AGOS: implement Accolade AdLib + MT32 music drivers

- both known variants are supported (INSTR.DAT + MUSIC.DRV)
- INSTR.DAT/MUSIC.DRV holds channel mapping, instrument mapping, etc.
- fixed bug inside S1D MidiParser, that ruined some instrument changes
0xFC header was seen as 2 byte header, but it's 4 bytes in Elvira 2
and 5 bytes in Waxworks / Simon 1 demo
- dynamic channel allocation for the MUSIC.DRV adlib driver is not
implemented atm, simply because at least the demos of Waxworks and
Simon 1 do not use this feature
- sound effects of Waxworks are not implemented atm
- note: the game "Altered Destiny" uses Accolade INSTR.DAT variant too

1 files changed, 267 insertions, 0 deletions

diff --git a/engines/agos/drivers/accolade/mt32.cpp b/engines/agos/drivers/accolade/mt32.cpp
new file mode 100644
index 0000000000..6567d1d9ef
--- /dev/null
+++ b/engines/agos/drivers/accolade/mt32.cpp
@@ -0,0 +1,267 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "agos/agos.h"
+#include "agos/drivers/accolade/mididriver.h"
+
+#include "common/config-manager.h"
+#include "common/file.h"
+#include "common/mutex.h"
+#include "common/system.h"
+#include "common/textconsole.h"
+
+namespace AGOS {
+
+class MidiDriver_Accolade_MT32 : public MidiDriver {
+public:
+	MidiDriver_Accolade_MT32();
+	virtual ~MidiDriver_Accolade_MT32();
+
+	// MidiDriver
+	int open();
+	void close();
+	bool isOpen() const { return _isOpen; }
+
+	void send(uint32 b);
+
+	MidiChannel *allocateChannel() {
+		if (_driver)
+			return _driver->allocateChannel();
+		return NULL;
+	}
+	MidiChannel *getPercussionChannel() {
+		if (_driver)
+			return _driver->getPercussionChannel();
+		return NULL;
+	}
+
+	void setTimerCallback(void *timer_param, Common::TimerManager::TimerProc timer_proc) {
+		if (_driver)
+			_driver->setTimerCallback(timer_param, timer_proc);
+	}
+
+	uint32 getBaseTempo() {
+		if (_driver) {
+			return _driver->getBaseTempo();
+		}
+		return 1000000 / _baseFreq;
+	}
+
+protected:
+	Common::Mutex _mutex;
+	MidiDriver *_driver;
+	bool _MT32;
+	bool _nativeMT32;
+
+	bool _isOpen;
+	int _baseFreq;
+
+private:
+	// simple mapping between MIDI channel and MT32 channel
+	byte _MIDIchannelMapping[AGOS_MIDI_CHANNEL_COUNT];
+	// simple mapping between MIDI instruments and MT32 instruments
+	byte _MIDIinstrumentMapping[AGOS_MIDI_INSTRUMENT_COUNT];
+
+public:
+	bool setupInstruments(byte *instrumentData, uint16 instrumentDataSize, bool useMusicDrvFile);
+
+	void MT32SysEx(const byte *&dataPtr, int32 &bytesLeft);
+};
+
+MidiDriver_Accolade_MT32::MidiDriver_Accolade_MT32() {
+	_driver = NULL;
+	_isOpen = false;
+	_MT32 = false;
+	_nativeMT32 = false;
+	_baseFreq = 250;
+
+	memset(_MIDIchannelMapping, 0, sizeof(_MIDIchannelMapping));
+	memset(_MIDIinstrumentMapping, 0, sizeof(_MIDIinstrumentMapping));
+	//memset(_MIDIkeyNoteMapping, 0, sizeof(_MIDIkeyNoteMapping));
+}
+
+MidiDriver_Accolade_MT32::~MidiDriver_Accolade_MT32() {
+	Common::StackLock lock(_mutex);
+	if (_driver) {
+		_driver->setTimerCallback(0, 0);
+		_driver->close();
+		delete _driver;
+	}
+	_driver = NULL;
+}
+
+int MidiDriver_Accolade_MT32::open() {
+	assert(!_driver);
+
+//	debugC(kDebugLevelMT32Driver, "MT32: starting driver");
+
+	// Setup midi driver
+	MidiDriver::DeviceHandle dev = MidiDriver::detectDevice(MDT_MIDI | MDT_PREFER_MT32);
+	MusicType musicType = MidiDriver::getMusicType(dev);
+
+	switch (musicType) {
+	case MT_MT32:
+		_MT32       = true;
+		_nativeMT32 = false;
+		break;
+	case MT_GM:
+		if (ConfMan.getBool("native_mt32")) {
+			_MT32       = true;
+			_nativeMT32 = true;
+		}
+		break;
+	default:
+		break;
+	}
+
+	_driver = MidiDriver::createMidi(dev);
+	if (!_driver)
+		return 255;
+
