Commit 0941d75e authored by Jakub Klinkovský's avatar Jakub Klinkovský
Browse files

Simplified and generalized the getEntityCenter function

parent 56ae3522

src/TNL/Meshes/Geometry/getEntityCenter.h

+22 −36
Original line number Diff line number Diff line
@@ -14,10 +14,6 @@ 
#include <TNL/Meshes/GridEntity.h>

#include <TNL/Meshes/Mesh.h>

#include <TNL/Meshes/MeshEntity.h>

#include <TNL/Meshes/Topologies/Vertex.h>

#include <TNL/Meshes/Topologies/Edge.h>

#include <TNL/Meshes/Topologies/Triangle.h>

#include <TNL/Meshes/Topologies/Tetrahedron.h>



namespace TNL {

namespace Meshes {
@@ -40,40 +36,30 @@ getEntityCenter( const Mesh< MeshConfig, Device > & mesh, 
   return entity.getPoint();

}



template< typename MeshConfig, typename Device >

/*

 * Get an arithmetic mean of the entity's subvertices.

 *

 * For an simplex entity this corresponds to the centroid of the entity, but

 * note that other shapes such as general polygons have different formulas for

 * the centroid: https://en.wikipedia.org/wiki/Centroid#Centroid_of_a_polygon

 */

template< typename MeshConfig, typename Device, typename EntityTopology >

__cuda_callable__

typename MeshTraits< MeshConfig >::PointType

getEntityCenter( const Mesh< MeshConfig, Device > & mesh,

                 const MeshEntity< MeshConfig, Device, Topologies::Edge > & entity )

                 const MeshEntity< MeshConfig, Device, EntityTopology > & entity )

{

    const auto& v0 = mesh.template getEntity< 0 >( entity.template getSubentityIndex< 0 >( 0 ) );

    const auto& v1 = mesh.template getEntity< 0 >( entity.template getSubentityIndex< 0 >( 1 ) );

    return 0.5 * ( v0.getPoint() + v1.getPoint() );

}



template< typename MeshConfig, typename Device >

__cuda_callable__

typename MeshTraits< MeshConfig >::PointType

getEntityCenter( const Mesh< MeshConfig, Device > & mesh,

                 const MeshEntity< MeshConfig, Device, Topologies::Triangle > & entity )

   using EntityType = MeshEntity< MeshConfig, Device, EntityTopology >;

   constexpr typename MeshConfig::LocalIndexType subvertices = EntityType::template getSubentitiesCount< 0 >();

   typename MeshTraits< MeshConfig >::PointType c{ 0.0 };

   for( typename MeshConfig::LocalIndexType i = 0;

        i < subvertices;

        i++ )

   {

    const auto& v0 = mesh.template getEntity< 0 >( entity.template getSubentityIndex< 0 >( 0 ) );

    const auto& v1 = mesh.template getEntity< 0 >( entity.template getSubentityIndex< 0 >( 1 ) );

    const auto& v2 = mesh.template getEntity< 0 >( entity.template getSubentityIndex< 0 >( 2 ) );

    return ( 1.0 / 3.0 ) * ( v0.getPoint() + v1.getPoint() + v2.getPoint() );

      const auto& v = mesh.template getEntity< 0 >( entity.template getSubentityIndex< 0 >( i ) );

      c += v.getPoint();

   }



template< typename MeshConfig, typename Device >

__cuda_callable__

typename MeshTraits< MeshConfig >::PointType

getEntityCenter( const Mesh< MeshConfig, Device > & mesh,

                 const MeshEntity< MeshConfig, Device, Topologies::Tetrahedron > & entity )

{

    const auto& v0 = mesh.template getEntity< 0 >( entity.template getSubentityIndex< 0 >( 0 ) );

    const auto& v1 = mesh.template getEntity< 0 >( entity.template getSubentityIndex< 0 >( 1 ) );

    const auto& v2 = mesh.template getEntity< 0 >( entity.template getSubentityIndex< 0 >( 2 ) );

    const auto& v3 = mesh.template getEntity< 0 >( entity.template getSubentityIndex< 0 >( 3 ) );

    return 0.25 * ( v0.getPoint() + v1.getPoint() + v2.getPoint() + v3.getPoint() );

   return ( 1.0 / subvertices ) * c;

}



} // namespace Meshes