citra/src/audio_core/dsp_interface.cpp
Steveice10 178e602589
misc: Improve defaults for macOS and handling of missing audio backends. (#7273)
* misc: Improve backend defaults for macOS.

* audio_core: Improve handling of missing audio backends.
2023-12-22 11:38:06 -08:00

114 lines
3.9 KiB
C++

// Copyright 2017 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <cstddef>
#include "audio_core/dsp_interface.h"
#include "audio_core/sink.h"
#include "audio_core/sink_details.h"
#include "common/assert.h"
#include "common/settings.h"
#include "core/core.h"
#include "core/dumping/backend.h"
namespace AudioCore {
DspInterface::DspInterface(Core::System& system_) : system(system_) {}
DspInterface::~DspInterface() = default;
void DspInterface::SetSink(AudioCore::SinkType sink_type, std::string_view audio_device) {
// Dispose of the current sink first to avoid contention.
sink.reset();
sink = AudioCore::GetSinkDetails(sink_type).create_sink(audio_device);
sink->SetCallback(
[this](s16* buffer, std::size_t num_frames) { OutputCallback(buffer, num_frames); });
time_stretcher.SetOutputSampleRate(sink->GetNativeSampleRate());
}
Sink& DspInterface::GetSink() {
ASSERT(sink);
return *sink.get();
}
void DspInterface::EnableStretching(bool enable) {
enable_time_stretching = enable;
}
void DspInterface::OutputFrame(StereoFrame16 frame) {
if (!sink) {
return;
}
fifo.Push(frame.data(), frame.size());
auto video_dumper = system.GetVideoDumper();
if (video_dumper && video_dumper->IsDumping()) {
video_dumper->AddAudioFrame(std::move(frame));
}
}
void DspInterface::OutputSample(std::array<s16, 2> sample) {
if (!sink) {
return;
}
fifo.Push(&sample, 1);
auto video_dumper = system.GetVideoDumper();
if (video_dumper && video_dumper->IsDumping()) {
video_dumper->AddAudioSample(std::move(sample));
}
}
void DspInterface::OutputCallback(s16* buffer, std::size_t num_frames) {
// Determine if we should stretch based on the current emulation speed.
const auto perf_stats = system.GetLastPerfStats();
const auto should_stretch = enable_time_stretching && perf_stats.emulation_speed <= 95;
if (performing_time_stretching && !should_stretch) {
// If we just stopped stretching, flush the stretcher before returning to normal output.
flushing_time_stretcher = true;
}
performing_time_stretching = should_stretch;
std::size_t frames_written = 0;
if (performing_time_stretching) {
const std::vector<s16> in{fifo.Pop()};
const std::size_t num_in{in.size() / 2};
frames_written = time_stretcher.Process(in.data(), num_in, buffer, num_frames);
} else {
if (flushing_time_stretcher) {
time_stretcher.Flush();
frames_written = time_stretcher.Process(nullptr, 0, buffer, num_frames);
flushing_time_stretcher = false;
// Make sure any frames that did not fit are cleared from the time stretcher,
// so that they do not bleed into the next time the stretcher is enabled.
time_stretcher.Clear();
}
frames_written += fifo.Pop(buffer, num_frames - frames_written);
}
if (frames_written > 0) {
std::memcpy(&last_frame[0], buffer + 2 * (frames_written - 1), 2 * sizeof(s16));
}
// Hold last emitted frame; this prevents popping.
for (std::size_t i = frames_written; i < num_frames; i++) {
std::memcpy(buffer + 2 * i, &last_frame[0], 2 * sizeof(s16));
}
// Implementation of the hardware volume slider
// A cubic curve is used to approximate a linear change in human-perceived loudness
const float linear_volume = std::clamp(Settings::Volume(), 0.0f, 1.0f);
if (linear_volume != 1.0) {
const float volume_scale_factor = linear_volume * linear_volume * linear_volume;
for (std::size_t i = 0; i < num_frames; i++) {
buffer[i * 2 + 0] = static_cast<s16>(buffer[i * 2 + 0] * volume_scale_factor);
buffer[i * 2 + 1] = static_cast<s16>(buffer[i * 2 + 1] * volume_scale_factor);
}
}
}
} // namespace AudioCore