Object
- Rotation

All Implemented Interfaces:

Copyable<Rotation>
```
public class Rotation
extends Object
implements Copyable<Rotation>
```
This class represents a rotation (in 2D space). The aim of this class is to reduce as much as possible the use of trigonometric function calls (like Math.sin/cos or Math.atan2) because the majority of those are very slow to compute. This can be achieved by pre-computing the sin and cos of the angle of the rotation. A Rotation object is essentially a vector with norm 1. This class encapsulates the above so the user need not directly use and compute those trigonometric values. This also provides implicit validation as the user cannot create a Rotation with invalid values (values not derived from cos/sin of some angle). The receiver of a Rotation object can be sure it always represents a valid rotation.

Since:

3.4.0

Version:

4.0.0

Author:

Manolis Tsamis

Field Summary

Fields
Modifier and Type Field Description

protected double cost
The cosine of the angle described by this Rotation

protected double sint
The sine of the angle described by this Rotation

Constructor Summary

Constructors
Modifier	Constructor	Description
	`Rotation()`	Default constructor.
	`Rotation(double angle)`	Creates a `Rotation` from the given angle.
`protected`	`Rotation(double cost, double sint)`	Internal constructor that directly sets the cost and sint fields of the `Rotation` without additional validation.
	`Rotation(Rotation rotation)`	Copy constructor.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`compare(Rotation other)`	Compares this `Rotation` with another one, based on the angle between them (The one with -π ≤ θ ≤ π) Returns 1 if θ > 0, -1 if θ < 0 and 0 otherwise
`int`	`compare(Vector2 other)`	Compares this `Rotation` with a `Vector2`, based on the angle between them (The one with -π ≤ θ ≤ π) Returns 1 if θ > 0, -1 if θ < 0 and 0 otherwise
`Rotation`	`copy()`	Returns a deep copy of this object.
`double`	`cross(Rotation rotation)`	Returns the cross product of the this `Rotation` and the given `Rotation` which is essentially the sine of the angle between those rotations.
`double`	`dot(Rotation rotation)`	Returns the dot product of the this `Rotation` and the given `Rotation` which is essentially the sine of the angle between those rotations.
`boolean`	`equals(double angle)`	Returns true if the cos and sin components of this `Rotation` are the same as the given angle
`boolean`	`equals(double angle, double error)`	Returns true if the cos and sin components of this `Rotation` are the same as the given angle given the specified error.
`boolean`	`equals(Object obj)`
`boolean`	`equals(Rotation rotation)`	Returns true if the cos and sin components of this `Rotation` are the same as the given `Rotation`.
`boolean`	`equals(Rotation rotation, double error)`	Returns true if the cos and sin components of this `Rotation` are the same as the given `Rotation` given the specified error.
`double`	`getCost()`	Returns the value of cos(θ) for this `Rotation`.
`Rotation`	`getInversed()`	Negates this rotation and returns a new rotation.
`Rotation`	`getRotated(double angle)`	Rotates this rotation by the given angle and returns a new rotation.
`Rotation`	`getRotated(double c, double s)`	Internal method that return a new `Rotation` representing this `Rotation` after being rotated by an angle θ.
`Rotation`	`getRotated(Rotation rotation)`	Rotates this rotation by the given rotation and returns a new rotation.
`Rotation`	`getRotated135()`	Rotates this rotation 135 degrees and returns a new rotation.
`Rotation`	`getRotated180()`	Rotates this rotation 180 degrees and returns a new rotation.
`Rotation`	`getRotated225()`	Rotates this rotation 225 degrees and returns a new rotation.
`Rotation`	`getRotated270()`	Rotates this rotation 270 degrees and returns a new rotation.
`Rotation`	`getRotated315()`	Rotates this rotation 315 degrees and returns a new rotation.
`Rotation`	`getRotated45()`	Rotates this rotation 45 degrees and returns a new rotation.
`Rotation`	`getRotated90()`	Rotates this rotation 90 degrees and returns a new rotation.
`Rotation`	`getRotationBetween(Rotation rotation)`	Returns the angle between this and the given `Rotation` represented as a new `Rotation`.
