Group the variable state up into its own struct, which also includes
metadata like whether or no...

Also add some versioning policy. Basically, the policy I've decided on:

1. majorver has abstrac...

This is supposed to be column major, but it seems I just flat out forgot
to swap the indices whe...

No reason to keep them around.

I just realized this depends on `src_luma`, which is a privately defined
variable. It also doesn...

Had a typo for vec4 causing it to be treated as vec3

Was missing 'extern'

Uses pretty much the same inferrence logic as mpv's gpu/video.c;
although we arrive at the concl...

They look sort of ugly in the HTML rendered version.

Code shamelessly stolen from mpv, except without all the awful parts.
(Just kidding, I still lov...