Implement AL_ROOM_ROLLOFF_FACTOR property

Alc/ALu.c

@@ -192,7 +192,9 @@ static ALvoid CalcSourceParams(ALCcontext *ALContext, ALsource *ALSource,
     ALfloat Matrix[3][3];
     ALint HeadRelative;
     ALfloat flAttenuation;
+    ALfloat RoomAttenuation;
     ALfloat MetersPerUnit;
+    ALfloat RoomRolloff;
     ALfloat DryGainHF = 1.0f;
     ALfloat WetGainHF = 1.0f;
 
@@ -226,6 +228,7 @@ static ALvoid CalcSourceParams(ALCcontext *ALContext, ALsource *ALSource,
     OuterAngle   = ALSource->flOuterAngle;
     HeadRelative = ALSource->bHeadRelative;
     OuterGainHF  = ALSource->OuterGainHF;
+    RoomRolloff  = ALSource->RoomRolloffFactor;
 
     //Only apply 3D calculations for mono buffers
     if(isMono != AL_FALSE)
@@ -242,6 +245,7 @@ static ALvoid CalcSourceParams(ALCcontext *ALContext, ALsource *ALSource,
         Distance = aluSqrt(aluDotproduct(Position, Position));
 
         flAttenuation = 1.0f;
+        RoomAttenuation = 1.0f;
         switch (DistanceModel)
         {
             case AL_INVERSE_DISTANCE_CLAMPED:
@@ -255,6 +259,8 @@ static ALvoid CalcSourceParams(ALCcontext *ALContext, ALsource *ALSource,
                 {
                     if ((MinDist + (Rolloff * (Distance - MinDist))) > 0.0f)
                         flAttenuation = MinDist / (MinDist + (Rolloff * (Distance - MinDist)));
+                    if ((MinDist + (RoomRolloff * (Distance - MinDist))) > 0.0f)
+                        RoomAttenuation = MinDist / (MinDist + (RoomRolloff * (Distance - MinDist)));
                 }
                 break;
 
@@ -267,7 +273,10 @@ static ALvoid CalcSourceParams(ALCcontext *ALContext, ALsource *ALSource,
             case AL_LINEAR_DISTANCE:
                 Distance=__min(Distance,MaxDist);
                 if (MaxDist != MinDist)
+                {
                     flAttenuation = 1.0f - (Rolloff*(Distance-MinDist)/(MaxDist - MinDist));
+                    RoomAttenuation = 1.0f - (RoomRolloff*(Distance-MinDist)/(MaxDist - MinDist));
+                }
                 break;
 
             case AL_EXPONENT_DISTANCE_CLAMPED:
@@ -278,18 +287,22 @@ static ALvoid CalcSourceParams(ALCcontext *ALContext, ALsource *ALSource,
                 //fall-through
             case AL_EXPONENT_DISTANCE:
                 if ((Distance > 0.0f) && (MinDist > 0.0f))
+                {
                     flAttenuation = (ALfloat)pow(Distance/MinDist, -Rolloff);
+                    RoomAttenuation = (ALfloat)pow(Distance/MinDist, -RoomRolloff);
+                }
                 break;
 
             case AL_NONE:
             default:
                 flAttenuation = 1.0f;
+                RoomAttenuation = 1.0f;
                 break;
         }
 
         // Source Gain + Attenuation
         DryMix = SourceVolume * flAttenuation;
-        WetMix = SourceVolume * 0.0f;
+        WetMix = SourceVolume * RoomAttenuation;
 
         // Clamp to Min/Max Gain
         DryMix = __min(DryMix,MaxVolume);

OpenAL32/Include/alSource.h

@@ -80,6 +80,8 @@ typedef struct ALsource_struct
 
     ALfloat AirAbsorptionFactor;
 
+    ALfloat RoomRolloffFactor;
+
     // Index to itself
     ALuint source;
 

OpenAL32/alSource.c

@@ -355,6 +355,13 @@ ALAPI ALvoid ALAPIENTRY alSourcef(ALuint source, ALenum eParam, ALfloat flValue)
                     alSetError(AL_INVALID_VALUE);
                 break;
 
+            case AL_ROOM_ROLLOFF_FACTOR:
+                if (flValue >= 0.0f && flValue <= 1.0f)
+                    pSource->RoomRolloffFactor = flValue;
+                else
+                    alSetError(AL_INVALID_VALUE);
+                break;
+
             case AL_SEC_OFFSET:
             case AL_SAMPLE_OFFSET:
             case AL_BYTE_OFFSET:
@@ -480,6 +487,7 @@ ALAPI ALvoid ALAPIENTRY alSourcefv(ALuint source, ALenum eParam, const ALfloat *
                 case AL_SAMPLE_OFFSET:
                 case AL_BYTE_OFFSET:
                 case AL_AIR_ABSORPTION_FACTOR:
+                case AL_ROOM_ROLLOFF_FACTOR:
                     alSourcef(source, eParam, pflValues[0]);
                     break;
 
@@ -901,6 +909,10 @@ ALAPI ALvoid ALAPIENTRY alGetSourcef(ALuint source, ALenum eParam, ALfloat *pflV
                     *pflValue = pSource->AirAbsorptionFactor;
                     break;
 
+                case AL_ROOM_ROLLOFF_FACTOR:
+                    *pflValue = pSource->RoomRolloffFactor;
+                    break;
+
                 default:
                     alSetError(AL_INVALID_ENUM);
                     break;
@@ -1010,6 +1022,7 @@ ALAPI ALvoid ALAPIENTRY alGetSourcefv(ALuint source, ALenum eParam, ALfloat *pfl
                 case AL_REFERENCE_DISTANCE:
                 case AL_CONE_OUTER_GAINHF:
                 case AL_AIR_ABSORPTION_FACTOR:
+                case AL_ROOM_ROLLOFF_FACTOR:
                     alGetSourcef(source, eParam, pflValues);
                     break;