MOHAWK: Add a Riven specific sound manager

- Add ambient sound fading
- Fix ambient sound volume to use the list-level volume

1 files changed, 197 insertions, 0 deletions

diff --git a/engines/mohawk/riven_sound.h b/engines/mohawk/riven_sound.h
new file mode 100644
index 0000000000..f673d1ee3f
--- /dev/null
+++ b/engines/mohawk/riven_sound.h
@@ -0,0 +1,197 @@
+/* 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.
+ *
+ */
+
+#ifndef MOHAWK_RIVEN_SOUND_H
+#define MOHAWK_RIVEN_SOUND_H
+
+#include "common/array.h"
+#include "common/str.h"
+
+#include "audio/mixer.h"
+
+namespace Audio {
+class RewindableAudioStream;
+}
+
+namespace Mohawk {
+
+class MohawkEngine;
+class RivenSound;
+
+/**
+ * Ambient sound list
+ */
+struct SLSTRecord {
+	uint16 index;
+	Common::Array<uint16> soundIds;
+	uint16 fadeFlags;
+	uint16 loop;
+	uint16 globalVolume;
+	uint16 u0;
+	uint16 suspend;
+	Common::Array<uint16> volumes;
+	Common::Array<int16> balances;
+	Common::Array<uint16> u2;
+};
+
+/**
+ * Sound manager for Riven
+ *
+ * The sound manager can play simulteaneously:
+ * - An effect sound
+ * - A list of ambient sounds
+ *
+ * The list of ambient sounds can be cross faded
+ * with the previously running ambient sounds.
+ */
+class RivenSoundManager {
+public:
+	RivenSoundManager(MohawkEngine *vm);
+	~RivenSoundManager();
+
+	/**
+	 * Play an effect sound
+	 * 
+	 * @param id Sound ID in the stack
+	 * @param volume Playback volume, between 0 and 255
+	 * @param playOnDraw Start playing when the current card is drawn instead of immediatly
+	 */
+	void playSound(uint16 id, uint16 volume = 255, bool playOnDraw = false);
+
+	/** Start playing the scheduled on-draw effect sound, if any. Called by the GraphicsManager. */
+	void triggerDrawSound();
+
+	/** Stop playing the current effect sound, if any */
+	void stopSound();
+
+	/** Start playing an ambient sound list */
+	void playSLST(const SLSTRecord &slstRecord);
+
+	/** Start playing an ambient sound list from a resource */
+	void playSLST(uint16 index, uint16 card);
+
+	/** Stop playing the current ambient sounds */
+	void stopAllSLST(bool fade = false);
+
+	/** Update the ambient sounds for fading. Called once per frame. */
+	void updateSLST();
+
+private:
+	struct AmbientSound {
+		RivenSound *sound;
+		uint16 targetVolume;
+		int16 targetBalance;
+
+		AmbientSound();
+	};
+
+	struct AmbientSoundList {
+		bool fading;
+		bool suspend;
+		Common::Array<AmbientSound> sounds;
+
+		AmbientSoundList();
+	};
+
+	enum FadeFlags {
+		kFadeOutPreviousSounds = 1,
+		kFadeInNewSounds = 2
+	};
+
+	MohawkEngine *_vm;
+
+	int16 _mainAmbientSoundId;
+	AmbientSoundList _ambientSounds;
+	AmbientSoundList _previousAmbientSounds;
+	uint32 _nextFadeUpdate;
+
+	RivenSound *_effect;
+	bool _effectPlayOnDraw;
+
+	Audio::RewindableAudioStream *makeAudioStream(uint16 id);
+
+	// Ambient sound management
+	void addAmbientSounds(const SLSTRecord &record);
+	void playAmbientSounds();
+	void pauseAmbientSounds();
+	void moveAmbientSoundsToPreviousSounds();
+	void freePreviousAmbientSounds();
+
+	// Ambient sound fading
+	void setTargetVolumes(const SLSTRecord &record);
+	void applyTargetVolumes();
+	void startFadingAmbientSounds(uint16 flags);
+	void fadeAmbientSoundList(AmbientSoundList &list);
+	bool fadeVolume(AmbientSound &ambientSound);
+	bool fadeBalance(AmbientSound &ambientSound);
+	void setAmbientLooping(bool loop);
+};
+
+/**
+ * A sound used internally by the SoundManager
+ */
+class RivenSound {
+public:
+	RivenSound(MohawkEngine *vm, Audio::RewindableAudioStream *rewindStream);
+	~RivenSound();
+
+	/** Start playing the sound stream passed to the constructor */
+	void play();
+
+	/** Is the sound currently playing ar paused? */
+	bool isPlaying() const;
+
+	/** Pause the playback, the play method resumes */
+	void pause();
+
+	/** Get the current volume */
+	uint16 getVolume() const;
+
+	/** Change the playback volume */
+	void setVolume(uint16 volume);
+
+	/** Get the current balance */
+	int16 getBalance() const;
+
+	/** Change the balance */
+	void setBalance(int16 balance);
+
+	/** Set the sound to indefinitely loop. Must be called before startting the playback */
+	void setLooping(bool loop);
+
+private:
+	static byte convertVolume(uint16 volume);
+	static int8 convertBalance(int16 balance);
+
+	MohawkEngine *_vm;
+
+	Audio::SoundHandle _handle;
+	Audio::RewindableAudioStream *_stream;
+
+	uint16 _volume;
+	int16 _balance;
+	bool _looping;
+};
+
+} // End of namespace Mohawk
+
+#endif