Have the AudioUnit callback drive the internal mixer directly instead

of going through an intermediate thread and buffer. This seems to be
how Core Audio is meant to be used, although I still haven't read the
manual.

Indeed, sound on OS X works perfectly now.


git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@5555 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Core/AudioCommon/Src/CoreAudioSoundStream.cpp

@@ -17,33 +17,23 @@
 
 #include "CoreAudioSoundStream.h"
 
-volatile unsigned int numBytesToRender;				/* XXX */
-
-typedef struct internal
-{
-	AudioUnit audioUnit;
-	short realtimeBuffer[1024];				/* XXX */
-};
-
 OSStatus callback(void *inRefCon, AudioUnitRenderActionFlags *ioActionFlags,
 			const AudioTimeStamp *inTimeStamp, UInt32 inBusNumber,
 			UInt32 inNumberFrames, AudioBufferList *ioData)
 {
-	internal *soundStruct = (internal *)inRefCon;
+	for (UInt32 i = 0; i < ioData->mNumberBuffers; i++)
-
-	for (int i=0; i < (int)ioData->mNumberBuffers; i++)
 	{
-		memcpy(ioData->mBuffers[i].mData, &soundStruct->realtimeBuffer,
+		((CoreAudioSound *)inRefCon)-> \
+			RenderSamples(ioData->mBuffers[i].mData,
 					ioData->mBuffers[i].mDataByteSize);
 	}
 
-	numBytesToRender = ioData->mBuffers[0].mDataByteSize;	/* XXX */
+	return noErr;
-	return 0;
 }
 
-void CoreAudioSound::SoundLoop()
+void CoreAudioSound::RenderSamples(void *target, UInt32 size)
 {
-	CoreAudioInit();
+	m_mixer->Mix((short *)target, size / 4);
 }
 
 CoreAudioSound::CoreAudioSound(CMixer *mixer) : SoundStream(mixer)
@@ -54,19 +44,12 @@ CoreAudioSound::~CoreAudioSound()
 {
 }
 
-bool CoreAudioSound::CoreAudioInit()
+bool CoreAudioSound::Start()
 {
-	ComponentDescription desc;
 	OSStatus err;
 	UInt32 enableIO;
 	AURenderCallbackStruct callback_struct;
 	AudioStreamBasicDescription format;
-	UInt32 numSamplesPerSlice;
-	UInt32 numSamplesPerSliceSize = sizeof numSamplesPerSlice;
-
-	internal *soundStruct = (internal *)malloc(sizeof(internal));
-	memset(soundStruct->realtimeBuffer, 0,
-		sizeof soundStruct->realtimeBuffer);
 
 	desc.componentType = kAudioUnitType_Output;
 	desc.componentSubType = kAudioUnitSubType_HALOutput;
@@ -75,105 +58,87 @@ bool CoreAudioSound::CoreAudioInit()
 	desc.componentManufacturer = kAudioUnitManufacturer_Apple;
 
 	Component component = FindNextComponent(NULL, &desc);
-	if (component == NULL)
+	if (component == NULL) {
 		printf("error finding audio component\n");
+		return false;
+	}
 
-	err = OpenAComponent(component, &soundStruct->audioUnit);
+	err = OpenAComponent(component, &audioUnit);
-	if (err)
+	if (err != noErr) {
 		printf("error opening audio component\n");
+		return false;
+	}
 
-	//enable output device
 	enableIO = 1;
-	AudioUnitSetProperty(soundStruct->audioUnit,
+	AudioUnitSetProperty(audioUnit,
 				kAudioOutputUnitProperty_EnableIO,
 				kAudioUnitScope_Output, 0, &enableIO,
 				sizeof enableIO);
 
