When the app self-manages the display transform (OAK_MACOS_LAYER_
COLORSPACE=display set at startup), the CAMetalLayer is tagged with the
main display's colorspace so ColorSync passes the already-transformed
pixels through — without the tag the OS would re-correct them (double
correction). The CoreGraphics FFI lives in its own module because the
build script forwards metal_renderer.rs FFI declarations into the
Metal shader header.
Mike-Solar
4067918c67