libplacebo is essentially the core rendering algorithms and ideas of
mpv turned into a library. This grew out of an interest to accomplish
the following goals:

- Clean up mpv's internal rendering abstraction API and make it
  reusable for other projects.
- Provide a standard library of useful GPU-accelerated image processing
  primitives based on GLSL, so projects like VLC or Firefox can use them
  without incurring a heavy dependency on libmpv.
- Rewrite core parts of mpv's GPU-accelerated video renderer on top of
  redesigned abstractions. (Basically, I wanted to eliminate stateful APIs like
  shader_cache.c and totally redesign gpu/video.c)