We use that representation to produce the DXIL bytecode consumed by DirectX. Mesa will also translate GLSL shaders into an intermediate representation named NIR.

On the shader side, the state tracker is able to convert OpenGL fixed-functions, traditionally implemented directly by the hardware, into shaders. The 'D3D12 Driver' is thus an implementation of that interface. The Mesa state tracker is responsible for translating OpenGL state (blend modes, texture state, etc) and drawing commands (like glDrawArrays and glDrawPixels) into objects and operations that map well to modern GPU hardware features (Gallium API). People familiar with that project will therefore experience a strong dГ©jГ -vu feeling when looking at the architecture of our current effort: Zink, a project started by Erik Faye-Lund, has already proven that we could achieve a similar goal: translating OpenGL to a lower-level graphics API (s/Vulkan/DirectX12/). In the initial steps of this project, we quickly realized that the best way forward was to build on top of Mesa.

Time for a summer update! In this blog post, I will explain a little more about the OpenGL part of this work and more specifically the steps that have been taken to improve the performance of the OpenGL-On-D3D12 driver. Earlier this year, we announced a new project in partnership with Microsoft: the implementation of OpenCL and OpenGL to DirectX 12 translation layers ( Git repository).

Directx opengl driver update