Fixes LIT (https://bugs.dolphin-emu.org/issues/13635). The text does not include normals, but has lighting enabled. With the previous default of (0, 0, 0), lighting was always black (as dot(X, (0, 0, 0)) is always 0). It seems like the normal from the map in the background (0, 0, 1) is re-used.
LIT also has the vertex color enabled while vertex color is not specified, the same as SMS's debug cubes; the default MissingColorValue GameINI value of solid white seems to work correctly in this case.
SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
Now that we've extracted all of the stateless functions that can be
hidden, it's time to make the index generator a regular class with
active data members.
This can just be a member that sits within the vertex manager base
class. By deglobalizing the state of the index generator we also get rid
of the wonky dual-initializing that was going on within the OpenGL
backend.
Since the renderer is always initialized before the vertex manager, we
now only call Init() once throughout the execution lifecycle.