From: Wolfgang Bangerth <bangerth@math.tamu.edu>
Date: Thu, 30 Jul 2009 13:21:24 +0000 (+0000)
Subject: Add functions project_to_surface to the Boundary description.
X-Git-Tag: v8.0.0~7426
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=039502447aab7897a568ba2129dddee73790bc1c;p=dealii.git

Add functions project_to_surface to the Boundary description.

git-svn-id: https://svn.dealii.org/trunk@19139 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/deal.II/include/grid/tria_boundary.h b/deal.II/deal.II/include/grid/tria_boundary.h
index 7fedc661a9..d0b5f65eca 100644
--- a/deal.II/deal.II/include/grid/tria_boundary.h
+++ b/deal.II/deal.II/include/grid/tria_boundary.h
@@ -2,7 +2,7 @@
 //    $Id$
 //    Version: $Name$
 //
-//    Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by the deal.II authors
+//    Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 by the deal.II authors
 //
 //    This file is subject to QPL and may not be  distributed
 //    without copyright and license information. Please refer
@@ -73,7 +73,7 @@ template <int dim, int space_dim> class Triangulation;
  *   around a given center point.
  *
  * @ingroup boundary
- *   @author Wolfgang Bangerth, 1999, 2001, Ralf Hartmann, 2001, 2008
+ * @author Wolfgang Bangerth, 1999, 2001, 2009, Ralf Hartmann, 2001, 2008
  */
 template <int dim, int spacedim=dim>
 class Boundary : public Subscriptor
@@ -280,6 +280,46 @@ class Boundary : public Subscriptor
     virtual void
     get_normals_at_vertices (const typename Triangulation<dim,spacedim>::face_iterator &face,
 			     FaceVertexNormals &face_vertex_normals) const;
+
+				     /**
+				      * Given a candidate point and a
+				      * line segment characterized by
+				      * the iterator, return a point
+				      * that lies on the surface
+				      * described by this object. This
+				      * function is used in some mesh
+				      * smoothing algorithms that try
+				      * to move around points in order
+				      * to improve the mesh quality
+				      * but need to ensure that points
+				      * that were on the boundary
+				      * remain on the boundary.
+				      *
+				      * Derived classes do not need to
+				      * implement this function unless
+				      * mesh smoothing algorithms are
+				      * used with a particular
+				      * boundary object. The default
+				      * implementation of this
+				      * function throws an exception
+				      * of type ExcPureFunctionCalled.
+				      */
+    virtual
+    Point<spacedim>
+    project_to_surface (const typename Triangulation<dim,spacedim>::line_iterator &line,
+			const Point<spacedim> &candidate) const;
+
+				     /**
+				      * Same function as above but for
+				      * a point that is to be
+				      * projected onto the area
+				      * characterized by the given
+				      * quad.
+				      */
+    virtual
+    Point<spacedim>
+    project_to_surface (const typename Triangulation<dim,spacedim>::quad_iterator &quad,
+			const Point<spacedim> &candidate) const;
 };
 
 
@@ -387,6 +427,50 @@ class StraightBoundary : public Boundary<dim,spacedim>
     virtual void
     get_normals_at_vertices (const typename Triangulation<dim,spacedim>::face_iterator &face,
 			     typename Boundary<dim,spacedim>::FaceVertexNormals &face_vertex_normals) const;
+
+				     /**
+				      * Given a candidate point and a
+				      * line segment characterized by
+				      * the iterator, return a point
+				      * that lies on the surface
+				      * described by this object. This
+				      * function is used in some mesh
+				      * smoothing algorithms that try
+				      * to move around points in order
+				      * to improve the mesh quality
+				      * but need to ensure that points
+				      * that were on the boundary
+				      * remain on the boundary.
+				      *
+				      * The point returned is the
+				      * projection of the candidate
+				      * point onto the line through
+				      * the two vertices of the given
+				      * line iterator.
+				      */
+    virtual
+    Point<spacedim>
+    project_to_surface (const typename Triangulation<dim,spacedim>::line_iterator &line,
+			const Point<spacedim> &candidate) const;
+
+				     /**
+				      * Same function as above but for
+				      * a point that is to be
+				      * projected onto the area
+				      * characterized by the given
+				      * quad.
+				      *
+				      * The point returned is the
+				      * projection of the candidate
+				      * point onto the bilinear
+				      * surface spanned by the four
+				      * vertices of the given quad
+				      * iterator.
+				      */
+    virtual
+    Point<spacedim>
+    project_to_surface (const typename Triangulation<dim,spacedim>::quad_iterator &quad,
+			const Point<spacedim> &candidate) const;
 };
 
 
diff --git a/deal.II/deal.II/source/grid/tria_boundary.cc b/deal.II/deal.II/source/grid/tria_boundary.cc
index 0254258eff..c89556a76e 100644
--- a/deal.II/deal.II/source/grid/tria_boundary.cc
+++ b/deal.II/deal.II/source/grid/tria_boundary.cc
@@ -2,7 +2,7 @@
 //    $Id$
 //    Version: $Name$
 //
-//    Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2008 by the deal.II authors
+//    Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2008, 2009 by the deal.II authors
 //
 //    This file is subject to QPL and may not be  distributed
 //    without copyright and license information. Please refer
@@ -163,6 +163,30 @@ get_normals_at_vertices (const typename Triangulation<dim, spacedim>::face_itera
 
 
 
+template <int dim, int spacedim>
+Point<spacedim>
+Boundary<dim, spacedim>::
+project_to_surface (const typename Triangulation<dim, spacedim>::line_iterator &,
+		    const Point<spacedim>                                &) const
+{
+  Assert (false, ExcPureFunctionCalled());
+  return Point<spacedim>();
+}
+
+
+
+template <int dim, int spacedim>
+Point<spacedim>
+Boundary<dim, spacedim>::
+project_to_surface (const typename Triangulation<dim, spacedim>::quad_iterator &,
+		    const Point<spacedim>                                &) const
+{
+  Assert (false, ExcPureFunctionCalled());
+  return Point<spacedim>();
+}
+
+
+
 /* -------------------------- StraightBoundary --------------------- */
 
 
@@ -461,6 +485,30 @@ get_normals_at_vertices (const Triangulation<3>::face_iterator &face,
 #endif
 
 
+template <int dim, int spacedim>
+Point<spacedim>
+StraightBoundary<dim, spacedim>::
+project_to_surface (const typename Triangulation<dim, spacedim>::line_iterator &,
+		    const Point<spacedim>                                &) const
+{
+  Assert (false, ExcPureFunctionCalled());
+  return Point<spacedim>();
+}
+
+
+
+template <int dim, int spacedim>
+Point<spacedim>
+StraightBoundary<dim, spacedim>::
+project_to_surface (const typename Triangulation<dim, spacedim>::quad_iterator &,
+		    const Point<spacedim>                                &) const
+{
+  Assert (false, ExcPureFunctionCalled());
+  return Point<spacedim>();
+}
+
+
+
 // explicit instantiations
 template class Boundary<deal_II_dimension>;
 template class StraightBoundary<deal_II_dimension>;