MOHAWK: Separate background sound handling from other sounds for Myst. Allow the scripts to change the background sound volume.

svn-id: r54953

8 files changed, 116 insertions, 56 deletions

diff --git a/engines/mohawk/console.cpp b/engines/mohawk/console.cpp
index d406d7575c..bf1d9b02ce 100644
--- a/engines/mohawk/console.cpp
+++ b/engines/mohawk/console.cpp
@@ -215,8 +215,7 @@ bool MystConsole::Cmd_PlaySound(int argc, const char **argv) {
 		return true;
 	}
 
-	_vm->_sound->stopSound();
-	_vm->_sound->playSound((uint16)atoi(argv[1]));
+	_vm->_sound->replaceSound((uint16)atoi(argv[1]));
 
 	return false;
 }
diff --git a/engines/mohawk/myst.cpp b/engines/mohawk/myst.cpp
index 15232966dd..be3a776b60 100644
--- a/engines/mohawk/myst.cpp
+++ b/engines/mohawk/myst.cpp
@@ -453,6 +453,7 @@ void MohawkEngine_Myst::changeToStack(uint16 stack) {
 	// Clear the resource cache and the image cache
 	_cache.clear();
 	_gfx->clearCache();
+	_sound->stopBackground();
 }
 
 uint16 MohawkEngine_Myst::getCardBackgroundId() {
@@ -521,27 +522,17 @@ void MohawkEngine_Myst::changeToCard(uint16 card, bool updateScreen) {
 		soundActionVolume = _view.soundVolume;
 	}
 
-	// NOTE: Mixer only has 8-bit channel volume granularity,
-	// Myst uses 16-bit? Or is part of this balance?
-	soundActionVolume = (byte)(soundActionVolume / 255);
-
 	if (soundAction == kMystSoundActionContinue)
 		debug(2, "Continuing with current sound");
 	else if (soundAction == kMystSoundActionChangeVolume) {
 		debug(2, "Continuing with current sound, changing volume");
-		// TODO: Implement Volume Control..
+		_sound->changeBackgroundVolume(soundActionVolume);
 	} else if (soundAction == kMystSoundActionStop) {
 		debug(2, "Stopping sound");
-		_sound->stopSound();
+		_sound->stopBackground();
 	} else if (soundAction > 0) {
 		debug(2, "Playing new sound %d", soundAction);
-		_sound->stopSound();
-		// TODO: Need to keep sound handle and add function to change volume of
-		// looped running sound for kMystSoundActionChangeVolume type
-
-		// NOTE: All sounds are looped when played via the sound section of the
-		// VIEW resources.
-		_sound->playSound(soundAction, soundActionVolume, true);
+		_sound->replaceBackground(soundAction, soundActionVolume);
 	} else {
 		error("Unknown sound action %d", soundAction);
 	}
diff --git a/engines/mohawk/myst_areas.cpp b/engines/mohawk/myst_areas.cpp
index 5b27a69ab9..6377f3255c 100644
--- a/engines/mohawk/myst_areas.cpp
+++ b/engines/mohawk/myst_areas.cpp
@@ -171,14 +171,20 @@ MystResourceType6::MystResourceType6(MohawkEngine_Myst *vm, Common::SeekableRead
 	_videoFile = convertMystVideoName(_videoFile);
 
 	// Position values require modulus 10000 to keep in sane range.
-	_left = rlstStream->readUint16LE() % 10000;
-	_top = rlstStream->readUint16LE() % 10000;
+	_left = rlstStream->readSint16LE() % 10000;
+	_top = rlstStream->readSint16LE() % 10000;
 	_playOnCardChange = rlstStream->readUint16LE();
 	_direction = rlstStream->readUint16LE();
 	_playBlocking = rlstStream->readUint16LE();
 	_loop = rlstStream->readUint16LE();
 	_u3 = rlstStream->readUint16LE();
 
