Accessing frame buffer

I did not seen any built in variable to access currently rendered pixel color and depth - I mean not the currently processed pixel but already processed pixel, available in the frame buffer (in case of a multipasse rendering).
What I’m talking about would be a kind of gl_FragColor or gl_FragDepth but giving current frame buffer color and depth for the current pixel processed. Do you know how to access it ?

Right now there’s no possibility to access the frame buffer. If you use multipass techniques you have to use textures right now.

Long time your posts are ago. So, is there now a possibility to access the framebuffer like you said in the topic??

thx

I believe this issue was considered a long time ago when they were designing GLSL. They talked about having built-in variables gl_FBColor, gl_FBDepth, and gl_FBStencil. From what I’ve read, they decided against these variables because they would be impractical to implement and have poor performance.

Have a look at issues 7 and 23 at the bottom of the GLSL spec. http://oss.sgi.com/projects/ogl-sample/registry/ARB/GLSLangSpec.Full.1.10.59.pdf

Alright, then I have to find a different solution.

Thanx anyway

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