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.
SYS_dev is a holdover from when we had only the one flag and is not
meant to be used for tests (I seem to remember mentioning an audit was
necessary, but obviously forgotten). One step at a time, I guess :)
This improves the locality of reference when mixing and removes the
proxy sfx for streamed sounds.
The buffer for streamed sounds is allocated when the stream is opened
(since streamed sounds can't share buffers), and freed when the stream
is closed.
For block sounds, the buffer is reference counted (with the sfx holding
one reference, so currently block buffers never get freed), with their
reference count getting incremented on open and decremented on close.
That the reference counts get to 1 has been confirmed, so all that
should be needed is proper destruction of the sfx instances.
Still need to sort out just why channels leak across level changes.
Getting the tag is possibly useful in general and definitely in
debugging. Setting, I'm not so sure as it should be done when allocated,
but that's not always possible.
Also, correct the return type of z_block_size, though it affected only
Z_Print. While an allocation larger than 4GB is... big for zone, the
blocks do support it, so printing should too.
They're currently treated as non-fatal, those sounds just won't ever
play. This allows ad_tears to at least load with only 32MB of locked
memory (it needs somewhere between 64 and 96).
Since Ruamoko got vector types, zone's 8-byte alignment was no longer
sufficient due to hardware-enforced alignment requirements of the
underlying vector operations.
Fixes#28.
And use it for Ruamoko object reference counts.
I need reference counts for dealing with block sound buffers since they
can be shared by many channels. I figured I take care of Ruamoko's
reference count location at the same time.
Fixes#27.
Sounds no longer use the cache, which is good for multi-threaded, but a
pain for memory management: the buffers are shared between channels that
play back the sounds, but when the sounds were cached, they were
automagically (thus problematically) freed when the space was needed.
That no longer happens, so they leak. I think the solution is to use
reference counting and retain/release in sfx->open() and sfx->close().
Streams are the easy one as they were never in the cache. As a side
effect, sfxstream_t is much smaller as it no longer has the buffer
embedded in the struct.
SND_AllocChannel is a little too aggressive in freeing channels that
have finished as the channel may be externally owned (eg, by cd_file).
Get bgm looping working again.
More shrinkage. It turned out the mixer uses the phase fields, so they
couldn't be removed, but even at 192kHz, +/- 127 samples produces
sufficient phase separation for a 21cm head (which is, actually, pretty
big: mine is about 15cm across), but that change can come later.
The ambient sound loading has been removed from snd_channels because 1)
it doesn't work for nq, 2) it should never have been there in the first
place (it belongs in the client, but that needs some more API).
This is part of a process to shrink channel_t so it doesn't waste locked
memory when it gets moved there. Eventually, only the fields the mixer
needs will be in channel_t itself: those needed for spacialization will
be moved into a separate array.
In the process, I found that channels leak across level changes, but
this appears to be due to the cached sounds being removed during loading
and the mixer never marking them as done (it sees the null sfx pointer
and assumes the channel was never in use). Having the mixer mark the
channel as done seems to fix the leak, but cause a free channel list
overflow. Rather than fight with that, I'll leave the leak for now and
fix it at its root cause: the management of the sound samples
themselves.
Sys_DoubleTime starts at 4Gs in order to keep its precision fixed for a
nice long time (about 120 years, iirc).
This fixes an instant watchdog trigger when first starting up in
testsound. I'm not sure why it didn't happen with nq, but I guess that
doesn't really matter
The scaling up of the volumes when setting a channel's volume bothered
me. The biggest issue being it hasn't been necessary for over a decade
since the conversion to a float-mixer. Now the volume and attenuation
scaling from protocol bytes is entirely in the client's hands.
This does mean that the gl and sw renderers can no longer call
S_ExtraUpdate, but really, they shouldn't be anyway. And I seem to
remember it not really helping (been way too long since quake ran that
slowly for me).
sfx_t is now private, and cd_file no longer accesses channel_t's
internals. This is necessary for hiding the code needed to make mixing
and channel management *properly* lock-free (I've been getting away with
murder thanks to x86's strong memory model and just plain luck with
gcc).
The tests fail as they exercise how the cache *SHOULD* work rather than
how it does now.
The tests do currently pass for the pending work I've done on the cache
system, but while working on it, I remembered why I reworked cache
allocation...
The essential problem is that sounds are loaded into the cache, which is
fine for synchronous output targets, but has proven to be a minefield
for asynchronous output targets (JACK, ALSA).
