com.badlogic.gdx.math

Class Matrix3

java.lang.Object

com.badlogic.gdx.math.Matrix3

All Implemented Interfaces:

Serializable

public class Matrix3
extends Object
implements Serializable

A 3x3 column major matrix; useful for 2D transforms.

Author:

mzechner

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static int	M00
static int	M01
static int	M02
static int	M10
static int	M11
static int	M12
static int	M20
static int	M21
static int	M22
float[]	val

Constructor Summary

Constructors

Constructor and Description
Matrix3()
Matrix3(float[] values) Constructs a matrix from the given float array.
Matrix3(Matrix3 matrix)

Method Summary

Methods

Modifier and Type	Method and Description
float	det()
float	getRotation()
float	getRotationRad()
Vector2	getScale(Vector2 scale)
Vector2	getTranslation(Vector2 position)
float[]	getValues() Get the values in this matrix.
Matrix3	idt() Sets this matrix to the identity matrix
Matrix3	inv() Inverts this matrix given that the determinant is != 0.
Matrix3	mul(Matrix3 m) Postmultiplies this matrix with the provided matrix and stores the result in this matrix.
Matrix3	mulLeft(Matrix3 m) Premultiplies this matrix with the provided matrix and stores the result in this matrix.
Matrix3	rotate(float degrees) Postmultiplies this matrix with a (counter-clockwise) rotation matrix.
Matrix3	rotateRad(float radians) Postmultiplies this matrix with a (counter-clockwise) rotation matrix.
Matrix3	scale(float scaleX, float scaleY) Postmultiplies this matrix with a scale matrix.
Matrix3	scale(Vector2 scale) Postmultiplies this matrix with a scale matrix.
Matrix3	scl(float scale) Scale the matrix in the both the x and y components by the scalar value.
Matrix3	scl(Vector2 scale) Scale this matrix using the x and y components of the vector but leave the rest of the matrix alone.
Matrix3	scl(Vector3 scale) Scale this matrix using the x and y components of the vector but leave the rest of the matrix alone.
Matrix3	set(float[] values) Sets the matrix to the given matrix as a float array.
Matrix3	set(Matrix3 mat) Copies the values from the provided matrix to this matrix.
Matrix3	set(Matrix4 mat) Sets this 3x3 matrix to the top left 3x3 corner of the provided 4x4 matrix.
Matrix3	setToRotation(float degrees) Sets this matrix to a rotation matrix that will rotate any vector in counter-clockwise direction around the z-axis.
Matrix3	setToRotation(Vector3 axis, float degrees)
Matrix3	setToRotation(Vector3 axis, float cos, float sin)
Matrix3	setToRotationRad(float radians) Sets this matrix to a rotation matrix that will rotate any vector in counter-clockwise direction around the z-axis.
Matrix3	setToScaling(float scaleX, float scaleY) Sets this matrix to a scaling matrix.
Matrix3	setToTranslation(float x, float y) Sets this matrix to a translation matrix.
Matrix3	setToTranslation(Vector2 translation) Sets this matrix to a translation matrix.
String	toString()
Matrix3	translate(float x, float y) Postmultiplies this matrix by a translation matrix.
Matrix3	translate(Vector2 translation) Postmultiplies this matrix by a translation matrix.
Matrix3	transpose() Transposes the current matrix.
Matrix3	trn(float x, float y) Adds a translational component to the matrix in the 3rd column.
Matrix3	trn(Vector2 vector) Adds a translational component to the matrix in the 3rd column.
Matrix3	trn(Vector3 vector) Adds a translational component to the matrix in the 3rd column.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

M00

public static final int M00

See Also:

Constant Field Values

M01

public static final int M01

See Also:

Constant Field Values

M02

public static final int M02

See Also:

Constant Field Values

M10

public static final int M10

See Also:

Constant Field Values

M11

public static final int M11

See Also:

Constant Field Values

M12

public static final int M12

See Also:

Constant Field Values

M20

public static final int M20

See Also:

Constant Field Values

M21

public static final int M21

See Also:

Constant Field Values

M22

public static final int M22

See Also:

Constant Field Values

val

public float[] val

Constructor Detail

Matrix3

public Matrix3()

Matrix3

public Matrix3(Matrix3 matrix)

Matrix3

public Matrix3(float[] values)

Constructs a matrix from the given float array. The array must have at least 9 elements; the first 9 will be copied.

