Keep count of the number of samples played

Alc/ALc.c

@@ -1453,6 +1453,7 @@ ALC_API ALCcontext* ALC_APIENTRY alcCreateContext(ALCdevice *device, const ALCin
 {
     ALCcontext *ALContext;
     ALboolean running;
+    ALuint oldRate;
     ALuint attrIdx;
     void *temp;
     ALuint i;
@@ -1467,6 +1468,7 @@ ALC_API ALCcontext* ALC_APIENTRY alcCreateContext(ALCdevice *device, const ALCin
     }
 
     running = ((device->NumContexts > 0) ? AL_TRUE : AL_FALSE);
+    oldRate = device->Frequency;
 
     // Reset Context Last Error code
     device->LastError = ALC_NO_ERROR;
@@ -1540,6 +1542,11 @@ ALC_API ALCcontext* ALC_APIENTRY alcCreateContext(ALCdevice *device, const ALCin
     }
     aluInitPanning(device);
 
+    // Scale the number of samples played according to the new sample rate
+    device->SamplesPlayed *= device->Frequency;
+    device->SamplesPlayed += oldRate-1;
+    device->SamplesPlayed /= oldRate;
+
     for(i = 0;i < device->NumContexts;i++)
     {
         ALCcontext *context = device->Contexts[i];
@@ -1986,6 +1993,8 @@ ALC_API ALCdevice* ALC_APIENTRY alcOpenDevice(const ALCchar *deviceName)
     device->Contexts = NULL;
     device->NumContexts = 0;
 
+    device->SamplesPlayed = 0;
+
     InitUIntMap(&device->BufferMap);
     InitUIntMap(&device->EffectMap);
     InitUIntMap(&device->FilterMap);

Alc/ALu.c

@@ -1474,6 +1474,7 @@ ALvoid aluMixData(ALCdevice *device, ALvoid *buffer, ALsizei size)
             }
             ProcessContext(ALContext);
         }
+        device->SamplesPlayed += SamplesToDo;
         ProcessContext(NULL);
 
         //Post processing loop

OpenAL32/Include/alMain.h

@@ -405,6 +405,9 @@ struct ALCdevice_struct
     ALCcontext  **Contexts;
     ALuint        NumContexts;
 
+    // Number of samples rendered by this device
+    ALuint64      SamplesPlayed;
+
     BackendFuncs *Funcs;
     void         *ExtraData; // For the backend's use