Move r_pcurrentvertbase into the sw renderer, cleaning up gl's use of
(not really needed there). Not ready to move r_bsp into the main bin yet
as there are linking issues since only the low-level code references any
of its symbols.
While the scheme of using our own allocated did work just fine, fisheye
rendering uses glGenTextures which caused a texture id clash and thus
invalid operations (the cube map texture happened to be the same as the
console background texture). Sure, I could have just "fixed" the fisheye
init code, but this brings gl closer in line with glsl (which makes
extensive use of glGenTextures and glDeleteTextures). This doesn't fix
any texture leaks gl has (plenty, I imagine), but it's a step in the
right direction.
Finally. I never liked it (felt bad adding it in the first place), and
it has caused confusion with function and global variable names, but it
did let me get the render plugins working.
This is a big step towards a cleaner api. The struct reference in
model_t really should be a pointer, but bsp submodel(?) loading messed
that up, though that's just a matter of taking more care in the loading
code. It seems sensible to make that a separate step.
Where possible, symbols have been made static, prefixed with gl_/GL_ or
moved into the code shared by all renderers. This will make doing plugins
easier but done now for link testing.