Parameters:

values - The float array to copy. Remember that this matrix is in column major order. (The float array is not modified.)

Method Detail

idt

public Matrix3 idt()

Sets this matrix to the identity matrix

Returns:

This matrix for the purpose of chaining operations.

mul

public Matrix3 mul(Matrix3 m)

Postmultiplies this matrix with the provided matrix and stores the result in this matrix. For example:

 A.mul(B) results in A := AB
 

Parameters:

m - Matrix to multiply by.

Returns:

This matrix for the purpose of chaining operations together.

mulLeft

public Matrix3 mulLeft(Matrix3 m)

Premultiplies this matrix with the provided matrix and stores the result in this matrix. For example:

 A.mulLeft(B) results in A := BA
 

Parameters:

m - The other Matrix to multiply by

Returns:

This matrix for the purpose of chaining operations.

setToRotation

public Matrix3 setToRotation(float degrees)

Sets this matrix to a rotation matrix that will rotate any vector in counter-clockwise direction around the z-axis.

Parameters:

degrees - the angle in degrees.

Returns:

This matrix for the purpose of chaining operations.

setToRotationRad

public Matrix3 setToRotationRad(float radians)

Sets this matrix to a rotation matrix that will rotate any vector in counter-clockwise direction around the z-axis.

Parameters:

radians - the angle in degrees.

Returns:

This matrix for the purpose of chaining operations.

setToRotation

public Matrix3 setToRotation(Vector3 axis,
                    float degrees)

setToRotation

public Matrix3 setToRotation(Vector3 axis,
                    float cos,
                    float sin)

setToTranslation

public Matrix3 setToTranslation(float x,
                       float y)

Sets this matrix to a translation matrix.

Parameters:

x - the translation in x

y - the translation in y

Returns:

This matrix for the purpose of chaining operations.

setToTranslation

public Matrix3 setToTranslation(Vector2 translation)

Sets this matrix to a translation matrix.

Parameters:

translation - The translation vector.

Returns:

This matrix for the purpose of chaining operations.

setToScaling

public Matrix3 setToScaling(float scaleX,
                   float scaleY)

Sets this matrix to a scaling matrix.

Parameters:

scaleX - the scale in x

scaleY - the scale in y

Returns:

This matrix for the purpose of chaining operations.

toString

public String toString()

Overrides:

toString in class Object

det

public float det()

Returns:

The determinant of this matrix

inv

public Matrix3 inv()

Inverts this matrix given that the determinant is != 0.

Returns:

This matrix for the purpose of chaining operations.

Throws:

GdxRuntimeException - if the matrix is singular (not invertible)

set

public Matrix3 set(Matrix3 mat)

Copies the values from the provided matrix to this matrix.

Parameters:

mat - The matrix to copy.

Returns:

This matrix for the purposes of chaining.

set

public Matrix3 set(Matrix4 mat)

Sets this 3x3 matrix to the top left 3x3 corner of the provided 4x4 matrix.

Parameters:

mat - The matrix whose top left corner will be copied. This matrix will not be modified.

Returns:

This matrix for the purpose of chaining operations.

set

public Matrix3 set(float[] values)

Sets the matrix to the given matrix as a float array. The float array must have at least 9 elements; the first 9 will be copied.

Parameters:

values - The matrix, in float form, that is to be copied. Remember that this matrix is in column major order.

