contrib/brl/bbas/imesh/algo/imesh_intersect.cxx File Reference

#include "imesh_intersect.h"
#include <vcl_limits.h>
#include <vcl_cassert.h>
#include <vgl/vgl_triangle_3d.h>
#include <vgl/vgl_distance.h>

Go to the source code of this file.

Functions
bool	imesh_intersect_triangle (const vgl_point_3d< double > &p, const vgl_vector_3d< double > &d, const vgl_point_3d< double > &a, const vgl_point_3d< double > &b, const vgl_point_3d< double > &c, double &dist, double &u, double &v)
	Intersect the ray from point p with direction d and the triangle defined by a,b,c.
bool	imesh_intersect_triangle (const vgl_point_3d< double > &p, const vgl_vector_3d< double > &d, const vgl_point_3d< double > &a, const vgl_point_3d< double > &b, const vgl_point_3d< double > &c, const vgl_vector_3d< double > &n, double &dist, double &u, double &v)
	Intersect the ray from point p with direction d and the triangle defined by a,b,c.
bool	imesh_intersect_triangle_min_dist (const vgl_point_3d< double > &p, const vgl_vector_3d< double > &d, const vgl_point_3d< double > &a, const vgl_point_3d< double > &b, const vgl_point_3d< double > &c, const vgl_vector_3d< double > &n, double &dist, double &u, double &v)
	Intersect the ray from point p with direction d and the triangle defined by a,b,c.
int	imesh_intersect_min_dist (const vgl_point_3d< double > &p, const vgl_vector_3d< double > &d, const imesh_mesh &mesh, double &dist, double *u, double *v)
	Intersect the ray from point p with direction d and the triangulated mesh.
unsigned char	imesh_triangle_closest_point (const vgl_point_3d< double > &p, const vgl_point_3d< double > &a, const vgl_point_3d< double > &b, const vgl_point_3d< double > &c, const vgl_vector_3d< double > &n, double &dist, double &u, double &v)
	Find the closest point on the triangle a,b,c to point p.
unsigned char	imesh_triangle_closest_point (const vgl_point_3d< double > &p, const vgl_point_3d< double > &a, const vgl_point_3d< double > &b, const vgl_point_3d< double > &c, double &dist, double &u, double &v)
	Find the closest point on the triangle a,b,c to point p.
vgl_point_3d< double >	imesh_triangle_closest_point (const vgl_point_3d< double > &p, const vgl_point_3d< double > &a, const vgl_point_3d< double > &b, const vgl_point_3d< double > &c, double &dist)
	Find the closest point on the triangle a,b,c to point p.
int	imesh_closest_point (const vgl_point_3d< double > &p, const imesh_mesh &mesh, vgl_point_3d< double > &cp, double *u, double *v)
	Find the closest point on the triangulated mesh to point p.
unsigned char	imesh_triangle_intersect (const vgl_point_2d< double > &p, const vgl_vector_2d< double > &d, const vgl_point_2d< double > &a, const vgl_point_2d< double > &b, const vgl_point_2d< double > &c, double &u, double &v)
	Find the closest intersection point from p along d with triangle a,b,c.
unsigned char	imesh_triangle_intersect (double &u, double &v, const double &du, const double &dv, const double &eps)
	Find the closest intersection point in barycentric coordinates along the vector (du,dv) in barycentric coordinates.

---

Detailed Description

Definition in file imesh_intersect.cxx.

---

Function Documentation

int imesh_closest_point	(	const vgl_point_3d< double > &	p,
		const imesh_mesh &	mesh,
		vgl_point_3d< double > &	cp,
		double *	u,
		double *	v
	)

Find the closest point on the triangulated mesh to point p.

Returns:

the face index of the closest triangle (one of them if on an edge or vertex)

Parameters:

cp	is the closest point on the mesh (returned by reference)
u	and
v	(optional) are the barycentric coordinates of the closest point

Definition at line 317 of file imesh_intersect.cxx.

int imesh_intersect_min_dist	(	const vgl_point_3d< double > &	p,
		const vgl_vector_3d< double > &	d,
		const imesh_mesh &	mesh,
		double &	dist,
		double *	u,
		double *	v
	)

Intersect the ray from point p with direction d and the triangulated mesh.

Returns:

the face index of the closest intersecting triangle

Parameters:

dist	is the distance to the triangle (returned by reference)
u	and
v	(optional) are the barycentric coordinates of the intersection

Definition at line 136 of file imesh_intersect.cxx.

bool imesh_intersect_triangle	(	const vgl_point_3d< double > &	p,
		const vgl_vector_3d< double > &	d,
		const vgl_point_3d< double > &	a,
		const vgl_point_3d< double > &	b,
		const vgl_point_3d< double > &	c,
		double &	dist,
		double &	u,
		double &	v
	)

Intersect the ray from point p with direction d and the triangle defined by a,b,c.

