screenshot is of an emacs frame open with the buffers described in the post. the example project is called strigiforme, and is written in c++. the code deals with color & surfaces.
https://media.bloodyno.se/media/984b1e6e2abc43b950e7d46e04f4c6f3c9ec0f872fc59be21d6aacc6b22a8349.png