cocoa_s.cpp

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00001 /* $Id: cocoa_s.cpp 13552 2008-06-17 19:38:00Z smatz $ */
00002 
00005 /*****************************************************************************
00006  *                             Cocoa sound driver                            *
00007  * Known things left to do:                                                  *
00008  * - Might need to do endian checking for it to work on both ppc and x86     *
00009  *****************************************************************************/
00010 
00011 #ifdef WITH_COCOA
00012 
00013 #define MAC_OS_X_VERSION_MIN_REQUIRED    MAC_OS_X_VERSION_10_3
00014 #include <AvailabilityMacros.h>
00015 
00016 #include <AudioUnit/AudioUnit.h>
00017 
00018 /* Name conflict */
00019 #define Rect        OTTDRect
00020 #define Point       OTTDPoint
00021 #define WindowClass OTTDWindowClass
00022 
00023 #include "../stdafx.h"
00024 #include "../debug.h"
00025 #include "../driver.h"
00026 #include "../mixer.h"
00027 #include "../core/endian_type.hpp"
00028 
00029 #include "cocoa_s.h"
00030 
00031 #undef WindowClass
00032 #undef Point
00033 #undef Rect
00034 
00035 static FSoundDriver_Cocoa iFSoundDriver_Cocoa;
00036 
00037 static AudioUnit _outputAudioUnit;
00038 
00039 /* The CoreAudio callback */
00040 static OSStatus audioCallback(void *inRefCon, AudioUnitRenderActionFlags *inActionFlags, const AudioTimeStamp *inTimeStamp, UInt32 inBusNumber, UInt32 inNumberFrames, AudioBufferList * ioData)
00041 {
00042   MxMixSamples(ioData->mBuffers[0].mData, ioData->mBuffers[0].mDataByteSize / 4);
00043 
00044   return noErr;
00045 }
00046 
00047 
00048 const char *SoundDriver_Cocoa::Start(const char * const *parm)
00049 {
00050   Component comp;
00051   ComponentDescription desc;
00052   struct AURenderCallbackStruct callback;
00053   AudioStreamBasicDescription requestedDesc;
00054 
00055   /* Setup a AudioStreamBasicDescription with the requested format */
00056   requestedDesc.mFormatID = kAudioFormatLinearPCM;
00057   requestedDesc.mFormatFlags = kLinearPCMFormatFlagIsPacked;
00058   requestedDesc.mChannelsPerFrame = 2;
00059   requestedDesc.mSampleRate = GetDriverParamInt(parm, "hz", 11025);
00060 
00061   requestedDesc.mBitsPerChannel = 16;
00062   requestedDesc.mFormatFlags |= kLinearPCMFormatFlagIsSignedInteger;
00063 
00064 #if TTD_ENDIAN == TTD_BIG_ENDIAN
00065   requestedDesc.mFormatFlags |= kLinearPCMFormatFlagIsBigEndian;
00066 #endif /* TTD_ENDIAN == TTD_BIG_ENDIAN */
00067 
00068   requestedDesc.mFramesPerPacket = 1;
00069   requestedDesc.mBytesPerFrame = requestedDesc.mBitsPerChannel * requestedDesc.mChannelsPerFrame / 8;
00070   requestedDesc.mBytesPerPacket = requestedDesc.mBytesPerFrame * requestedDesc.mFramesPerPacket;
00071 
00072 
00073   /* Locate the default output audio unit */
00074   desc.componentType = kAudioUnitType_Output;
00075   desc.componentSubType = kAudioUnitSubType_HALOutput;
00076   desc.componentManufacturer = kAudioUnitManufacturer_Apple;
00077   desc.componentFlags = 0;
00078   desc.componentFlagsMask = 0;
00079 
00080   comp = FindNextComponent (NULL, &desc);
00081   if (comp == NULL) {
00082     return "cocoa_s: Failed to start CoreAudio: FindNextComponent returned NULL";
00083   }
00084 
00085   /* Open & initialize the default output audio unit */
00086   if (OpenAComponent(comp, &_outputAudioUnit) != noErr) {
00087     return "cocoa_s: Failed to start CoreAudio: OpenAComponent";
00088   }
00089 
00090   if (AudioUnitInitialize(_outputAudioUnit) != noErr) {
00091     return "cocoa_s: Failed to start CoreAudio: AudioUnitInitialize";
00092   }
00093 
00094   /* Set the input format of the audio unit. */
00095   if (AudioUnitSetProperty(_outputAudioUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, 0, &requestedDesc, sizeof(requestedDesc)) != noErr) {
00096     return "cocoa_s: Failed to start CoreAudio: AudioUnitSetProperty (kAudioUnitProperty_StreamFormat)";
00097   }
00098 
00099   /* Set the audio callback */
00100   callback.inputProc = audioCallback;
00101   callback.inputProcRefCon = NULL;
00102   if (AudioUnitSetProperty(_outputAudioUnit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Input, 0, &callback, sizeof(callback)) != noErr) {
00103     return "cocoa_s: Failed to start CoreAudio: AudioUnitSetProperty (kAudioUnitProperty_SetRenderCallback)";
00104   }
00105 
00106   /* Finally, start processing of the audio unit */
00107   if (AudioOutputUnitStart(_outputAudioUnit) != noErr) {
00108     return "cocoa_s: Failed to start CoreAudio: AudioOutputUnitStart";
00109   }
00110 
00111   /* We're running! */
00112   return NULL;
00113 }
00114 
00115 
00116 void SoundDriver_Cocoa::Stop()
00117 {
00118   struct AURenderCallbackStruct callback;
00119 
00120   /* stop processing the audio unit */
00121   if (AudioOutputUnitStop(_outputAudioUnit) != noErr) {
00122     DEBUG(driver, 0, "cocoa_s: Core_CloseAudio: AudioOutputUnitStop failed");
00123     return;
00124   }
00125 
00126   /* Remove the input callback */
00127   callback.inputProc = 0;
00128   callback.inputProcRefCon = 0;
00129   if (AudioUnitSetProperty(_outputAudioUnit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Input, 0, &callback, sizeof(callback)) != noErr) {
00130     DEBUG(driver, 0, "cocoa_s: Core_CloseAudio: AudioUnitSetProperty (kAudioUnitProperty_SetRenderCallback) failed");
00131     return;
00132   }
00133 
00134   if (CloseComponent(_outputAudioUnit) != noErr) {
00135     DEBUG(driver, 0, "cocoa_s: Core_CloseAudio: CloseComponent failed");
00136     return;
00137   }
00138 }
00139 
00140 #endif /* WITH_COCOA */

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