+	// TODO: Out of bound values should clip the movie
+	if (_left < 0)
+		_left = 0;
+	if (_top < 0)
+		_top = 0;
+
 	if (_direction != 1)
 		warning("Type 6 _u0 != 1");
 	if (_u3 != 0)
@@ -648,7 +654,7 @@ void MystResourceType10::updatePosition(const Common::Point &mouse) {
 	}
 
 	if (positionChanged && _dragSound) {
-		_vm->_sound->playSound(_dragSound);
+		_vm->_sound->replaceSound(_dragSound);
 	}
 }
 
diff --git a/engines/mohawk/myst_areas.h b/engines/mohawk/myst_areas.h
index 0aa5f082f6..6e84747fe4 100644
--- a/engines/mohawk/myst_areas.h
+++ b/engines/mohawk/myst_areas.h
@@ -112,8 +112,8 @@ public:
 protected:
 	static Common::String convertMystVideoName(Common::String name);
 	Common::String _videoFile;
-	uint16 _left;
-	uint16 _top;
+	int16 _left;
+	int16 _top;
 	uint16 _loop;
 	uint16 _direction; // 1 => forward, -1 => backwards
 	uint16 _playBlocking;
diff --git a/engines/mohawk/myst_scripts.cpp b/engines/mohawk/myst_scripts.cpp
index 279de90226..bf1aadcea0 100644
--- a/engines/mohawk/myst_scripts.cpp
+++ b/engines/mohawk/myst_scripts.cpp
@@ -128,7 +128,7 @@ void MystScriptParser::setupCommonOpcodes() {
 	OPCODE(27, o_playSoundBlocking);
 	OPCODE(28, o_copyBackBufferToScreen);
 	OPCODE(29, o_copyImageToBackBuffer);
-	OPCODE(30, o_changeSound);
+	OPCODE(30, o_changeBackgroundSound);
 	OPCODE(31, o_soundPlaySwitch);
 	OPCODE(32, o_soundResumeBackground);
 	OPCODE(33, o_copyImageToScreen);
@@ -558,14 +558,14 @@ void MystScriptParser::o_playSound(uint16 op, uint16 var, uint16 argc, uint16 *a
 		debugC(kDebugScript, "Opcode %d: playSound", op);
 		debugC(kDebugScript, "\tsoundId: %d", soundId);
 
-		_vm->_sound->playSound(soundId);
+		_vm->_sound->replaceSound(soundId);
 	} else
 		unknown(op, var, argc, argv);
 }
 
 void MystScriptParser::o_stopSoundBackground(uint16 op, uint16 var, uint16 argc, uint16 *argv) {
 	debugC(kDebugScript, "Opcode %d: stopSoundBackground", op);
-	//_vm->_sound->stopBackground();
+	_vm->_sound->stopBackground();
 }
 
 void MystScriptParser::o_playSoundBlocking(uint16 op, uint16 var, uint16 argc, uint16 *argv) {
@@ -636,7 +636,7 @@ void MystScriptParser::o_copyImageToBackBuffer(uint16 op, uint16 var, uint16 arg
 //       Current behaviour here and with VIEW sound block is not right as demonstrated
 //       by Channelwood Card 3280 (Tank Valve) and water flow sound behaviour in pipe
 //       on cards leading from shed...
-void MystScriptParser::o_changeSound(uint16 op, uint16 var, uint16 argc, uint16 *argv) {
+void MystScriptParser::o_changeBackgroundSound(uint16 op, uint16 var, uint16 argc, uint16 *argv) {
 	varUnusedCheck(op, var);
 
 	int16 *soundList = NULL;
@@ -682,27 +682,20 @@ void MystScriptParser::o_changeSound(uint16 op, uint16 var, uint16 argc, uint16
 			}
 		}
 
