Thanks to the 3d frame buffer output being separate from the swap chain,
it's possible to have a different frame buffer size from the window
size, allowing for a smaller buffer and thus my laptop can cope (mostly)
with the vulkan renderer.
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.
Where too far is 1024 units as that is the maximum supported, or the
radius. The change to using unsigned for the distances meant the simple
checks missed the effective max dist going negative, thus leading to a
segfault.
I had debated putting the blending in the compose subpass or a separate
pass but went with the separate pass originally, but it turns out that
removing the separate pass gains 1-3% (5-15/545 fps in a timedemo of
demo1).
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.
Although it works as intended (tested via hacking), it's not hooked up
as the current frame buffer handling in r_screen is not readily
compatible with how vulkan output is handled. This will need some
thought to get working.
This splits up render pass creation so that the creation of the various
resources can be tailored to the needs of the actual render pass
sub-system. In addition, it gets window resizing mostly working (just
some problems with incorrect rendering).
It turns out the semaphore used for vkAcquireNextImageKHR may be left in
a signaled state for VK_ERROR_OUT_OF_DATE_KHR. While it seems to be
possible to clear the semaphore using an empty queue submission,
destroying and recreating the semaphore works well.
Still have problems with the frame buffer after window resize, though.
Swap chain acquisition is part of final output handling. However, as the
correct frame buffers are required for the render passes, the
acquisition needs to be performed during the preoutput render pass.
Window resize is still broken, but this is a big step towards fixing it.
This is the minimum maximum count for sampled images, and with layered
shadow maps (with a minimum of 2048 layers supported), that's really way
more than enough.
I guess nvidia gives a non-srgb format as the first in the list, but my
laptop gives an srgb format first, thus the unexpected difference in
rendering brightness. Hard-coding BGRA isn't any better, but it will do
for now.
Things are a bit of a mess with interdependence between sub-module
initialization and render pass initialization, and window resizing is
broken, but the main render pass rendering to an image that is then
post-processed (currently just blitted) is working. This will make it
possible to implement fisheye and water warp (and other effects, of
course).
When working, this will handle the output to the swap-chain images and
any final post-processing effects (gamma correction, screen scaling,
etc). However, currently the screen is just black because the image
for getting the main render pass output isn't hooked up yet.
Now each (high level) render pass can have its own frame buffer. The
current goal is to get the final output render pass to just transfer the
composed output to the swap chain image, potentially with scaling (my
laptop might be able to cope).
While the HUD and status bar don't cut out a lot of screen (normally),
they might start to make a difference when I get transparency working
properly. The main thing is this is a step towards pulling the 2d
rendering into another render pass so the main deferred pass is
world-only.
Using swizzles in an image view allows the same shader to be used with
different image "types" (eg, color vs coverage).
Of course, this needed to abandon QFV_CreateImageView, but that is
likely for the best.
It turns out that nearest filtering doesn't need any offsets to avoid
texel leaks so long as the screen isn't also offset. With this, the 2d
rendering looks good at any scale (minus the inherent blockiness).
