OpenEmuShaders is a framework for rendering multi-pass post processing effects using Metal.
OpenEmuShaders can load presets from the slang-shaders project, providing access to an impressive library of effects, such as CRT-Royale
These effects are written in glsl, however, OpenEmuShaders makes use of glslang and SPIRV-Cross to transfrom the .glsl shaders into Metal Shader Language.