Add a new compressor/limiter

This is just for the output limiter right now, but in the future can be used
for the compressor EFX effect. The parameters are also hardcoded, but can be
made configurable after 1.18.

1 files changed, 17 insertions, 4 deletions

diff --git a/Alc/ALc.c b/Alc/ALc.c
index 0e821b35..dcda29c3 100644
--- a/Alc/ALc.c
+++ b/Alc/ALc.c
@@ -1738,6 +1738,12 @@ static void alcSetError(ALCdevice *device, ALCenum errorCode)
 }
 
 
+struct Compressor *CreateDeviceLimiter(const ALCdevice *device)
+{
+    return CompressorInit(0.0f, 0.0f, AL_FALSE, AL_TRUE, 0.0f, 0.0f, 0.5f, 2.0f,
+                          0.0f, -0.5f, 3.0f, device->Frequency);
+}
+
 /* UpdateClockBase
  *
  * Updates the device's base clock time with however many samples have been
@@ -2224,8 +2230,11 @@ static ALCenum UpdateDeviceParams(ALCdevice *device, const ALCint *attrList)
      */
     if(gainLimiter != ALC_FALSE)
     {
-        if(!device->Limiter)
-            device->Limiter = alloc_limiter();
+        if(!device->Limiter || device->Frequency != GetCompressorSampleRate(device->Limiter))
+        {
+            al_free(device->Limiter);
+            device->Limiter = CreateDeviceLimiter(device);
+        }
     }
     else
     {
@@ -3845,7 +3854,7 @@ ALC_API ALCdevice* ALC_APIENTRY alcOpenDevice(const ALCchar *deviceName)
     device->FOAOut.NumChannels = 0;
     device->RealOut.Buffer = NULL;
     device->RealOut.NumChannels = 0;
-    device->Limiter = alloc_limiter();
+    device->Limiter = NULL;
     device->AvgSpeakerDist = 0.0f;
 
     ATOMIC_INIT(&device->ContextList, NULL);
@@ -4021,6 +4030,8 @@ ALC_API ALCdevice* ALC_APIENTRY alcOpenDevice(const ALCchar *deviceName)
         alstr_get_cstr(device->DeviceName), NULL, "dither", 1
     );
 
+    device->Limiter = CreateDeviceLimiter(device);
+
     if(DefaultEffect.type != AL_EFFECT_NULL)
     {
         device->DefaultSlot = (ALeffectslot*)device->_slot_mem;
@@ -4378,7 +4389,7 @@ ALC_API ALCdevice* ALC_APIENTRY alcLoopbackOpenDeviceSOFT(const ALCchar *deviceN
     device->FOAOut.NumChannels = 0;
     device->RealOut.Buffer = NULL;
     device->RealOut.NumChannels = 0;
-    device->Limiter = alloc_limiter();
+    device->Limiter = NULL;
     device->AvgSpeakerDist = 0.0f;
 
     ATOMIC_INIT(&device->ContextList, NULL);
@@ -4441,6 +4452,8 @@ ALC_API ALCdevice* ALC_APIENTRY alcLoopbackOpenDeviceSOFT(const ALCchar *deviceN
 
     device->DitherEnabled = GetConfigValueBool(NULL, NULL, "dither", 1);
 
+    device->Limiter = CreateDeviceLimiter(device);
+
     {
         ALCdevice *head = ATOMIC_LOAD_SEQ(&DeviceList);
         do {