- Add more parameters to the ambient sound things:

* Second argument: Volume scalar. 0 and 128 are normal volume. (Where "normal" is whatever
    it was defined with in SNDINFO.) Other values scale it accordingly.
  * Third argument: Minimum distance before volume fading starts.
  * Fourth argument: Maximum distance at which the sound is audible. Setting either of these to 0
    will use whatever they were defined with in SNDINFO.

SVN r2214 (trunk)

src/s_advsound.cpp

@@ -1912,6 +1912,12 @@ private:
 
 IMPLEMENT_CLASS (AAmbientSound)
 
+//==========================================================================
+//
+// AmbientSound :: Serialize
+//
+//==========================================================================
+
 void AAmbientSound::Serialize (FArchive &arc)
 {
 	Super::Serialize (arc);
@@ -1948,6 +1954,11 @@ void AAmbientSound::Serialize (FArchive &arc)
 	}
 }
 
+//==========================================================================
+//
+// AmbientSound :: Tick
+//
+//==========================================================================
 
 void AAmbientSound::Tick ()
 {
@@ -1966,7 +1977,24 @@ void AAmbientSound::Tick ()
 
 	if (ambient->sound[0])
 	{
-		S_Sound(this, CHAN_BODY | loop, ambient->sound, ambient->volume, ambient->attenuation);
+		// The second argumens scales the ambient sound's volume.
+		// 0 and 128 are normal volume. The maximum volume level
+		// possible is always 1.
+		float volscale = args[1] == 0 ? 1 : args[1] / 128.f;
+		float usevol = clamp(ambient->volume * volscale, 0.f, 1.f);
+
+		// The third argument is the minimum distance for audible fading, and
+		// the fourth argument is the maximum distance for audibility. Setting
+		// either of these to 0 or setting  min distance > max distance will
+		// use the standard rolloff.
+		if ((args[2] | args[3]) == 0 || args[2] > args[3])
+		{
+			S_Sound(this, CHAN_BODY | loop, ambient->sound, usevol, ambient->attenuation);
+		}
+		else
+		{
+			S_SoundMinMaxDist(this, CHAN_BODY | loop, ambient->sound, usevol, float(args[2]), float(args[3]));
+		}
 		if (!loop)
 		{
 			SetTicker (ambient);
@@ -1982,6 +2010,11 @@ void AAmbientSound::Tick ()
 	}
 }
 
+//==========================================================================
+//
+// AmbientSound :: SetTicker
+//
+//==========================================================================
 
 void AAmbientSound::SetTicker (struct AmbientSound *ambient)
 {
@@ -2001,12 +2034,26 @@ void AAmbientSound::SetTicker (struct AmbientSound *ambient)
 	}
 }
 
+//==========================================================================
+//
+// AmbientSound :: BeginPlay
+//
+//==========================================================================
+
 void AAmbientSound::BeginPlay ()
 {
 	Super::BeginPlay ();
 	Activate (NULL);
 }
 
+//==========================================================================
+//
+// AmbientSound :: Activate
+//
+// Starts playing a sound (or does nothing of the sound is already playing).
+//
+//==========================================================================
+
 void AAmbientSound::Activate (AActor *activator)
 {
 	Super::Activate (activator);
@@ -2040,6 +2087,15 @@ void AAmbientSound::Activate (AActor *activator)
 	}
 }
 
+//==========================================================================
+//
+// AmbientSound :: Deactivate
+//
+// Stops playing CONTINUOUS sounds immediately. Also prevents further
+// occurrences of repeated sounds.
+//
+//==========================================================================
+
 void AAmbientSound::Deactivate (AActor *activator)
 {
 	Super::Deactivate (activator);

src/s_sound.cpp

@@ -108,7 +108,7 @@ static void CalcPosVel(int type, const AActor *actor, const sector_t *sector, co
 static void CalcSectorSoundOrg(const sector_t *sec, int channum, fixed_t *x, fixed_t *y, fixed_t *z);
 static void CalcPolyobjSoundOrg(const FPolyObj *poly, fixed_t *x, fixed_t *y, fixed_t *z);
 static FSoundChan *S_StartSound(AActor *mover, const sector_t *sec, const FPolyObj *poly,
-	const FVector3 *pt, int channel, FSoundID sound_id, float volume, float attenuation);
+	const FVector3 *pt, int channel, FSoundID sound_id, float volume, float attenuation, FRolloffInfo *rolloff);
 static void S_SetListener(SoundListener &listener, AActor *listenactor);
 
