conwidth and conheight have been moved into vid.conview (probably change
the name at some time), and scr_vrect has been replaced by a view as
well. This makes it much easier to create 2d elements that follow the
screen size (taking advantage of a view's gravity) which will, in the
end, make changing the window size easier.
This separate the FOV calculations from other refdef calcs, cleaning up the
renderer proper and making it easier for other parts of the engine (eg,
csqc) to update the fov.
Things are still a mess, but a proper cleanup will be a lot of work and
will, really, involve properly splitting quake-specific code* out from
the rest of the renderer.
* data loading and format specific stuff
Still, nothing will work: no plugins are loaded and they're all broken
anyway.
glx, sgl, glslx etc are going away, just the basics will be built: fbdev
(probably go away eventually), sdl, x11 and hopefully someday win. That's
actually the only reason anything links.