Replaces the ansnd-based backend (a third-party library with a custom
DSP ucode Dolphin's HLE audio emulation doesn't recognize, requiring
-a LLE as a workaround) with libogc's own asndlib - the standard,
HLE-supported audio API most GC/Wii homebrew already uses.
Also fixes three real bugs found while getting a large (41MB) WAV
asset actually playing on Dolphin:
- audiostreamdolphin.c previously buffered a stream's entire loop
segment into one allocation up front (inherited from the ansnd
design) - fine for a short test tone, but an out-of-memory crash for
a real multi-minute track on GameCube's 24MB (or even Wii's 88MB)
total RAM. Rewritten to stream bounded windows via ASND's real
double-buffer primitives (ASND_SetVoice + ASND_AddVoice, polled from
the main thread - never from an interrupt callback), matching how
Linux/PSP already work.
- ASND_TestVoiceBufferReady() returns SND_OK (0) when ready and
SND_BUSY (1) when not, in the actual toolchain fork
(extremscorner/libogc2) this project builds against - opposite of a
plain boolean. Treating the raw result as one meant a genuinely
ready voice's SND_OK read as false, silently skipping every
ASND_AddVoice() call forever after a stream's first buffered window.
- audioStreamPcmRead()'s 16-bit fast path read WAV's little-endian
sample bytes straight into the output buffer with no byte-swap -
correct by coincidence on every little-endian platform this engine
targets (Linux, PSP), but reversed every sample's bytes on
Dolphin/GameCube/Wii's big-endian PowerPC.
libmad is GPL-licensed (see audiostreammp3decodersw.h's own note from
the prior MP3 change); libogc's asndlib is under a permissive
BSD-style license, so this doesn't add another such dependency.
Co-Authored-By: Claude Sonnet 5 <[email protected]>
minimp3's sliding-window frame confirmation could spuriously discard real
frames near the tail of a not-yet-full window, losing ~5.5% of a real
VBR file's content even at a tuned 256KB window (~0.3% residual) -
audible as the whole track finishing early with stutters at each drop.
libmad's mad_stream/mad_frame/mad_synth API reports "need more data"
(MAD_ERROR_BUFLEN) and "genuinely bad data" separately rather than
overloading one return value, which was the actual ambiguity minimp3
couldn't resolve. Verified against the same real file with a 32KB window
(vs minimp3's 256KB): frame count and duration match the Xing header
exactly. Confirmed building for Linux, GameCube, and Wii (the latter two
via the project's real devkitPPC/libogc Docker toolchain) - libmad ships
inside libogc itself on Dolphin, no separate fetch needed there.
libmad is GPL-licensed, unlike the rest of this MIT project - a
deliberate tradeoff, noted at each site that pulls it in.
Co-Authored-By: Claude Sonnet 5 <[email protected]>
New ASSET_LOADER_TYPE_MP3 (hand-rolled MPEG-1/2/2.5 Layer III header
parser - no third-party dependency needed just for metadata, since PSP's
hardware path doesn't need one at all) plus a shared audiostreammp3.c
stream layer mirroring audiostreampcm.c's shape. Generalized the stream
dispatch (hoisted sampleRate/channels onto audiostream_t, added
audioStreamGetTotalFrames()/Seek()/Read()) so all three platform audio
backends keep working unchanged, just calling the generic names instead
of PCM-specific ones.
Two decoder backends behind one interface: PSP uses the real sceMp3
hardware decoder (firmware-offloaded, lazily initialized on first use);
Linux and Dolphin share one minimp3-based software decoder (public
domain, vendored via CMake FetchContent) - libogc's own MP3Player wraps
libmad (GPL) and drives its own output pipeline, not a fit for the
ansnd-based architecture already in place, so skipped in favor of the
shared minimp3 path.
Fixed three real bugs found via hardware/runtime testing along the way:
- LAME's Xing header counts its own placeholder frame in the declared
total, which made playback stall permanently one frame short of the
declared end (looked like "never loops") - fixed by subtracting it.
- sceMp3Decode() can return more PCM than one MPEG frame's worth in a
single call (PSP's pcmBuf is provisioned for 2x), overflowing the
shared per-frame decode buffer with no bound check - very intermittent
corruption/clicking on real hardware. Widened the buffer to the real
worst case and added an assertion.
- sceMp3ResetPlayPosition()'s exact internal reset semantics aren't
documented precisely enough to trust for looping - occasionally
disagreed with the fresh stream position fed right after, clicking at
the loop boundary about 1 in 3-4 loops. Rewind now fully tears down and
recreates the decoder instead, the same path already proven correct at
first Init. Also widened the PSP ring buffer to absorb that now-heavier
operation, capping each top-up call's own work so the bigger buffer
doesn't turn into one long blocking decode burst instead.
Co-Authored-By: Claude Sonnet 5 <[email protected]>
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.
EBOOT.PBP packing was a POST_BUILD step with no dependency on the asset
pak, so an assets-only rebuild could silently leave a stale dusk.dsk
embedded. cmake/targets/psp.cmake now repacks EBOOT.PBP via a properly
tracked custom command depending on the executable, PARAM.SFO, and
dusk.dsk (and correctly embeds Dusk.prx rather than the raw ELF when
BUILD_PRX is on).
Separately, libzip's zip_source_filep_create (lazy seeked FILE* reads)
proved unreliable on real PSP hardware, corrupting reads of the embedded
PSAR (first EINVAL, then zlib data errors) even though the packaged data
was verified byte-perfect. assetInitPBP now reads the whole PSAR into
memory once and uses zip_source_buffer_create instead. Confirmed working
on real hardware.
Co-Authored-By: Claude Sonnet 5 <[email protected]>
PSP checks memory-stick reachability via sceIoGetstat. GameCube gets two
devices (CARD_SLOTA/CARD_SLOTB), each mounted via CARD_Init/CARD_Mount and
checked for free space via CARD_GetDirectory/CARD_GetBlockCount. Wii picks
between three storage methods at compile time (DUSK_SAVE_WII_METHOD =
NAND/CARD/SD in wii.cmake, default NAND via ISFS) since real hardware
behavior for the default is unverified.
Also fixes two pre-existing bugs found while build/runtime-testing this
across PPSSPP and Dolphin: wrong libogc language macros in
systemGetLocaleDolphin, and a missing SYS_STDIO_Report(true) call that
silently swallowed all guest console output in Dolphin.
Co-Authored-By: Claude Sonnet 5 <[email protected]>