Question

I’m writing my Master’s thesis on automatic portability testing and was wondering whether there were any automatic testing software for game developers when they’re developing a game with both OpenGL and DirectX support? Theoretically one could record the screen during the automatic run of a specific sequence in the game and analyze both OpenGL and DirectX recordings but is there some technical aspect which makes this impossible?

Answer 1

The closest thing I can think of are the tests in Wine, which do something along these lines.

Unfortunately, proper testing like this isn’t possible; the tests are far too dependent on system state and implementations aren’t guaranteed to be pixel-identical. DirectX does offer the reference implementation, which can be used for many testing uses, but I don’t know of an OpenGL equivalent.

Recording the screen introduces even more error, depending on how it’s performed. The tests I’ve seen render an image, then work from the texture data (similar to screen recording, but on a single frame and potentially more precise). Still, the whole thing is prone to quite a bit of error and can be slow.