 // PRIVATE DATA DEFINITIONS ------------------------------------------------
@@ -808,7 +808,8 @@ static void CalcPolyobjSoundOrg(const FPolyObj *poly, fixed_t *x, fixed_t *y, fi
 //==========================================================================
 
 static FSoundChan *S_StartSound(AActor *actor, const sector_t *sec, const FPolyObj *poly,
-	const FVector3 *pt, int channel, FSoundID sound_id, float volume, float attenuation)
+	const FVector3 *pt, int channel, FSoundID sound_id, float volume, float attenuation,
+	FRolloffInfo *forcedrolloff=NULL)
 {
 	sfxinfo_t *sfx;
 	int chanflags;
@@ -894,7 +895,10 @@ static FSoundChan *S_StartSound(AActor *actor, const sector_t *sec, const FPolyO
 				near_limit = S_sfx[sound_id].NearLimit;
 				limit_range = S_sfx[sound_id].LimitRange;
 			}
-			if (rolloff->MinDistance == 0) rolloff = &S_sfx[sound_id].Rolloff;
+			if (rolloff->MinDistance == 0)
+			{
+				rolloff = &S_sfx[sound_id].Rolloff;
+			}
 		}
 		else
 		{
@@ -904,13 +908,25 @@ static FSoundChan *S_StartSound(AActor *actor, const sector_t *sec, const FPolyO
 				near_limit = S_sfx[sound_id].NearLimit;
 				limit_range = S_sfx[sound_id].LimitRange;
 			}
-			if (rolloff->MinDistance == 0) rolloff = &S_sfx[sound_id].Rolloff;
+			if (rolloff->MinDistance == 0)
+			{
+				rolloff = &S_sfx[sound_id].Rolloff;
+			}
 		}
 		sfx = &S_sfx[sound_id];
 	}
 
-	// If no valid rolloff was set use the global default
+	// The passed rolloff overrides any sound-specific rolloff.
-	if (rolloff->MinDistance == 0) rolloff = &S_Rolloff;
+	if (forcedrolloff != NULL && forcedrolloff->MinDistance != 0)
+	{
+		rolloff = forcedrolloff;
+	}
+
+	// If no valid rolloff was set, use the global default.
+	if (rolloff->MinDistance == 0)
+	{
+		rolloff = &S_Rolloff;
+	}
 
 	// If this is a singular sound, don't play it if it's already playing.
 	if (sfx->bSingular && S_CheckSingular(sound_id))
@@ -1180,6 +1196,27 @@ void S_Sound (AActor *ent, int channel, FSoundID sound_id, float volume, float a
 	S_StartSound (ent, NULL, NULL, NULL, channel, sound_id, volume, attenuation);
 }
 
+//==========================================================================
+//
+// S_SoundMinMaxDist - An actor is source
+//
+// Attenuation is specified as min and max distances, rather than a scalar.
+//
+//==========================================================================
+
+void S_SoundMinMaxDist(AActor *ent, int channel, FSoundID sound_id, float volume, float mindist, float maxdist)
+{
+	if (ent == NULL || ent->Sector->Flags & SECF_SILENT)
+		return;
+
+	FRolloffInfo rolloff;
+
+	rolloff.RolloffType = ROLLOFF_Doom;
+	rolloff.MinDistance = mindist;
+	rolloff.MaxDistance = maxdist;
+	S_StartSound(ent, NULL, NULL, NULL, channel, sound_id, volume, 1, &rolloff);
+}
+
 //==========================================================================
 //
 // S_Sound - A polyobject is source

src/s_sound.h

@@ -218,6 +218,7 @@ void S_CacheSound (sfxinfo_t *sfx);
 // Start sound for thing at <ent>
 void S_Sound (int channel, FSoundID sfxid, float volume, float attenuation);
 void S_Sound (AActor *ent, int channel, FSoundID sfxid, float volume, float attenuation);
+void S_SoundMinMaxDist (AActor *ent, int channel, FSoundID sfxid, float volume, float mindist, float maxdist);
 void S_Sound (const FPolyObj *poly, int channel, FSoundID sfxid, float volume, float attenuation);
 void S_Sound (const sector_t *sec, int channel, FSoundID sfxid, float volume, float attenuation);
 void S_Sound (fixed_t x, fixed_t y, fixed_t z, int channel, FSoundID sfxid, float volume, float attenuation);