+	if (_nativeMT32)
+		_driver->property(MidiDriver::PROP_CHANNEL_MASK, 0x03FE);
+
+	int ret = _driver->open();
+	if (ret)
+		return ret;
+
+	if (_MT32)
+		_driver->sendMT32Reset();
+	else
+		_driver->sendGMReset();
+
+	return 0;
+}
+
+void MidiDriver_Accolade_MT32::close() {
+	if (_driver) {
+		_driver->close();
+	}
+}
+
+// MIDI messages can be found at http://www.midi.org/techspecs/midimessages.php
+void MidiDriver_Accolade_MT32::send(uint32 b) {
+	byte command = b & 0xf0;
+	byte channel = b & 0xf;
+
+	if (command == 0xF0) {
+		if (_driver) {
+			_driver->send(b);
+		}
+		return;
+	}
+
+	byte mappedChannel = _MIDIchannelMapping[channel];
+
+	if (mappedChannel < AGOS_MIDI_CHANNEL_COUNT) {
+		// channel mapped to an actual MIDI channel, so use that one
+		b = (b & 0xFFFFFFF0) | mappedChannel;
+		if (command == 0xC0) {
+			// Program change
+			// Figure out the requested instrument
+			byte midiInstrument = (b >> 8) & 0xFF;
+			byte mappedInstrument = _MIDIinstrumentMapping[midiInstrument];
+			// And replace it
+			b = (b & 0xFFFF00FF) | (mappedInstrument << 8);
+		}
+
+		if (_driver) {
+			_driver->send(b);
+		}
+	}
+}
+
+// Called right at the start, we get an INSTR.DAT entry
+bool MidiDriver_Accolade_MT32::setupInstruments(byte *driverData, uint16 driverDataSize, bool useMusicDrvFile) {
+	uint16 channelMappingOffset = 0;
+	uint16 channelMappingSize = 0;
+	uint16 instrumentMappingOffset = 0;
+	uint16 instrumentMappingSize = 0;
+
+	if (!useMusicDrvFile) {
+		// INSTR.DAT: we expect at least 354 bytes
+		if (driverDataSize < 354)
+			return false;
+
+		// Data is like this:
+		// 128 bytes  instrument mapping
+		// 128 bytes  instrument volume adjust (signed!) (not used for MT32)
+		//  16 bytes  unknown
+		//  16 bytes  channel mapping
+		//  64 bytes  key note mapping (not really used for MT32)
+		//   1 byte   instrument count
+		//   1 byte   bytes per instrument
+		//   x bytes  no instruments used for MT32
+
+		channelMappingOffset    = 256 + 16;
+		channelMappingSize      = 16;
+		instrumentMappingOffset = 0;
+		instrumentMappingSize   = 128;
+
+	} else {
+		// MUSIC.DRV: we expect at least 468 bytes
+		if (driverDataSize < 468)
+			return false;
+
+		channelMappingOffset    = 396;
+		channelMappingSize      = 16;
+		instrumentMappingOffset = 140;
+		instrumentMappingSize   = 128;
+	}
+
+	// Channel mapping
+	if (channelMappingSize) {
+		// Get these 16 bytes for MIDI channel mapping
+		if (channelMappingSize != sizeof(_MIDIchannelMapping))
+			return false;
+
+		memcpy(_MIDIchannelMapping, driverData + channelMappingOffset, sizeof(_MIDIchannelMapping));
+	} else {
+		// Set up straight mapping
+		for (uint16 channelNr = 0; channelNr < sizeof(_MIDIchannelMapping); channelNr++) {
+			_MIDIchannelMapping[channelNr] = channelNr;
+		}
+	}
+
+	if (instrumentMappingSize) {
+		// And these for instrument mapping
+		if (instrumentMappingSize > sizeof(_MIDIinstrumentMapping))
+			return false;
+
+		memcpy(_MIDIinstrumentMapping, driverData + instrumentMappingOffset, instrumentMappingSize);
+	}
+	// Set up straight mapping for the remaining data
+	for (uint16 instrumentNr = instrumentMappingSize; instrumentNr < sizeof(_MIDIinstrumentMapping); instrumentNr++) {
+		_MIDIinstrumentMapping[instrumentNr] = instrumentNr;
+	}
+	return true;
+}
+
+MidiDriver *MidiDriver_Accolade_MT32_create() {
+	return new MidiDriver_Accolade_MT32();
+}
+
+bool MidiDriver_Accolade_MT32_setupInstruments(MidiDriver *driver, byte *instrumentData, uint16 instrumentDataSize, bool useMusicDrvFile) {
+	return static_cast<MidiDriver_Accolade_MT32 *>(driver)->setupInstruments(instrumentData, instrumentDataSize, useMusicDrvFile);
+}
+
+} // End of namespace AGOS