BF: Transform->affine changes. Make sure we don't generate an empty affine for

coefficient fields

fsl/data/image.py

@@ -337,9 +337,9 @@ class Nifti(notifier.Notifier, meta.Meta):
             # get the shape/size of the coefficient
             # field about right
             knotpix       =  header.get_zooms()[:3]
-            refpix        = (header.get('intent_p1', 1),
-                             header.get('intent_p2', 1),
-                             header.get('intent_p3', 1))
+            refpix        = (header.get('intent_p1', 1) or 1,
+                             header.get('intent_p2', 1) or 1,
+                             header.get('intent_p3', 1) or 1)
             voxToWorldMat = affine.concat(
                 affine.scaleOffsetXform(refpix,  0),
                 affine.scaleOffsetXform(knotpix, 0))

fsl/data/mghimage.py

@@ -69,7 +69,7 @@ class MGHImage(fslimage.Image):
 
         self.__voxToSurfMat   = vox2surf
         self.__surfToVoxMat   = affine.invert(vox2surf)
-        self.__surfToWorldMat = affine.concat(affine, self.__surfToVoxMat)
+        self.__surfToWorldMat = affine.concat(xform, self.__surfToVoxMat)
         self.__worldToSurfMat = affine.invert(self.__surfToWorldMat)