1 files changed, 133 insertions, 0 deletions
diff --git a/backends/midi/coreaudio.cpp b/backends/midi/coreaudio.cpp
new file mode 100644
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+++ b/backends/midi/coreaudio.cpp
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+/* ScummVM - Scumm Interpreter
+ * Copyright (C) 2001/2002 The ScummVM 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; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * $Header$
+ */
+
+#ifdef MACOSX
+
+#include "sound/mpu401.h"
+
+#include <AudioUnit/AudioUnit.h>
+
+
+// FIXME - the following disables reverb support in the QuickTime / CoreAudio
+// midi backends. For some reasons, reverb will suck away a *lot* of CPU time.
+// Until we know for sure what is causing this and if there is a better way to
+// fix the problem, we just disable all reverb for these backends.
+#define COREAUDIO_REVERB_HACK
+
+
+/* CoreAudio MIDI driver
+ * Based on code by Benjamin W. Zale
+ * Extended by Max Horn
+ */
+class MidiDriver_CORE : public MidiDriver_MPU401 {
+public:
+	MidiDriver_CORE() : au_MusicDevice(0), au_output(0) { }
+	int open(int mode);
+	void close();
+	void send(uint32 b);
+	void pause(bool p) { }
+	void set_stream_callback(void *param, StreamCallback *sc) { }
+
+private:
+	AudioUnit au_MusicDevice;
+	AudioUnit au_output;
+
+	int _mode;
+};
+
+
+int MidiDriver_CORE::open(int mode)
+{
+	if (au_output != NULL)
+		return MERR_ALREADY_OPEN;
+
+	if (mode == MO_STREAMING)
+		return MERR_STREAMING_NOT_AVAILABLE;
+
+	_mode = mode;
+
+	int err;
+	AudioUnitConnection auconnect;
+	ComponentDescription compdesc;
+	Component compid;
+
+	// Open the Music Device
+	compdesc.componentType = kAudioUnitComponentType;
+	compdesc.componentSubType = kAudioUnitSubType_MusicDevice;
+	compdesc.componentManufacturer = kAudioUnitID_DLSSynth;
+	compdesc.componentFlags = 0;
+	compdesc.componentFlagsMask = 0;
+	compid = FindNextComponent(NULL, &compdesc);
+	au_MusicDevice = (AudioUnit) OpenComponent(compid);
+
+	// open the output unit
+	au_output = (AudioUnit) OpenDefaultComponent(kAudioUnitComponentType, kAudioUnitSubType_Output);
+
+	// connect the units
+	auconnect.sourceAudioUnit = au_MusicDevice;
+	auconnect.sourceOutputNumber = 0;
+	auconnect.destInputNumber = 0;
+	err =
+		AudioUnitSetProperty(au_output, kAudioUnitProperty_MakeConnection, kAudioUnitScope_Input, 0,
+												 (void *)&auconnect, sizeof(AudioUnitConnection));
+
+	// initialize the units
+	AudioUnitInitialize(au_MusicDevice);
+	AudioUnitInitialize(au_output);
+
+	// start the output
+	AudioOutputUnitStart(au_output);
+
+	return 0;
+}
+
+void MidiDriver_CORE::close()
+{
+	// Stop the output
+	AudioOutputUnitStop(au_output);
+
+	// Cleanup
+	CloseComponent(au_output);
+	CloseComponent(au_MusicDevice);
+
+	_mode = 0;
+}
+
+void MidiDriver_CORE::send(uint32 b)
+{
+	unsigned char first_byte, seccond_byte, status_byte;
+	status_byte = (b & 0x000000FF);
+	first_byte = (b & 0x0000FF00) >> 8;
+	seccond_byte = (b & 0x00FF0000) >> 16;
+
+#ifdef COREAUDIO_REVERB_HACK
+	if ((status_byte&0xF0) == 0xB0 && first_byte == 0x5b)
+		return;
+#endif
+
+	MusicDeviceMIDIEvent(au_MusicDevice, status_byte, first_byte, seccond_byte, 0);
+}
+
+MidiDriver *MidiDriver_CORE_create()
+{
+	return new MidiDriver_CORE();
+}
+
+#endif // MACOSX