org.cell2d

Class CellVector

java.lang.Object

org.cell2d.CellVector

public class CellVector
extends java.lang.Object

A CellVector represents a point in continuous space as a two-dimensional vector. CellVectors are mutable; that is, the point that they represent can be changed. However, since the point that a CellVector represents is the basis of its equals() and hashCode() methods, care must be taken not to mutate a CellVector while data structures such as Maps or Sets are using it. CellVectors measure angles in degrees going counterclockwise from directly right and normalize them to be between 0 and 360. All operations on a CellVector return the CellVector itself to allow operations to be easily strung together.

Constructor Summary

Constructors

Constructor and Description
CellVector() Constructs a CellVector that represents the origin.
CellVector(CellVector point) Constructs a CellVector that represents the specified point.
CellVector(double angle) Constructs a CellVector that represents the point on the unit circle at the specified angle from the origin.
CellVector(long x, long y) Constructs a CellVector that represents the specified point.

Method Summary

Modifier and Type	Method and Description
CellVector	add(CellVector vector) Adds the specified CellVector to this CellVector.
static CellVector	add(CellVector first, CellVector second) Returns a new CellVector that represents the sum of the two specified CellVectors.
CellVector	add(long x, long y) Adds the specified coordinates to this CellVector's own.
static double	angleBetween(long x1, long y1, long x2, long y2) Returns the angle from the point (x1, y1) to the point (x2, y2).
double	angleTo(CellVector point) Returns the angle from this CellVector's point to that of the specified CellVector.
CellVector	changeAngle(double angle) Changes this CellVector's angle by the specified amount while retaining its magnitude.
CellVector	clear() Resets this CellVector to represent the origin.
long	cross(CellVector vector) Returns the non-zero component in fracunits of the cross product of this CellVector and the specified one.
static long	distanceBetween(long x1, long y1, long x2, long y2) Returns the distance between the points (x1, y1) and (x2, y2).
long	distanceTo(CellVector point) Returns the distance from this CellVector's point to that of the specified CellVector.
long	dot(CellVector vector) Returns the dot product in fracunits of this CellVector and the specified one.
boolean	equals(java.lang.Object obj) Returns whether the specified object is a CellVector that is equal to this CellVector.
CellVector	flip() Flips this CellVector across both coordinate axes, negating both of its coordinates.
CellVector	flip(boolean xFlip, boolean yFlip) Flips this CellVector across either, both, or neither of the coordinate axes, depending on the parameters.
CellVector	flipX() Flips this CellVector across the x-axis, negating its x-coordinate.
CellVector	flipY() Flips this CellVector across the y-axis, negating its y-coordinate.
double	getAngle() Returns this CellVector's angle.
long	getAngleX() Returns the x-coordinate of the unit vector that points in the direction of this CellVector's angle.
long	getAngleY() Returns the y-coordinate of the unit vector that points in the direction of this CellVector's angle.
long	getMagnitude() Returns this CellVector's magnitude.
long	getMagnitudeSquared() Returns the square of this CellVector's magnitude.
long	getX() Returns the x-coordinate of the point that this CellVector represents.
long	getY() Returns the y-coordinate of the point that this CellVector represents.
int	hashCode()
static boolean	lineSegmentsIntersect(CellVector start1, CellVector diff1, CellVector start2, CellVector diff2) Returns whether the two specified line segments share any points.
static CellVector	lineSegmentsIntersectionPoint(CellVector start1, CellVector diff1, CellVector start2, CellVector diff2) Returns the single point at which the two specified line segments intersect, or null if they intersect at no points or at an infinity of points.
CellVector	relativeTo(Hitbox hitbox) Flips this CellVector to reflect the flipped status of the specified Hitbox and rotates it to reflect the Hitbox's angle of rotation, as if those properties were formerly relative to the Hitbox.
CellVector	relativeTo(SpaceObject object) Flips this CellVector to reflect the flipped status of the specified SpaceObject and rotates it to reflect the SpaceObject's angle of rotation, as if those properties were formerly relative to the SpaceObject.
CellVector	scale(long scaleFactor) Multiplies this CellVector's coordinates by the specified fracunit-scale factor.
CellVector	setAngle(double angle) Sets this CellVector's angle to the specified value while retaining its magnitude.
CellVector	setCoordinates(CellVector point) Sets this CellVector's point to the specified value.
CellVector	setCoordinates(long x, long y) Sets this CellVector's point to the specified coordinates.
CellVector	setMagnitude(long magnitude) Sets this CellVector's magnitude to the specified value while retaining its angle.
CellVector	setX(long x) Sets the x-coordinate of this CellVector's point to the specified value.
CellVector	setY(long y) Sets the y-coordinate of this CellVector's point to the specified value.
CellVector	sub(CellVector vector) Subtracts the specified CellVector from this CellVector.
static CellVector	sub(CellVector first, CellVector second) Returns a new CellVector that represents the second specified CellVector subtracted from the first.
CellVector	sub(long x, long y) Subtracts the specified coordinates from this CellVector's own.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CellVector

public CellVector()

Constructs a CellVector that represents the origin.

