Use a macro to specify the decay target gain

3 files changed, 10 insertions, 7 deletions

diff --git a/Alc/ALu.c b/Alc/ALu.c
index c27617f5..22aca28a 100644
--- a/Alc/ALu.c
+++ b/Alc/ALu.c
@@ -1098,8 +1098,8 @@ static void CalcAttnSourceParams(ALvoice *voice, const struct ALvoiceProps *prop
             RoomAirAbsorption[i] = SendSlots[i]->Params.AirAbsorptionGainHF;
             if(SendSlots[i]->Params.DecayHFLimit && RoomAirAbsorption[i] < 1.0f)
             {
-                ALfloat limitRatio = log10f(0.001f)/*-60 dB*/ / (log10f(RoomAirAbsorption[i]) *
-                                                                 DecayDistance[i]);
+                ALfloat limitRatio = log10f(REVERB_DECAY_GAIN) /
+                                     (log10f(RoomAirAbsorption[i]) * DecayDistance[i]);
                 limitRatio = minf(limitRatio, SendSlots[i]->Params.DecayHFRatio);
                 DecayHFDistance[i] = minf(DecayHFDistance[i], limitRatio*DecayDistance[i]);
             }
@@ -1258,15 +1258,15 @@ static void CalcAttnSourceParams(ALvoice *voice, const struct ALvoiceProps *prop
                 if(!(DecayDistance[i] > 0.0f))
                     continue;
 
-                gain = powf(0.001f/*-60dB*/, meters_base/DecayDistance[i]);
+                gain = powf(REVERB_DECAY_GAIN, meters_base/DecayDistance[i]);
                 WetGain[i] *= gain;
                 /* Yes, the wet path's air absorption is applied with
                  * WetGainAuto on, rather than WetGainHFAuto.
                  */
                 if(gain > 0.0f)
                 {
-                    ALfloat gainhf = powf(0.001f/*-60dB*/, meters_base/DecayHFDistance[i]) / gain;
-                    WetGainHF[i] *= minf(gainhf, 1.0f);
+                    ALfloat gainhf = powf(REVERB_DECAY_GAIN, meters_base/DecayHFDistance[i]);
+                    WetGainHF[i] *= minf(gainhf / gain, 1.0f);
                 }
             }
         }
diff --git a/Alc/effects/reverb.c b/Alc/effects/reverb.c
index 0d0ca277..39daff53 100644
--- a/Alc/effects/reverb.c
+++ b/Alc/effects/reverb.c
@@ -645,7 +645,7 @@ static ALboolean ALreverbState_deviceUpdate(ALreverbState *State, ALCdevice *Dev
  */
 static inline ALfloat CalcDecayCoeff(const ALfloat length, const ALfloat decayTime)
 {
-    return powf(0.001f/*-60 dB*/, length/decayTime);
+    return powf(REVERB_DECAY_GAIN, length/decayTime);
 }
 
 /* Calculate a decay length from a coefficient and the time until the decay
@@ -653,7 +653,7 @@ static inline ALfloat CalcDecayCoeff(const ALfloat length, const ALfloat decayTi
  */
 static inline ALfloat CalcDecayLength(const ALfloat coeff, const ALfloat decayTime)
 {
-    return log10f(coeff) * decayTime / log10f(0.001f)/*-60 dB*/;
+    return log10f(coeff) * decayTime / log10f(REVERB_DECAY_GAIN);
 }
 
 /* Calculate an attenuation to be applied to the input of any echo models to
diff --git a/OpenAL32/Include/alu.h b/OpenAL32/Include/alu.h
index 30b245a5..c44f94d4 100644
--- a/OpenAL32/Include/alu.h
+++ b/OpenAL32/Include/alu.h
@@ -348,6 +348,9 @@ typedef void (*HrtfDirectMixerFunc)(ALfloat *restrict LeftOut, ALfloat *restrict
 #define SPEEDOFSOUNDMETRESPERSEC  (343.3f)
 #define AIRABSORBGAINHF           (0.99426f) /* -0.05dB */
 
+/* Target gain for the reverb decay feedback reaching the decay time. */
+#define REVERB_DECAY_GAIN  (0.001f) /* -60 dB */
+
 #define FRACTIONBITS (12)
 #define FRACTIONONE  (1<<FRACTIONBITS)
 #define FRACTIONMASK (FRACTIONONE-1)