One more step towards BSP thread-safety. This one brought with it a very
noticeable speed boost (ie, not lost in the noise) thanks to the face
visframes being in tightly packed groups instead of 128 bytes apart,
though the sw render's boost is lost in the noise (but it's very
fill-rate limited).
This is next critical step to making BSP rendering thread-safe.
visframe was replaced with cluster (not used yet) in anticipation of BSP
cluster reconstruction (which will be necessary for dealing with large
maps like ad_tears).
The main goal was to get visframe out of mnode_t to make it thread-safe
(each thread can have its own visframe array), but moving the plane info
into mnode_t made for better data access patters when traversing the bsp
tree as the plane is right there with the child indices. Nicely, the
size of mnode_t is the same as before (64 bytes due to alignment), with
4 bytes wasted.
Performance-wise, there seems to be very little difference. Maybe
slightly slower.
The unfortunate thing about the change is the plane distance is negated,
possibly leading to some confusion, particularly since the box and
sphere culling functions were affected. However, this is so point-plane
distance calculations can be done with a single 4d dot product.
I doubt the calls were ever actually made in a normal map due to the
node actually being a node when breaking out of the loop, but when I
experimented with an empty world model (no nodes, one infinite empty
leaf) I found that visit_leaf was getting called twice instead of once.
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.
It being on the stack was a bad idea as R_RenderWorld returns before the
scans are rendered and thus the entity pointer winds up pointing to
abandoned stack space.
This moves the common camera setup code out of the individual drivers,
and completely removes vup/vright/vpn from the non-software renderers.
This has highlighted the craziness around AngleVectors with it putting
+X forward, -Y right and +Z up. The main issue with this is it requires
a 90 degree pre-rotation about the Z axis to get the camera pointing in
the right direction, and that's for the native sw renderer (vulkan needs
a 90 degree pre-rotation about X, and gl and glsl need to invert an
axis, too), though at least it's just a matrix swizzle and vector
negation. However, it does mean the camera matrices can't be used
directly.
Also rename vpn to vfwd (still abbreviated, but fwd is much clearer in
meaning (to me, at least) than pn (plane normal, I guess, but which
way?)).
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.
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.
This has several benifits:
o The silly issue with alias model pitches being backwards is kept out
of the renderer (it's a quakec thing: entites do their pitch
backwards, but originally, only alias models were rotated. Hipnotic
did brush entity rotations in the correct direction).
o Angle to frame vector conversions are done only when the entity's
angles vector changes, rather than every frame. This avoids a lot of
unnecessary trig function calls.
o Once transformed, an entity's frame vectors are always available.
However, the vectors are left handed rather than right handed (ie,
forward/left/up instead of forward/right/up): just a matter of
watching the sign. This avoids even more trig calls (flag models in
qw).
o This paves the way for merging brush entity surface rendering with the
world model surface rendering (the actual goal of this patch).
o This also paves the way for using quaternions to represent entity
orientation, as that would be a protocol change.
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.
