Microsoft Gets OpenGL 4.4 Running Atop Direct3D 12 Using Mesa, OpenGL 4.5 Inbound

It was just last week that Microsoft got OpenGL 4.3 implemented over Direct3D 12 for use in cases where Windows lacks a native OpenGL driver or for use under Windows Subsystem for Linux (WSLg). After implementing a few more GL extensions atop D3D12, Microsoft has now got OpenGL 4.4 in Mesa running on Direct3D.

Microsoft's Jesse Natalie who has been responsible for much of Microsoft's contributions to Mesa the past few years crossed off the OpenGL 4.4 milestone. With a dozen patches implementing ARB_enhanced_layouts, ARB_query_buffer_object, and ARM_texture_mirror_clamp_to_edge, the remaining extensions needed for OpenGL 4.4 compliance have been implemented.

Jesse Natalie noted that the OpenGL enhanced layout support in particular proved challenging for matching up the semantics of DirectX's DXIL intermediate language. More details on this OpenGL 4.4 support for D3D12 can be found via this merge.

OpenGL 4.5 atop D3D12 also looks like it will be landing soon for Mesa 24.0. This merge request from overnight will take D3D12 support to OpenGL 4.5. It turns out only another trivial four patches are needed for getting OpenGL 4.5 exposed on D3D12. With the Mesa 24.0 feature freeze / branching not for another two months, this OpenGL 4.5 support should land in plenty of time for this next feature series.