scummvm/kyra/sound.cpp

/* ScummVM - Scumm Interpreter
 * Copyright (C) 2004-2005 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.
 *
 * $Header$
 *
 */

#include "kyra/sound.h"
#include "kyra/resource.h"

namespace Kyra {
	MusicPlayer::MusicPlayer(MidiDriver* driver, KyraEngine* engine) {
		_engine = engine;
		_driver = driver;
		_passThrough = false;
		_isPlaying = _nativeMT32 = false;

		memset(_channel, 0, sizeof(MidiChannel*) * 16);
		memset(_channelVolume, 255, sizeof(uint8) * 16);
		_volume = 0;

		int ret = open();
		if (ret != MERR_ALREADY_OPEN && ret != 0) {
			error("couldn't open midi driver");
		}
	}

	MusicPlayer::~MusicPlayer() {
		_driver->setTimerCallback(NULL, NULL);
		close();
	}

	void MusicPlayer::setVolume(int volume) {
		if (volume < 0)
			volume = 0;
		else if (volume > 255)
			volume = 255;

		if (_volume == volume)
			return;

		_volume = volume;

		for (int i = 0; i < 16; ++i) {
			if (_channel[i]) {
				_channel[i]->volume(_channelVolume[i] * _volume / 255);
			}
		}
	}

	int MusicPlayer::open() {
		// Don't ever call open without first setting the output driver!
		if (!_driver)
			return 255;

		int ret = _driver->open();
		if (ret)
			return ret;

		_driver->setTimerCallback(this, &onTimer);
		return 0;
	}

	void MusicPlayer::close() {
		if (_driver)
			_driver->close();
		_driver = 0;
	}

	void MusicPlayer::send(uint32 b) {
		if (_passThrough) {
			_driver->send(b);
			return;
		}

		uint8 channel = (byte)(b & 0x0F);
		if ((b & 0xFFF0) == 0x07B0) {
			// Adjust volume changes by master volume
			uint8 volume = (uint8)((b >> 16) & 0x7F);
			_channelVolume[channel] = volume;
			volume = volume * _volume / 255;
			b = (b & 0xFF00FFFF) | (volume << 16);
		} else if ((b & 0xF0) == 0xC0 && !_nativeMT32) {
			b = (b & 0xFFFF00FF) | MidiDriver::_mt32ToGm[(b >> 8) & 0xFF] << 8;
		} else if ((b & 0xFFF0) == 0x007BB0) {
			//Only respond to All Notes Off if this channel
			//has currently been allocated
			if (!_channel[channel])
				return;
		}

		if (!_channel[channel])
			_channel[channel] = (channel == 9) ? _driver->getPercussionChannel() : _driver->allocateChannel();

		if (_channel[channel])
			_channel[channel]->send(b);
	}

	void MusicPlayer::metaEvent(byte type, byte *data, uint16 length) {
		switch (type) {
			case 0x2F:	// End of Track
				_parser->jumpToTick(0);
			break;
			default:
				warning("Unhandled meta event: 0x%02x", type);
			break;
		}
	}

	void MusicPlayer::playMusic(const char* file) {
		uint32 size;
		uint8* data = 0;

		data = (_engine->resManager())->fileData(file, &size);

		if (!data) {
			warning("couldn't load '%s'", file);
			return;
		}

		playMusic(data, size);
	}

	void MusicPlayer::playMusic(uint8* data, uint32 size) {
		if (_isPlaying)
			stopMusic();

		_parser = MidiParser::createParser_XMIDI();
		assert(_parser);

		if (!_parser->loadMusic(data, size)) {
			warning("Error reading track!");
			delete _parser;
			_parser = 0;
			return;
		}

		_parser->setTrack(0);
		_parser->setMidiDriver(this);
		_parser->setTimerRate(getBaseTempo());

		_isPlaying = true;
	}

	void MusicPlayer::stopMusic() {
		_isPlaying = false;
		if (_parser) {
			_parser->unloadMusic();
			delete _parser;
			_parser = NULL;
		}
	}

	void MusicPlayer::onTimer(void *refCon) {
		MusicPlayer *music = (MusicPlayer *)refCon;
		if (music->_isPlaying)
			music->_parser->onTimer();
	}

	void MusicPlayer::playTrack(uint8 track) {
		if (_parser) {
			_isPlaying = true;
			_parser->setTrack(track);
			_parser->jumpToTick(0);
		}
	}
} // end of namespace Kyra