Vulkan 1.2.158 Released With Fragment Shading Rate Extension

Vulkan 1.2.158 was released this morning with two notable extensions introduced.

First up is VK_KHR_fragment_shading_rate that allows changing the rate at which fragments are shaded. Multiple pixels can be shaded now by a single fragment shader invocation. The new extension allows controlling the fragment shading rate on a per-draw, per-primitive, or per-region basis. Most notably this can be used by Vulkan-powered games for shading higher levels of detail in a scene compared to others. Or rather lower quality shading in some areas of the scene.

Similar behavior is already being used by newer Windows games with Direct3D while VK_KHR_fragment_shading_rate will be important for Vulkan games moving forward. VK_KHR_fragment_shading_rate was worked on by AMD, NVIDIA, Intel, Arm, and Qualcomm.

VK_KHR_shader_terminate_invocation is the other new extension and is for exposing SPIR-V terminate invocation support. This causes a shader invocation to immediately terminate and sets the coverage of shaded samples to zero.

There are also several specification clarifications/fixes as part of this Vulkan 1.2.158 release.