Microsoft Adds Mesa Support For Building Against The DirectX 12 Agility SDK
The DirectX 12 Agility SDK amounts to a re-distributable Direct3D 12 build. Rather than always tying new Direct3D features to new Windows versions, the Agility SDK breaks that link with this redistributable SDK build that applications can opt into without requiring users to upgrade their Windows installation for new graphics features.
So in the case of Mesa building against the D3D12 Agility SDK, it can opt into making use of newer D3D12 functionality without the Windows upgrade. This can be particularly useful for continuous integration (CI) testing/development purposes or those rolling their own Mesa Windows builds and not wanting to be forced to upgrade Windows.
Microsoft engineers added support for using the Agility SDK to their Mesa D3D12 driver. A follow-up merge added the Agility SDK support to their "Dzn" (Dozen) driver for Vulkan on D3D12.
These additions along with other improvements will be found as part of Mesa 22.3 being released as stable later this year.