Provide (mostly) lockless updates for effect slots

Similar to the listener, separate containers are provided atomically for the
mixer thread to apply updates without needing to block, and a free-list is used
to reuse container objects.

A couple things to note. First, the lock is still used when the effect state's
deviceUpdate method is called to prevent asynchronous calls to reset the device
from interfering. This can be fixed by using the list lock in ALc.c instead.

Secondly, old effect states aren't immediately deleted when the effect type
changes (the actual type, not just its properties). This is because the mixer
thread is intended to be real-time safe, and so can't be freeing anything. They
are cleared away when updates reuse the container they were kept in, and they
don't incur any extra processing cost, but there may be cases where the memory
is kept around until the effect slot is deleted.

1 files changed, 39 insertions, 5 deletions

diff --git a/OpenAL32/Include/alAuxEffectSlot.h b/OpenAL32/Include/alAuxEffectSlot.h
index e521ff82..7f670a95 100644
--- a/OpenAL32/Include/alAuxEffectSlot.h
+++ b/OpenAL32/Include/alAuxEffectSlot.h
@@ -20,6 +20,8 @@ typedef struct ALeffectState {
     ALuint OutChannels;
 } ALeffectState;
 
+void ALeffectState_Destruct(ALeffectState *state);
+
 struct ALeffectStateVtable {
     void (*const Destruct)(ALeffectState *state);
 
@@ -70,18 +72,48 @@ static const struct ALeffectStateFactoryVtable T##_ALeffectStateFactory_vtable =
 #define MAX_EFFECT_CHANNELS (4)
 
 
-typedef struct ALeffectslot {
-    ALenum EffectType;
-    ALeffectProps EffectProps;
+struct ALeffectslotProps {
+    ATOMIC(ALfloat)   Gain;
+    ATOMIC(ALboolean) AuxSendAuto;
+
+    ATOMIC(ALenum) Type;
+    ALeffectProps Props;
+
+    ATOMIC(ALeffectState*) State;
+
+    ATOMIC(struct ALeffectslotProps*) next;
+};
+
 
+typedef struct ALeffectslot {
     volatile ALfloat   Gain;
     volatile ALboolean AuxSendAuto;
 
-    ATOMIC(ALenum) NeedsUpdate;
-    ALeffectState *EffectState;
+    struct {
+        ALenum Type;
+        ALeffectProps Props;
+
+        ALeffectState *State;
+    } Effect;
 
     RefCount ref;
 
+    ATOMIC(struct ALeffectslotProps*) Update;
+    ATOMIC(struct ALeffectslotProps*) FreeList;
+
+    struct {
+        ALfloat   Gain;
+        ALboolean AuxSendAuto;
+
+        ALenum EffectType;
+        ALeffectProps EffectProps;
+        ALeffectState *EffectState;
+
+        ALfloat RoomRolloff; /* Added to the source's room rolloff, not multiplied. */
+        ALfloat DecayTime;
+        ALfloat AirAbsorptionGainHF;
+    } Params;
+
     /* Self ID */
     ALuint id;
 
@@ -106,6 +138,8 @@ inline struct ALeffectslot *RemoveEffectSlot(ALCcontext *context, ALuint id)
 { return (struct ALeffectslot*)RemoveUIntMapKey(&context->EffectSlotMap, id); }
 
 ALenum InitEffectSlot(ALeffectslot *slot);
+void DeinitEffectSlot(ALeffectslot *slot);
+void UpdateEffectSlotProps(ALeffectslot *slot);
 ALvoid ReleaseALAuxiliaryEffectSlots(ALCcontext *Context);