[PyOpenGL-Devel] [ pyopengl-Bugs-3611878 ] compileProgram validates against opengl state

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Bugs item #3611878, was opened at 2013-04-25 19:50
Message generated for change (Comment added) made by xwize
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Category: GL
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: xwize (xwize)
Assigned to: Mike C. Fletcher (mcfletch)
Summary: compileProgram validates against opengl state

Initial Comment:
The compileProgram function calls check_validate on the newly linked program object which can lead to a situation where
validation fails due to an incompatible gl state, yet there are no errors reported in either compiling or linking. 

Validation should only be performed before *using* the shader program - so as to check whether or not the shader will execute correctly with the current opengl state and not to be used as an indication of compilation success.

If validation fails due to an incompatible state, but shader compilation and linking succeeds, it causes a catch-22 because the function throws an error and you can't change the state if you aren't returned the linked program.


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>Comment By: xwize (xwize)
Date: 2013-04-25 20:00

Message:
"RuntimeError: Validation failure (0): Validation failed! - Different
sampler types for same sample texture unit in fragment shader." <-
Validation can fail despite there being nothing wrong with shader
compilation or linking.

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You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=105988&aid=3611878&group_id=5988