vector_constraint Class Reference

List of all members.

Public Members
		vector_constraint ( const double u, const double x1, const double y1 )
		The only constructor for an `angle_constraint.` More...
	virtual	~vector_constraint (void)
	virtual void	energy ( const double tol, const vector< vector2 > &p, double &e, vector< vector2 > &dedp ) const
		Calculate a dimensionless measure of the potential energy (e) of the `constraint.` More...
	double	x
		The x coordinate of the expected position of `points()[1],` relative to `points()[0].`
	double	y
		The y coordinate of the expected position of `points()[1],` relative to `points()[0].`
Friends
	void	assoc ( vector_constraint &c, vector2 &p0, vector2 &p1 )
		Associates a `vector_constraint` with the 2 points it constrains. More...
	void	unassoc ( vector_constraint &c )
		Disassociates a `vector_constraint` from the points it constrains. More...

Detailed Description

Constrain the relative position of two points.

Definition at line 39 of file vector_constraint.h.

Member Function Documentation

vector_constraint::vector_constraint (const double u, const double x1, const double y1)

The only constructor for an angle_constraint.

Parameters:

u	the degree of uncertainty of the constriant.
x1	the x coordinate of the relative position of the two points
y1	the y coordinate of the relative position of the two points

Postconditions:

 assert( this->uncertainty() == u );
 assert( this->x == x1 );
 assert( this->y == y1 );
 assert( this->points().size() == 2 );

Definition at line 36 of file vector_constraint.cpp.

vector_constraint::~vector_constraint (void) [virtual]

Definition at line 59 of file vector_constraint.cpp.

void vector_constraint::energy (const double tol, const vector<vector2>& p, double & e, vector<vector2>& dedp) const [virtual]

Calculate a dimensionless measure of the potential energy (e) of the constraint.

This is equivalent to a measure of how poorly the constraint is satisfied. If *(this->points()[i]) had position p[i], it calculates the energy (e) and the rates of change of that energy (dedp) with respect to the point positions. Larger values indicate the constraint is less well satisfied. 0 is the minimum possible energy, and energy <= 1 indicates that the constraint is satisifed to within the uncertainty of the constraint.

Parameters:

tol	is a dimensionless calculation tolerance.
p	are the point positions.

Return values:

e	the energy.
dedp	is the rate of change of energy with position.

Preconditions:

 assert( p.size() == 2 );
 assert( 0 < tol && tol < 1 );

Postconditions:

 assert( dedp.size() == 2 );

Reimplemented from constraint.

Definition at line 66 of file vector_constraint.cpp.

Friends And Related Function Documentation

void assoc (vector_constraint & c, vector2 & p0, vector2 & p1) [friend]

Associates a vector_constraint with the 2 points it constrains.

Preconditions:

 assert( !c.points()[0] );

Postconditions:

 assert( c.points()[0] == &p0 );
 assert( c.points()[1] == &p1 );

Definition at line 184 of file vector_constraint.h.

void unassoc (vector_constraint & c) [friend]

Disassociates a vector_constraint from the points it constrains.

Postconditions:

 assert( !c.points()[0] );
 assert( !c.points()[1] );

Definition at line 203 of file vector_constraint.h.

Member Data Documentation

double vector_constraint::x

The x coordinate of the expected position of points()[1], relative to points()[0].

Definition at line 110 of file vector_constraint.h.

double vector_constraint::y

The y coordinate of the expected position of points()[1], relative to points()[0].

Definition at line 116 of file vector_constraint.h.

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

Generated at Sun Jul 14 20:38:22 2002 for Mapper by

vector_constraint Class Reference

Public Members

Friends

Detailed Description

Member Function Documentation

Friends And Related Function Documentation

Member Data Documentation