-		// NOTE: Mixer only has 8-bit channel volume granularity,
-		// Myst uses 16-bit? Or is part of this balance?
-		soundVolume = (byte)(soundVolume / 255);
-
 		if (soundAction == kMystSoundActionContinue)
 			debugC(kDebugScript, "Continue current sound");
 		else if (soundAction == kMystSoundActionChangeVolume) {
 			debugC(kDebugScript, "Continue current sound, change volume");
 			debugC(kDebugScript, "\tVolume: %d", soundVolume);
-			// TODO: Implement Volume Control..
+			_vm->_sound->changeBackgroundVolume(soundVolume);
 		} else if (soundAction == kMystSoundActionStop) {
 			debugC(kDebugScript, "Stop sound");
-			_vm->_sound->stopSound();
+			_vm->_sound->stopBackground();
 		} else if (soundAction > 0) {
 			debugC(kDebugScript, "Play new Sound, change volume");
 			debugC(kDebugScript, "\tSound: %d", soundAction);
 			debugC(kDebugScript, "\tVolume: %d", soundVolume);
-			_vm->_sound->stopSound();
-			// TODO: Need to keep sound handle and add function to change volume of
-			// looped running sound for kMystSoundActionChangeVolume type
-			_vm->_sound->playSound(soundAction, soundVolume);
+			_vm->_sound->replaceBackground(soundAction, soundVolume);
 		} else {
 			debugC(kDebugScript, "Unknown");
 			warning("Unknown sound control value in opcode %d", op);
@@ -726,13 +719,13 @@ void MystScriptParser::o_soundPlaySwitch(uint16 op, uint16 var, uint16 argc, uin
 		debugC(kDebugScript, "\tsoundId: %d", soundId);
 
 		if (soundId)
-			_vm->_sound->playSound(soundId);
+			_vm->_sound->replaceSound(soundId);
 	}
 }
 
 void MystScriptParser::o_soundResumeBackground(uint16 op, uint16 var, uint16 argc, uint16 *argv) {
 	debugC(kDebugScript, "Opcode %d: soundResumeBackground", op);
-	//_vm->_sound->resumeBackground();
+	_vm->_sound->resumeBackground();
 }
 
 void MystScriptParser::o_copyImageToScreen(uint16 op, uint16 var, uint16 argc, uint16 *argv) {
@@ -857,7 +850,7 @@ void MystScriptParser::o_changeStack(uint16 op, uint16 var, uint16 argc, uint16
 			// wrong as you're not actually linking when using this opcode. The sounds are only
 			// played for the full game linking.
 			if (!_vm->_tweaksEnabled) {
-				handle= _vm->_sound->playSound(soundIdLinkSrc);
+				handle= _vm->_sound->replaceSound(soundIdLinkSrc);
 				while (_vm->_mixer->isSoundHandleActive(*handle))
 					_vm->_system->delayMillis(10);
 			}
@@ -872,12 +865,12 @@ void MystScriptParser::o_changeStack(uint16 op, uint16 var, uint16 argc, uint16
 			}
 
 			if (!_vm->_tweaksEnabled) {
-				handle = _vm->_sound->playSound(soundIdLinkDst);
+				handle = _vm->_sound->replaceSound(soundIdLinkDst);
 				while (_vm->_mixer->isSoundHandleActive(*handle))
 					_vm->_system->delayMillis(10);
 			}
 		} else {
-			handle = _vm->_sound->playSound(soundIdLinkSrc);
+			handle = _vm->_sound->replaceSound(soundIdLinkSrc);
 			while (_vm->_mixer->isSoundHandleActive(*handle))
 				_vm->_system->delayMillis(10);
 
@@ -886,7 +879,7 @@ void MystScriptParser::o_changeStack(uint16 op, uint16 var, uint16 argc, uint16
 			_vm->changeToStack(_stackMap[targetStack]);
 			_vm->changeToCard(_startCard[targetStack], true);
 
-			handle = _vm->_sound->playSound(soundIdLinkDst);
+			handle = _vm->_sound->replaceSound(soundIdLinkDst);
 			while (_vm->_mixer->isSoundHandleActive(*handle))
 				_vm->_system->delayMillis(10);
 		}
@@ -908,7 +901,7 @@ void MystScriptParser::o_changeCardPlaySoundDirectional(uint16 op, uint16 var, u
 	debugC(kDebugScript, "\tanimated update data size: %d", dataSize);
 
 	if (soundId)
-		_vm->_sound->playSound(soundId);
+		_vm->_sound->replaceSound(soundId);
 
