BACKENDS: Partial merge of gsoc2010-opengl: Audio CD changes only

This commit contains the AudioCDManager changes from the gsoc2010-opengl
branch. The other changes in that branch are restricted to the backends
directory only (plus configure).

The Nintendo DS and Dreamcast ports still need to be ported over to
the new Audio CD system, but that should be fairly easy to do.

svn-id: r54147

1 files changed, 157 insertions, 0 deletions

diff --git a/backends/audiocd/default/default-audiocd.cpp b/backends/audiocd/default/default-audiocd.cpp
new file mode 100644
index 0000000000..6d16b26652
--- /dev/null
+++ b/backends/audiocd/default/default-audiocd.cpp
@@ -0,0 +1,157 @@
+/* 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.
+ *
+ * $URL$
+ * $Id$
+ *
+ */
+
+#include "backends/audiocd/default/default-audiocd.h"
+#include "sound/audiostream.h"
+#include "common/system.h"
+
+DefaultAudioCDManager::DefaultAudioCDManager() {
+	_cd.playing = false;
+	_cd.track = 0;
+	_cd.start = 0;
+	_cd.duration = 0;
+	_cd.numLoops = 0;
+	_cd.volume = Audio::Mixer::kMaxChannelVolume;
+	_cd.balance = 0;
+	_mixer = g_system->getMixer();
+	_emulating = false;
+	assert(_mixer);
+}
+
+void DefaultAudioCDManager::play(int track, int numLoops, int startFrame, int duration, bool only_emulate) {
+	if (numLoops != 0 || startFrame != 0) {
+		_cd.track = track;
+		_cd.numLoops = numLoops;
+		_cd.start = startFrame;
+		_cd.duration = duration;
+
+		// Try to load the track from a compressed data file, and if found, use
+		// that. If not found, attempt to start regular Audio CD playback of
+		// the requested track.
+		char trackName[2][16];
+		sprintf(trackName[0], "track%d", track);
+		sprintf(trackName[1], "track%02d", track);
+		Audio::SeekableAudioStream *stream = 0;
+
+		for (int i = 0; !stream && i < 2; ++i)
+			stream = Audio::SeekableAudioStream::openStreamFile(trackName[i]);
+
+		// Stop any currently playing emulated track
+		_mixer->stopHandle(_handle);
+
+		if (stream != 0) {
+			Audio::Timestamp start = Audio::Timestamp(0, startFrame, 75);
+			Audio::Timestamp end = duration ? Audio::Timestamp(0, startFrame + duration, 75) : stream->getLength();
+
+			/*
+			FIXME: Seems numLoops == 0 and numLoops == 1 both indicate a single repetition,
+			while all other positive numbers indicate precisely the number of desired
+			repetitions. Finally, -1 means infinitely many
+			*/
+			_emulating = true;
+			_mixer->playStream(Audio::Mixer::kMusicSoundType, &_handle,
+			                        Audio::makeLoopingAudioStream(stream, start, end, (numLoops < 1) ? numLoops + 1 : numLoops), -1, _cd.volume, _cd.balance);
+		} else {
+			_emulating = false;
+			if (!only_emulate)
+				playCD(track, numLoops, startFrame, duration);
+		}
+	}
+}
+
+void DefaultAudioCDManager::stop() {
+	if (_emulating) {
+		// Audio CD emulation
+		_mixer->stopHandle(_handle);
+		_emulating = false;
+	} else {
+		// Real Audio CD
+		stopCD();
+	}
+}
+
+bool DefaultAudioCDManager::isPlaying() const {
+	if (_emulating) {
+		// Audio CD emulation
+		return _mixer->isSoundHandleActive(_handle);
+	} else {
+		// Real Audio CD
+		return pollCD();
+	}
+}
+
+void DefaultAudioCDManager::setVolume(byte volume) {
+	_cd.volume = volume;
+	if (_emulating) {
+		// Audio CD emulation
+		if (_mixer->isSoundHandleActive(_handle))
+			_mixer->setChannelVolume(_handle, _cd.volume);
+	} else {
+		// Real Audio CD
+
+		// Unfortunately I can't implement this atm
+		// since SDL doesn't seem to offer an interface method for this.
+
+		// g_system->setVolumeCD(_cd.volume);
+	}
+}
+
+void DefaultAudioCDManager::setBalance(int8 balance) {
+	_cd.balance = balance;
+	if (_emulating) {
+		// Audio CD emulation
+		if (isPlaying())
+			_mixer->setChannelBalance(_handle, _cd.balance);
+	} else {
+		// Real Audio CD
+
+		// Unfortunately I can't implement this atm
+		// since SDL doesn't seem to offer an interface method for this.
+
+		// g_system->setBalanceCD(_cd.balance);
+	}
+}
+
+void DefaultAudioCDManager::update() {
+	if (_emulating) {
+		// Check whether the audio track stopped playback
+		if (!_mixer->isSoundHandleActive(_handle)) {
+			// FIXME: We do not update the numLoops parameter here (and in fact,
+			// currently can't do that). Luckily, only one engine ever checks
+			// this part of the AudioCD status, namely the SCUMM engine; and it
+			// only checks whether the track is currently set to infinite looping
+			// or not.
+			_emulating = false;
+		}
+	} else {
+		updateCD();
+	}
+}
+
+DefaultAudioCDManager::Status DefaultAudioCDManager::getStatus() const {
+	Status info = _cd;
+	info.playing = isPlaying();
+	return info;
+}