diff --git a/utils/field/vector.py b/utils/field/vector.py
index e348435e09..3da17856dd 100644
--- a/utils/field/vector.py
+++ b/utils/field/vector.py
@@ -1044,7 +1044,7 @@ def _evaluate(self, vertices):
         if self.only_2D:
             return self.surface.evaluate_array(us, vs)
 
-        spline_normals, surf_vertices = self.surface.normal_array_with_source_vertices(us, vs)
+        spline_normals, surf_vertices = self.surface.normal_vertices_array(us, vs)
         zs = vertices[:,self.orient_axis].flatten()
         zs = zs[np.newaxis].T
         v1 = zs * spline_normals
diff --git a/utils/surface/algorithms.py b/utils/surface/algorithms.py
index 7404cf3a5b..10941e8bc3 100644
--- a/utils/surface/algorithms.py
+++ b/utils/surface/algorithms.py
@@ -159,11 +159,7 @@ def normal(self, u, v):
 #         normals = [self._normal(u, v) for u,v in zip(us, vs)]
 #         return np.array(normals)
 
-    def normal_array(self, us, vs):
-        result_normals, *_ = self.normal_array_with_source_vertices(us, vs)
-        return result_normals
-
-    def normal_array_with_source_vertices(self, us, vs):
+    def normal_vertices_array(self, us, vs):
         h = 0.001
         _points         = np.empty( (0, 3), dtype=np.float64)
         _points_u_h     = np.empty( (0, 3), dtype=np.float64)
@@ -316,7 +312,7 @@ def normal(self, u, v):
         normal = normal / n
         return normal
 
-    def normal_array(self, us, vs):
+    def normal_vertices_array(self, us, vs):
         surf_vertices = self.evaluate_array(us, vs)
         u_plus = self.evaluate_array(us + self.normal_delta, vs)
         v_plus = self.evaluate_array(us, vs + self.normal_delta)
@@ -329,7 +325,7 @@ def normal_array(self, us, vs):
         #if norm != 0:
         normal = normal / norm
         #self.info("Normals: %s", normal)
-        return normal
+        return normal, surf_vertices
 
 class SvRevolutionSurface(SvSurface):
     __description__ = "Revolution"
diff --git a/utils/surface/core.py b/utils/surface/core.py
index e93c0a02e2..800fded7c8 100644
--- a/utils/surface/core.py
+++ b/utils/surface/core.py
@@ -38,6 +38,10 @@ def normal(self, u, v):
         return normal
 
     def normal_array(self, us, vs):
+        normal, *_ = self.normal_vertices_array(us, vs)
+        return normal
+
+    def normal_vertices_array(self, us, vs):
         surf_vertices = self.evaluate_array(us, vs)
         u_plus = self.evaluate_array(us + self.normal_delta, vs)
         v_plus = self.evaluate_array(us, vs + self.normal_delta)
@@ -50,7 +54,7 @@ def normal_array(self, us, vs):
         #if norm != 0:
         normal = normal / norm
         #self.info("Normals: %s", normal)
-        return normal
+        return normal, surf_vertices
 
     def derivatives_data_array(self, us, vs):
         if hasattr(self, 'normal_delta'):
@@ -403,7 +407,7 @@ def evaluate_array(self, us, vs):
     def normal(self, u, v):
         return self.normal_array(np.array([u]), np.array([v]))[0]
 
-    def normal_array(self, us, vs):
+    def normal_vertices_array(self, us, vs):
         surf_vertices = self.evaluate_array(us, vs)
         u_plus = self.evaluate_array(us + self.normal_delta, vs)
         v_plus = self.evaluate_array(us, vs + self.normal_delta)
@@ -416,5 +420,5 @@ def normal_array(self, us, vs):
         #if norm != 0:
         normal = normal / norm
         #self.info("Normals: %s", normal)
-        return normal
+        return normal, surf_vertices
 
diff --git a/utils/surface/rbf.py b/utils/surface/rbf.py
index 969e09d4c4..b6d894cc8b 100644
--- a/utils/surface/rbf.py
+++ b/utils/surface/rbf.py
@@ -69,7 +69,7 @@ def evaluate_array(self, us, vs):
     def normal(self, u, v):
         return self.normal_array(np.array([u]), np.array([v]))[0]
 
-    def normal_array(self, us, vs):
+    def normal_vertices_array(self, us, vs):
         surf_vertices = self.evaluate_array(us, vs)
         u_plus = self.evaluate_array(us + self.normal_delta, vs)
         v_plus = self.evaluate_array(us, vs + self.normal_delta)
@@ -82,5 +82,5 @@ def normal_array(self, us, vs):
         #if norm != 0:
         normal = normal / norm
         #self.info("Normals: %s", normal)
-        return normal
+        return normal, surf_vertices