- Extract audioStreamGetPanFactors() into the shared layer, replacing
identical pan-to-LR math duplicated in the PSP and Dolphin backends
(and dropping a dead clamp - directionality's int8_t range already
guarantees pan stays in [-1, 1]).
- Implement audioStreamSetPosition() for real (was previously a no-op
that computed a value and threw it away) and add
audioStreamSetLoopPoints() to actually drive loopStart/loopTo, which
were previously dead fields with no setter at all. Both are threaded
through all three platform backends:
- PSP: the feeder thread now bounds each pass by the loop segment
and wraps to loopTo instead of always frame 0, while still filling
hardware chunks gaplessly.
- Dolphin: loopTo/loopStart map directly onto ansnd's existing
loop_start_offset/loop_end_offset, and startFrame onto start_offset.
- Linux: Buffer() now queues only the current segment, clearing the
SDL queue on an explicit seek but preserving the existing
overlap-based gapless loop restart otherwise.
- Linux: skip the mix scratch-buffer entirely at full volume, queuing
stream->data directly instead of allocating/zeroing/copying into one
every buffer call for no reason.
Verified no regression in the default (no seek, no loop points) case on
Linux/PPSSPP/Dolphin (-a LLE), and verified seek + loop-region behavior
manually via a temporary engine.c smoke-test tweak (reverted) showing
the expected faster loop cadence and seek-then-loop sequencing.
ansnd_configure_pcm_voice requires frame_data_ptr to be a physical
address - it rejects cached virtual pointers (0x8xxxxxxx) as
ANSND_ERROR_INVALID_MEMORY. Convert via MEM_VIRTUAL_TO_PHYSICAL and flush
the CPU cache first so the DSP's DMA read sees what was actually written.
Root-caused by disassembling libansnd's ansnd_configure_pcm_voice (no
source available, only the static lib) and confirming via a temporary
debug print that frame_data_ptr's top bit being set was what tripped the
check. Confirmed fixed by running the Wii DOL build in Dolphin under -a
LLE - voice configure/start now succeed with no errors.
Root cause of the crackle (confirmed on real PSP hardware): the
persistent feeder thread called stream->onLoop directly in the middle
of its tight chunk-feeding loop. onLoop can do arbitrary work (the
test callback does consolePrint, which locks a mutex, moves the
console history buffer, and fflushes stdout) - if that takes anywhere
close to one chunk's playback time (~23ms), the next chunk isn't
ready and the hardware channel starves. Audio callbacks must never be
invoked directly from a real-time audio thread.
Fixed generically: audiostream_t gains loopCount (incremented by
platform code from whatever context it runs in) and lastLoopCount
(main-thread-only bookkeeping). audioStreamUpdate() detects the
change and fires onLoop safely from the main thread, regardless of
which thread/interrupt actually noticed the loop. PSP's feeder thread
now increments the counter instead of calling onLoop inline.
Also eliminated the ~21.7ms of real silence padding baked into every
PSP loop pass (found while chasing the timing gap that preceded the
crackle fix): the final chunk's padding is now filled with the start
of the next loop instead of zero, avoiding sceAudioSetChannelDataLen
(the likely real cause of an earlier, separate click) while keeping
every output call the same constant size. Loop period measured via
PPSSPP is now ~1.000-1.002s for a 1.000s tone, down from a consistent
~1.02-1.03s before.
The PSP feeder thread is also now persistent for the stream's whole
lifetime (created once in Init, idles between plays) rather than
respawned via threadStartRequest on every single loop restart - real,
avoidable OS thread creation overhead that was contributing to the
gap before the padding was identified as the dominant cause.
Brought Dolphin in line architecturally rather than mirroring PSP/
Linux's restart-and-detect approach: ansnd_pcm_voice_config_t has
native loop_start_offset/loop_end_offset fields, so a looping Dolphin
voice loops entirely in DSP hardware with zero host involvement at
the loop boundary - no restart latency to create a gap in the first
place. Trade-off, clearly documented in code: onLoop never fires for
Dolphin this way (no ANSND_VOICE_STATE for "wrapped") and it requires
cleanly-authored loop content (no per-wrap fade like PSP's, matching
the same assumption). Compiles cleanly for both gamecube and wii;
not yet verified on real hardware.
Confirmed on real PSP hardware: no more gap, crackle fix pending
final hardware confirmation.
Allocates an ansnd voice per stream and configures/starts it in
single-buffer mode (no continuous re-feed needed yet, matching the
PSP/Linux single-shot approach). Real linear panning from
directionality via left/right voice volume. ansnd has no polling API
for voice state, so finish detection uses a voice_callback (fired
from ansnd's own audio DMA interrupt, not the main thread) that sets
a flag audioStreamDolphinIsFinished() reads.
Links libansnd (new for this project) and wires duskdolphin/audio
into the CMake build for the first time.
Verified via the dusk-dolphin toolchain: both GameCube and Wii
targets compile and link cleanly. Runtime verification in headless
Dolphin was inconclusive - confirmed via an A/B test against a
pre-audio baseline build that a pre-existing MMIO flood (unrelated
to this change, reproduces identically with zero audio code present)
keeps the harness from reaching the game's own steady state before
timing out.
Cross-platform audiostream/audio API with per-platform hooks for
PSP/Dolphin/Linux. Linux is fully wired end-to-end through SDL2
(device open, volume-mixed queueing, finish detection via
SDL_GetQueuedAudioSize) and verified playing a generated test tone
in engine.c. PSP and Dolphin hooks are stubbed for now.
YourWishes