Errors are caught & reported by our GL debug callback. This gives us way more useful information than sporadic calls to glGetError.
I removed almost all use of glGetError, including our own GPU_ASSERT_NO_GL_ERRORS and GPU_CHECK_ERRORS_AROUND macros.
Still used in rna_Image_gl_load because it passes unvalidated input to OpenGL functions.
Still used in gpu_state_print_fl_ex as an exception handling hack -- will rewrite this soon.
The optimism embodied by this commit will not prevent OpenGL errors. We need to analyze what would cause GL to fail at certain points and proactively intercept these failures. Or guarantee they can't happen.
Old code had a mix of framebuffer error codes from OpenGL ES, EXT_framebuffer_object, and desktop GL. We use desktop GL (or ARB_framebuffer_object which acts just like GL 3.x) so I made it compatible with that.
Changed messages to the actual GL_FRAMEBUFFER_XXX symbols. These are less friendly and more accurate. Can easily look up what an error means, unfiltered by what a Blender dev thinks it means.
Kept ES error codes around in case we support that one day. Just flip the #if or use a compile-time option.
ARB_framebuffer_object replaces several related EXT extensions. The ARB
version pulls GL 3 FBO features into GL 2.1, useful for Mac platform.
Its functions and enums have no ARB suffix so transition to modern GL
will be seamless!
Extension is checked at startup, so is guaranteed to be true at runtime.
Part of T49012