`Rotation`	`getRotationBetween(Vector2 vector)`	Returns the angle between this `Rotation` and the given `Vector2` represented as a new `Rotation`.
`double`	`getSint()`	Returns the value of sin(θ) for this `Rotation`.
`int`	`hashCode()`
`Rotation`	`inverse()`	Negates this rotation and returns this rotation.
`boolean`	`isIdentity()`	Returns true if this rotation is an identity rotation.
`boolean`	`isIdentity(double error)`	Returns true if this rotation is an identity rotation within the given error.
`static Rotation`	`of(double angle)`	Alternative way to create a new `Rotation` from a given angle.
`static Rotation`	`of(double cost, double sint)`	Static method to create a `Rotation` from a pair of values that lie on the unit circle; That is a pair of values (x, y) such that x = cos(θ), y = sin(θ) for some value θ This method is provided for the case where the cos and sin values are already computed and the overhead can be avoided.
`static Rotation`	`of(Transform transform)`	Creates a new `Rotation` representing the same rotation of a `Transform` object.
`static Rotation`	`of(Vector2 direction)`	Static method to create a `Rotation` object from the direction of a given `Vector2`.
`static Rotation`	`ofDegrees(double angle)`	Alternative way to create a new `Rotation` from a given angle, in degrees.
`Rotation`	`rotate(double angle)`	Rotates this rotation by the given angle and returns this rotation.
`Rotation`	`rotate(Rotation rotation)`	Rotates this rotation by the given rotation and returns this rotation.
`Rotation`	`rotate135()`	Rotates this rotation 135 degrees and returns this rotation.
`Rotation`	`rotate180()`	Rotates this rotation 180 degrees and returns this rotation.
`Rotation`	`rotate225()`	Rotates this rotation 225 degrees and returns this rotation.
`Rotation`	`rotate270()`	Rotates this rotation 270 degrees and returns this rotation.
`Rotation`	`rotate315()`	Rotates this rotation 315 degrees and returns this rotation.
`Rotation`	`rotate45()`	Rotates this rotation 45 degrees and returns this rotation.
`Rotation`	`rotate90()`	Rotates this rotation 90 degrees and returns this rotation.
`static Rotation`	`rotation0()`	Creates a new `Rotation` of 0 degrees.
`static Rotation`	`rotation135()`	Creates a new `Rotation` of 135 degrees.
`static Rotation`	`rotation180()`	Creates a new `Rotation` of 180 degrees.
`static Rotation`	`rotation225()`	Creates a new `Rotation` of 225 degrees.
`static Rotation`	`rotation270()`	Creates a new `Rotation` of 270 degrees.
`static Rotation`	`rotation315()`	Creates a new `Rotation` of 315 degrees.
`static Rotation`	`rotation45()`	Creates a new `Rotation` of 45 degrees.
`static Rotation`	`rotation90()`	Creates a new `Rotation` of 90 degrees.
`Rotation`	`set(double angle)`	Sets this `Rotation` to the given angle.
`Rotation`	`set(Rotation rotation)`	Sets this `Rotation` to the given `Rotation`.
`Rotation`	`setIdentity()`	Sets this `Rotation` to be the identity.
`double`	`toDegrees()`	Returns the angle in degrees for this `Rotation`.
`double`	`toRadians()`	Returns the angle in radians for this `Rotation`.
`String`	`toString()`
`Vector2`	`toVector()`	Returns this `Rotation` as a unit length direction vector.
`Vector2`	`toVector(double magnitude)`	Returns this `Rotation` as a direction vector with the given magnitude.

Methods inherited from class Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - cost
```
protected double cost
```
    The cosine of the angle described by this Rotation
  - sint
```
protected double sint
```
    The sine of the angle described by this Rotation
- Constructor Detail
  - Rotation
```
protected Rotation(double cost,
                   double sint)
```
    Internal constructor that directly sets the cost and sint fields of the Rotation without additional validation.
    
    Parameters:
    
    cost - The cosine of some angle
    
    sint - The sine of the same angle
  - Rotation
```
public Rotation()
```
    Default constructor. Creates an identity Rotation.
  - Rotation
```
public Rotation(Rotation rotation)
```
    Copy constructor.
    
    Parameters:
    
    rotation - the Rotation to copy from
  - Rotation
```
public Rotation(double angle)
```
    Creates a Rotation from the given angle.
    
