Getting normal information from OpenGL render output

Posted by okamiueru on Stack Overflow See other posts from Stack Overflow or by okamiueru
Published on 2010-06-11T21:54:19Z Indexed on 2010/06/12 15:02 UTC
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Filed under:

opengl

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fragment-shader

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normals

I'll try to keep this simple.

I want a way to access the normal information of the scene, from the Frame Buffer output (or similar). The same way one is able to access the Depth Buffer using glGetTexImage and GL_DEPTH_COMPONENT.

I know I could set up a fragment shader which outputs the normal information in RGB color space, which could in turn be read from the rendered image. I'm wondering however if there is a way to do this within the openGL API.

I'll clarify anything upon request as best as I can, Thank you

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