diff --git a/panda/src/putil/bitMask.I b/panda/src/putil/bitMask.I
index 9c7de08321..125bf564d1 100644
--- a/panda/src/putil/bitMask.I
+++ b/panda/src/putil/bitMask.I
@@ -821,6 +821,18 @@ operator >>= (int shift) {
   _word >>= shift;
 }
 
+////////////////////////////////////////////////////////////////////
+//     Function: BitMask::operator WType
+//       Access: Published
+//  Description: Used to cast this BitMask back into the
+//               underlying integer type.
+////////////////////////////////////////////////////////////////////
+template<class WType, int nbits>
+INLINE BitMask<WType, nbits>::
+operator WType () const {
+  return _word;
+}
+
 ////////////////////////////////////////////////////////////////////
 //     Function: BitMask::get_key
 //       Access: Published
diff --git a/panda/src/putil/bitMask.h b/panda/src/putil/bitMask.h
index fdc3b58fc1..318ced9665 100644
--- a/panda/src/putil/bitMask.h
+++ b/panda/src/putil/bitMask.h
@@ -118,6 +118,8 @@ PUBLISHED:
   INLINE void operator <<= (int shift);
   INLINE void operator >>= (int shift);
 
+  INLINE operator WType () const;
+
   INLINE void flood_down_in_place();
   INLINE void flood_up_in_place();
   INLINE BitMask<WType, nbits> flood_bits_down() const;