Mesen/Core/SoundMixer.cpp

133 lines
3.7 KiB
C++

#include "stdafx.h"
#include "SoundMixer.h"
#include "APU.h"
#include "CPU.h"
IAudioDevice* SoundMixer::AudioDevice = nullptr;
SoundMixer::SoundMixer()
{
_outputBuffer = new int16_t[SoundMixer::MaxSamplesPerFrame];
_blipBuf = blip_new(SoundMixer::MaxSamplesPerFrame);
_sampleRate = EmulationSettings::GetSampleRate();
InitializeLookupTables();
Reset();
}
SoundMixer::~SoundMixer()
{
delete[] _outputBuffer;
_outputBuffer = nullptr;
blip_delete(_blipBuf);
}
void SoundMixer::RegisterAudioDevice(IAudioDevice *audioDevice)
{
SoundMixer::AudioDevice = audioDevice;
}
void SoundMixer::StopAudio(bool clearBuffer)
{
if(SoundMixer::AudioDevice) {
if(clearBuffer) {
SoundMixer::AudioDevice->Stop();
} else {
SoundMixer::AudioDevice->Pause();
}
}
}
void SoundMixer::Reset()
{
_previousOutput = 0;
blip_clear(_blipBuf);
for(int i = 0; i < 5; i++) {
_volumes[0] = 0;
}
memset(_channelOutput, 0, sizeof(_channelOutput));
memset(_currentOutput, 0, sizeof(_currentOutput));
}
void SoundMixer::PlayAudioBuffer(uint32_t time)
{
EndFrame(time);
size_t sampleCount = blip_read_samples(_blipBuf, _outputBuffer, SoundMixer::MaxSamplesPerFrame, 0);
if(SoundMixer::AudioDevice) {
SoundMixer::AudioDevice->PlayBuffer(_outputBuffer, (uint32_t)(sampleCount * SoundMixer::BitsPerSample / 8), _sampleRate);
}
if(EmulationSettings::GetSampleRate() != _sampleRate) {
//Update sample rate for next frame if setting changed
_sampleRate = EmulationSettings::GetSampleRate();
UpdateRates();
}
}
void SoundMixer::SetNesModel(NesModel model)
{
_clockRate = model == NesModel::NTSC ? CPU::ClockRateNtsc : CPU::ClockRatePal;
UpdateRates();
}
void SoundMixer::UpdateRates()
{
blip_set_rates(_blipBuf, _clockRate, _sampleRate);
}
void SoundMixer::InitializeLookupTables()
{
for(int i = 0; i < 31; i++) {
double volume = 95.52 / (8128.0 / (double)i + 100.0);
_lupSquare[i] = (int16_t)(volume * 5000);
}
for(int i = 0; i < 203; i++) {
double volume = 163.67 / (24329.0 / (double)i + 100.0);
_lupTnd[i] = (int16_t)(volume * 5000);
}
}
int16_t SoundMixer::GetOutputVolume()
{
int16_t squareOutput = _lupSquare[(int)(_currentOutput[(int)AudioChannel::Square1] * _volumes[(int)AudioChannel::Square1] + _currentOutput[(int)AudioChannel::Square2] * _volumes[(int)AudioChannel::Square2])];
int16_t tndOutput = _lupTnd[(int)(3 * _currentOutput[(int)AudioChannel::Triangle] * _volumes[(int)AudioChannel::Triangle] + 2 * _currentOutput[(int)AudioChannel::Noise] * _volumes[(int)AudioChannel::Noise] + _currentOutput[(int)AudioChannel::DMC] * _volumes[(int)AudioChannel::DMC])];
return squareOutput + tndOutput;
}
void SoundMixer::AddDelta(AudioChannel channel, uint32_t time, int8_t delta)
{
_timestamps.push_back(time);
_channelOutput[(int)channel][time] += delta;
}
void SoundMixer::EndFrame(uint32_t time)
{
double masterVolume = EmulationSettings::GetMasterVolume();
sort(_timestamps.begin(), _timestamps.end());
_timestamps.erase(std::unique(_timestamps.begin(), _timestamps.end()), _timestamps.end());
for(size_t i = 0, len = _timestamps.size(); i < len; i++) {
uint32_t time = _timestamps[i];
_currentOutput[0] += _channelOutput[0][time];
_currentOutput[1] += _channelOutput[1][time];
_currentOutput[2] += _channelOutput[2][time];
_currentOutput[3] += _channelOutput[3][time];
_currentOutput[4] += _channelOutput[4][time];
int16_t currentOutput = GetOutputVolume();
blip_add_delta(_blipBuf, time, (int)((currentOutput - _previousOutput) * masterVolume));
_previousOutput = currentOutput;
}
blip_end_frame(_blipBuf, time);
//Reset everything
for(int i = 0; i < 5; i++) {
_volumes[i] = EmulationSettings::GetChannelVolume((AudioChannel)i);
}
_timestamps.clear();
memset(_channelOutput, 0, sizeof(_channelOutput));
}