Just head and tail are atomic, but it seems to work nicely (at least on
intel). I actually had more trouble with gcc (due to accidentally
testing lock-free with the wrong ring buffer... oops, but yup, gcc will
happily optimize your loop to spin really really fast). Also served as a
nice test for C11 threading.
This makes bsp traversal even more re-entrant (needed for shadows).
Everything needed for a "pass" is taken from bsp_pass_t (or indirectly
through bspctx_t (though that too might need some revising)).
Ambient lights are represented by a point at infinity and a zero
direction vector (spherical lights have a non-zero direction vector but
the cone angle is 360 degrees). This fixes what appeared to be mangled
light renderers (it was actually just an ambient light being treated as
a directional light (point at infinity, but non-zero direction vector).
There are some issues with the light renderers getting mangled, and only
the first light is even touched (just begin and end of render pass), but
this gets a lot of the framework into place.
Sounds odd, but it's part of the problem with calling two different
things with essentially the same name. The "high level" render pass in
question may be a compute pass, or a complex series of (Vulkan) render
passes and so won't create a Vulkan render pass for the "high level"
render pass (I do need to come up with a better name for it).
I really don't remember why I made it separate, though it may have been
to do with r_ent_queue. However, putting it together with the rest is
needed for the "render pass" rework.
It now lives in vulkan_renderpass.c and takes most of its parameters
from plist configs (just the name (which is used to find the config),
output spec, and draw function from C). Even the debug colors and names
are taken from the config.
QFV_CreateRenderPass is no longer used, and QFV_CreateFramebuffer hasn't
been used for a long time. The C file is still there for now but is
basically empty.
The real reason for the delay in implementing support for pNext is I
didn't know how to approach it at the time, but with the experience I've
gained using and modifying vkparse, the solution turned out to be fairly
simple. This allows for the use of various extensions (eg, multiview,
which was used for testing, though none of the hookup is in this
commit). No checking is done on the struct type being valid other than
it must be of a chainable type (ie, have its own pNext).
The software renderer uses Bresenham's line slice algorithm as presented
by Michael Abrash in his Graphics Programming Black Book Special Edition
with the serial numbers filed off (as such, more just so *I* can read
the code easily), along with the Chen-Sutherland line clipping
algorithm. The other renderers were more or less trivial in comparison.
Enabled by 'developer lighting'. It was good for confirming that the
lights in ad_e1m1 (Doom Hangar 16) were actually being output (over 600
of them sometimes, ouch). Turned out to be the color scale ambiguity.
The pitch cvars are taken from quakespasm because I ran into a button I
couldn't shoot with the 80 degree limit, but I figured I'd add roll
limits while I was at it.
Surfaces marked with SURF_DRAWALPHA but not SURF_DRAWTURB are put in a
separate queue for the water shader and run with a turb scale of 0.
Also, entities with colormod alpha < 1 are marked to go in the same
queue as SURF_DRAWALPHA surfaces (ie, no SURF_DRAWTURB unless the
model's texture indicated such).
Textures whose names start with a { are meant to be rendered with
transparency. Surfaces using those textures are marked with
SURF_DRAWALPHA.
Unfortunately, the mip levels of ad_tears' transparent textures use the
wrong color so only the highest LOD works properly, but those textures
are meant to be loaded from external files anyway, it seems.
PR_Debug_ValueString prints the value at the given offset using the
provided type to format the string. The formatted string is appended to
the provided dstring.
For whatever reason, building under MXE (for windows) causes FLAC to try
to use dll import references, but setting FLAC__NO_DLL before including
FLAC/export.h fixes the issue.
-describe is sent to the object, and the returned string passed back.
There is a worry about the lifetime of the returned string as there's
currently no way of both ensuring it doesn't get freed prematurely and
ensuring it does eventually get freed.
If no handler has been registered, then the corresponding parameter is
printed as a pointer but with surrounding brackets (eg, [0xfc48]). This
will allow the ruamoko runtime to implement object printing.
Due to the mis-initialization of the union used to parse the color
vector, the intensity was incorrectly set to zero and thus the light
dropped, meaning that all lights in ad_tears were lost.
The extend instruction is for loading narrower data types into wider
data types, eg, single element into 2, 3, or 4 element types, with a
small set of extension schemes: 0, 1, -1, copy (for 1->any and 2 -> 4).
Possibly most importantly, it works with unaligned data.
Progress towards #30
Most were pretty easy and fairly logical, but gib's regex was a bit of a
pain until I figured out the real problem was the conditional
assignments.
However, libs/gamecode/test/test-conv4 fails when optimizing due to gcc
using vcvttps2dq (which is nice, actually) for vector forms, but not the
single equivalent other times. I haven't decided what to do with the
test (I might abandon it as it does seem to be UD).
This gets ambient sounds (in particular, water and sky) working again
for quakeworld after the recent sound changes, and again for nq after I
don't know how long.
Because the calculation didn't take the hunk header size (which is not
included in the hunk size) into account, the conversion to MB was one
short and thus the rounding up to the next 8 MB boundary was giving the
current total hunk size (ie, the already given size). Most confusing to
a user ("But I already asked for 128MB!").
It turns out that copying just "unknown" is a significant performance
hit when doing over 100M allocations. Making Hunk_RawAlloc the core and
initializing the name field with a single 0 shaved about a second off
`qfvis gmsp3v2.bsp` (from about 39s to about 38s).
My reason for using Hunk_HighAlloc for allocating cache blocks was to
lock them down so they were safe for the sound mixer to access when
running in a real-time thread. However, I had never tested under tight
memory constraints, which proved that the design (or maybe just
implementation) just wasn't robust. However, now that sounds are loaded
into a completely separate region, it's safe to put the cache back to
its original behaviour (still with 64-byte alignment and such, of
course). This will even allow the high hunk to be used again, though it
effectively was anyway with Hunk_TempAlloc.
I never liked "cache" as a name because it said where the sound was
stored rather than how it was loaded/played, but "stream" is ok, since
that's pretty much spot on. I'm not sure "block" is the best, but it at
least makes sense because the sounds are loaded as a single block (as
opposed to being streamed). An now, neither use the cache system.
Nuclear powered audio ;)
More seriously, use _Atomic on a few fields that very obviously need it.
That is, channel's buffer pointer (used to signal to the mixer that the
channel is ready for use) and "flow control" flags (stop, done and
pause), and head and tail in the buffer itself. Since QF has been
working without _Atomic (admittedly, thanks to luck and x86's strong
memory model), this should do until proven otherwise. I imagine getting
stream reading out of the RT thread will highlight any issues.
Turned out the channels simply weren't being freed by SND_ScanChannels
when they should have been (probably a good thing, too, as it wasn't
being told to wait for the mixer).
Care needs to be taken when freeing channels as doing so while an
asynchronous mixer is using them is unlikely to end well. However,
whether the mixer is asynchronous depends on the output driver. This
lets the driver inform the rest of the system that the output and mixer
are running asynchronously.