    Parameters:
    
    angle - the angle in radians
- Method Detail
  - of
```
public static Rotation of(double angle)
```
    Alternative way to create a new Rotation from a given angle.
    
    Parameters:
    
    angle - in radians
    
    Returns:
    
    A Rotation for that angle
  - ofDegrees
```
public static Rotation ofDegrees(double angle)
```
    Alternative way to create a new Rotation from a given angle, in degrees.
    
    Parameters:
    
    angle - in degrees
    
    Returns:
    
    A Rotation for that angle
  - of
```
public static Rotation of(Vector2 direction)
```
    Static method to create a Rotation object from the direction of a given Vector2.
    
    Parameters:
    
    direction - The Vector2 describing a direction
    
    Returns:
    
    A Rotation with the same direction
  - of
```
public static Rotation of(double cost,
                          double sint)
```
    Static method to create a Rotation from a pair of values that lie on the unit circle; That is a pair of values (x, y) such that x = cos(θ), y = sin(θ) for some value θ This method is provided for the case where the cos and sin values are already computed and the overhead can be avoided. This method will check whether those values are indeed on the unit circle and otherwise throw an IllegalArgumentException.
    
    Parameters:
    
    cost - The x value = cos(θ)
    
    sint - The y value = sin(θ)
    
    Returns:
    
    A Rotation defined by (cost, sint)
    
    Throws:
    
    IllegalArgumentException - if (cost, sint) is not on the unit circle
  - of
```
public static Rotation of(Transform transform)
```
    Creates a new Rotation representing the same rotation of a Transform object.
    
    Parameters:
    
    transform - The Transform
    
    Returns:
    
    A Rotation representing the same rotation
  - rotation0
```
public static Rotation rotation0()
```
    Creates a new Rotation of 0 degrees.
    
    Returns:
    
    Rotation
  - rotation90
```
public static Rotation rotation90()
```
    Creates a new Rotation of 90 degrees.
    
    Returns:
    
    Rotation
  - rotation180
```
public static Rotation rotation180()
```
    Creates a new Rotation of 180 degrees.
    
    Returns:
    
    Rotation
  - rotation270
```
public static Rotation rotation270()
```
    Creates a new Rotation of 270 degrees.
    
    Returns:
    
    Rotation
  - rotation45
```
public static Rotation rotation45()
```
    Creates a new Rotation of 45 degrees.
    
    Returns:
    
    Rotation
  - rotation135
```
public static Rotation rotation135()
```
    Creates a new Rotation of 135 degrees.
    
    Returns:
    
    Rotation
  - rotation225
```
public static Rotation rotation225()
```
    Creates a new Rotation of 225 degrees.
    
    Returns:
    
    Rotation
  - rotation315
```
public static Rotation rotation315()
```
    Creates a new Rotation of 315 degrees.
    
    Returns:
    
    Rotation
  - copy
```
public Rotation copy()
```
    Description copied from interface: Copyable
    
    Returns a deep copy of this object.
    
    Specified by:
    
    copy in interface Copyable<Rotation>
    
    Returns:
    
    T
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - equals
```
public boolean equals(Object obj)
```
    Overrides:
    
    equals in class Object
  - equals
```
public boolean equals(Rotation rotation)
```
    Returns true if the cos and sin components of this Rotation are the same as the given Rotation.
    
    Parameters:
    
    rotation - the Rotation to compare to
    
    Returns:
    
    boolean
  - equals
```
public boolean equals(Rotation rotation,
                      double error)
```
    Returns true if the cos and sin components of this Rotation are the same as the given Rotation given the specified error.
    
    Parameters:
    
    rotation - the Rotation to compare to
    
    error - the error
    
    Returns:
    
    boolean
  - equals
```
public boolean equals(double angle)
```
    Returns true if the cos and sin components of this Rotation are the same as the given angle
    
    Parameters:
    
    angle - the angle in radians
    
    Returns:
    
    boolean
  - equals
```
public boolean equals(double angle,
                      double error)
```
    Returns true if the cos and sin components of this Rotation are the same as the given angle given the specified error.
    
