Package org.tinfour.common

Class Circumcircle

java.lang.Object

org.tinfour.common.Circumcircle

public class Circumcircle
extends Object

Provides center coordinates and radius for a circumcircle.

Constructor Summary

Constructors

Constructor	Description
Circumcircle()	Standard constructor.

Method Summary

Modifier and Type	Method	Description
void	compute(double x0, double y0, double x1, double y1, double x2, double y2)	Computes the circumcircle for the specified vertices and stores results in elements of this instance.
boolean	compute(Vertex a, Vertex b, Vertex c)	Computes the circumcircle for the specified vertices and stores results in elements of this instance.
static Circumcircle	computeCircumcircle(Vertex a, Vertex b, Vertex c)	Computes the circumcircle for the specified vertices.
void	copy(Circumcircle c)	Copies the content of the specified circumcircle instance.
Rectangle2D	getBounds()	Gets the bounds of the circumcircle.
Vertex	getCircumcenter()	Gets a vertex representing the center of this circumcircle.
double	getRadius()	Gets the radius of the circumcircle
double	getRadiusSq()	Gets the square of the radius of the circumcircle.
double	getX()	Gets the x coordinate of the center of the circumcircle.
double	getY()	Gets the y coordinate of the center of the circumcircle.
void	setCircumcenter(double x, double y, double r2)	Sets the coordinate for the circumcenter and radius for this instance.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Circumcircle

public Circumcircle()

Standard constructor.

Method Detail

getRadiusSq

public double getRadiusSq()

Gets the square of the radius of the circumcircle.

Returns:

for a non-degenerate triangle, a positive floating point value (potentially Infinity for a ghost triangle).

getRadius

public double getRadius()

Gets the radius of the circumcircle

Returns:

for a non-degenerate triangle, a positive floating point value

getX

public double getX()

Gets the x coordinate of the center of the circumcircle.

Returns:

a valid floating point value.

getY

public double getY()

Gets the y coordinate of the center of the circumcircle.

Returns:

a valid floating point value.

getCircumcenter

public Vertex getCircumcenter()

Gets a vertex representing the center of this circumcircle.

Returns:

a valid vertex (with z coordinate set to NaN).

copy

public void copy(Circumcircle c)

Copies the content of the specified circumcircle instance.

Parameters:

c - a valid circumcircle instance.

computeCircumcircle

public static Circumcircle computeCircumcircle(Vertex a,
                                               Vertex b,
                                               Vertex c)

Computes the circumcircle for the specified vertices. Vertices are assumed to be given in counterclockwise order. Any null inputs for the vertices results in an infinite circumcircle. Vertices resulting in a degenerate (nearly zero area) triangle result in an infinite circumcircle.

Parameters:

a - the initial vertex.

b - the second vertex.

c - the third vertex.

Returns:

a valid circumcircle.

compute

public boolean compute(Vertex a,
                       Vertex b,
                       Vertex c)

Computes the circumcircle for the specified vertices and stores results in elements of this instance. Vertices are assumed to be given in counterclockwise order. Any null inputs for the vertices results in an infinite circumcircle. Vertices resulting in a degenerate (nearly zero area) triangle result in an infinite circumcircle.

Parameters:

a - the initial vertex.

b - the second vertex.

c - the third vertex.

Returns:

true if the computation successfully yields a circle of finite radius; otherwise, false.

compute

public void compute(double x0,
                    double y0,
                    double x1,
                    double y1,
                    double x2,
                    double y2)

Computes the circumcircle for the specified vertices and stores results in elements of this instance. Vertices are assumed to be given in counterclockwise order. Any null inputs for the vertices results in an infinite circumcircle. Vertices resulting in a degenerate (nearly zero area) triangle result in an infinite circumcircle.

Parameters:

x0 - the x coordinate of the first vertex

y0 - the y coordinate of the first vertex

x1 - the x coordinate of the second vertex

y1 - the y coordinate of the second vertex

x2 - the x coordinate of the third vertex

y2 - the y coordinate of the third vertex

setCircumcenter

public void setCircumcenter(double x,
                            double y,
                            double r2)

Sets the coordinate for the circumcenter and radius for this instance.

Parameters:

x - the x coordinate for the circumcenter

y - the y coordinate for the circumcenter

r2 - the square of the radius for the circumcircle

toString

public String toString()

Overrides:

toString in class Object

getBounds

public Rectangle2D getBounds()

Gets the bounds of the circumcircle.

Returns:

a valid rectangle instance.