diff --git a/include/zeus/COBBox.hpp b/include/zeus/COBBox.hpp
index 9beda9f..76392e5 100644
--- a/include/zeus/COBBox.hpp
+++ b/include/zeus/COBBox.hpp
@@ -35,7 +35,7 @@ public:
 
     COBBox(const CTransform& xf, const CVector3f& extents) : transform(xf), extents(extents) {}
 
-    CAABox calculateAABox(const CTransform& transform = CTransform()) const;
+    CAABox calculateAABox(const CTransform& worldXf = CTransform()) const;
 
     static COBBox FromAABox(const CAABox& box, const CTransform& xf)
     {
diff --git a/src/COBBox.cpp b/src/COBBox.cpp
index 7e90dbe..958791d 100644
--- a/src/COBBox.cpp
+++ b/src/COBBox.cpp
@@ -3,15 +3,14 @@
 namespace zeus
 {
 
-CAABox COBBox::calculateAABox(const CTransform& transform) const
+CAABox COBBox::calculateAABox(const CTransform& worldXf) const
 {
     CAABox ret = CAABox::skInvertedBox;
 
-    CTransform trans = transform * transform;
+    CTransform trans = worldXf * transform;
     static const CVector3f basis[8] = {{1.f, 1.f, 1.f},    {1.f, 1.f, -1.f},  {1.f, -1.f, 1.f},  {1.f, -1.f, -1.f},
                                        {-1.f, -1.f, -1.f}, {-1.f, -1.f, 1.f}, {-1.f, 1.f, -1.f}, {-1.f, 1.f, 1.f}};
     CVector3f p = extents * basis[0];
-
     ret.accumulateBounds(trans * p);
     p = extents * basis[1];
     ret.accumulateBounds(trans * p);