The escape was actually harmless as the buffers would not be read due to
the particle count being 0 (thus why the buffers were at the end of the
staging buffer: no space was allocated for them, only for the system
buffer, but their offsets were just past the system buffer). However,
the validation layers quite rightly did not like that. Thus, the two
buffers are pointed to the system buffer so all three descriptors are
always valid.
It's a bit flaky for particles, especially at higher frame rates, but
that's due to supporting only 64 overlapping pixels. A reasonable
solution is probably switching to a priority heap for the "sort" and
upping the limit.
This required making the texture set accessible to the vertex shader
(instead of using a dedicated palette set), which I don't particularly
like, but I don't feel like dealing with the texture code's hard-coded
use of the texture set. QF style particles need something mostly for the
smoke puffs as they expect a texture.
It doesn't want to work on my nvidia (or more recent sid?) and doesn't
seem to be necessary. The problem may be multiple event sets before the
first wait, but investigation can wait for now.
This is probably the biggest reason I had problems with particles not
updating correctly: the descriptors were generally point pointing to
where the data actually was in the staging buffer.
I don't yet know whether they actually work (not rendering yet), but the
system isn't locking up, and shutdown is clean, so at least resources
are handled correctly.
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 gets the pipelines loaded (and unloaded on shutdown). Probably the
easy part :P. Still need to sort out the command buffers,
synchronization, and particle generation (and probably a bunch else
that's not coming to mind).