Mesa is a key component of OpenGL support on open source platforms and just announced release 12.0.0. Major features of this release are Vulkan drivers for Intel chipsets, OpenGL 4.3 support on modern GPUs, OpenGL ES 3.1 support and more.
The 12.0.0 announcement from the Mesa developer mailing list:
It's a real honour to announce Mesa 12.0.0. This release has massive amount of features, but without a doubt the biggest ones are: - Vulkan driver for Intel hardware from Ivy Bridge onward. - OpenGL 4.3 for nvc0, radeonsi and i965 (Gen8+) - OpenGL ES 3.1 on nvc0 and radeonsi - GLVND support for GLX, OpenGL - New gallium software driver - SWR. - DRI3 enablement for VDPAU, OMX and VAAPI Note: - Gallium radeon drivers (r300, r600 and radeonsi) now require kernel 3.2 and LLVM 3.6 or later. - Building SWR requires python2, since some of the generated files cannot be distributed as part of the release tarball.