Do you guys think that Apple will keep adding new GL extensions with 10.11 or just stop porting of Open GL and focus on Metal for Mac OS X? It seems like Open GL development is going the same direction as Metal/Mantle/DX12. A complete rewrite. So would it make sense to spend time on porting the remaining 4.X GL versions to OS X? It should take some time before Open GL 5 (NG) is ready since it's a rewrite. Until then, Apple may be able to get Metal as sophisticated as Open GL for OS X instead.