Physsim::Triangle Class Reference

Defines a triangle for use in collision detection and visualization geometries. More...

#include <Triangle.h>

Inheritance diagram for Physsim::Triangle:

List of all members.

Public Member Functions
	Triangle (Vector3ConstPtr a, Vector3ConstPtr b, Vector3ConstPtr c)
	Constructs the triangle.
	Triangle (const Vector3 &a, const Vector3 &b, const Vector3 &c)
	Constructs the triangle, making copies of the vertices.
	~Triangle ()
	Destroys the triangle.
	Triangle (const Triangle &t)
void	operator= (const Triangle &t)
	Overloads the assignment operator.
Vector3ConstPtr	get_vertex (unsigned i) const
	Gets the specified vertex of the triangle.
const Vector3 &	normal () const
bool	on_vertex (const Vector3 &x) const
	Determines whether a point is on a vertex of the triangle.
bool	on_edge (const Vector3 &x) const
	Determines whether a point is on an edge of the triangle.
bool	inside (const Vector3 &x) const
	Determines whether a point is inside this triangle.
bool	strictly_inside (const Vector3 &x) const
	Determines whether a point is strictly inside this triangle.
void	to_VRML (std::ostream &o, bool wireframe) const
	Sends the triangle to the specified stream using VRML.
void	set_a (Vector3ConstPtr a)
	Sets the vertex 'a'.
void	set_b (Vector3ConstPtr b)
	Sets the vertex 'b'.
void	set_c (Vector3ConstPtr c)
	Sets the vertex 'c'.
void	set_a (const Vector3 &a)
void	set_b (const Vector3 &b)
void	set_c (const Vector3 &c)
Real	get_area () const
void	force_normal_update ()
	Calculates the outward facing normal for this triangle (triangle is assumed to be oriented counter-clockwise).
Real	calc_distance (const Vector3 &point, Vector3 &closest_point) const
	Determines the distance between this triangle and a given point.
Real	get_d () const
	Gets the value 'd' in the equation n[X]*x + n[Y]*y + n[Z]*z - d, where n is the normal of the triangle, and [x y z] is a point on the triangle.
Vector3ConstPtr	a () const
	The first vertex of the triangle.
Vector3ConstPtr	b () const
	The second vertex of the triangle.
Vector3ConstPtr	c () const
	The third vertex of the triangle.
Static Public Member Functions
static bool	intersects (const Triangle &t1, const Triangle &t2)
	Triangle intersection test, adapted from PQP.
static Triangle	transform (const Triangle &t, const Matrix4 &m)
	Transforms the given triangle using the specified transformation matrix.

---

Detailed Description

Defines a triangle for use in collision detection and visualization geometries.

---

Member Function Documentation

bool Triangle::intersects	(	const Triangle &	t1,
		const Triangle &	t2
	)			[static]

Triangle intersection test, adapted from PQP.

Note:

this method does not work correctly at the moment; see results of test_tri_isect

Vector3ConstPtr Triangle::get_vertex

(

unsigned

i

)

const

Gets the specified vertex of the triangle.

Parameters:

i

a zero-index in the range [0,2]

void Triangle::force_normal_update

(

)

Calculates the outward facing normal for this triangle (triangle is assumed to be oriented counter-clockwise).

The user will only need to call this method directly if the triangle's vertices are modified outside of the Triangle class.

Note:

this method computes the 'd' value (the value 'd' in the equation x*n[X] + y*n[Y] + z*n[Z] - d = 0, where [x,y,z] is a point on the plane containing the triangle and n is the triangle's normal) as well.

Real Triangle::calc_distance	(	const Vector3 &	point,
		Vector3 &	closest_point
	)			const

Determines the distance between this triangle and a given point.

Parameters:

	point	the query point
	closest_point	the closest point on the triangle is returned here

Returns:

the Euclidean distance between this triangle and the point

Note:

I took this code almost verbatim from Dave Eberly; need to ask his permission to use it!

---

The documentation for this class was generated from the following files:

• /home/drumwrig/Physsim/include/Physsim/Triangle.h
• /home/drumwrig/Physsim/src/Triangle.cpp

---