Question

I want to modify the glBindTexture() function to keep track of the previously binded texture ID’s. At the moment i just created new function for it, but then i realised that if i use other codes that use glBindTexture: then my whole system might go down to toilet.

So how do i do it?

Edit: Now when i thought it, checking if i should bind texture or not is quite useless since opengl probably does this already. But i still need to keep track on the previously used texture.

Answer 1

One possibility is to use a macro to replace existing calls to glBindTexture:

#define glBindTexture(target, texture) myGlBindTexture(target, texture)

Then in you code, where you want to ensure against using the macro, you surround the name with parentheses:

(glBindTexture)(someTarget, someTexture);

A function-like macro is only replace where the name is followed immediately by an open-parenthesis, so this prevents macro expansion.

Since this is a macro, it will only affect source code compiled with the macro visible, not an existing DLL, static library, etc.