CellVector

public CellVector(CellVector point)

Constructs a CellVector that represents the specified point.

Parameters:

point - The point that this CellVector represents

CellVector

public CellVector(long x,
                  long y)

Constructs a CellVector that represents the specified point.

Parameters:

x - The x-coordinate of the point that this CellVector represents

y - The y-coordinate of the point that this CellVector represents

CellVector

public CellVector(double angle)

Constructs a CellVector that represents the point on the unit circle at the specified angle from the origin.

Parameters:

angle - The angle from the origin of the point on the unit circle that this CellVector represents

Method Detail

hashCode

public final int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public final boolean equals(java.lang.Object obj)

Returns whether the specified object is a CellVector that is equal to this CellVector. Two CellVectors are equal if and only if they represent the same point.

Overrides:

equals in class java.lang.Object

Parameters:

obj - The object to be compared with this CellVector

Returns:

Whether the specified object is a CellVector that is equal to this CellVector

clear

public final CellVector clear()

Resets this CellVector to represent the origin.

Returns:

This CellVector

getX

public final long getX()

Returns the x-coordinate of the point that this CellVector represents.

Returns:

The x-coordinate of the point that this CellVector represents

setX

public final CellVector setX(long x)

Sets the x-coordinate of this CellVector's point to the specified value.

Parameters:

x - The point's new x-coordinate

Returns:

This CellVector

getY

public final long getY()

Returns the y-coordinate of the point that this CellVector represents.

Returns:

The y-coordinate of the point that this CellVector represents

setY

public final CellVector setY(long y)

Sets the y-coordinate of this CellVector's point to the specified value.

Parameters:

y - The point's new y-coordinate

Returns:

This CellVector

setCoordinates

public final CellVector setCoordinates(CellVector point)

Sets this CellVector's point to the specified value.

Parameters:

point - The new point

Returns:

This CellVector

setCoordinates

public final CellVector setCoordinates(long x,
                                       long y)

Sets this CellVector's point to the specified coordinates.

Parameters:

x - The point's new x-coordinate

y - The point's new y-coordinate

Returns:

This CellVector

flip

public final CellVector flip()

Flips this CellVector across both coordinate axes, negating both of its coordinates.

Returns:

This CellVector

flipX

public final CellVector flipX()

Flips this CellVector across the x-axis, negating its x-coordinate.

Returns:

This CellVector

flipY

public final CellVector flipY()

Flips this CellVector across the y-axis, negating its y-coordinate.

Returns:

This CellVector

flip

public final CellVector flip(boolean xFlip,
                             boolean yFlip)

Flips this CellVector across either, both, or neither of the coordinate axes, depending on the parameters.

Parameters:

xFlip - If true, this CellVector will be flipped across the x-axis

yFlip - If true, this CellVector will be flipped across the y-axis

Returns:

This CellVector

getMagnitudeSquared

public final long getMagnitudeSquared()

Returns the square of this CellVector's magnitude.

Returns:

The square of this CellVector's magnitude

getMagnitude

public final long getMagnitude()

Returns this CellVector's magnitude.

Returns:

This CellVector's magnitude

setMagnitude

public final CellVector setMagnitude(long magnitude)

Sets this CellVector's magnitude to the specified value while retaining its angle. If the new magnitude is negative, this CellVector will be flipped and its magnitude set to the absolute value of the specified magnitude.

Parameters:

magnitude - The new magnitude

Returns:

This CellVector

scale

public final CellVector scale(long scaleFactor)

Multiplies this CellVector's coordinates by the specified fracunit-scale factor.

Parameters:

scaleFactor - The factor by which to scale this CellVector

Returns:

This CellVector

getAngle

public final double getAngle()

Returns this CellVector's angle.

Returns:

This CellVector's angle

getAngleX

public final long getAngleX()

Returns the x-coordinate of the unit vector that points in the direction of this CellVector's angle. This is equal to the cosine of the angle.

Returns:

The x-coordinate of this CellVector's angle

getAngleY

public final long getAngleY()

Returns the y-coordinate of the unit vector that points in the direction of this CellVector's angle. Since y-coordinates increase going downward, this is equal to the negative sine of the angle.

Returns:

The y-coordinate of this CellVector's angle

setAngle

public final CellVector setAngle(double angle)

Sets this CellVector's angle to the specified value while retaining its magnitude.

Parameters:

angle - The new angle

Returns:

This CellVector

changeAngle

public final CellVector changeAngle(double angle)

Changes this CellVector's angle by the specified amount while retaining its magnitude.

