentID);
    programX.setUniform1i("depthTexture",1);
    glBindBuffer(GL_ARRAY_BUFFER, quadBuffID); // quadBuffID is a VBO for a screen aligned quad. It is fine.
    programX.vertexAttribPointer(POSITION_ATTRIBUTE, 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
    glDrawArrays(GL_QUADS,0,4);

    programY.use();
    glActiveTexture(GL_TEXTURE0);
    glBindTexture(GL_TEXTURE_2D, currRT.colorAttachmentID); // The second pass is done on the previous pass
    programY.setUniform1i("colourTexture",0);
    glActiveTexture(GL_TEXTURE1);
    glBindTexture(GL_TEXTURE_2D, currRT.depthAttachmentID);
    programY.setUniform1i("depthTexture",1);
    glBindBuffer(GL_ARRAY_BUFFER, quadBuffID);
    programY.vertexAttribPointer(POSITION_ATTRIBUTE, 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
    glDrawArrays(GL_QUADS, 0, 4);
}

The problem is that I end up with black textures and not the wanted result.

The GLSL programs program(X,Y) works fine, already tested on single targets.

Is there something stupid I am missing?

Even an hint is much appreciated, thanks!

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