I meant to do this a while ago but forgot about it. Things are a bit of
a mess in that the renderer knows too much about entities, but
eventually the renderer will know about only things to render (meshes,
particles, etc).
r_refdef is really meant for holding the various screen "constants" for
the software renderer rather than the more generic scene stuff. All the
fields referenced by the low level rendering code (especially assembly)
have been moved to the beginning of the struct (and nicely fit within 64
bytes). The other fields should be moved elsewhere, but not this commit.
On top of that, R_ViewChanged is much easier to read, and there are
fewer static globals.
This is the first step towards component-based entities.
There's still some transform-related stuff in the struct that needs to
be moved, but it's all entirely client related (rather than renderer)
and will probably go into a "client" component. Also, the current
components are directly included structs rather than references as I
didn't want to deal with the object management at this stage.
As part of the process (because transforms use simd) this also starts
the process of moving QF to using simd for vectors and matrices. There's
now a mess of simd and sisd code mixed together, but it works
surprisingly well together.
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.
I got rather tired of there being multiple definitions of mostly compatible
plane types (and I need a common type anyway). dplane_t still exists for
now because I want to be careful when messing with the actual bsp format.
