3 files changed, 53 insertions, 4 deletions
diff --git a/tksao/frame/fitsimage.C b/tksao/frame/fitsimage.C
index 474326d..2668ef0 100644
--- a/tksao/frame/fitsimage.C
+++ b/tksao/frame/fitsimage.C
@@ -1201,19 +1201,19 @@ void FitsImage::resetWCS()
   else
     initWCS(image_->head());
 
-
   // apply block factor
   if (ast_) {
     Vector block = context_->blockFactor();
-    if (block[0] != 1 && block[1] != 1) {
+    if (block[0] != 1 || block[1] != 1) {
       astClearStatus; // just to make sure
       astBegin; // start memory management
 
       Vector ll(.5,.5);
       Vector ur(1.5,1.5);
       Vector rr = ur*Translate(-.5,-.5)*Scale(block)*Translate(.5,.5);
-      AstWinMap* winmap = astWinMap(2, ll.vv(), rr.vv(), ll.vv(), ur.vv(), "");
-      astRemapFrame(ast_, AST__BASE, winmap);
+      AstWinMap* winmap = wcsWinMap(ast_, ll, ur, rr);
+      if (winmap)
+	astRemapFrame(ast_, AST__BASE, winmap);
 
       astEnd;
     }
diff --git a/tksao/frame/wcsast.C b/tksao/frame/wcsast.C
index d3801f1..5ae4ac7 100644
--- a/tksao/frame/wcsast.C
+++ b/tksao/frame/wcsast.C
@@ -392,3 +392,50 @@ double wcsAxAngle(AstFrameSet* ast, const Vector& vv1, const Vector& vv2)
   return 0;
 }
 
+AstWinMap* wcsWinMap(AstFrameSet* ast, Vector& ll, Vector& ur, Vector& rr)
+{
+  int naxes = astGetI(ast,"Naxes");
+  switch (naxes) {
+  case 1:
+    // error
+    return NULL;
+  case 2:
+    return astWinMap(2, ll.vv(), rr.vv(), ll.vv(), ur.vv(), "");
+  case 3:
+    {
+      double vll[3];
+      vll[0] = ll[0];
+      vll[1] = ll[0];
+      vll[2] = .5;
+      double vur[3];
+      vur[0] = ur[0];
+      vur[1] = ur[0];
+      vur[2] = .5;
+      double vrr[3];
+      vrr[0] = rr[0];
+      vrr[1] = rr[1];
+      vrr[2] = 1.5;
+      return astWinMap(3, vll, vrr, vll, vur, "");
+    }
+  case 4:
+    {
+      double vll[4];
+      vll[0] = ll[0];
+      vll[1] = ll[0];
+      vll[2] = .5;
+      vll[3] = .5;
+      double vur[4];
+      vur[0] = ur[0];
+      vur[1] = ur[0];
+      vur[2] = .5;
+      vur[3] = .5;
+      double vrr[4];
+      vrr[0] = rr[0];
+      vrr[1] = rr[1];
+      vrr[2] = 1.5;
+      vrr[3] = 1.5;
+      return astWinMap(4, vll, vrr, vll, vur, "");
+    }
+    break;
+  }
+}
diff --git a/tksao/frame/wcsast.h b/tksao/frame/wcsast.h
index 6aa42c0..e1c85fe 100644
--- a/tksao/frame/wcsast.h
+++ b/tksao/frame/wcsast.h
@@ -21,3 +21,5 @@ Vector3d wcsTran(AstFrameSet*, const Vector3d&, int);
 double wcsDistance(AstFrameSet*, const Vector&, const Vector&);
 double wcsAngle(AstFrameSet*, const Vector&, const Vector&, const Vector&);
 double wcsAxAngle(AstFrameSet*, const Vector&, const Vector&);
+
+AstWinMap* wcsWinMap(AstFrameSet*, Vector&, Vector&, Vector&);