Quote Originally Posted by smitty3268 View Post
Yes, OpenGL broadcasts extensions. That's one of the key points everyone hated about it versus DirectX, which just guaranteed a certain functionality with a version #, with OpenGL you had all sorts of extensions.

It provides versions as well, but that is like a minimum set of guaranteed extensions, and then you can manually query for anything on top of that if you want.



Generally what you do is take some baseline feature set that you require - such as GL2, or GL3, etc. Then on top of that you do manual querying for any useful extensions you might want to use but that aren't guaranteed by the baseline version. You have to use those optionally, only if the driver provides what you want. Of course, you can ignore that step if baseline GL3 (for example) provides everything you need. It just depends on how much effort you want to go to, and exactly what your code can benefit from that isn't part of the standard versions. Making it worse is that often an extension will be present only on the NVidia or AMD drivers, with the other providing an equivalent that is just different enough to trip you up, so the recommendation is usually to stick with the standard versions as much as possible.

So the 9.1 driver absolutely added new extensions and other risky changes that the 9.0 driver didn't. The truly safe changes are provided in the monthly (now supposedly every two weeks) updates - 9.0.1, 9.0.2, etc.
well someone from mesa should confirm but i never see or find that a change at opengl level[extension or revision]that made in a point release unless it was available in the major release and fixes a bug/issue. I can be wrong ofc is not like i readed every changelog or commit history from mesa 1.0