2 files changed, 5 insertions, 3 deletions
diff --git a/tksao/frame/fitsimage.C b/tksao/frame/fitsimage.C
index 43ba208..f9fe867 100644
--- a/tksao/frame/fitsimage.C
+++ b/tksao/frame/fitsimage.C
@@ -4146,12 +4146,14 @@ Vector3d FitsImage::wcsTran(AstFrameSet* ast, const Vector3d& in, int forward)
 #endif
 
 #ifndef NEWWCS
-double FitsImage::wcsDistance(AstFrameSet* ast, Vector vv1, Vector vv2)
+double FitsImage::wcsDistance(AstFrameSet* ast, const Vector& vv1,
+			      const Vector& vv2)
 {
   return astDistance(ast, vv1.v, vv2.v);
 }
 #else
-double FitsImage::wcsDistance(AstFrameSet* ast, Vector vv1, Vector vv2)
+double FitsImage::wcsDistance(AstFrameSet* ast, const Vector& vv1,
+			      const Vector& vv2)
 {
   int naxes = astGetI(ast,"Naxes");
   switch (naxes) {
diff --git a/tksao/frame/fitsimage.h b/tksao/frame/fitsimage.h
index acd689e..09de2f3 100644
--- a/tksao/frame/fitsimage.h
+++ b/tksao/frame/fitsimage.h
@@ -408,7 +408,7 @@ class FitsImage {
   int wcsIsASkyFrame(AstFrameSet*);
   Vector wcsTran(AstFrameSet*, const Vector&, int);
   void wcsTran(AstFrameSet*, int, Vector*, int, Vector*);
-  double wcsDistance(AstFrameSet*, Vector, Vector);
+  double wcsDistance(AstFrameSet*, const Vector&, const Vector&);
 #ifdef NEWWCS
   Vector3d wcsTran(AstFrameSet*, const Vector3d&, int);
   double wcsAngle(AstFrameSet*, const Vector&, const Vector&, const Vector&);