Add a global option to apply a reverb effect on source send 0

A special slot on the device is created and processed, so it can be shared
across all contexts on the device. Sources that don't have a slot set on send 0
will use this special slot instead.

Alc/ALc.c

@@ -399,6 +399,9 @@ static ALCboolean TrapALCError = ALC_FALSE;
 /* One-time configuration init control */
 static pthread_once_t alc_config_once = PTHREAD_ONCE_INIT;
 
+/* Forced effect that applies to sources that don't have an effect on send 0 */
+static ALeffect ForcedEffect;
+
 ///////////////////////////////////////////////////////
 
 
@@ -718,6 +721,10 @@ static void alc_initconfig(void)
             }
         } while(next++);
     }
+
+    str = getenv("__ALSOFT_FORCE_REVERB");
+    if(str && str[0])
+        GetReverbEffect(&ForcedEffect);
 }
 
 
@@ -1296,6 +1303,9 @@ static ALCvoid FreeDevice(ALCdevice *device)
 {
     TRACE("%p\n", device);
 
+    ALeffectState_Destroy(device->DefaultSlot->EffectState);
+    device->DefaultSlot->EffectState = NULL;
+
     if(device->BufferMap.size > 0)
     {
         WARN("(%p) Deleting %d Buffer(s)\n", device, device->BufferMap.size);
@@ -2236,6 +2246,8 @@ ALC_API ALCcontext* ALC_APIENTRY alcCreateContext(ALCdevice *device, const ALCin
     } while(!CompExchangePtr((XchgPtr*)&device->ContextList, ALContext->next, ALContext));
     UnlockLists();
 
+    InitializeEffect(ALContext, device->DefaultSlot, &ForcedEffect);
+
     ALCdevice_DecRef(device);
 
     TRACE("Created context %p\n", ALContext);
@@ -2414,6 +2426,7 @@ ALC_API ALCdevice* ALC_APIENTRY alcOpenDevice(const ALCchar *deviceName)
     const ALCchar *fmt;
     ALCdevice *device;
     ALCenum err;
+    ALCint i;
 
     DO_INITCONFIG();
 
@@ -2426,7 +2439,7 @@ ALC_API ALCdevice* ALC_APIENTRY alcOpenDevice(const ALCchar *deviceName)
     if(deviceName && (!deviceName[0] || strcasecmp(deviceName, "openal soft") == 0 || strcasecmp(deviceName, "openal-soft") == 0))
         deviceName = NULL;
 
-    device = calloc(1, sizeof(ALCdevice));
+    device = calloc(1, sizeof(ALCdevice)+sizeof(ALeffectslot));
     if(!device)
     {
         alcSetError(NULL, ALC_OUT_OF_MEMORY);
@@ -2491,6 +2504,20 @@ ALC_API ALCdevice* ALC_APIENTRY alcOpenDevice(const ALCchar *deviceName)
     device->NumStereoSources = 1;
     device->NumMonoSources = device->MaxNoOfSources - device->NumStereoSources;
 
+    device->DefaultSlot = (ALeffectslot*)(device+1);
+    device->DefaultSlot->EffectState = NoneCreate();
+    device->DefaultSlot->Gain = 1.0;
+    device->DefaultSlot->AuxSendAuto = AL_TRUE;
+    device->DefaultSlot->NeedsUpdate = AL_FALSE;
+    for(i = 0;i < BUFFERSIZE;i++)
+        device->DefaultSlot->WetBuffer[i] = 0.0f;
+    for(i = 0;i < 1;i++)
+    {
+        device->DefaultSlot->ClickRemoval[i] = 0.0f;
+        device->DefaultSlot->PendingClicks[i] = 0.0f;
+    }
+    device->DefaultSlot->ref = 0;
+
     // Find a playback device to open
     LockLists();
     if((err=ALCdevice_OpenPlayback(device, deviceName)) != ALC_NO_ERROR)

Alc/ALu.c

@@ -293,7 +293,11 @@ ALvoid CalcNonAttnSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
     }
     for(i = 0;i < NumSends;i++)
     {
-        ALSource->Params.Send[i].Slot = ALSource->Send[i].Slot;
+        ALeffectslot *Slot = ALSource->Send[i].Slot;
+
+        if(!Slot && i == 0)
+            Slot = Device->DefaultSlot;
+        ALSource->Params.Send[i].Slot = Slot;
         ALSource->Params.Send[i].WetGain = WetGain[i] * ListenerGain;
     }
 
