Package com.jme3.math

Class Matrix4f

java.lang.Object

com.jme3.math.Matrix4f

All Implemented Interfaces:

Cloneable

public final class Matrix4f
extends Object
implements Cloneable

A 4x4 matrix composed of 16 single-precision elements, used to represent linear or perspective transformations of 3-D coordinates.

The rightmost column (column 3) stores the translation vector. Element numbering is (row,column), so m03 is the row 0, column 3, which is the X translation.

Methods with names ending in "Local" modify the current instance. They are used to avoid creating garbage.

Field Summary

Fields

Modifier and Type	Field	Description
float	m00	The element in row 0, column 0.
float	m01	The element in row 0, column 1.
float	m02	The element in row 0, column 2.
float	m03	The element in row 0, column 3 (the X translation).
float	m10	The element in row 1, column 0.
float	m11	The element in row 1, column 1.
float	m12	The element in row 1, column 2.
float	m13	The element in row 1, column 3 (the Y translation).
float	m20	The element in row 2, column 0.
float	m21	The element in row 2, column 1.
float	m22	The element in row 2, column 2.
float	m23	The element in row 2, column 3 (the Z translation).
float	m30	The element in row 3, column 0.
float	m31	The element in row 3, column 1.
float	m32	The element in row 3, column 2.
float	m33	The element in row 3, column 3.

Constructor Summary

Constructors

Constructor	Description
Matrix4f()	Instantiates an identity matrix (diagonals = 1, other elements = 0).

Method Summary

Modifier and Type	Method	Description
Matrix4f	clone()	Creates a copy.
boolean	equals(Object o)	Tests for exact equality with the argument, distinguishing -0 from 0.
int	hashCode()	Returns a hash code.
Matrix4f	invertLocal()	Inverts in place.
void	loadIdentity()	Configures as an identity matrix (diagonals = 1, other elements = 0).
void	multLocal(float scalar)	Multiplies in place by the scalar argument.
void	setScale(float x, float y, float z)	Alters the scale component of the coordinate transform.
void	setScale(Vector3f scale)	Alters the scale component of the coordinate transform.
void	setTranslation(Vector3f translation)	Alters the translation component of the coordinate transform.
void	toRotationMatrix(Matrix3f mat)	Determines the rotation component of the coordinate transform.
Quaternion	toRotationQuat(Quaternion q)	Returns the rotation component of the coordinate transform.
Vector3f	toScaleVector(Vector3f store)	Determines the scale component of the coordinate transform.
String	toString()	Returns a string representation of the matrix, which is unaffected.
Vector3f	toTranslationVector(Vector3f vector)	Returns the translation component of the coordinate transform.
Matrix4f	zero()	Sets all elements to zero.

Methods inherited from class java.lang.Object

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

Field Details

m00

public float m00

The element in row 0, column 0.

m01

public float m01

The element in row 0, column 1.

m02

public float m02

The element in row 0, column 2.

m03

public float m03

The element in row 0, column 3 (the X translation).

m10

public float m10

The element in row 1, column 0.

m11

public float m11

The element in row 1, column 1.

m12

public float m12

The element in row 1, column 2.

m13

public float m13

The element in row 1, column 3 (the Y translation).

m20

public float m20

The element in row 2, column 0.

m21

public float m21

The element in row 2, column 1.

m22

public float m22

The element in row 2, column 2.

m23

public float m23

The element in row 2, column 3 (the Z translation).

m30

public float m30

The element in row 3, column 0.

m31

public float m31

The element in row 3, column 1.

m32

public float m32

The element in row 3, column 2.

m33

public float m33

The element in row 3, column 3.

Constructor Details

Matrix4f

public Matrix4f()

Instantiates an identity matrix (diagonals = 1, other elements = 0).

Method Details

loadIdentity

public void loadIdentity()

Configures as an identity matrix (diagonals = 1, other elements = 0).

multLocal

public void multLocal(float scalar)

Multiplies in place by the scalar argument.

Parameters:

scalar - the scaling factor to apply to all elements

invertLocal

public Matrix4f invertLocal()

Inverts in place. If the current instance is singular, the matrix is zeroed.

Returns:

the (inverted) current instance (for chaining)

zero

public Matrix4f zero()

Sets all elements to zero.

Returns:

the (modified) current instance (for chaining)

toTranslationVector

public Vector3f toTranslationVector(Vector3f vector)

Returns the translation component of the coordinate transform.

Parameters:

vector - storage for the result (not null, modified)

Returns:

the translation component (in vector) for chaining

toRotationQuat

public Quaternion toRotationQuat(Quaternion q)

Returns the rotation component of the coordinate transform.

Assumes (but does not verify) that the transform consists entirely of translation, rotation, and positive scaling -- no reflection or shear.

Parameters:

q - storage for the result (not null, modified)

Returns:

the rotation component (in q) for chaining

toRotationMatrix

public void toRotationMatrix(Matrix3f mat)

Determines the rotation component of the coordinate transform.

If the transform includes scaling or reflection or shear, the result might not be a valid rotation matrix.

Parameters:

mat - storage for the result (not null, modified)

toScaleVector

public Vector3f toScaleVector(Vector3f store)

Determines the scale component of the coordinate transform.

All components of the result will be non-negative, even if the coordinate transform includes reflection.

Parameters:

store - storage for the result (not null, modified)

Returns:

the scale factors (in store) for chaining

setScale

public void setScale(float x,
 float y,
 float z)

Alters the scale component of the coordinate transform.

Parameters:

x - the desired scale factor for the X axis

y - the desired scale factor for the Y axis

z - the desired scale factor for the Z axis

setScale

public void setScale(Vector3f scale)

Alters the scale component of the coordinate transform.

Parameters:

scale - the desired scale factors (not null, unaffected)

setTranslation

public void setTranslation(Vector3f translation)

Alters the translation component of the coordinate transform.

Parameters:

translation - the desired translation (not null, unaffected)

toString

public String toString()

Returns a string representation of the matrix, which is unaffected. For example, the identity matrix is represented by:

 Matrix4f
 [
  1.0  0.0  0.0  0.0
  0.0  1.0  0.0  0.0
  0.0  0.0  1.0  0.0
  0.0  0.0  0.0  1.0
 ]
 

Overrides:

toString in class Object

Returns:

the string representation (not null, not empty)

hashCode

public int hashCode()

Returns a hash code. If two matrices have identical values, they will have the same hash code. The matrix is unaffected.

Overrides:

hashCode in class Object

Returns:

a 32-bit value for use in hashing

See Also:

• Object.hashCode()

equals

public boolean equals(Object o)

Tests for exact equality with the argument, distinguishing -0 from 0. If o is null, false is returned. Either way, the current instance is unaffected.

Overrides:

equals in class Object

Parameters:

o - the object to compare (may be null, unaffected)

Returns:

true if this and o have identical values, otherwise false

clone

public Matrix4f clone()

Creates a copy. The current instance is unaffected.

Overrides:

clone in class Object

Returns:

a new instance with the same element values