The reason for the minefield is the hunk takes priority over the cache,
and is free to move cache blocks around, and *even dispose of them
entirely* in order to satisfy memory allocations from either end of the
hunk. Doing this in an entirely single-threaded process (as DOS Quake
was) is perfectly safe, as the users of the cache just reload the
pointer each time, and bail if it's null (meaning the block has been
freed), or even cause the data to be reloaded if possible (I'm a little
fuzzy on the details for that as I didn't write that code). However, in
multi-threaded code, especially real-time (JACK, possibly ALSA), it's a
recipe for disaster. The 4cab5b90e6 commit was a (mostly) successful
attempt to mitigate the problem by allocating the cache blocks from the
high-hunk (thus minimizing any movement caused by low-hunk allocations),
it resulted in cache allocates and regular high-hunk allocations somehow
getting intertwined: while investigating just how much memory ad_tears
needs (somewhere between 192MB and 256MB), I got "trashed sentinel"
errors and upon investigation, I found what looks very suspiciously like
audio data written across a hunk control block.
I've decided that the cache allocation *algorithm* should be reverted to
how it was originally designed by Id (details will remain "modern"), but
while working on the tests, I remembered why I had done the changes in
the first place (above story). Thus the work on reverting the cache
allocation can't go in until I get sound memory management independent
of the cache. The tests are going in now so I have a constant reminder :)
And make Sys_MaskPrintf take the developer enum rather than just a raw
int.
It was actually getting some nasty hunk corruption errors when under
memory pressure that made it clear the sound system needs some work.
I always wanted it there, there were dependency issues at the time. I
guess they got cleaned up for the most part since then (other than
cd_file, but it's on my hit-list).
I had been trimming for the solid leaf, but not the empty leafs. I had
assumed the vis tool would trim the bits, but it seems to not be
reliable (though it could be a bug in qfvis, I think the map in question
is one of my test maps).
The texture animation data is compacted into a small struct for each
texture, resulting in much less data access when animating the texture.
More importantly, no looping over the list of frames. I plan on
migrating this to at least the other hardware renderers.
I found a test map with no texture data. Even after fixing the bsp
loader, vulkan didn't like it. Now vulkan is happy. The "Missing" text
is full-bright magenta on a dim grey background so it should be visible
in any lighting conditions.
More host cleanup. The client now processes input itself, as does the
server, but only if running a dedicated server. The server no longer
blocks sound when loading a map as it shouldn't know anything about
sound. This will probably need something done in the client, but moving
the server into a separate thread will have that effect anyway.
Conflagrant Rodent has a sub-model with 0 faces (double bit error?)
causing simply counting faces to get out of sync with actual model
starts thus breaking *all* brush models that come after it (including
other maps). Thus be a little less lazy in figuring out model start
faces.
The models are broken up into N sub-(sub-)models, one for each texture,
but all faces using the same texture are drawn as an instance, making
for both reduced draw calls and reduced index buffer use (and thus,
hopefully, reduced bandwidth). While texture animations are broken, this
does mark a significant milestone towards implementing shadows as it
should now be possible to use multiple threads (with multiple index and
entid buffers) to render the depth buffers for all the lights.
This allows the use of an entity id to index into the entity data and
fetch the transform and colormod data in the vertex shader, thus making
instanced rendering possible. Non-world brush entities are still not
rendered, but the world entity is using both the entity data buffer and
entid buffer.
Sub-models and instance models need an instance data buffer, but this
gets the basics working (and the proof of concept). Using arrays like
this actually simplified a lot of the code, and will make it easy to get
transparency without turbulence (just another queue).
The gl water warp ones have been useless since very early on due to not
doing water warp in gl (vertex warping just didn't work well), and the
recent water warp implementation doesn't need those hacks. The rest of
the removed flags just aren't needed for anything. SURF_DRAWNOALPHA
might get renamed, but should be useful for translucent bsp surfaces
(eg, vines in ad_tears).
One more step towards BSP thread-safety. This one brought with it a very
noticeable speed boost (ie, not lost in the noise) thanks to the face
visframes being in tightly packed groups instead of 128 bytes apart,
though the sw render's boost is lost in the noise (but it's very
fill-rate limited).
This is next critical step to making BSP rendering thread-safe.
visframe was replaced with cluster (not used yet) in anticipation of BSP
cluster reconstruction (which will be necessary for dealing with large
maps like ad_tears).
Bill Currie