From ed3beae3041a8d6dd819f51bd9579824f68fffd5 Mon Sep 17 00:00:00 2001
From: Alias Letterman <bearoso@gmail.com>
Date: Mon, 11 Feb 2019 18:45:45 -0600
Subject: [PATCH] win32: Add a WaveOut driver.

---
 win32/CWaveOut.cpp            | 176 ++++++++++++++++++++++++++++++++++
 win32/CWaveOut.h              |  43 +++++++++
 win32/snes9xw.vcxproj         |   2 +
 win32/snes9xw.vcxproj.filters |   6 ++
 4 files changed, 227 insertions(+)
 create mode 100644 win32/CWaveOut.cpp
 create mode 100644 win32/CWaveOut.h

diff --git a/win32/CWaveOut.cpp b/win32/CWaveOut.cpp
new file mode 100644
index 00000000..a2bc386a
--- /dev/null
+++ b/win32/CWaveOut.cpp
@@ -0,0 +1,176 @@
+/*****************************************************************************\
+     Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
+                This file is licensed under the Snes9x License.
+   For further information, consult the LICENSE file in the root directory.
+\*****************************************************************************/
+
+#include "CWaveOut.h"
+#include "../snes9x.h"
+#include "../apu/apu.h"
+#include "wsnes9x.h"
+
+CWaveOut::CWaveOut(void)
+{
+    hWaveOut = NULL;
+    initDone = false;
+}
+
+CWaveOut::~CWaveOut(void)
+{
+    DeInitSoundOutput();
+}
+
+void CALLBACK WaveCallback(HWAVEOUT hWave, UINT uMsg, DWORD_PTR dwUser, DWORD_PTR dw1, DWORD_PTR dw2)
+{
+    if (uMsg == WOM_DONE)
+    {
+        InterlockedDecrement(((volatile LONG *)dwUser));
+        SetEvent(GUI.SoundSyncEvent);
+    }
+}
+
+bool CWaveOut::SetupSound()
+{
+    WAVEFORMATEX wfx;
+    wfx.wFormatTag = WAVE_FORMAT_PCM;
+    wfx.nChannels = 2;
+    wfx.nSamplesPerSec = Settings.SoundPlaybackRate;
+    wfx.nBlockAlign = 2 * 2;
+    wfx.wBitsPerSample = 16;
+    wfx.nAvgBytesPerSec = wfx.nSamplesPerSec * wfx.nBlockAlign;
+    wfx.cbSize = 0;
+
+    waveOutOpen(&hWaveOut, WAVE_MAPPER, &wfx, (DWORD_PTR)WaveCallback, (DWORD_PTR)&bufferCount, CALLBACK_FUNCTION);
+
+    UINT32 blockTime = GUI.SoundBufferSize / blockCount;
+    singleBufferSamples = (Settings.SoundPlaybackRate * blockTime) / 1000;
+    singleBufferSamples *= 2;
+    singleBufferBytes = singleBufferSamples * 2;
+    sumBufferSize = singleBufferBytes * blockCount;
+    writeOffset = 0;
+    partialOffset = 0;
+
+    waveHeaders.resize(blockCount);
+    for (auto &w : waveHeaders)
+    {
+        w.lpData = (LPSTR)LocalAlloc(LMEM_FIXED, singleBufferBytes);
+        w.dwBufferLength = singleBufferBytes;
+        w.dwBytesRecorded = 0;
+        w.dwUser = 0;
+        w.dwFlags = 0;
+        w.dwLoops = 0;
+        w.lpNext = 0;
+        w.reserved = 0;
+        waveOutPrepareHeader(hWaveOut, &w, sizeof(WAVEHDR));
+    }
+    initDone = true;
+
+    return true;
+}
+
+void CWaveOut::SetVolume(double volume)
+{
+    waveOutSetVolume(hWaveOut, 0xffffffff);
+}
+
+void CWaveOut::BeginPlayback()
+{
+    waveOutRestart(hWaveOut);
+}
+
+bool CWaveOut::InitSoundOutput()
+{
+    return true;
+}
+
+void CWaveOut::DeInitSoundOutput()
+{
+    if (!initDone)
+        return;
+
+    waveOutReset(hWaveOut);
+
+    if (!waveHeaders.empty())
+    {
+        for (auto &w : waveHeaders)
+        {
+            waveOutUnprepareHeader(hWaveOut, &w, sizeof(WAVEHDR));
+            LocalFree(w.lpData);
+        }
+    }
+    waveHeaders.clear();
+
+    waveOutClose(hWaveOut);
+
+    initDone = false;
+}
+
+void CWaveOut::StopPlayback()
+{
+    waveOutPause(hWaveOut);
+}
+
+void CWaveOut::ProcessSound()
+{
+    int freeBytes = ((blockCount - bufferCount) * singleBufferBytes) - partialOffset;
+
+    if (Settings.DynamicRateControl)
+    {
+        S9xUpdateDynamicRate(freeBytes, sumBufferSize);
+    }
+
+    UINT32 availableSamples;
+
+    availableSamples = S9xGetSampleCount();
+
+    if (Settings.DynamicRateControl)
+    {
+        // Using rate control, we should always keep the emulator's sound buffers empty to
+        // maintain an accurate measurement.