-	//set audio format
 	FillOutASBDForLPCM(format, m_mixer->GetSampleRate(),
 				2, 16, 16, false, false, false);
-	err = AudioUnitSetProperty(soundStruct->audioUnit,
+	err = AudioUnitSetProperty(audioUnit,
 				kAudioUnitProperty_StreamFormat,
 				kAudioUnitScope_Input, 0, &format,
 				sizeof(AudioStreamBasicDescription));
-	if (err)
+	if (err != noErr) {
 		printf("error setting audio format\n");
+		return false;
+	}
 
 	callback_struct.inputProc = callback;
-	callback_struct.inputProcRefCon = soundStruct;
+	callback_struct.inputProcRefCon = this;
-	err = AudioUnitSetProperty(soundStruct->audioUnit,
+	err = AudioUnitSetProperty(audioUnit,
 				kAudioUnitProperty_SetRenderCallback,
 				kAudioUnitScope_Input, 0, &callback_struct,
 				sizeof callback_struct);
-	if (err)
+	if (err != noErr) {
 		printf("error setting audio callback\n");
+		return false;
+	}
 
-	err = AudioUnitGetProperty(soundStruct->audioUnit,
+	err = AudioUnitInitialize(audioUnit);
-				kAudioUnitProperty_MaximumFramesPerSlice,
+	if (err != noErr) {
-				kAudioUnitScope_Global, 0,
-				&numSamplesPerSlice, &numSamplesPerSliceSize);
-	if (err)
-		printf("error getting audio buffer size\n");
-
-	numBytesToRender = numSamplesPerSlice * 4;
-
-	err = AudioUnitInitialize(soundStruct->audioUnit);
-	if (err)
 		printf("error initializing audiounit\n");
+		return false;
+	}
 
-	err = AudioOutputUnitStart(soundStruct->audioUnit);
+	err = AudioOutputUnitStart(audioUnit);
-	if (err)
+	if (err != noErr) {
 		printf("error starting audiounit\n");
+		return false;
+	}
 
-	do
-	{
-		soundCriticalSection.Enter();
-		m_mixer->Mix(soundStruct->realtimeBuffer, numBytesToRender);
-		soundCriticalSection.Leave();
-		soundSyncEvent.Wait();
-	} while(!threadData);
-
-	err = AudioOutputUnitStop(soundStruct->audioUnit);
-	if (err)
-		printf("error stopping audiounit\n");
-
-	err = AudioUnitUninitialize(soundStruct->audioUnit);
-	if (err)
-		printf("error uninitializing audiounit\n");
-
-	err = CloseComponent(soundStruct->audioUnit);
-	if (err)
-		printf("error while closing audio component\n");
-
-	free(soundStruct);
 	return true;
 }
 
-void *coreAudioThread(void *args)
+void CoreAudioSound::SoundLoop()
 {
-
-	((CoreAudioSound *)args)->SoundLoop();
-	return NULL;
-}
-
-bool CoreAudioSound::Start()
-{
-	soundSyncEvent.Init();
-	thread = new Common::Thread(coreAudioThread, (void *)this);
-	return true;
 }
 
 void CoreAudioSound::Stop()
 {
-	threadData = 1;
+	OSStatus err;
-	soundSyncEvent.Set();
-	delete thread;
-	thread = NULL;
 
+	err = AudioOutputUnitStop(audioUnit);
+	if (err != noErr) {
+		printf("error stopping audiounit\n");
 		return;
 	}
 
+	err = AudioUnitUninitialize(audioUnit);
+	if (err != noErr) {
+		printf("error uninitializing audiounit\n");
+		return;
+	}
+
+	err = CloseComponent(audioUnit);
+	if (err != noErr) {
+		printf("error while closing audio component\n");
+		return;
+	}
+}
+
 void CoreAudioSound::Update()
 {
-	soundSyncEvent.Set();
 }

Source/Core/AudioCommon/Src/CoreAudioSoundStream.h

@@ -31,10 +31,12 @@
 class CoreAudioSound : public SoundStream
 {
 #if defined(__APPLE__)
-
 	Common::Thread *thread;
-        Common::CriticalSection soundCriticalSection;
 	Common::Event soundSyncEvent;
+	Common::CriticalSection soundCriticalSection;
+
+        ComponentDescription desc;
+        AudioUnit audioUnit;
 
 public:
 	CoreAudioSound(CMixer *mixer);
@@ -53,8 +55,7 @@ public:
 	
 	virtual void Update();
 
-private:
+	void RenderSamples(void *target, UInt32 size);
-	bool CoreAudioInit();
 #else
 public:
 	CoreAudioSound(CMixer *mixer) : SoundStream(mixer) {}
@@ -62,4 +63,3 @@ public:
 };
 
 #endif
-