measure.cpp File Reference

#include <math.h>
#include "measure.hpp"

Go to the source code of this file.

Classes
class	CartVect
Functions
CartVect	operator+ (const CartVect &v1, const CartVect &v2)
CartVect	operator- (const CartVect &v1, const CartVect &v2)
double	operator% (const CartVect &v1, const CartVect &v2)
CartVect	operator* (const CartVect &v1, const CartVect &v2)
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)

---

Function Documentation

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

Definition at line 145 of file measure.cpp.

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

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

Definition at line 153 of file measure.cpp.

{
  const CartVect* coords = reinterpret_cast<const CartVect*>(vertex_coordinates);
  switch( type )
  {
    case moab::MBEDGE:
      return (coords[0] - coords[1]).len();
    case moab::MBTRI:
      return 0.5 * ((coords[1] - coords[0]) * (coords[2] - coords[0])).len();
    case moab::MBQUAD:
      num_vertices = 4;
    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])).len();
      }
      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;
  }
}

double operator%	(	const CartVect &	v1,
		const CartVect &	v2
	)		[inline]

Definition at line 110 of file measure.cpp.

{
  return v1.x() * v2.x() + v1.y() * v2.y() + v1.z() * v2.z();
}

CartVect operator*	(	const CartVect &	v1,
		const CartVect &	v2
	)		[inline]

Definition at line 115 of file measure.cpp.

{
  return CartVect( v1.y() * v2.z() - v1.z() * v2.y(),
                   v1.z() * v2.x() - v1.x() * v2.z(),
                   v1.x() * v2.y() - v1.y() * v2.x() );
}

CartVect operator+	(	const CartVect &	v1,
		const CartVect &	v2
	)		[inline]

Definition at line 96 of file measure.cpp.

{
  CartVect rval(v1);
  rval += v2;
  return rval;
}

CartVect operator-	(	const CartVect &	v1,
		const CartVect &	v2
	)		[inline]

Definition at line 103 of file measure.cpp.

{
  CartVect rval(v1);
  rval -= v2;
  return rval;
}

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

Definition at line 137 of file measure.cpp.

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