RADV Vulkan Driver Now Supports VK_EXT_discard_rectangles

RADV co-founder Bas Nieuwenhuizen has landed support for the Vulkan VK_EXT_discard_rectangles extension within Mesa 17.4-dev.

VK_EXT_discard_rectangles is the extension introduced last February with the bug Vulkan 1.0.42 update. EXT_discard_rectangles allows for discarding rectangles in the frame-buffer space to restrict rasterization of points/lines/triangles.

To date on the Linux side I'm only aware of the NVIDIA proprietary driver supporting this extension. But with that said I'm also not aware of any Vulkan Linux games/applications yet using this extension either: in the commit Bas just mentions testing a modified deferred demo. Nevertheless, it's another Vulkan extension in place for this open-source Radeon Vulkan driver for the Mesa 18.0 release later this quarter. In addition to this extension, a few other RADV commits have also been committed very recently to the codebase too.