Lavapipe CPU-Based Vulkan Ported To Windows

Lavapipe as Mesa's CPU-based Vulkan driver implementation akin to LLVMpipe for OpenGL can now run on Microsoft Windows.

For the past few months there has been this Windows/Win32 port in progress for getting Lavapipe to run on Windows. This was started off by an independent developer but then ultimately assisted by Microsoft's Jesse Natalie who has been working on Microsoft's other Mesa initiatives.

In the past week the code finally began working, including to render the basic Vulkan cube on Windows:

Getting this software-based Vulkan implementation working on Windows also included implementing the Windows Vulkan windowing subsystem integration (WSI) as the first Mesa Vulkan driver running on Windows (still out-of-tree is also the work getting RADV on Windows).

The work on porting Lavapipe to Windows that is now merged into Mesa 21.1 can be found via this merge request.