Parameters:

angle - The amount by which to change the angle

Returns:

This CellVector

add

public final CellVector add(CellVector vector)

Adds the specified CellVector to this CellVector.

Parameters:

vector - The CellVector to be added

Returns:

This CellVector

add

public final CellVector add(long x,
                            long y)

Adds the specified coordinates to this CellVector's own.

Parameters:

x - The x-coordinate to be added

y - The y-coordinate to be added

Returns:

This CellVector

add

public static CellVector add(CellVector first,
                             CellVector second)

Returns a new CellVector that represents the sum of the two specified CellVectors.

Parameters:

first - The first CellVector

second - The second CellVector

Returns:

The sum of the two CellVectors

sub

public final CellVector sub(CellVector vector)

Subtracts the specified CellVector from this CellVector.

Parameters:

vector - The CellVector to be subtracted

Returns:

This CellVector

sub

public final CellVector sub(long x,
                            long y)

Subtracts the specified coordinates from this CellVector's own.

Parameters:

x - The x-coordinate to be subtracted

y - The y-coordinate to be subtracted

Returns:

This CellVector

sub

public static CellVector sub(CellVector first,
                             CellVector second)

Returns a new CellVector that represents the second specified CellVector subtracted from the first.

Parameters:

first - The first CellVector

second - The second CellVector

Returns:

The second CellVector subtracted from the first

dot

public final long dot(CellVector vector)

Returns the dot product in fracunits of this CellVector and the specified one.

Parameters:

vector - The CellVector to take the dot product with

Returns:

The dot product of this CellVector and the specified one

cross

public final long cross(CellVector vector)

Returns the non-zero component in fracunits of the cross product of this CellVector and the specified one.

Parameters:

vector - The CellVector to take the cross product with

Returns:

The non-zero component of the cross product of this CellVector and the specified one

relativeTo

public final CellVector relativeTo(Hitbox hitbox)

Flips this CellVector to reflect the flipped status of the specified Hitbox and rotates it to reflect the Hitbox's angle of rotation, as if those properties were formerly relative to the Hitbox.

Parameters:

hitbox - The Hitbox to reflect

Returns:

This CellVector

relativeTo

public final CellVector relativeTo(SpaceObject object)

Flips this CellVector to reflect the flipped status of the specified SpaceObject and rotates it to reflect the SpaceObject's angle of rotation, as if those properties were formerly relative to the SpaceObject.

Parameters:

object - The SpaceObject to reflect

Returns:

This CellVector

distanceTo

public final long distanceTo(CellVector point)

Returns the distance from this CellVector's point to that of the specified CellVector.

Parameters:

point - The point to return the distance to

Returns:

The distance from this CellVector's point to that of the specified CellVector

distanceBetween

public static long distanceBetween(long x1,
                                   long y1,
                                   long x2,
                                   long y2)

Returns the distance between the points (x1, y1) and (x2, y2).

Parameters:

x1 - The x-coordinate of the first point

y1 - The y-coordinate of the first point

x2 - The x-coordinate of the second point

y2 - The y-coordinate of the second point

Returns:

The distance between (x1, y1) and (x2, y2)

angleTo

public final double angleTo(CellVector point)

Returns the angle from this CellVector's point to that of the specified CellVector.

Parameters:

point - The point to return the angle to

Returns:

The angle from this CellVector's point to that of the specified CellVector

angleBetween

public static double angleBetween(long x1,
                                  long y1,
                                  long x2,
                                  long y2)

Returns the angle from the point (x1, y1) to the point (x2, y2).

Parameters:

x1 - The x-coordinate of the first point

y1 - The y-coordinate of the first point

x2 - The x-coordinate of the second point

y2 - The y-coordinate of the second point

Returns:

The angle from (x1, y1) to (x2, y2)

lineSegmentsIntersect

public static boolean lineSegmentsIntersect(CellVector start1,
                                            CellVector diff1,
                                            CellVector start2,
                                            CellVector diff2)

Returns whether the two specified line segments share any points. The line segments do not contain their own endpoints.

Parameters:

start1 - One of the first line segment's endpoints

diff1 - The difference of the first line segment's endpoints

start2 - One of the second line segment's endpoints

diff2 - The difference of the second line segment's endpoints

Returns:

Whether the two line segments intersect

lineSegmentsIntersectionPoint

public static CellVector lineSegmentsIntersectionPoint(CellVector start1,
                                                       CellVector diff1,
                                                       CellVector start2,
                                                       CellVector diff2)

Returns the single point at which the two specified line segments intersect, or null if they intersect at no points or at an infinity of points. The line segments do not contain their own endpoints.

Parameters:

start1 - One of the first line segment's endpoints

diff1 - The difference of the first line segment's endpoints

start2 - One of the second line segment's endpoints

diff2 - The difference of the second line segment's endpoints

Returns:

The point at which the two line segments intersect