The power of 2 textures shouldn't be a problem. I just told them allready I have a folder of example images... Under no circumstances they are allowed to change the size unless they ask me about it first...

About the tutorial... It uses SDL again, and somehow most computers here have some working fast with SDL.

Can anyone tell me how to do some sort of loop over the pixels of an OpenGL texture and generate a mask accordingly?

Example:
- I have a texture.
- Do a for loop on each pixel.
- If the pixel is pink, add a black pixel on the same coordinates on the mask.
- Otherwise, add a white pixel on the same coordinates on the mask.

Or better yet:
- Load a texture.
- Do a loop on each pixel.
- If pink, change the color to the transparent color (like in gifs)
- Otherwise leave it the way it is.

I believe that should do the trick, but now.... how to do that?

Don't get me wrong here, but this time I want to do something without SDL. The previous school project was all SDL and I don't think the people juding my internship would like me using that again...