 	_vm->changeToCard(cardId, false);
 
@@ -927,7 +920,7 @@ void MystScriptParser::o_directionalUpdatePlaySound(uint16 op, uint16 var, uint1
 	debugC(kDebugScript, "\tanimated update data size: %d", dataSize);
 
 	if (soundId)
-		_vm->_sound->playSound(soundId);
+		_vm->_sound->replaceSound(soundId);
 
 	animatedUpdate(dataSize, &argv[3], delayBetweenSteps);
 }
diff --git a/engines/mohawk/myst_scripts.h b/engines/mohawk/myst_scripts.h
index f455daf66d..f16c4fcbd9 100644
--- a/engines/mohawk/myst_scripts.h
+++ b/engines/mohawk/myst_scripts.h
@@ -103,7 +103,7 @@ public:
 	DECLARE_OPCODE(o_playSoundBlocking);
 	DECLARE_OPCODE(o_copyBackBufferToScreen);
 	DECLARE_OPCODE(o_copyImageToBackBuffer);
-	DECLARE_OPCODE(o_changeSound);
+	DECLARE_OPCODE(o_changeBackgroundSound);
 	DECLARE_OPCODE(o_soundPlaySwitch);
 	DECLARE_OPCODE(o_copyImageToScreen);
 	DECLARE_OPCODE(o_soundResumeBackground);
diff --git a/engines/mohawk/sound.cpp b/engines/mohawk/sound.cpp
index 29a097e591..aec01dcdd5 100644
--- a/engines/mohawk/sound.cpp
+++ b/engines/mohawk/sound.cpp
@@ -70,9 +70,7 @@ void Sound::initMidi() {
 	_midiParser->setTimerRate(_midiDriver->getBaseTempo());
 }
 
-Audio::SoundHandle *Sound::playSound(uint16 id, byte volume, bool loop) {
-	debug (0, "Playing sound %d", id);
-
+Audio::AudioStream *Sound::makeAudioStream(uint16 id) {
 	Audio::AudioStream *audStream = NULL;
 
 	switch (_vm->getGameType()) {
@@ -103,6 +101,14 @@ Audio::SoundHandle *Sound::playSound(uint16 id, byte volume, bool loop) {
 		audStream = makeMohawkWaveStream(_vm->getResource(ID_TWAV, id));
 	}
 
+	return audStream;
+}
+
+Audio::SoundHandle *Sound::playSound(uint16 id, byte volume, bool loop) {
+	debug (0, "Playing sound %d", id);
+
+	Audio::AudioStream *audStream = makeAudioStream(id);
+
 	if (audStream) {
 		SndHandle *handle = getHandle();
 		handle->type = kUsedHandle;
@@ -127,12 +133,11 @@ Audio::SoundHandle *Sound::replaceSound(uint16 id, byte volume, bool loop) {
 	Common::String name = _vm->getResourceName(ID_MSND, id);
 
 	// Check if sound is already playing
-	for (uint32 i = 0; i < _handles.size(); i++) {
-		if (_vm->_mixer->isSoundHandleActive(_handles[i].handle)
-				&& name.equals(_vm->getResourceName(ID_MSND, _handles[i].id))) {
+	for (uint32 i = 0; i < _handles.size(); i++)
+		if (_handles[i].type == kUsedHandle
+				&& _vm->_mixer->isSoundHandleActive(_handles[i].handle)
+				&& name.equals(_vm->getResourceName(ID_MSND, _handles[i].id)))
 			return &_handles[i].handle;
-		}
-	}
 
 	stopSound();
 	return playSound(id, volume, loop);
@@ -552,4 +557,66 @@ bool Sound::isPlaying(uint16 id) {
 	return false;
 }
 
