diff --git a/src/osg/ShapeDrawable.cpp b/src/osg/ShapeDrawable.cpp
index 852f39095..f05a635eb 100644
--- a/src/osg/ShapeDrawable.cpp
+++ b/src/osg/ShapeDrawable.cpp
@@ -1280,6 +1280,8 @@ void ShapeDrawable::accept(PrimitiveFunctor& pf) const
 
 bool ShapeDrawable::computeBound() const
 {
+    _bbox.init();
+
 
     if (_shape.valid())
     {