From ee237d2a4e43d4f367bdacb09c69f2737fc740b4 Mon Sep 17 00:00:00 2001
From: Simon Sticko <simon@sticko.se>
Date: Tue, 16 Nov 2021 14:56:32 +0100
Subject: [PATCH] Add MappingCartesian::maybe_update_volume_elements()

To remove some duplication in the class.
---
 include/deal.II/fe/mapping_cartesian.h |  7 ++++++
 source/fe/mapping_cartesian.cc         | 34 ++++++++++++++------------
 2 files changed, 25 insertions(+), 16 deletions(-)

diff --git a/include/deal.II/fe/mapping_cartesian.h b/include/deal.II/fe/mapping_cartesian.h
index 71e0aa385b..127d570f25 100644
--- a/include/deal.II/fe/mapping_cartesian.h
+++ b/include/deal.II/fe/mapping_cartesian.h
@@ -376,6 +376,13 @@ private:
       &output_data) const;
 
 
+  /**
+   * Compute the volume elements if the UpdateFlags of the incoming
+   * InternalData object say that they should be updated.
+   */
+  void
+  maybe_update_volume_elements(const InternalData &data) const;
+
   /**
    * Compute the Jacobians if the UpdateFlags of the incoming
    * InternalData object say that they should be updated.
diff --git a/source/fe/mapping_cartesian.cc b/source/fe/mapping_cartesian.cc
index 8963c8465b..2d29cbc65b 100644
--- a/source/fe/mapping_cartesian.cc
+++ b/source/fe/mapping_cartesian.cc
@@ -385,6 +385,22 @@ MappingCartesian<dim, spacedim>::maybe_update_jacobian_derivatives(
 
 
 
+template <int dim, int spacedim>
+void
+MappingCartesian<dim, spacedim>::maybe_update_volume_elements(
+  const InternalData &data) const
+{
+  if (data.update_each & update_volume_elements)
+    {
+      double volume = data.cell_extents[0];
+      for (unsigned int d = 1; d < dim; ++d)
+        volume *= data.cell_extents[d];
+      data.volume_element = volume;
+    }
+}
+
+
+
 template <int dim, int spacedim>
 void
 MappingCartesian<dim, spacedim>::maybe_update_jacobians(
@@ -556,14 +572,7 @@ MappingCartesian<dim, spacedim>::fill_fe_face_values(
     for (unsigned int i = 0; i < output_data.boundary_forms.size(); ++i)
       output_data.boundary_forms[i] = J * output_data.normal_vectors[i];
 
-  if (data.update_each & update_volume_elements)
-    {
-      J = data.cell_extents[0];
-      for (unsigned int d = 1; d < dim; ++d)
-        J *= data.cell_extents[d];
-      data.volume_element = J;
-    }
-
+  maybe_update_volume_elements(data);
   maybe_update_jacobians(data, CellSimilarity::none, output_data);
   maybe_update_jacobian_derivatives(data, CellSimilarity::none, output_data);
   maybe_update_inverse_jacobians(data, CellSimilarity::none, output_data);
@@ -620,14 +629,7 @@ MappingCartesian<dim, spacedim>::fill_fe_subface_values(
     for (unsigned int i = 0; i < output_data.boundary_forms.size(); ++i)
       output_data.boundary_forms[i] = J * output_data.normal_vectors[i];
 
-  if (data.update_each & update_volume_elements)
-    {
-      J = data.cell_extents[0];
-      for (unsigned int d = 1; d < dim; ++d)
-        J *= data.cell_extents[d];
-      data.volume_element = J;
-    }
-
+  maybe_update_volume_elements(data);
   maybe_update_jacobians(data, CellSimilarity::none, output_data);
   maybe_update_jacobian_derivatives(data, CellSimilarity::none, output_data);
   maybe_update_inverse_jacobians(data, CellSimilarity::none, output_data);
-- 
2.39.5