Re-implemented the NullSound back-end. Allows Dolphin to be used on hosts with no sound hardware. Emulates strict DSP timing in the DSP HLE plugin.

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@6329 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Core/AudioCommon/AudioCommon.vcproj

@@ -413,6 +413,14 @@
 		<Filter
 			Name="SoundStreams"
 			>
+			<File
+				RelativePath=".\Src\NullSoundStream.cpp"
+				>
+			</File>
+			<File
+				RelativePath=".\Src\NullSoundStream.h"
+				>
+			</File>
 			<File
 				RelativePath=".\Src\AOSoundStream.cpp"
 				>

Source/Core/AudioCommon/Src/AudioCommon.cpp

@@ -17,6 +17,7 @@
 
 #include "AudioCommon.h"
 #include "Mixer.h"
+#include "NullSoundStream.h"
 #include "DSoundStream.h"
 #include "AOSoundStream.h"
 #include "AlsaSoundStream.h"
@@ -37,6 +38,8 @@ namespace AudioCommon
 		std::string backend = ac_Config.sBackend;
 		if (backend == BACKEND_OPENAL           && OpenALStream::isValid()) 
 			soundStream = new OpenALStream(mixer);
+		else if (backend == BACKEND_NULLSOUND && NullSound::isValid()) 
+			soundStream = new NullSound(mixer, g_dspInitialize.hWnd);
 		else if (backend == BACKEND_DIRECTSOUND && DSound::isValid()) 
 			soundStream = new DSound(mixer, g_dspInitialize.hWnd);
 		else if (backend == BACKEND_AOSOUND     && AOSound::isValid()) 
@@ -91,6 +94,8 @@ namespace AudioCommon
 	{
 		std::vector<std::string> backends;
 
+		if (NullSound::isValid())  
+			backends.push_back(BACKEND_NULLSOUND);
 		if (DSound::isValid())  
 			backends.push_back(BACKEND_DIRECTSOUND);
 		if (OpenALStream::isValid())

Source/Core/AudioCommon/Src/AudioCommonConfig.h

@@ -22,6 +22,7 @@
 #include "IniFile.h"
 
 // Backend Types
+#define BACKEND_NULLSOUND	"No audio output"
 #define BACKEND_COREAUDIO   "CoreAudio"
 #define BACKEND_DIRECTSOUND "DSound"
 #define BACKEND_AOSOUND     "AOSound"

Source/Core/AudioCommon/Src/NullSoundStream.cpp

@@ -0,0 +1,48 @@
+// Copyright (C) 2003 Dolphin Project.
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, version 2.0.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License 2.0 for more details.
+
+// A copy of the GPL 2.0 should have been included with the program.
+// If not, see http://www.gnu.org/licenses/
+
+// Official SVN repository and contact information can be found at
+// http://code.google.com/p/dolphin-emu/
+
+#include "AudioCommon.h"
+#include "NullSoundStream.h"
+
+void NullSound::SoundLoop()
+{
+}
+
+bool NullSound::Start()
+{
+	return true;
+}
+
+void NullSound::SetVolume(int volume)
+{
+}
+
+void NullSound::Update()
+{
+	// This should equal AUDIO_DMA_PERIOD.  TODO: Fix after DSP merge
+	int numBytesToRender = 32000 * 4 / 32;
+	m_mixer->Mix(realtimeBuffer, numBytesToRender / 4);
+}
+
+void NullSound::Clear(bool mute)
+{
+	m_muted = mute;
+}
+
+void NullSound::Stop()
+{
+}

Source/Core/AudioCommon/Src/NullSoundStream.h

@@ -0,0 +1,48 @@
+// Copyright (C) 2003 Dolphin Project.
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, version 2.0.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License 2.0 for more details.
+
+// A copy of the GPL 2.0 should have been included with the program.
+// If not, see http://www.gnu.org/licenses/
+
+// Official SVN repository and contact information can be found at
+// http://code.google.com/p/dolphin-emu/
+
+#ifndef _NULLSOUNDSTREAM_H_
+#define _NULLSOUNDSTREAM_H_
+
+#include "SoundStream.h"
+#include "Thread.h"
+
+#define BUF_SIZE (48000 * 4 / 32)
+
+class NullSound : public SoundStream
+{
+    // playback position
+    short realtimeBuffer[BUF_SIZE / sizeof(short)];
+
+public:
+	NullSound(CMixer *mixer, void *hWnd = NULL)
+		: SoundStream(mixer)
+	{}
+
+    virtual ~NullSound() {}
+ 
+	virtual bool Start();
+    virtual void SoundLoop();
+	virtual void SetVolume(int volume);
+    virtual void Stop();
+	virtual void Clear(bool mute);
+    static bool isValid() { return true; }
+    virtual bool usesMixer() const { return true; }
+    virtual void Update();
+};
+
+#endif //_NULLSOUNDSTREAM_H_

Source/Core/AudioCommon/Src/SConscript

@@ -8,6 +8,7 @@ files = [
 	'WaveFile.cpp',
 	'Mixer.cpp',
 	'AudioCommon.cpp',
+	'NullSoundStream.cpp',
 	]
 
 if sys.platform == 'darwin':