Sound API: Add fading sounds

1 files changed, 20 insertions, 8 deletions

diff --git a/src/sound.h b/src/sound.h
index 98f7692d5..7bdb6a26b 100644
--- a/src/sound.h
+++ b/src/sound.h
@@ -34,8 +34,8 @@ public:
 
 struct SimpleSoundSpec
 {
-	SimpleSoundSpec(const std::string &name = "", float gain = 1.0)
-	    : name(name), gain(gain)
+	SimpleSoundSpec(const std::string &name = "", float gain = 1.0, float fade = 0.0)
+	    : name(name), gain(gain), fade(fade)
 	{
 	}
 
@@ -43,13 +43,13 @@ struct SimpleSoundSpec
 
 	std::string name;
 	float gain;
+	float fade;
 };
 
 class ISoundManager
 {
 public:
 	virtual ~ISoundManager() {}
-
 	// Multiple sounds can be loaded per name; when played, the sound
 	// should be chosen randomly from alternatives
 	// Return value determines success/failure
@@ -63,16 +63,21 @@ public:
 
 	// playSound functions return -1 on failure, otherwise a handle to the
 	// sound. If name=="", call should be ignored without error.
-	virtual int playSound(const std::string &name, bool loop, float volume) = 0;
-	virtual int playSoundAt(
-			const std::string &name, bool loop, float volume, v3f pos) = 0;
+	virtual int playSound(const std::string &name, bool loop, float volume,
+			float fade = 0) = 0;
+	virtual int playSoundAt(const std::string &name, bool loop, float volume,
+			v3f pos) = 0;
 	virtual void stopSound(int sound) = 0;
 	virtual bool soundExists(int sound) = 0;
 	virtual void updateSoundPosition(int sound, v3f pos) = 0;
+	virtual bool updateSoundGain(int id, float gain) = 0;
+	virtual float getSoundGain(int id) = 0;
+	virtual void step(float dtime) = 0;
+	virtual void fadeSound(int sound, float step, float gain) = 0;
 
 	int playSound(const SimpleSoundSpec &spec, bool loop)
 	{
-		return playSound(spec.name, loop, spec.gain);
+		return playSound(spec.name, loop, spec.gain, spec.fade);
 	}
 	int playSoundAt(const SimpleSoundSpec &spec, bool loop, v3f pos)
 	{
@@ -93,7 +98,10 @@ public:
 	}
 	void updateListener(v3f pos, v3f vel, v3f at, v3f up) {}
 	void setListenerGain(float gain) {}
-	int playSound(const std::string &name, bool loop, float volume) { return 0; }
+	int playSound(const std::string &name, bool loop, float volume, float fade)
+	{
+		return 0;
+	}
 	int playSoundAt(const std::string &name, bool loop, float volume, v3f pos)
 	{
 		return 0;
@@ -101,6 +109,10 @@ public:
 	void stopSound(int sound) {}
 	bool soundExists(int sound) { return false; }
 	void updateSoundPosition(int sound, v3f pos) {}
+	bool updateSoundGain(int id, float gain) { return false; }
+	float getSoundGain(int id) { return 0; }
+	void step(float dtime) { }
+	void fadeSound(int sound, float step, float gain) { }
 };
 
 // Global DummySoundManager singleton