Add method to get device index if using system default mode.

Source/Engine/Audio/Audio.cpp

@@ -120,6 +120,20 @@ int32 Audio::GetActiveDeviceIndex()
     return ActiveDeviceIndex;
 }
 
+int32 Audio::GetActiveDeviceResolvedIndex()
+{
+    AudioDevice* active = GetActiveDevice();
+    if (active != nullptr)
+    {
+        for (int32 i = 0; i < Devices.Count(); i++)
+        {
+            if (&Devices[i] == active)
+                return i;
+        }
+    }
+    return -1;
+}
+
 void Audio::SetActiveDeviceIndex(int32 index)
 {
     index = Math::Clamp(index, -1, Devices.Count() - 1);

Source/Engine/Audio/Audio.h

@@ -61,11 +61,17 @@ public:
     API_PROPERTY() static AudioDevice* GetActiveDevice();
 
     /// <summary>
-    /// Gets the index of the active device.
+    /// Gets the index of the active device. Returns -1 if set to system default mode.
     /// </summary>
     /// <returns>The active device index.</returns>
     API_PROPERTY() static int32 GetActiveDeviceIndex();
 
+    /// <summary>
+    /// Gets the resolved index in Devices array of the device currently playing (resolves system default mode to the actual device index).
+    /// </summary>
+    /// <returns>The resolved active device index.</returns>
+    API_PROPERTY() static int32 GetActiveDeviceResolvedIndex();
+
     /// <summary>
     /// Sets the index of the active device.
     /// </summary>