+        if (availableSamples > (freeBytes >> 1))
+        {
+            S9xClearSamples();
+            return;
+        }
+    }
+
+    if (!initDone)
+        return;
+
+    if (partialOffset != 0) {
+        UINT32 samplesleftinblock = (singleBufferBytes - partialOffset) >> 1;
+        BYTE *offsetBuffer = (BYTE *)waveHeaders[writeOffset].lpData + partialOffset;
+
+        if (availableSamples <= samplesleftinblock)
+        {
+            S9xMixSamples(offsetBuffer, availableSamples);
+            partialOffset += availableSamples << 1;
+            availableSamples = 0;
+        }
+        else
+        {
+            S9xMixSamples(offsetBuffer, samplesleftinblock);
+            partialOffset = 0;
+            availableSamples -= samplesleftinblock;
+            waveOutWrite(hWaveOut, &waveHeaders[writeOffset], sizeof(WAVEHDR));
+            InterlockedIncrement(&bufferCount);
+            writeOffset++;
+            writeOffset %= bufferCount;
+        }
+    }
+
+    while (availableSamples >= singleBufferSamples && bufferCount < blockCount) {
+        BYTE *curBuffer = (BYTE *)waveHeaders[writeOffset].lpData;
+        S9xMixSamples(curBuffer, singleBufferSamples);
+        waveOutWrite(hWaveOut, &waveHeaders[writeOffset], sizeof(WAVEHDR));
+        InterlockedIncrement(&bufferCount);
+        writeOffset++;
+        writeOffset %= bufferCount;
+        availableSamples -= singleBufferSamples;
+    }
+
+    if (availableSamples > 0 && bufferCount < blockCount) {
+        S9xMixSamples((BYTE *)waveHeaders[writeOffset].lpData, availableSamples);
+        partialOffset = availableSamples << 1;
+    }
+}
\ No newline at end of file
diff --git a/win32/CWaveOut.h b/win32/CWaveOut.h
new file mode 100644
index 00000000..d2c7c26c
--- /dev/null
+++ b/win32/CWaveOut.h
@@ -0,0 +1,43 @@
+/*****************************************************************************\
+     Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
+                This file is licensed under the Snes9x License.
+   For further information, consult the LICENSE file in the root directory.
+\*****************************************************************************/
+
+#pragma once
+
+#include "../snes9x.h"
+#include <windows.h>
+#include "IS9xSoundOutput.h"
+#include <mmsystem.h>
+#include <vector>
+
+class CWaveOut : public IS9xSoundOutput
+{
+  private:
+    void BeginPlayback(void);
+    void StopPlayback(void);
+    void ProcessSound(void);
+
+    HWAVEOUT hWaveOut;
+    bool initDone;
+
+    volatile LONG bufferCount;
+    UINT32 sumBufferSize;
+    UINT32 singleBufferSamples;
+    UINT32 singleBufferBytes;
+    const UINT32 blockCount = 8;
+    UINT32 writeOffset;
+    UINT32 partialOffset;
+    std::vector<WAVEHDR> waveHeaders;
+  
+  public:
+    CWaveOut(void);
+    ~CWaveOut(void);
+
+    // Inherited from IS9xSoundOutput
+    bool InitSoundOutput(void);
+    void DeInitSoundOutput(void);
+    bool SetupSound(void);
+    void SetVolume(double volume);
+};
\ No newline at end of file
diff --git a/win32/snes9xw.vcxproj b/win32/snes9xw.vcxproj
index d8f873d8..3ed98cbc 100644
--- a/win32/snes9xw.vcxproj
+++ b/win32/snes9xw.vcxproj
@@ -439,6 +439,7 @@
     <ClInclude Include="cgMini.h" />
     <ClInclude Include="COpenGL.h" />
     <ClInclude Include="CShaderParamDlg.h" />
+    <ClInclude Include="CWaveOut.h" />
     <ClInclude Include="CXAudio2.h" />
     <ClInclude Include="dxerr.h" />
     <ClInclude Include="gl_core_3_1.h" />
@@ -582,6 +583,7 @@
     <ClCompile Include="CGLCG.cpp" />
     <ClCompile Include="COpenGL.cpp" />
     <ClCompile Include="CShaderParamDlg.cpp" />
+    <ClCompile Include="CWaveOut.cpp" />
     <ClCompile Include="CXAudio2.cpp" />
     <ClCompile Include="DumpAtEnd.cpp" />
     <ClCompile Include="dxerr.cpp" />
diff --git a/win32/snes9xw.vcxproj.filters b/win32/snes9xw.vcxproj.filters
index a88f1cf7..4a9d124b 100644
--- a/win32/snes9xw.vcxproj.filters
+++ b/win32/snes9xw.vcxproj.filters
@@ -291,6 +291,9 @@
     <ClInclude Include="..\shaders\SPIRV-Cross\spirv_parser.hpp">
       <Filter>Shaders</Filter>
     </ClInclude>
+    <ClInclude Include="CWaveOut.h">
+      <Filter>GUI\SoundDriver</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\bsx.cpp">
@@ -623,6 +626,9 @@
     <ClCompile Include="..\shaders\SPIRV-Cross\spirv_parser.cpp">
       <Filter>Shaders</Filter>
     </ClCompile>
+    <ClCompile Include="CWaveOut.cpp">
+      <Filter>GUI\SoundDriver</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <None Include="rsrc\nodrop.cur">