I've looked (briefly) at your(?) code.
A couple of things I will point out:
1) Firstly, there's only 3 instance that I can see of error checking. I'm not convinced yet that you've really tried to discover where the problem is.
I don't see a single call to glError
2) The data that the program depends on is not given nor explained. Depending on my mood I'll try to fix a program, but rarely, if ever, am I prepared to try to determine what the necessary feed-data is. How do I know that's not part of the
error, after all?
Have you tried to trim the program back to the simplest program that will display a (fixed-pipeline) shaded quad?
Something else that's just occurred to me - what's the result of the attempt to compile and use the shader program? My laptop supports OpenGL 2.1, however it only supports GLSL version 1.2
Perhaps you've used code in your shader that is not supported by the GLSL implementation that you have? I'm certainly nobody to ask on things glsl related..
But depending on the setup of the environment and the polygons within it - you could see nothing as a direct consequence of the shaders not being compiled/linked correctly.
Looks like time you did some more investigating and less question-asking for a short-time. Don't suppose that this is an example of copy/paste programming is it?
Lastly, what's with the crazy-a$$ link you gave above?
The link you provide points to a page at code project. So, what's the go with http://bit.ly/ny5IMa
and not the http://www.codeproject.com/script/Answers/Entry.aspx?aid=221622
] that it is?