Since Vulkan is now enabled in Windows nightly builds and therefore is accessible to a wider audience, I figured I should share this information Twinaphex told me in IRC on the forums.
Shaders written for RetroArch’s non-Vulkan rendering drivers, such as Cg and GLSL shaders, do not work with RetroArch’s Vulkan driver. There is a draft of RetroArch’s new shader specification written up by Themaister (original SSNES/RetroArch dev, and also the main RetroArch Vulkan driver dev) here:
There is a number of example shaders written by Themaister already in the same repository, here:
Just like “.cg”/".glsl" and “.cgp”/".glslp", “.slang” files are individual shader passes and “.slangp” files are shader presets which can be loaded to add and configure any number of passes. These files are currently usable in RetroArch with Vulkan.
I hope this helps people who want to play with Vulkan!