citra/src/audio_core/dsp_interface.cpp
Lioncash 90082268dc audio_core: Make g_sink_details internally linked
We can hide the direct array from external view and instead provide
functions to retrieve the necessary info. This has the benefit of
completely hiding the makeup of the SinkDetails structure from the rest
of the code.

Given that this makes the array hidden, we can also make the array
constexpr by altering the members slightly. This gets rid of several
static constructor calls related to std::vector and std::function.

Now we don't have heap allocations here that need to occur before the
program can even enter main(). It also has the benefit of saving a
little bit of heap space, but this doesn't matter too much, since the
savings in that regard are pretty tiny.
2018-12-16 02:44:04 +01:00

81 lines
2.7 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 "core/settings.h"
namespace AudioCore {
DspInterface::DspInterface() = default;
DspInterface::~DspInterface() = default;
void DspInterface::SetSink(const std::string& sink_id, const std::string& audio_device) {
sink = CreateSinkFromID(Settings::values.sink_id, Settings::values.audio_device_id);
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) {
if (perform_time_stretching == enable)
return;
if (!enable) {
flushing_time_stretcher = true;
}
perform_time_stretching = enable;
}
void DspInterface::OutputFrame(StereoFrame16& frame) {
if (!sink)
return;
fifo.Push(frame.data(), frame.size());
}
void DspInterface::OutputCallback(s16* buffer, std::size_t num_frames) {
std::size_t frames_written;
if (perform_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);
frames_written += fifo.Pop(buffer, num_frames - frames_written);
flushing_time_stretcher = false;
} else {
frames_written = fifo.Pop(buffer, num_frames);
}
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 with a dynamic range of 60 dB
const float linear_volume = std::clamp(Settings::values.volume, 0.0f, 1.0f);
if (linear_volume != 1.0) {
const float volume_scale_factor = std::exp(6.90775f * linear_volume) * 0.001f;
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