Correct dimensions of Pygame components

I have modified Display3D to show pygame components in their requested dimesions. This is done by making the surface dimensions the next power of two but showing only the actual component area. But unfortunately, since the mouse collision tests are done inside the components (e.g. button) and against the surface size, this causes a problem.

Maybe it would be a better approach to use correct sized component surfaces and blit them onto a power-of-2 surface before it is used as texture.