medfall

commit 8ddb8f37ce2c412212502031a87497ad9dd306d4
parent 03796536a0751c52d8b14305f64671891b44aeb1
Author: Michael Savage <mikejsavage@gmail.com>
Date:   Mon Oct 24 23:11:48 +0300

Totally untested (not even compiled) OSX audio output code

Diffstat:
darwin_audio_output.cc
 | 
66
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
darwin_audio_output.h
 | 
12
++++++++++++
2 files changed, 78 insertions(+), 0 deletions(-)
diff --git a/darwin_audio_output.cc b/darwin_audio_output.cc
@@ -0,0 +1,66 @@
+#include <AudioToolbox/AudioToolbox.h>
+
+#include "intrinsics.h"
+#include "platform_audio_output.h"
+
+void audio_output_init() { }
+void audio_output_term() { }
+
+static OSStatus audio_output_callback(
+	void * data,
+	AudioUnitRenderActionFlags * ioActionFlags,
+	const AudioTimeStamp * inTimeStamp,
+	u32 inBusNumber, u32 num_samples,
+	AudioBufferList * buffers
+) {
+        AudioOutputDevice * device = ( AudioOutputDevice * ) data;
+
+        s16 * samples = ( s16 * ) buffers->mBuffers[ 0 ].mData;
+	device->callback( samples, checked_cast< s32 >( num_samples ) );
+
+        return 0;
+}
+
+void audio_output_open( AudioOutputDevice * device, AudioOutputCallback callback ) {
+	AudioComponentDescription desc = { };
+	desc.componentType = kAudioUnitType_Output;
+	desc.componentSubType = kAudioUnitSubType_RemoteIO;
+	desc.componentManufacturer = kAudioUnitManufacturer_Apple;
+
+	device->component = AudioComponentFindNext( NULL, &desc );
+	if( device->component == NULL ) {
+		FATAL( "AudioComponentFindNext" );
+	}
+
+	if( AudioComponentInstanceNew( component, &unit ) ) {
+		FATAL( "AudioComponentInstanceNew" );
+	}
+
+	AudioUnitInitialize( unit );
+
+	const int rate = 44100;
+	const int channels = 1;
+	AudioStreamBasicDescription stream_format = { };
+	stream_format.mSampleRate = rate;
+	stream_format.mFormatID = kAudioFormatLinearPCM;
+	stream_format.mFormatFlags = kAudioFormatFlagIsSignedInteger;
+	stream_format.mFramesPerPacket = 1;
+	stream_format.mChannelsPerFrame = channels;
+	stream_format.mBitsPerChannel = 16;
+	stream_format.mBytesPerPacket = channels * 2;
+	stream_format.mBytesPerFrame = channels * 2;
+
+	AudioUnitSetProperty( unit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, 0, &stream_format, sizeof( stream_format ) );
+
+	AURenderCallbackStruct cb = { };
+	cb.inputProc = audio_output_callback;
+	cb.inputProcRefCon = device;
+
+	AudioUnitSetProperty( unit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Global, 0, &cb, sizeof( AURenderCallbackStruct ) );
+
+	AudioOutputUnitStart( unit );
+}
+
+void audio_output_close( AudioOutputDevice * device ) {
+	FATAL( "need to implement audio_output_close" );
+}
diff --git a/darwin_audio_output.h b/darwin_audio_output.h
@@ -0,0 +1,12 @@
+#ifndef _DARWIN_AUDIO_OUTPUT_H_
+#define _DARWIN_AUDIO_OUTPUT_H_
+
+#include <AudioToolbox/AudioToolbox.h>
+
+struct AudioOutputDevice {
+	AudioComponent component;
+	AudioUnit unit;
+	AudioOutputCallback * callback;
+};
+
+#endif // _DARWIN_AUDIO_OUTPUT_H_