@@ -392,6 +396,8 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
     {
         ALeffectslot *Slot = ALSource->Send[i].Slot;
 
+        if(!Slot && i == 0)
+            Slot = Device->DefaultSlot;
         if(!Slot || Slot->effect.type == AL_EFFECT_NULL)
         {
             RoomRolloff[i] = 0.0f;
@@ -978,6 +984,24 @@ ALvoid aluMixData(ALCdevice *device, ALvoid *buffer, ALsizei size)
 
             ctx = ctx->next;
         }
+
+        slot = &device->DefaultSlot;
+        for(c = 0;c < SamplesToDo;c++)
+        {
+            (*slot)->WetBuffer[c] += (*slot)->ClickRemoval[0];
+            (*slot)->ClickRemoval[0] -= (*slot)->ClickRemoval[0] * (1.0f/256.0f);
+        }
+        (*slot)->ClickRemoval[0] += (*slot)->PendingClicks[0];
+        (*slot)->PendingClicks[0] = 0.0f;
+
+        if(ExchangeInt(&(*slot)->NeedsUpdate, AL_FALSE))
+            ALeffectState_Update((*slot)->EffectState, ctx, *slot);
+
+        ALeffectState_Process((*slot)->EffectState, SamplesToDo,
+                              (*slot)->WetBuffer, device->DryBuffer);
+
+        for(i = 0;i < SamplesToDo;i++)
+            (*slot)->WetBuffer[i] = 0.0f;
         UnlockDevice(device);
 
         //Post processing loop

OpenAL32/Include/alAuxEffectSlot.h

@@ -35,6 +35,7 @@ typedef struct ALeffectslot
 } ALeffectslot;
 
 
+ALvoid InitializeEffect(ALCcontext *Context, ALeffectslot *EffectSlot, ALeffect *effect);
 ALvoid ReleaseALAuxiliaryEffectSlots(ALCcontext *Context);
 
 

OpenAL32/Include/alEffect.h

@@ -102,6 +102,7 @@ typedef struct ALeffect
 static __inline ALboolean IsReverbEffect(ALenum type)
 { return type == AL_EFFECT_REVERB || type == AL_EFFECT_EAXREVERB; }
 
+ALvoid GetReverbEffect(ALeffect *effect);
 ALvoid ReleaseALEffects(ALCdevice *device);
 
 #ifdef __cplusplus

OpenAL32/Include/alMain.h

@@ -598,6 +598,9 @@ struct ALCdevice_struct
     ALfloat ClickRemoval[MAXCHANNELS];
     ALfloat PendingClicks[MAXCHANNELS];
 
+    /* Default effect slot */
+    struct ALeffectslot *DefaultSlot;
+
     // Contexts created on this device
     ALCcontext *volatile ContextList;
 

OpenAL32/alAuxEffectSlot.c

@@ -32,7 +32,6 @@
 #include "alSource.h"
 
 
-static ALvoid InitializeEffect(ALCcontext *Context, ALeffectslot *EffectSlot, ALeffect *effect);
 static ALenum ResizeEffectSlotArray(ALCcontext *Context, ALsizei count);
 static ALvoid RemoveEffectSlotArray(ALCcontext *Context, ALeffectslot *val);
 
@@ -512,7 +511,7 @@ static ALenum ResizeEffectSlotArray(ALCcontext *Context, ALsizei count)
     return AL_NO_ERROR;
 }
 
-static ALvoid InitializeEffect(ALCcontext *Context, ALeffectslot *EffectSlot, ALeffect *effect)
+ALvoid InitializeEffect(ALCcontext *Context, ALeffectslot *EffectSlot, ALeffect *effect)
 {
     ALenum newtype = (effect ? effect->type : AL_EFFECT_NULL);
     ALeffectState *State = NULL;

OpenAL32/alEffect.c

@@ -1306,3 +1306,9 @@ static void InitEffectParams(ALeffect *effect, ALenum type)
     }
     effect->type = type;
 }
+
+
+ALvoid GetReverbEffect(ALeffect *effect)
+{
+    InitEffectParams(effect, AL_EFFECT_EAXREVERB);
+}