nCine::Ps3AudioDevice class
#include <nCine/Audio/Backends/PS3/Ps3AudioDevice.h>

PlayStation 3 implementation of IAudioDevice on top of PSL1GHT's libaudio.

The console has no mixer to talk to. Where the Dreamcast's AICA is a 64-voice wavetable part with its own sound RAM and the Wii's DSP runs libogc's ASND, lv2 hands a title exactly one thing: a ring of 256-sample blocks of interleaved 32-bit float samples, which the audio hardware scans out verbatim. Everything above that - mixing, resampling, panning, looping, stream queues - is this class, on the PPE.

Two consequences shape the whole design.**

Everything is mixed by hand into one output.* There is no per-source volume or pitch register to program, so setSourceGain() and friends only record a value that MixInto() applies while it walks the sources. That also means a source costs CPU only while it is audible, which is why MaxSources can be generous.

There is no mixer thread.* PSL1GHT ships no pthreads (see the NCINE_WITH_THREADS arm in ncine_options.cmake), so the ring cannot be topped up from a callback the way every other backend does it - it is filled from updatePlayers(), once per frame, on the main thread. That works because the ring is deliberately long: BlockCount blocks of 256 samples at 48 kHz is about 85 ms of audio, so a frame may take five times its 16.6 ms budget before the ring runs dry. What it costs is latency, which for this game is not a meaningful trade.

Resampling is linear interpolation from the buffer's own rate to the port's 48 kHz. The PPE has the headroom for it at these voice counts, and the alternative - resampling every asset offline to one rate - would trade quality for memory the console does not need to save.

Base classes

class AudioDeviceBase: Backend-independent part of an audio device.

Constructors, destructors, conversion operators

Ps3AudioDevice()
~Ps3AudioDevice() override

Public functions

auto isValid() const -> bool override: Returns true if the device was initialized successfully.
auto name() const -> const char* override: Returns the name of the underlying device.
void setGain(float gain) override: Sets the listener gain (master volume).
void updateListener(const Vector3f& position, const Vector3f& velocity) override: Updates the position and velocity of the listener.
auto nativeFrequency() -> std::int32_t override: Returns the native sample rate of the device.
auto registerPlayer(IAudioPlayer* player) -> std::uint32_t override: Registers a player so it receives state and buffer queue updates, returning its source id.
void updatePlayers() override: Updates the state of every registered player, including the buffer queue of stream players.
auto createBuffer(BufferUsage usage) -> std::uint32_t override: Creates an empty backend buffer, returning its id or 0 on failure.
void deleteBuffer(std::uint32_t bufferId) override: Destroys a buffer previously returned by createBuffer().
auto uploadBuffer(std::uint32_t bufferId, BufferFormat format, const void* data, std::int32_t size, std::int32_t frequency) -> bool override: Replaces the contents of a buffer with the specified samples.
void setSourceBuffer(std::uint32_t sourceId, std::uint32_t bufferId) override: Attaches a buffer to a source for non-streamed playback, 0 detaches the current one.
void setSourceGain(std::uint32_t sourceId, float gain) override: Sets the gain of a source.
void setSourcePitch(std::uint32_t sourceId, float pitch) override: Sets the pitch of a source, as a multiplier of its natural playback rate.
void setSourceLooping(std::uint32_t sourceId, bool looping) override: Sets whether a source repeats its attached buffer.
void setSourceRelative(std::uint32_t sourceId, bool relative) override: Sets whether the position of a source is relative to the listener.
void setSourcePosition(std::uint32_t sourceId, const Vector3f& position) override: Sets the position of a source, in physical units.
void setSourceLowPass(std::uint32_t sourceId, float value) override: Sets the low-pass amount of a source, 1.0f disables the filter.
auto sourceSampleOffset(std::uint32_t sourceId) -> std::int32_t override: Returns the playback position of a source in samples.
void setSourceSampleOffset(std::uint32_t sourceId, std::int32_t offset) override: Sets the playback position of a source in samples.
void playSource(std::uint32_t sourceId) override: Starts or resumes a source.
void pauseSource(std::uint32_t sourceId) override: Pauses a source at its current position.
void stopSource(std::uint32_t sourceId) override: Stops a source.
auto isSourcePlaying(std::uint32_t sourceId) -> bool override: Returns true if a source is still producing sound.
void queueBuffer(std::uint32_t sourceId, std::uint32_t bufferId) override: Appends a buffer to the streaming queue of a source.
auto numProcessedBuffers(std::uint32_t sourceId) -> std::int32_t override: Returns the number of queued buffers a source has finished playing.
void unqueueBuffers(std::uint32_t sourceId, std::int32_t count, std::uint32_t* bufferIds) override: Removes the specified number of played buffers from the front of the queue.
void suspendDevice() override: Suspends the audio device.
void resumeDevice() override: Resumes the audio device.

Function documentation

void nCine::Ps3AudioDevice::unqueueBuffers(std::uint32_t sourceId, std::int32_t count, std::uint32_t* bufferIds) override

Removes the specified number of played buffers from the front of the queue.