Mesen-X/Core/SoundMixer.cpp
2016-01-14 08:41:53 -05:00

104 lines
3 KiB
C++

#include "stdafx.h"
#include "SoundMixer.h"
#include "APU.h"
#include "CPU.h"
SoundMixer::SoundMixer()
{
_outputBuffer = new int16_t[APU::SamplesPerFrame];
_blipBuf = blip_new(APU::SamplesPerFrame);
InitializeLookupTables();
Reset();
}
SoundMixer::~SoundMixer()
{
delete[] _outputBuffer;
_outputBuffer = nullptr;
blip_delete(_blipBuf);
}
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, APU::SamplesPerFrame, 0);
IAudioDevice *audioDevice = APU::GetAudioDevice();
if(audioDevice) {
audioDevice->PlayBuffer(_outputBuffer, (uint32_t)(sampleCount * APU::BitsPerSample / 8));
}
}
void SoundMixer::SetNesModel(NesModel model)
{
blip_set_rates(_blipBuf, model == NesModel::NTSC ? CPU::ClockRateNtsc : CPU::ClockRatePal, APU::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, (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));
}