Output on available channels only, for the echo and modulator effects

1 files changed, 15 insertions, 12 deletions

diff --git a/Alc/alcEcho.c b/Alc/alcEcho.c
index d6f7fbb3..e6ecac5c 100644
--- a/Alc/alcEcho.c
+++ b/Alc/alcEcho.c
@@ -49,7 +49,7 @@ typedef struct ALechoState {
 
     ALfloat FeedGain;
 
-    ALfloat Scale;
+    ALfloat Gain[OUTPUTCHANNELS];
 
     FILTER iirFilter;
     ALfloat history[2];
@@ -90,8 +90,13 @@ static ALboolean EchoDeviceUpdate(ALeffectState *effect, ALCdevice *Device)
     for(i = 0;i < state->BufferLength;i++)
         state->SampleBuffer[i] = 0.0f;
 
-    state->Scale = aluSqrt(Device->NumChan / 6.0f);
-    state->Scale = __min(state->Scale, 1.0f);
+    for(i = 0;i < OUTPUTCHANNELS;i++)
+        state->Gain[i] = 0.0f;
+    for(i = 0;i < Device->NumChan;i++)
+    {
+        Channel chan = Device->Speaker2Chan[i];
+        state->Gain[chan] = 1.0f;
+    }
 
     return AL_TRUE;
 }
@@ -127,7 +132,7 @@ static ALvoid EchoProcess(ALeffectState *effect, const ALeffectslot *Slot, ALuin
     const ALuint tap1 = state->Tap[0].delay;
     const ALuint tap2 = state->Tap[1].delay;
     ALuint offset = state->Offset;
-    const ALfloat gain = Slot->Gain * state->Scale;
+    const ALfloat gain = Slot->Gain;
     ALfloat samp[2], smp;
     ALuint i;
 
@@ -151,12 +156,12 @@ static ALvoid EchoProcess(ALeffectState *effect, const ALeffectslot *Slot, ALuin
         samp[0] *= gain;
         samp[1] *= gain;
 
-        SamplesOut[i][FRONT_LEFT]  += samp[0];
-        SamplesOut[i][FRONT_RIGHT] += samp[1];
-        SamplesOut[i][SIDE_LEFT]   += samp[0];
-        SamplesOut[i][SIDE_RIGHT]  += samp[1];
-        SamplesOut[i][BACK_LEFT]   += samp[0];
-        SamplesOut[i][BACK_RIGHT]  += samp[1];
+        SamplesOut[i][FRONT_LEFT]  += state->Gain[FRONT_LEFT]  * samp[0];
+        SamplesOut[i][FRONT_RIGHT] += state->Gain[FRONT_RIGHT] * samp[1];
+        SamplesOut[i][SIDE_LEFT]   += state->Gain[SIDE_LEFT]   * samp[0];
+        SamplesOut[i][SIDE_RIGHT]  += state->Gain[SIDE_RIGHT]  * samp[1];
+        SamplesOut[i][BACK_LEFT]   += state->Gain[BACK_LEFT]   * samp[0];
+        SamplesOut[i][BACK_RIGHT]  += state->Gain[BACK_RIGHT]  * samp[1];
     }
     state->Offset = offset;
 }
@@ -183,8 +188,6 @@ ALeffectState *EchoCreate(void)
     state->GainL = 0.0f;
     state->GainR = 0.0f;
 
-    state->Scale = 1.0f;
-
     state->iirFilter.coeff = 0.0f;
     state->iirFilter.history[0] = 0.0f;
     state->iirFilter.history[1] = 0.0f;