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Sound Mixer: Accurate volume control for each channel

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This commit is contained in:
Souryo 2016-06-01 19:38:31 -04:00
parent 1825fdcc1c
commit 7157c5801f
2 changed files with 10 additions and 18 deletions
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23
Core/SoundMixer.cpp
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@ -10,7 +10,6 @@ SoundMixer::SoundMixer()
_outputBuffer = new int16_t[SoundMixer::MaxSamplesPerFrame];
_blipBuf = blip_new(SoundMixer::MaxSamplesPerFrame);
_sampleRate = EmulationSettings::GetSampleRate();
InitializeLookupTables();
Reset();
}
@ -128,28 +127,24 @@ void SoundMixer::UpdateRates()
blip_set_rates(_blipBuf, _clockRate, _sampleRate);
}
void SoundMixer::InitializeLookupTables()
double SoundMixer::GetChannelOutput(AudioChannel channel)
{
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);
}
return _currentOutput[(int)channel] * _volumes[(int)channel];
}
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])];
double squareOutput = GetChannelOutput(AudioChannel::Square1) + GetChannelOutput(AudioChannel::Square2);
double tndOutput = 3 * GetChannelOutput(AudioChannel::Triangle) + 2 * GetChannelOutput(AudioChannel::Noise) + GetChannelOutput(AudioChannel::DMC);
uint16_t squareVolume = (uint16_t)(95.52 / (8128.0 / squareOutput + 100.0) * 5000);
uint16_t tndVolume = (uint16_t)(163.67 / (24329.0 / tndOutput + 100.0) * 5000);
int16_t expansionOutput = 0;
switch(_expansionAudioType) {
case AudioChannel::FDS: expansionOutput = (int16_t)(_currentOutput[ExpansionAudioIndex] * _volumes[ExpansionAudioIndex] * 20); break;
}
return squareOutput + tndOutput + expansionOutput;
return squareVolume + tndVolume + expansionOutput;
}
void SoundMixer::AddDelta(AudioChannel channel, uint32_t time, int8_t delta)

5
Core/SoundMixer.h
View file

@ -34,9 +34,6 @@ private:
int8_t _channelOutput[MaxChannelCount][CycleLength];
int8_t _currentOutput[MaxChannelCount];
int16_t _lupSquare[31];
int16_t _lupTnd[203];
blip_t* _blipBuf;
int16_t *_outputBuffer;
double _volumes[MaxChannelCount];
@ -44,7 +41,7 @@ private:
uint32_t _sampleRate;
uint32_t _clockRate;
void InitializeLookupTables();
double GetChannelOutput(AudioChannel channel);
int16_t GetOutputVolume();
void EndFrame(uint32_t time);