    Parameters:
    
    angle - the angle in radians
    
    error - the error
    
    Returns:
    
    boolean
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - set
```
public Rotation set(Rotation rotation)
```
    Sets this Rotation to the given Rotation.
    
    Parameters:
    
    rotation - the Rotation to set this Rotation to
    
    Returns:
    
    Rotation this rotation
  - setIdentity
```
public Rotation setIdentity()
```
    Sets this Rotation to be the identity.
    
    Returns:
    
    Rotation this rotation
  - set
```
public Rotation set(double angle)
```
    Sets this Rotation to the given angle.
    
    Parameters:
    
    angle - the angle in radians
    
    Returns:
    
    Rotation this rotation
  - getCost
```
public double getCost()
```
    Returns the value of cos(θ) for this Rotation.
    
    Returns:
    
    double
  - getSint
```
public double getSint()
```
    Returns the value of sin(θ) for this Rotation.
    
    Returns:
    
    double
  - toRadians
```
public double toRadians()
```
    Returns the angle in radians for this Rotation.
    
    Returns:
    
    double
  - toDegrees
```
public double toDegrees()
```
    Returns the angle in degrees for this Rotation.
    
    Returns:
    
    double
  - toVector
```
public Vector2 toVector()
```
    Returns this Rotation as a unit length direction vector.
    
    Returns:
    
    Vector2
  - toVector
```
public Vector2 toVector(double magnitude)
```
    Returns this Rotation as a direction vector with the given magnitude.
    
    Parameters:
    
    magnitude - the magnitude
    
    Returns:
    
    Vector2
  - rotate45
```
public Rotation rotate45()
```
    Rotates this rotation 45 degrees and returns this rotation.
    
    Returns:
    
    Rotation
  - getRotated45
```
public Rotation getRotated45()
```
    Rotates this rotation 45 degrees and returns a new rotation.
    
    Returns:
    
    Rotation
  - rotate90
```
public Rotation rotate90()
```
    Rotates this rotation 90 degrees and returns this rotation.
    
    Returns:
    
    Rotation
  - getRotated90
```
public Rotation getRotated90()
```
    Rotates this rotation 90 degrees and returns a new rotation.
    
    Returns:
    
    Rotation
  - rotate135
```
public Rotation rotate135()
```
    Rotates this rotation 135 degrees and returns this rotation.
    
    Returns:
    
    Rotation
  - getRotated135
```
public Rotation getRotated135()
```
    Rotates this rotation 135 degrees and returns a new rotation.
    
    Returns:
    
    Rotation
  - rotate180
```
public Rotation rotate180()
```
    Rotates this rotation 180 degrees and returns this rotation.
    
    Returns:
    
    Rotation
  - getRotated180
```
public Rotation getRotated180()
```
    Rotates this rotation 180 degrees and returns a new rotation.
    
    Returns:
    
    Rotation
  - rotate225
```
public Rotation rotate225()
```
    Rotates this rotation 225 degrees and returns this rotation.
    
    Returns:
    
    Rotation
  - getRotated225
```
public Rotation getRotated225()
```
    Rotates this rotation 225 degrees and returns a new rotation.
    
    Returns:
    
    Rotation
  - rotate270
```
public Rotation rotate270()
```
    Rotates this rotation 270 degrees and returns this rotation.
    
    Returns:
    
    Rotation
  - getRotated270
```
public Rotation getRotated270()
```
    Rotates this rotation 270 degrees and returns a new rotation.
    
    Returns:
    
    Rotation
  - rotate315
```
public Rotation rotate315()
```
    Rotates this rotation 315 degrees and returns this rotation.
    
    Returns:
    
    Rotation
  - getRotated315
```
public Rotation getRotated315()
```
    Rotates this rotation 315 degrees and returns a new rotation.
    
    Returns:
    
    Rotation
  - inverse
```
public Rotation inverse()
```
    Negates this rotation and returns this rotation.
    Let θ be the rotation, then -θ is the inverse rotation.
    
    Returns:
    
    Rotation
  - getInversed
```
public Rotation getInversed()
```
    Negates this rotation and returns a new rotation.
    Let θ be the rotation, then -θ is the inverse rotation.
    
