com.threerings.math
Class Line

java.lang.Object
  com.threerings.math.Line

public class Line
extends Object

A line consisting of a unit normal and a constant. All points on the line satisfy the equation Ax + By + C = 0, where (A, B) is the line normal and C is the constant.

Field Summary

float	constant The line constant.
static Line	X_AXIS The X axis.
static Line	Y_AXIS The Y axis.

Constructor Summary

Line()
Creates an empty (invalid) line.

Line(float a, float b, float c)
Creates a line with the specified parameters.

Line(Line other)
Copy constructor.

Line(Vector2f normal, float constant)
Creates a line from the specified normal and constant.

Method Summary

boolean	equals(Object other)
Line	fromPoints(Vector2f p1, Vector2f p2) Sets this line based on the two points provided.
float	getDistance(Ray2D ray) Computes the signed distance to this line along the specified ray.
float	getDistance(Vector2f pt) Computes and returns the signed distance from the line to the specified point.
boolean	getIntersection(Ray2D ray, Vector2f result) Computes the intersection of the supplied ray with this line, placing the result in the given vector (if the ray intersects).
Vector2f	getNormal() Returns a reference to the line normal.
int	hashCode()
Line	set(float a, float b, float c) Sets the parameters of the line.
Line	set(Line other) Copies the parameters of another line.
Line	set(Vector2f normal, float constant) Sets the parameters of the line.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, toString, wait, wait, wait

Field Detail

X_AXIS

public static final Line X_AXIS

The X axis.

Y_AXIS

public static final Line Y_AXIS

The Y axis.

constant

public float constant

The line constant.

Constructor Detail

Line

public Line(Vector2f normal,
            float constant)

Creates a line from the specified normal and constant.

Line

public Line(float a,
            float b,
            float c)

Creates a line with the specified parameters.

Line

public Line(Line other)

Copy constructor.

Line

public Line()

Creates an empty (invalid) line.

Method Detail

getNormal

public Vector2f getNormal()

Returns a reference to the line normal.

fromPoints

public Line fromPoints(Vector2f p1,
                       Vector2f p2)

Sets this line based on the two points provided.

Returns:

a reference to the line (for chaining).

set

public Line set(Line other)

Copies the parameters of another line.

Returns:

a reference to this line (for chaining).

set

public Line set(Vector2f normal,
                float constant)

Sets the parameters of the line.

Returns:

a reference to this line (for chaining).

set

public Line set(float a,
                float b,
                float c)

Sets the parameters of the line.

Returns:

a reference to this line (for chaining).

getIntersection

public boolean getIntersection(Ray2D ray,
                               Vector2f result)

Computes the intersection of the supplied ray with this line, placing the result in the given vector (if the ray intersects).

Returns:

true if the ray intersects the line (in which case the result will contain the point of intersection), false if not.

getDistance

public float getDistance(Ray2D ray)

Computes the signed distance to this line along the specified ray.

Returns:

the signed distance, or {Float#NaN} if the ray runs parallel to the line.

getDistance

public float getDistance(Vector2f pt)

Computes and returns the signed distance from the line to the specified point.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object other)

Overrides:

equals in class Object