measure.cpp File Reference

#include "moab/CartVect.hpp"
#include "measure.hpp"

Include dependency graph for measure.cpp:

Go to the source code of this file.

Functions
static double	tet_volume (const CartVect &v0, const CartVect &v1, const CartVect &v2, const CartVect &v3)
double	edge_length (const double *start_vtx_coords, const double *end_vtx_coords)
double	measure (moab::EntityType type, int num_vertices, const double *vertex_coordinates)

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Function Documentation

double edge_length	(	const double *	start_vtx_coords,
		const double *	end_vtx_coords
	)

Definition at line 35 of file measure.cpp.

References moab::CartVect::length().

Referenced by gather_set_stats().

{
    const CartVect* start = reinterpret_cast< const CartVect* >( start_vtx_coords );
    const CartVect* end   = reinterpret_cast< const CartVect* >( end_vtx_coords );
    return ( *start - *end ).length();
}

double measure	(	moab::EntityType	type,
		int	num_vertices,
		const double *	vertex_coordinates
	)

Definition at line 42 of file measure.cpp.

References length(), MBEDGE, MBHEX, MBPOLYGON, MBPRISM, MBPYRAMID, MBQUAD, MBTET, MBTRI, moab::sum(), and tet_volume().

{
    const CartVect* coords = reinterpret_cast< const CartVect* >( vertex_coordinates );
    switch( type )
    {
        case moab::MBEDGE:
            return ( coords[0] - coords[1] ).length();
        case moab::MBTRI:
            return 0.5 * ( ( coords[1] - coords[0] ) * ( coords[2] - coords[0] ) ).length();
        case moab::MBQUAD:
            num_vertices = 4;
            // fall through
        case moab::MBPOLYGON: {
            CartVect mid( 0, 0, 0 );
            for( int i = 0; i < num_vertices; ++i )
                mid += coords[i];
            mid /= num_vertices;

            double sum = 0.0;
            for( int i = 0; i < num_vertices; ++i )
            {
                int j = ( i + 1 ) % num_vertices;
                sum += ( ( mid - coords[i] ) * ( mid - coords[j] ) ).length();
            }
            return 0.5 * sum;
        }
        case moab::MBTET:
            return tet_volume( coords[0], coords[1], coords[2], coords[3] );
        case moab::MBPYRAMID:
            return tet_volume( coords[0], coords[1], coords[2], coords[4] ) +
                   tet_volume( coords[0], coords[2], coords[3], coords[4] );
        case moab::MBPRISM:
            return tet_volume( coords[0], coords[1], coords[2], coords[5] ) +
                   tet_volume( coords[3], coords[5], coords[4], coords[0] ) +
                   tet_volume( coords[1], coords[4], coords[5], coords[0] );
        case moab::MBHEX:
            return tet_volume( coords[0], coords[1], coords[3], coords[4] ) +
                   tet_volume( coords[7], coords[3], coords[6], coords[4] ) +
                   tet_volume( coords[4], coords[5], coords[1], coords[6] ) +
                   tet_volume( coords[1], coords[6], coords[3], coords[4] ) +
                   tet_volume( coords[2], coords[6], coords[3], coords[1] );
        default:
            return 0.0;
    }
}

static double tet_volume	(	const CartVect &	v0,
		const CartVect &	v1,
		const CartVect &	v2,
		const CartVect &	v3
	)		[inline, static]

Definition at line 30 of file measure.cpp.

Referenced by measure().

{
    return 1. / 6. * ( ( ( v1 - v0 ) * ( v2 - v0 ) ) % ( v3 - v0 ) );
}