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.
r_screen isn't really the right place, but it gets the scene rendering
out of the low-level renderers and will make it easier to sort out
later, and hopefully easier to figure out a good design for vulkan.
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?)).
I'd been considering it for a while, but in the end, all the issues it
presented made me decide it wasn't worth merging and was never really
worth keeping: it was a neat proof of concept but of little actual use,
especially now everyone either has an OK GPU or would want to stick to
8-bit rendering anyway (sorry L-Havoc).
However, both it and my merge work are preserved in git history :)
I got tired of having to maintain two separate software renderers, but
didn't want to just nuke sw32, so its core changes are merged into sw.
Alias model rendering is broken, but I know exactly what's wrong and how
to fix it, just need to take care due to asm.
This takes care of the global variables to a point (there is still the
global struct shared between the non-vulkan renderers), but it also
takes care of glsl's points-only rendering.
After yesterday's crazy marathon editing all the particles files, and
starting to do another big change to them today, I realized that I
really do need to merge them down. All the actual spawning is now in the
client library (though particle insertion will need to be moved). GLSL
particle rendering is semi-broken in that it now does only points (until
I come up with a way to select between points and quads (probably a
context object, which I need anyway for Vulkan)).
This has the advantage of getting entity_t out of the particle system,
and much easier to read math. Also, it served as a nice test for my
particle physics shaders (implemented the ideas in C). There's a lot of
code that needs merging down: all but the actual drawing can be merged.
There's some weirdness with color ramps, but I'll look into that later.
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.
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.
I'm not certain despair actually meant for the break to be there. It
certainly would have sped up the game a bit but at the expense of proper
blood trails in the software renderers.
The seed is currently 0xdeadbeef, but I intend on fixing that soon. Now the
particle velocities and origins use fully independent bits (though a big
chunk is wasted right now).
This is a quick fix until I get a random number generator into QF.
Mingw's RAND_MAX is only 0x7fff and so the (((rnd >> 10) & 63) - 31.5) / 63.0
used for the z component of origin and velocity would never go positive.
For now, change the 10 to 9 (reusing another bit from Y). I plan on
implementing a full 32-bit PRNG in QF so we always have a reliable
generator.