Returns:

This matrix for the purpose of chaining methods together.

trn

public Matrix3 trn(Vector2 vector)

Adds a translational component to the matrix in the 3rd column. The other columns are untouched.

Parameters:

vector - The translation vector.

Returns:

This matrix for the purpose of chaining.

trn

public Matrix3 trn(float x,
          float y)

Adds a translational component to the matrix in the 3rd column. The other columns are untouched.

Parameters:

x - The x-component of the translation vector.

y - The y-component of the translation vector.

Returns:

This matrix for the purpose of chaining.

trn

public Matrix3 trn(Vector3 vector)

Adds a translational component to the matrix in the 3rd column. The other columns are untouched.

Parameters:

vector - The translation vector. (The z-component of the vector is ignored because this is a 3x3 matrix)

Returns:

This matrix for the purpose of chaining.

translate

public Matrix3 translate(float x,
                float y)

Postmultiplies this matrix by a translation matrix. Postmultiplication is also used by OpenGL ES' 1.x glTranslate/glRotate/glScale.

Parameters:

x - The x-component of the translation vector.

y - The y-component of the translation vector.

Returns:

This matrix for the purpose of chaining.

translate

public Matrix3 translate(Vector2 translation)

Postmultiplies this matrix by a translation matrix. Postmultiplication is also used by OpenGL ES' 1.x glTranslate/glRotate/glScale.

Parameters:

translation - The translation vector.

Returns:

This matrix for the purpose of chaining.

rotate

public Matrix3 rotate(float degrees)

Postmultiplies this matrix with a (counter-clockwise) rotation matrix. Postmultiplication is also used by OpenGL ES' 1.x glTranslate/glRotate/glScale.

Parameters:

degrees - The angle in degrees

Returns:

This matrix for the purpose of chaining.

rotateRad

public Matrix3 rotateRad(float radians)

Postmultiplies this matrix with a (counter-clockwise) rotation matrix. Postmultiplication is also used by OpenGL ES' 1.x glTranslate/glRotate/glScale.

Parameters:

radians - The angle in degrees

Returns:

This matrix for the purpose of chaining.

scale

public Matrix3 scale(float scaleX,
            float scaleY)

Postmultiplies this matrix with a scale matrix. Postmultiplication is also used by OpenGL ES' 1.x glTranslate/glRotate/glScale.

Parameters:

scaleX - The scale in the x-axis.

scaleY - The scale in the y-axis.

Returns:

This matrix for the purpose of chaining.

scale

public Matrix3 scale(Vector2 scale)

Postmultiplies this matrix with a scale matrix. Postmultiplication is also used by OpenGL ES' 1.x glTranslate/glRotate/glScale.

Parameters:

scale - The vector to scale the matrix by.

Returns:

This matrix for the purpose of chaining.

getValues

public float[] getValues()

Get the values in this matrix.

Returns:

The float values that make up this matrix in column-major order.

getTranslation

public Vector2 getTranslation(Vector2 position)

getScale

public Vector2 getScale(Vector2 scale)

getRotation

public float getRotation()

getRotationRad

public float getRotationRad()

scl

public Matrix3 scl(float scale)

Scale the matrix in the both the x and y components by the scalar value.

Parameters:

scale - The single value that will be used to scale both the x and y components.

Returns:

This matrix for the purpose of chaining methods together.

scl

public Matrix3 scl(Vector2 scale)

Scale this matrix using the x and y components of the vector but leave the rest of the matrix alone.

Parameters:

scale - The Vector3 to use to scale this matrix.

Returns:

This matrix for the purpose of chaining methods together.

scl

public Matrix3 scl(Vector3 scale)

Scale this matrix using the x and y components of the vector but leave the rest of the matrix alone.

Parameters:

scale - The Vector3 to use to scale this matrix. The z component will be ignored.

Returns:

This matrix for the purpose of chaining methods together.

transpose

public Matrix3 transpose()

Transposes the current matrix.

Returns:

This matrix for the purpose of chaining methods together.