The way I read this was a bit different: NVidia actually is the only vendor that offers a performant, complete and relatively bug free implementation. For examp

The way I read this was a bit different: NVidia actually is the only vendor that offers a performant, complete and relatively bug free implementation. For example if you consider this http://gdcvault.com/play/1020791/ http://gdcvault.com/play/1020791/ presentation then it is relatively clear that most major innovations were first available as OpenGL extensions by NVidia. The playing field might have levelled somewhat with the introduction of vulkan, which eliminates a lot of code that had to reside in the driver before. The main reason why Mesa is unlikely to catch up is because the backend compiler code is platform specific, so unless NVidia decides to publish their platform specification, it is unlikely that they will achieve meaningful success. Even if NVidia did publish a specification and left driver development to the community it is unclear to me who would be willing to do the free work for them.