    Returns:
    
    Rotation
  - getRotated
```
public Rotation getRotated(double c,
                           double s)
```
    Internal method that return a new Rotation representing this Rotation after being rotated by an angle θ.
    
    Parameters:
    
    c - cos(θ)
    
    s - sin(θ)
    
    Returns:
    
    Rotation
  - rotate
```
public Rotation rotate(Rotation rotation)
```
    Rotates this rotation by the given rotation and returns this rotation.
    
    Parameters:
    
    rotation - the Rotation
    
    Returns:
    
    Rotation
  - getRotated
```
public Rotation getRotated(Rotation rotation)
```
    Rotates this rotation by the given rotation and returns a new rotation.
    
    Parameters:
    
    rotation - the Rotation
    
    Returns:
    
    Rotation
  - rotate
```
public Rotation rotate(double angle)
```
    Rotates this rotation by the given angle and returns this rotation.
    
    Parameters:
    
    angle - the rotation in radians
    
    Returns:
    
    Rotation
  - getRotated
```
public Rotation getRotated(double angle)
```
    Rotates this rotation by the given angle and returns a new rotation.
    
    Parameters:
    
    angle - the rotation in radians
    
    Returns:
    
    Rotation
  - isIdentity
```
public boolean isIdentity()
```
    Returns true if this rotation is an identity rotation.
    
    Returns:
    
    boolean
  - isIdentity
```
public boolean isIdentity(double error)
```
    Returns true if this rotation is an identity rotation within the given error.
    
    Parameters:
    
    error - the error
    
    Returns:
    
    boolean
  - dot
```
public double dot(Rotation rotation)
```
    Returns the dot product of the this Rotation and the given Rotation which is essentially the sine of the angle between those rotations.
    
    Parameters:
    
    rotation - the Rotation
    
    Returns:
    
    double
  - cross
```
public double cross(Rotation rotation)
```
    Returns the cross product of the this Rotation and the given Rotation which is essentially the sine of the angle between those rotations.
    
    Parameters:
    
    rotation - the Rotation
    
    Returns:
    
    double
  - compare
```
public int compare(Rotation other)
```
    Compares this Rotation with another one, based on the angle between them (The one with -π ≤ θ ≤ π) Returns 1 if θ > 0, -1 if θ < 0 and 0 otherwise
    
    Parameters:
    
    other - the Rotation to compare to
    
    Returns:
    
    int
  - compare
```
public int compare(Vector2 other)
```
    Compares this Rotation with a Vector2, based on the angle between them (The one with -π ≤ θ ≤ π) Returns 1 if θ > 0, -1 if θ < 0 and 0 otherwise
    
    Parameters:
    
    other - the Vector2 to compare to
    
    Returns:
    
    int
  - getRotationBetween
```
public Rotation getRotationBetween(Rotation rotation)
```
    Returns the angle between this and the given Rotation represented as a new Rotation.
    
    Parameters:
    
    rotation - the Rotation
    
    Returns:
    
    Rotation
  - getRotationBetween
```
public Rotation getRotationBetween(Vector2 vector)
```
    Returns the angle between this Rotation and the given Vector2 represented as a new Rotation.
    
    Parameters:
    
    vector - the Vector2
    
    Returns:
    
    Rotation

Modifier and Type	Field	Description
`protected double`	`cost`	The cosine of the angle described by this Rotation
`protected double`	`sint`	The sine of the angle described by this Rotation

Class Rotation

Field Summary

Constructor Summary

Method Summary

Methods inherited from class Object

Field Detail

cost

sint

Constructor Detail

Rotation

Rotation

Rotation

Rotation

Method Detail

of

ofDegrees

of

of

of

rotation0

rotation90

rotation180

rotation270

rotation45

rotation135

rotation225

rotation315

copy

hashCode

equals

equals

equals

equals

equals

toString

set

setIdentity

set

getCost

getSint

toRadians

toDegrees

toVector

toVector

rotate45

getRotated45

rotate90

getRotated90

rotate135

getRotated135

rotate180

getRotated180

rotate225

getRotated225

rotate270

getRotated270

rotate315

getRotated315

inverse

getInversed

getRotated

rotate

getRotated

rotate

getRotated

isIdentity

isIdentity

dot

cross

compare

compare

getRotationBetween

getRotationBetween