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).
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.
And maybe a nano-optimization. Switching from (~side + 1) to (-side)
seems to give glsl a very tiny speed boost, but certainly doesn't hurt.
Looking at some assembly output for the three cases, the two hacks seem
to generate the same code as each other, but 3 instructions vs 6 for ?:.
While ?: is more generically robust, the hacks are tuned for the
knowledge side is either 0 or 1. The later xor might alter things, but
at least I now know that the hack (either version) is worthwhile.
This makes it much easier to see just what is being done to build a
polygon to be passed to the GPU, and it served as a test for the
lightmap st changes since Vulkan currently never used them.
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.
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.
Still work with gcc, of course, and I still need to fix them properly,
but now they're actually slightly easier to find as they all have vec_t
and FIXME on the same line.
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 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?)).
So far, in gl and glsl, but viewposition is much clearer than r_origin
(despite being the same thing), and modelorg is just confusing (I think
it's the view position relative to the current model).
GL still has its own functions for enabling and disabling fog while
rendering, but GLSL doesn't need such (thanks to the shaders), nor will
vulkan (and the software renderers don't support fog).
While there's currently only the one still, this will allow the entities
to be multiply queued for multi-pass rendering (eg, shadows). As the
avoidance of putting an entity in the same queue more than once relies
on the entity id, all entities now come from the scene (which is stored
in cl_world in the client code for nq and qw), thus the extensive
changes in the clients.
While I doubt the difference is all that significant, this should speed
up entity rendering because it cuts out a lot of branching, and
eliminates scanning the same list multiple times only to not do anything
for large chunks of the list.
Getting close to understanding (again) how it all works. I only just
barely understood when I got vulkan's renderer running, but I really
need to understand for when I modify things for shadows. The main thing
hurdle was tinst, but that was dealt with in the previous commit, and
now it's just sorting out the mess of elechains and elementss.
Its sole purpose was to pass the newly allocated instsurf when chaining
an instance model (ammo box, etc) surface, but using expresion
statements removes the need for such shenanigans, and even makes
msurface_t that little bit smaller (though a separate array would be
much better for cache coherence).
More importantly, the relevant code is actually easier to understand: I
spent way too long working out what tinst was for and why it was never
cleared.
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.
It now takes a context pointer (opaque data) that holds the buffers it
uses for the temporary strings. If the context pointer is null, a static
context is used (making those uses of va NOT thread-safe). Most calls to
va use the static context, but all such calls have been formatted
consistently so they are easy to find when it comes time to do a full
audit.
This makes tex_t more generally useable and probably more portable. The
goal was to be able to use tex_t with data that is in a separate chunk
of memory.
This cleans up texture_t and possibly even improves locality of
reference when running through texture chains (not profiled, and not
actually the goal).
The static variable meant that Fog_GetColor was not thread-safe (though
multiple calls in the one thread look to be ok for now). However, this
change takes it one step closer to being more generally usable.
Patch found in an old stash.
After messing with SIMD stuff for a little, I think I now understand why
the industry went with xyzw instead of the mathematical wxyz. Anyway, this
will make for less pain in the future (assuming I got everything).
Again, based on The OpenGL Shader Wrangler. The wrangling part is not used
yet, but the shader compiler has been modified to take the built up shader.
Just to keep things compiling, a wrapper has been temporarily created.
I'd missed a set of bit->lightnum conversions that resulting in lightnum
becoming much greater than 128 and thus trashing memory when the surface
was marked.
It was properly cleared after drawing water chains and sky chains, but I
had missed normal surfaces. It took the use of the same texture for both
normal surfaces and water surfaces to trigger the bug. Thanks go to Simon
'Sock' O'Callaghan and his In The Shadows mod.
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).
It turns out the expected orientation of the sky cube is exactly that of
Blender's default cube looked at from the front view (num-1) and the front
face being the nearest face. This put's Marcher's sun nicely in the view
when exiting the cave.
Rearrange the sky_suffix and sky_coords arrays and remove the sky_target
array such that the faces can be loaded using
GL_TEXTURE_CUBE_MAP_POSITIVE_X + i (apparently certain drivers break if
the faces aren't loaded in the correct order).
Also, the nomalization of the direction vector in the fragment isn't
necessary.
This reverts commit e170f4ee75.
It turns out I messed up something in the patch. I noticed the problem
while playing digs04.bsp: many sub-model surfaces, particularly those with
animated textures, were not being transformed correctly. As this patch did
not make a large performance difference, it's probably better to just
revert it. I might revisit it later.
