sim.util

Class Rotation2D

java.lang.Object

sim.util.Rotation2D

All Implemented Interfaces:

Serializable, Comparable<Rotation2D>

@XStreamConverter(value=Rotation2D.MyConverter.class)
public final class Rotation2D
extends Object
implements Comparable<Rotation2D>, Serializable

A two-dimensional rotation. It is represented as a unit vector

 (cos(theta), sin(theta))
 

where theta is the angle.

Objects of this class are immutable.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Rotation2D.MyConverter

Field Summary

Fields

Modifier and Type	Field and Description
static Rotation2D	EIGHTH The rotation of an eighth revolution.
static Rotation2D	HALF The rotation of a half revolution.
static Rotation2D	QUARTER The rotation of a quarter revolution.
static Rotation2D	ZERO The identity rotation.

Method Summary

Modifier and Type	Method and Description
int	compareTo(Rotation2D o)
boolean	equals(Object obj)
static Rotation2D	fromAngle(double theta) Returns the rotation which is equal to the given angle.
static Rotation2D	fromBetween(Double2D direction1, Double2D direction2) Creates a rotation from direction1 to direction2.
static Rotation2D	fromVector(Double2D vector) Creates a rotation from a direction vector.
double	getCos() Returns the cosine of this rotation.
double	getSin() Returns the sine of this rotation.
Double2D	getVector() Returns the rotation as direction vector.
int	hashCode()
boolean	isClockwise() Returns true if the shortest path following this rotation is clockwise.
Double2D	multiply(Double2D vector) Applies this rotation on a vector by rotating around its origin.
Rotation2D	multiply(Rotation2D other) Concatenates this rotation with another rotation.
Rotation2D	nlerp(Rotation2D other, double t) Performs a linear interpolation between the vectors of this rotation and the other.
Rotation2D	opposite() Returns the opposite of this direction.
Rotation2D	slerp(Rotation2D other, double t) Performs a spherical linear interpolation between this rotation and the other.
double	toAngle() Returns the angle of this rotation in radians.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

ZERO

public static final Rotation2D ZERO

The identity rotation. It will not change the orientation of a vector when applied.

EIGHTH

public static final Rotation2D EIGHTH

The rotation of an eighth revolution.

QUARTER

public static final Rotation2D QUARTER

The rotation of a quarter revolution.

HALF

public static final Rotation2D HALF

The rotation of a half revolution.

Method Detail

multiply

public Rotation2D multiply(Rotation2D other)

Concatenates this rotation with another rotation. This operation is commutative.

Parameters:

other - the other rotation

Returns:

the concatenated rotation

multiply

public Double2D multiply(Double2D vector)

Applies this rotation on a vector by rotating around its origin.

Parameters:

vector - the vector to rotate

Returns:

the rotated vector

opposite

public Rotation2D opposite()

Returns the opposite of this direction.

Returns:

the opposite of this rotation

nlerp

public Rotation2D nlerp(Rotation2D other,
                        double t)

Performs a linear interpolation between the vectors of this rotation and the other. The normalized result is used to create a valid rotation.

Parameters:

other - the other rotation

t - the interpolation parameter

Returns:

the resulting rotation

Throws:

ArithmeticException - if rotations are opposite

slerp

public Rotation2D slerp(Rotation2D other,
                        double t)

Performs a spherical linear interpolation between this rotation and the other. If the other rotation is opposite to this, the interpolation takes place clockwise.

Parameters:

other - the other rotation

t - the interpolation parameter

Returns:

the resulting rotation

isClockwise

public boolean isClockwise()

Returns true if the shortest path following this rotation is clockwise. Otherwise, false is returned

Returns:

true if clockwise

toAngle

public double toAngle()

Returns the angle of this rotation in radians.

Returns:

the angle of this rotation

getVector

public Double2D getVector()

Returns the rotation as direction vector.

Returns:

the direction vector

fromAngle

public static Rotation2D fromAngle(double theta)

Returns the rotation which is equal to the given angle.

Parameters:

theta - the angle in radians

Returns:

the rotation equal to the given angle

fromVector

public static Rotation2D fromVector(Double2D vector)

Creates a rotation from a direction vector. The result is the rotation between the direction vector (1,0) and the given one.

NOTE: The vector must be of unit length. Otherwise the resulting rotation is invalid.

Parameters:

vector - the direction unit vector

Returns:

the rotation object

fromBetween

public static Rotation2D fromBetween(Double2D direction1,
                                     Double2D direction2)

Creates a rotation from direction1 to direction2.

NOTE: Both vectors must be of unit length. Otherwise the resulting rotation is invalid.

Parameters:

direction1 -

direction2 -

Returns:

the rotation between both vectors

getCos

public double getCos()

Returns the cosine of this rotation.

Returns:

the cosine of this rotation

getSin

public double getSin()

Returns the sine of this rotation.

Returns:

the sine of this rotation

compareTo

public int compareTo(Rotation2D o)

Specified by:

compareTo in interface Comparable<Rotation2D>

toString

public String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object