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.
