Is glCopyTexSubImage2D known to be broken on ATi?
I am trying to use glCopyTexSubImage2D to read from a floating-point pbuffer to a floating-point texture, and getting garbage results out. The same code works fine on NVIDIA GFX 5200 & 5950, and the data is correct (other than the 24-bit truncation due to the fragment program) if read via glReadPixels (but that won’t do as it reads to main memory).
These posts hint that i am not the only one with this problem: http://www.opengl.org/discussion_boards/cgi_directory/ultimatebb.cgi?ubb=get_topic;f=3;t=011988
http://www.opengl.org/discussion_boards/cgi_directory/ultimatebb.cgi?ubb=get_topic;f=3;t=008133
I am using the May 12 Catalyst driver on a Radeon 9800XT; Windows Server 2003.
Also, if glCopyTexSubImage2D is indeed broken, is there a recommended workaround (other than, of course, installing an NV card)? Is there a (low) limit on the number of pbuffers that can exist at once?
Thanks,
Peter