Returns:

true if intersection occurs

Parameters:

dist	is the distance to the triangle (returned by reference)
u	and
v	are the barycentric coordinates of the intersection

Definition at line 39 of file imesh_intersect.cxx.

bool imesh_intersect_triangle	(	const vgl_point_3d< double > &	p,
		const vgl_vector_3d< double > &	d,
		const vgl_point_3d< double > &	a,
		const vgl_point_3d< double > &	b,
		const vgl_point_3d< double > &	c,
		const vgl_vector_3d< double > &	n,
		double &	dist,
		double &	u,
		double &	v
	)

Intersect the ray from point p with direction d and the triangle defined by a,b,c.

The un-normalized normal vector (b-a)x(c-a) is precomputed and also passed in

Returns:

true if intersection occurs

Parameters:

dist	is the distance to the triangle (returned by reference)
u	and
v	are the barycentric coordinates of the intersection

Definition at line 57 of file imesh_intersect.cxx.

bool imesh_intersect_triangle_min_dist	(	const vgl_point_3d< double > &	p,
		const vgl_vector_3d< double > &	d,
		const vgl_point_3d< double > &	a,
		const vgl_point_3d< double > &	b,
		const vgl_point_3d< double > &	c,
		const vgl_vector_3d< double > &	n,
		double &	dist,
		double &	u,
		double &	v
	)

Intersect the ray from point p with direction d and the triangle defined by a,b,c.

The un-normalized normal vector (b-a)x(c-a) is precomputed and also passed in

Returns:

true if intersection occurs and the new dist is less than the old distance (but > 0)

Parameters:

dist	is the distance to the triangle (returned by reference)
u	and
v	are the barycentric coordinates of the intersection

Definition at line 97 of file imesh_intersect.cxx.

unsigned char imesh_triangle_closest_point	(	const vgl_point_3d< double > &	p,
		const vgl_point_3d< double > &	a,
		const vgl_point_3d< double > &	b,
		const vgl_point_3d< double > &	c,
		const vgl_vector_3d< double > &	n,
		double &	dist,
		double &	u,
		double &	v
	)

Find the closest point on the triangle a,b,c to point p.

The un-normalized normal vector (b-a)x(c-a) is precomputed and also passed in

Returns:

a code indicating that the closest point:

• 0 does not exist (should not occur)
• 1 is a
• 2 is b
• 3 is on the edge from a to b
• 4 is c
• 5 is on the edge from a to c
• 6 is on the edge from b to c
• 7 is on the face of the triangle

Parameters:

dist	is the distance to the triangle (returned by reference)
u	and
v	are the barycentric coordinates of the closest point

Definition at line 185 of file imesh_intersect.cxx.

unsigned char imesh_triangle_closest_point	(	const vgl_point_3d< double > &	p,
		const vgl_point_3d< double > &	a,
		const vgl_point_3d< double > &	b,
		const vgl_point_3d< double > &	c,
		double &	dist,
		double &	u,
		double &	v
	)

Find the closest point on the triangle a,b,c to point p.

Returns:

a code same as other version of this function

Parameters:

dist	is the distance to the triangle (returned by reference)
u	and
v	are the barycentric coordinates of the closest point

Definition at line 284 of file imesh_intersect.cxx.

vgl_point_3d<double> imesh_triangle_closest_point	(	const vgl_point_3d< double > &	p,
		const vgl_point_3d< double > &	a,
		const vgl_point_3d< double > &	b,
		const vgl_point_3d< double > &	c,
		double &	dist
	)

Find the closest point on the triangle a,b,c to point p.

Parameters:

dist	is the distance to the triangle (returned by reference)

Definition at line 299 of file imesh_intersect.cxx.

unsigned char imesh_triangle_intersect	(	const vgl_point_2d< double > &	p,
		const vgl_vector_2d< double > &	d,
		const vgl_point_2d< double > &	a,
		const vgl_point_2d< double > &	b,
		const vgl_point_2d< double > &	c,
		double &	u,
		double &	v
	)

Find the closest intersection point from p along d with triangle a,b,c.

Returns:

a code indicating that the intersection point:

• 0 does not exist
• 1 is a
• 2 is b
• 3 is on the edge from a to b
• 4 is c
• 5 is on the edge from a to c
• 6 is on the edge from b to c
• 7 could not be computed (error)

Parameters:

u	and
v	are the barycentric coordinates of the intersection

Definition at line 362 of file imesh_intersect.cxx.

unsigned char imesh_triangle_intersect	(	double &	u,
		double &	v,
		const double &	du,
		const double &	dv,
		const double &	eps
	)

Find the closest intersection point in barycentric coordinates along the vector (du,dv) in barycentric coordinates.

Find the closest intersection point along the vector (du,dv).

Returns:

a code indicating that the intersection point:

• 0 does not exist
• 1 is at corner (0,0)
• 2 is at corner (1,0)
• 3 is on the edge v=0
• 4 is at corner (0,1)
• 5 is on the edge from u=0
• 6 is on the edge from u+v=1
• 7 could not be computed (error)

Parameters:

u	and
v	are updated to the coordinates of the intersection

Definition at line 396 of file imesh_intersect.cxx.