From: wolf <wolf@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Thu, 1 May 2003 23:48:00 +0000 (+0000)
Subject: GeometryInfo::child_to_cell_coordinates
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cc2d745e3595b1b11d1e683932fec7af8b57a0cf;p=dealii-svn.git

GeometryInfo::child_to_cell_coordinates


git-svn-id: https://svn.dealii.org/trunk@7541 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/deal.II/include/grid/geometry_info.h b/deal.II/deal.II/include/grid/geometry_info.h
index 98074da542..890c45cf2f 100644
--- a/deal.II/deal.II/include/grid/geometry_info.h
+++ b/deal.II/deal.II/include/grid/geometry_info.h
@@ -355,6 +355,17 @@ struct GeometryInfo<1>
     static Point<1> cell_to_child_coordinates (const Point<1>    &p,
 					       const unsigned int child_index);
 
+				     /**
+				      * The reverse function to the
+				      * one above: take a point in the
+				      * coordinate system of the
+				      * child, and transform it to the
+				      * coordinate system of the
+				      * mother cell.
+				      */
+    static Point<1> child_to_cell_coordinates (const Point<1>    &p,
+					       const unsigned int child_index);
+
 				     /**
 				      * Return true if the given point
 				      * is inside the unit cell of the
@@ -604,6 +615,17 @@ struct GeometryInfo<2>
     static Point<2> cell_to_child_coordinates (const Point<2>    &p,
 					       const unsigned int child_index);
 
+				     /**
+				      * The reverse function to the
+				      * one above: take a point in the
+				      * coordinate system of the
+				      * child, and transform it to the
+				      * coordinate system of the
+				      * mother cell.
+				      */
+    static Point<2> child_to_cell_coordinates (const Point<2>    &p,
+					       const unsigned int child_index);
+
 				     /**
 				      * Return true if the given point
 				      * is inside the unit cell of the
@@ -851,6 +873,17 @@ struct GeometryInfo<3>
     static Point<3> cell_to_child_coordinates (const Point<3>    &p,
 					       const unsigned int child_index);
 
+				     /**
+				      * The reverse function to the
+				      * one above: take a point in the
+				      * coordinate system of the
+				      * child, and transform it to the
+				      * coordinate system of the
+				      * mother cell.
+				      */
+    static Point<3> child_to_cell_coordinates (const Point<3>    &p,
+					       const unsigned int child_index);
+
 				     /**
 				      * Return true if the given point
 				      * is inside the unit cell of the
@@ -1152,6 +1185,55 @@ GeometryInfo<3>::cell_to_child_coordinates (const Point<3>    &p,
 
 
 
+inline
+Point<1>
+GeometryInfo<1>::child_to_cell_coordinates (const Point<1>    &p,
+					    const unsigned int child_index)
+{
+  Assert (child_index < GeometryInfo<dim>::children_per_cell,
+	  ExcIndexRange (child_index, 0, GeometryInfo<dim>::children_per_cell));
+  const double x = p[0]/2 + (child_index == 1 ? .5 : 0.);
+  return Point<dim>(x);
+}
+
+
+
+inline
+Point<2>
+GeometryInfo<2>::child_to_cell_coordinates (const Point<2>    &p,
+					    const unsigned int child_index)
+{
+  Assert (child_index < GeometryInfo<dim>::children_per_cell,
+	  ExcIndexRange (child_index, 0, GeometryInfo<dim>::children_per_cell));
+
+  const double x = p[0]/2 + ((child_index == 1) || (child_index == 2) ? .5 : 0.);
+  const double y = p[1]/2 + ((child_index == 2) || (child_index == 3) ? .5 : 0.);
+    
+  return Point<dim>(x,y);
+}
+
+
+
+inline
+Point<3>
+GeometryInfo<3>::child_to_cell_coordinates (const Point<3>    &p,
+					    const unsigned int child_index)
+{
+  Assert (child_index < GeometryInfo<dim>::children_per_cell,
+	  ExcIndexRange (child_index, 0, GeometryInfo<dim>::children_per_cell));
+
+  const double x = p[0]/2 + ((child_index == 1) || (child_index == 2) ||
+			     (child_index == 5) || (child_index == 6)    ? .5 : 0.);
+  const double y = p[1]/2 + ((child_index == 4) || (child_index == 5) ||
+			     (child_index == 6) || (child_index == 7)    ? .5 : 0.);
+  const double z = p[2]/2 + ((child_index == 2) || (child_index == 3) ||
+			     (child_index == 6) || (child_index == 7)    ? .5 : 0.);
+    
+  return Point<dim>(x,y,z);
+}
+
+
+
 inline
 bool
 GeometryInfo<1>::is_inside_unit_cell (const Point<1> &p)
diff --git a/deal.II/doc/news/2002/c-3-4.html b/deal.II/doc/news/2002/c-3-4.html
index eeb178e667..b9e79035dd 100644
--- a/deal.II/doc/news/2002/c-3-4.html
+++ b/deal.II/doc/news/2002/c-3-4.html
@@ -763,7 +763,9 @@ contributor's names are abbreviated by WB (Wolfgang Bangerth), GK
        in the unit cell, returns which child cell it is on; <code
        class="member">cell_to_child_coordinates</code> that transforms
        coordinates between the unit coordinate systems from the mother
-       to the child cell; and <code
+       to the child cell; <code
+       class="member">child_to_cell_coordinates</code> that does
+       exactly the opposite; and <code
        class="member">is_inside_unit_cell</code> that tells whether a 
        given point is inside the unit cell.
        <br>