+Audio::SoundHandle *Sound::replaceBackground(uint16 id, uint16 volume) {
+	debug (0, "Replacing background %d", id);
+
+	//TODO: The original engine does fading
+
+	Common::String name = _vm->getResourceName(ID_MSND, id);
+
+	// Check if sound is already playing
+	for (uint32 i = 0; i < _handles.size(); i++)
+		if (_handles[i].type == kBackgroundHandle
+				&& _vm->_mixer->isSoundHandleActive(_handles[i].handle)
+				&& name.equals(_vm->getResourceName(ID_MSND, _handles[i].id)))
+			return &_handles[i].handle;
+
+	// Stop old background sound
+	stopBackground();
+
+	// Play new sound
+	Audio::AudioStream *audStream = makeAudioStream(id);
+
+	if (audStream) {
+		SndHandle *handle = getHandle();
+		handle->type = kBackgroundHandle;
+		handle->id = id;
+
+		// Set the stream to loop
+		audStream = Audio::makeLoopingAudioStream((Audio::RewindableAudioStream *)audStream, 0);
+
+		_vm->_mixer->playStream(Audio::Mixer::kPlainSoundType, &handle->handle, audStream, -1, volume >> 8);
+		return &handle->handle;
+	}
+
+	return NULL;
+}
+
+void Sound::stopBackground() {
+	for (uint32 i = 0; i < _handles.size(); i++)
+		if (_handles[i].type == kBackgroundHandle) {
+			_vm->_mixer->stopHandle(_handles[i].handle);
+			_handles[i].type = kFreeHandle;
+			_handles[i].id = 0;
+		}
+}
+
+void Sound::pauseBackground() {
+	for (uint32 i = 0; i < _handles.size(); i++)
+		if (_handles[i].type == kBackgroundHandle)
+			_vm->_mixer->pauseHandle(_handles[i].handle, true);
+}
+
+void Sound::resumeBackground() {
+	for (uint32 i = 0; i < _handles.size(); i++)
+		if (_handles[i].type == kBackgroundHandle)
+			_vm->_mixer->pauseHandle(_handles[i].handle, false);
+}
+
+void Sound::changeBackgroundVolume(uint16 vol) {
+	for (uint32 i = 0; i < _handles.size(); i++)
+		if (_handles[i].type == kBackgroundHandle)
+			_vm->_mixer->setChannelVolume(_handles[i].handle, vol >> 8);
+}
+
 } // End of namespace Mohawk
diff --git a/engines/mohawk/sound.h b/engines/mohawk/sound.h
index 2d3edad557..daadd765eb 100644
--- a/engines/mohawk/sound.h
+++ b/engines/mohawk/sound.h
@@ -59,7 +59,8 @@ struct SLSTRecord {
 
 enum SndHandleType {
 	kFreeHandle,
-	kUsedHandle
+	kUsedHandle,
+	kBackgroundHandle
 };
 
 struct SndHandle {
@@ -129,10 +130,12 @@ public:
 	void resumeSound();
 	bool isPlaying(uint16 id);
 
-	void pauseBackground() {} //TODO: implement
-	void replaceBackground(uint16 id, uint16 volume) {}
-	void resumeBackground() {}
-	void stopBackground() {}
+	// Myst background sound functions
+	Audio::SoundHandle *replaceBackground(uint16 id, uint16 volume = 0xFFFF);
+	void pauseBackground();
+	void resumeBackground();
+	void stopBackground();
+	void changeBackgroundVolume(uint16 vol);
 
 	// Riven-specific
 	void playSLST(uint16 index, uint16 card);
@@ -153,6 +156,7 @@ private:
 
 	Common::Array<SndHandle> _handles;
 	SndHandle *getHandle();
+	Audio::AudioStream *makeAudioStream(uint16 id);
 
 	// Riven-specific
 	void playSLSTSound(uint16 index, bool fade, bool loop, uint16 volume, int16 balance);