cocoa_s.cpp

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00001 /* $Id: cocoa_s.cpp 16804 2009-07-13 10:16:50Z rubidium $ */
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   MxInitialize(requestedDesc.mSampleRate);
00073 
00074   /* Locate the default output audio unit */
00075   desc.componentType = kAudioUnitType_Output;
00076   desc.componentSubType = kAudioUnitSubType_HALOutput;
00077   desc.componentManufacturer = kAudioUnitManufacturer_Apple;
00078   desc.componentFlags = 0;
00079   desc.componentFlagsMask = 0;
00080 
00081   comp = FindNextComponent (NULL, &desc);
00082   if (comp == NULL) {
00083     return "cocoa_s: Failed to start CoreAudio: FindNextComponent returned NULL";
00084   }
00085 
00086   /* Open & initialize the default output audio unit */
00087   if (OpenAComponent(comp, &_outputAudioUnit) != noErr) {
00088     return "cocoa_s: Failed to start CoreAudio: OpenAComponent";
00089   }
00090 
00091   if (AudioUnitInitialize(_outputAudioUnit) != noErr) {
00092     return "cocoa_s: Failed to start CoreAudio: AudioUnitInitialize";
00093   }
00094 
00095   /* Set the input format of the audio unit. */
00096   if (AudioUnitSetProperty(_outputAudioUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, 0, &requestedDesc, sizeof(requestedDesc)) != noErr) {
00097     return "cocoa_s: Failed to start CoreAudio: AudioUnitSetProperty (kAudioUnitProperty_StreamFormat)";
00098   }
00099 
00100   /* Set the audio callback */
00101   callback.inputProc = audioCallback;
00102   callback.inputProcRefCon = NULL;
00103   if (AudioUnitSetProperty(_outputAudioUnit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Input, 0, &callback, sizeof(callback)) != noErr) {
00104     return "cocoa_s: Failed to start CoreAudio: AudioUnitSetProperty (kAudioUnitProperty_SetRenderCallback)";
00105   }
00106 
00107   /* Finally, start processing of the audio unit */
00108   if (AudioOutputUnitStart(_outputAudioUnit) != noErr) {
00109     return "cocoa_s: Failed to start CoreAudio: AudioOutputUnitStart";
00110   }
00111 
00112   /* We're running! */
00113   return NULL;
00114 }
00115 
00116 
00117 void SoundDriver_Cocoa::Stop()
00118 {
00119   struct AURenderCallbackStruct callback;
00120 
00121   /* stop processing the audio unit */
00122   if (AudioOutputUnitStop(_outputAudioUnit) != noErr) {
00123     DEBUG(driver, 0, "cocoa_s: Core_CloseAudio: AudioOutputUnitStop failed");
00124     return;
00125   }
00126 
00127   /* Remove the input callback */
00128   callback.inputProc = 0;
00129   callback.inputProcRefCon = 0;
00130   if (AudioUnitSetProperty(_outputAudioUnit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Input, 0, &callback, sizeof(callback)) != noErr) {
00131     DEBUG(driver, 0, "cocoa_s: Core_CloseAudio: AudioUnitSetProperty (kAudioUnitProperty_SetRenderCallback) failed");
00132     return;
00133   }
00134 
00135   if (CloseComponent(_outputAudioUnit) != noErr) {
00136     DEBUG(driver, 0, "cocoa_s: Core_CloseAudio: CloseComponent failed");
00137     return;
00138   }
00139 }
00140 
00141 #endif /* WITH_COCOA */

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