Update AL_EXTX_source_distance_model to require explicit enabling

The in-progress spec has been updated to reflect this

1 files changed, 1 insertions, 0 deletions

diff --git a/OpenAL32/Include/alMain.h b/OpenAL32/Include/alMain.h
index 2bcecf05..e235794a 100644
--- a/OpenAL32/Include/alMain.h
+++ b/OpenAL32/Include/alMain.h
@@ -310,6 +310,7 @@ struct ALCcontext_struct
     ALboolean   InUse;
 
     ALenum      DistanceModel;
+    ALboolean   SourceDistanceModel;
 
     ALfloat     DopplerFactor;
     ALfloat     DopplerVelocity;