There was a bug where the count of used builtin uniform buffer objects
was not advanced. This caused another problem since vulkan requires
a certain alignment for the buffer. This commit fixes both of those
things.
using the vulkan functionality probably leads to less bugs.
Until now it was assumed that any image was in the rgba8 format,
which is of course not correct. Clearing a texture to white or black
should now work for any format.
niki