From 1dc65e0988712efe42d2af7328ca284dc49d5c87 Mon Sep 17 00:00:00 2001
From: Souryo <mesenemu@gmail.com>
Date: Thu, 14 Jan 2016 08:41:53 -0500
Subject: [PATCH] Added missing file from previous commit

---
 Core/SoundMixer.cpp | 104 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 Core/SoundMixer.cpp

diff --git a/Core/SoundMixer.cpp b/Core/SoundMixer.cpp
new file mode 100644
index 00000000..d9e3a66a
--- /dev/null
+++ b/Core/SoundMixer.cpp
@@ -0,0 +1,104 @@
+#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));
+}