While it takes one extra step to grab the marksurface pointer,
R_MarkLeaves and R_MarkLights (the two actual users) seem to be either
the same speed or fractionally faster (by a few microseconds). I imagine
the loss gone to the extra fetch is made up for by better bandwidth
while traversing the leafs array (mleaf_t now fits in a single cache
line, so leafs are cache-aligned since hunk allocations are aligned).
This is an extremely extensive patch as it hits every cvar, and every
usage of the cvars. Cvars no longer store the value they control,
instead, they use a cexpr value object to reference the value and
specify the value's type (currently, a null type is used for strings).
Non-string cvars are passed through cexpr, allowing expressions in the
cvars' settings. Also, cvars have returned to an enhanced version of the
original (id quake) registration scheme.
As a minor benefit, relevant code having direct access to the
cvar-controlled variables is probably a slight optimization as it
removed a pointer dereference, and the variables can be located for data
locality.
The static cvar descriptors are made private as an additional safety
layer, though there's nothing stopping external modification via
Cvar_FindVar (which is needed for adding listeners).
While not used yet (partly due to working out the design), cvars can
have a validation function.
Registering a cvar allows a primary listener (and its data) to be
specified: it will always be called first when the cvar is modified. The
combination of proper listeners and direct access to the controlled
variable greatly simplifies the more complex cvar interactions as much
less null checking is required, and there's no need for one cvar's
callback to call another's.
nq-x11 is known to work at least well enough for the demos. More testing
will come.
For now, the functions check for a null hunk pointer and use the global
hunk (initialized via Memory_Init) if necessary. However, Hunk_Init is
available (and used by Memory_Init) to create a hunk from any arbitrary
memory block. So long as that block is 64-byte aligned, allocations
within the hunk will remain 64-byte aligned.
Mod_DecompressVis_set (via Mod_LeafPVS_set) can be used to recycle pvs
sets, but the set may have been set to everything at some stage, which
is implemented by inverting the set (making the set infinite) and having
1-bits remove elements from the set. This is most definitely not wanted
for pvs :)
Currently undecided what to do about Mod_DecompressVis_mix, thus the
fixme.
Fixes the flickering lights in any map where the camera is out of the
map for a single frame (eg, start.bsp, The Catacombs (hipnotic, hip2m3)).
The fact that numleafs did not include leaf 0 actually caused in many
places due to never being sure whether to add 1. Hopefully this fixes
some of the confusion. (and that comment in sv_init didn't last long :P)
Modern maps can have many more leafs (eg, ad_tears has 98983 leafs).
Using set_t makes dynamic leaf counts easy to support and the code much
easier to read (though set_is_member and the iterators are a little
slower). The main thing to watch out for is the novis set and the set
returned by Mod_LeafPVS never shrink, and may have excess elements (ie,
indicate that nonexistent leafs are visible).
This gets the shaders needed for creating shadow maps, and the changes
to the lighting pipeline for binding the shadow maps, but no generation
or reading is done yet. It feels like parts of various systems are
getting a little big for their britches and I need to do an audit of
various things.
Double benefit, actually: faster when building a fat PVS (don't need to
copy as much) and can be used in multiple threads. Also, default visiblity
can be set, and the buffer size has its own macro.
The node struct was 72 bytes thus two cache line. Moving the pointer
into the brush model data block allows nodes to fit in a single cache
line (not that they're aligned yet, but that's next). It doesn't seem to
have made any difference to performance (at least in the vulkan
renderer), but it hasn't hurt, either, as the only place that needed the
parent pointer was R_MarkLeaves.
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.
This cleans up texture_t and possibly even improves locality of
reference when running through texture chains (not profiled, and not
actually the goal).
Since the hull depth needs to be set for the hull to be useful, it makes
sense to move the code into the same place that allocates new hulls (to me,
anyway).
The depth limits in the gl and glsl renderers and in the trace code really
bothered me, but then the fix hit me: at load-time, recurse the trees
normally and record the depth in the appropriate place. The node stacks can
then be allocated as necessary (I chose to add a paranoia buffer of 2, but
I expect the maximum depth will rarely be used).
All of the nastiness is hidden in bspfile.c (including the old bsp29
specific data types). However, the conversions between bsp29 and bsp2 are
implemented but not yet hooked up properly. This commit just gets the data
structures in place and the obvious changes necessary to the rest of the
engine to get it to compile, plus a few obvious "make it work" changes.
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.
