Move the stereo-to-binaural filter to the device

Alc/ALc.c

@@ -534,8 +534,6 @@ ALCcontext *GetContextSuspended(void)
 */
 static ALvoid InitContext(ALCcontext *pContext)
 {
-    int level;
-
     //Initialise listener
     pContext->Listener.Gain = 1.0f;
     pContext->Listener.MetersPerUnit = 1.0f;
@@ -567,14 +565,6 @@ static ALvoid InitContext(ALCcontext *pContext)
 
     pContext->ExtensionList = "AL_EXTX_buffer_sub_data AL_EXT_EXPONENT_DISTANCE AL_EXT_FLOAT32 AL_EXT_IMA4 AL_EXT_LINEAR_DISTANCE AL_EXT_MCFORMATS AL_EXT_OFFSET AL_EXTX_sample_buffer_object AL_EXTX_source_distance_model AL_LOKI_quadriphonic";
 
-    level = GetConfigValueInt(NULL, "cf_level", 0);
-    if(level > 0 && level <= 6)
-    {
-        pContext->bs2b = calloc(1, sizeof(*pContext->bs2b));
-        bs2b_set_srate(pContext->bs2b, pContext->Frequency);
-        bs2b_set_level(pContext->bs2b, level);
-    }
-
     aluInitPanning(pContext);
 }
 
@@ -589,9 +579,6 @@ static ALCvoid ExitContext(ALCcontext *pContext)
     //Invalidate context
     pContext->LastError = AL_NO_ERROR;
     pContext->InUse = AL_FALSE;
-
-    free(pContext->bs2b);
-    pContext->bs2b = NULL;
 }
 
 ///////////////////////////////////////////////////////
@@ -1174,6 +1161,7 @@ ALCAPI ALCcontext* ALCAPIENTRY alcCreateContext(ALCdevice *device, const ALCint
             // Check for attributes
             if (attrList)
             {
+                ALCint level = device->Bs2bLevel;
                 ALCuint freq = device->Frequency;
                 ALCint numMono = device->lNumMonoSources;
                 ALCint numStereo = device->lNumStereoSources;
@@ -1213,12 +1201,22 @@ ALCAPI ALCcontext* ALCAPIENTRY alcCreateContext(ALCdevice *device, const ALCint
                     ulAttributeIndex += 2;
                 }
 
+                device->Bs2bLevel = GetConfigValueInt(NULL, "cf_level", level);
                 device->Frequency = GetConfigValueInt(NULL, "frequency", freq);
                 device->lNumMonoSources = numMono;
                 device->lNumStereoSources = numStereo;
                 device->NumAuxSends = numSends;
             }
 
+            free(device->Bs2b);
+            device->Bs2b = NULL;
+            if(device->Bs2bLevel > 0 && device->Bs2bLevel <= 6)
+            {
+                device->Bs2b = calloc(1, sizeof(*device->Bs2b));
+                bs2b_set_srate(device->Bs2b, device->Frequency);
+                bs2b_set_level(device->Bs2b, device->Bs2bLevel);
+            }
+
             if(ALCdevice_StartContext(device, ALContext) == ALC_FALSE)
             {
                 alcDestroyContext(ALContext);
@@ -1476,6 +1474,7 @@ ALCAPI ALCdevice* ALCAPIENTRY alcOpenDevice(const ALCchar *deviceName)
         device->Connected = ALC_TRUE;
         device->IsCaptureDevice = AL_FALSE;
 
+        device->Bs2b = NULL;
         device->szDeviceName = NULL;
 
         //Set output format
@@ -1505,6 +1504,8 @@ ALCAPI ALCdevice* ALCAPIENTRY alcOpenDevice(const ALCchar *deviceName)
         if(device->NumAuxSends > MAX_SENDS)
             device->NumAuxSends = MAX_SENDS;
 
+        device->Bs2bLevel = GetConfigValueInt(NULL, "cf_level", 0);
+
         // Find a playback device to open
         SuspendContext(NULL);
         for(i = 0;BackendList[i].Init;i++)
@@ -1598,6 +1599,9 @@ ALCAPI ALCboolean ALCAPIENTRY alcCloseDevice(ALCdevice *pDevice)
             ReleaseALDatabuffers(pDevice);
         }
 
+        free(pDevice->Bs2b);
+        pDevice->Bs2b = NULL;
+
         free(pDevice->szDeviceName);
 
         //Release device structure

Alc/ALu.c

@@ -1258,14 +1258,14 @@ ALvoid aluMixData(ALCcontext *ALContext,ALvoid *buffer,ALsizei size,ALenum forma
             }                                                                 \
             break;                                                            \
         case AL_FORMAT_STEREO##bits:                                          \
-            if(ALContext && ALContext->bs2b)                                  \
+            if(ALContext && ALContext->Device->Bs2b)                          \
             {                                                                 \
                 for(i = 0;i < SamplesToDo;i++)                                \
                 {                                                             \
                     float samples[2];                                         \
                     samples[0] = DryBuffer[i][FRONT_LEFT];                    \
                     samples[1] = DryBuffer[i][FRONT_RIGHT];                   \
-                    bs2b_cross_feed(ALContext->bs2b, samples);                \
+                    bs2b_cross_feed(ALContext->Device->Bs2b, samples);        \
                     ((type*)buffer)[0] = (func)(samples[0]);                  \
                     ((type*)buffer)[1] = (func)(samples[1]);                  \
                     buffer = ((type*)buffer) + 2;                             \

OpenAL32/Include/alMain.h

@@ -240,6 +240,10 @@ struct ALCdevice_struct
     struct ALdatabuffer *Databuffers;
     ALuint              DatabufferCount;
 
+    // Stereo-to-binaural filter
+    struct bs2b *Bs2b;
+    ALCint       Bs2bLevel;
+
     // Context created on this device
     ALCcontext   *Context;
 
@@ -292,8 +296,6 @@ struct ALCcontext_struct
     ALCdevice  *Device;
     const ALCchar *ExtensionList;
 
-    struct bs2b *bs2b;
-
     ALCcontext *next;
 };