org.instantreality.InstantIO
Class Matrix4f

java.lang.Object
  org.instantreality.InstantIO.Matrix4f

public class Matrix4f
extends java.lang.Object

Helper class for exchanging 4x4 matrices of float values.

Matrix4f is a basic helper class for exchanging matrices of 4x4 float values between different software components. It does not contain any means for matrix arithmetics, only methods for setting and getting the matrix elements. It is not meant to be used directly by software components for matrix representation. Instead, software components should use their own, appropriate classes for handling matrices. Only when sending matrices to an OutSlot, or when receiving matrices from an InSlot, the internal representation of matrices should be converted to Matrix4f's. This ensures the interoperability between different software components that use different internal representations for matrixes.

Author:

Helmut Seibert

Field Summary

static Matrix4f

IDENTITY The identity matrix.

Constructor Summary

Matrix4f(float[] matrix)
Creates a new Matrix4f object that gets initialized by a given 16 element float array representing a 4x4 matrix.

Matrix4f(float m11, float m12, float m13, float m14, float m21, float m22, float m23, float m24, float m31, float m32, float m33, float m34, float m41, float m42, float m43, float m44)
Creates a new Matrix4f object that gets initialized by given 16 float values representing a 4x4 matrix.

Matrix4f(Matrix4f matrix)
Constructor that initializes the components of the Matrix4f object with the elements taken from another Matrix4f object.

Method Summary

boolean	equals(java.lang.Object obj) Compares the matrix to another object.
void	get(float[] matrix) Returns the matrix elements.
float	get(int index) Returns one element of the matrix.
java.lang.String	toString() Converts the matrix to a string.
static Matrix4f	valueOf(java.lang.String str) Converts a string to a Matrix4f object.

Methods inherited from class java.lang.Object

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

Field Detail

IDENTITY

public static final Matrix4f IDENTITY

The identity matrix.

Constructor Detail

Matrix4f

public Matrix4f(float m11,
                float m12,
                float m13,
                float m14,
                float m21,
                float m22,
                float m23,
                float m24,
                float m31,
                float m32,
                float m33,
                float m34,
                float m41,
                float m42,
                float m43,
                float m44)

Creates a new Matrix4f object that gets initialized by given 16 float values representing a 4x4 matrix.

Parameters:

m11 - The value at row 1, column 1 of the matrix

m12 - The value at row 1, column 2 of the matrix

m13 - The value at row 1, column 3 of the matrix

m14 - The value at row 1, column 4 of the matrix

m21 - The value at row 2, column 1 of the matrix

m22 - The value at row 2, column 2 of the matrix

m23 - The value at row 2, column 3 of the matrix

m24 - The value at row 2, column 4 of the matrix

m31 - The value at row 3, column 1 of the matrix

m32 - The value at row 3, column 2 of the matrix

m33 - The value at row 3, column 3 of the matrix

m34 - The value at row 3, column 4 of the matrix

m41 - The value at row 4, column 1 of the matrix

m42 - The value at row 4, column 2 of the matrix

m43 - The value at row 4, column 3 of the matrix

m44 - The value at row 4, column 4 of the matrix

Matrix4f

public Matrix4f(float[] matrix)

Creates a new Matrix4f object that gets initialized by a given 16 element float array representing a 4x4 matrix.

Parameters:

matrix - The sixteen components of the matrix

Matrix4f

public Matrix4f(Matrix4f matrix)

Constructor that initializes the components of the Matrix4f object with the elements taken from another Matrix4f object.

The following example demonstrates how to create a Matrix4f object that is an exact copy of another Matrix4f object:

 Matrix4f given_mat = ...;
 Matrix4f mat = new Matrix4f(given_mat);
 

Parameters:

matrix - The other matrix used to initialize the new matrix.

Method Detail

get

public final void get(float[] matrix)

Returns the matrix elements.

The following example extracts the translation vector from the matrix and prints it to the console:

 Matrix4f mat = ...;
 float[] m = new float[16];
 mat.get(m);
 float x = m[12];
 float y = m[13];
 float z = m[14];
 System.out.println("Translation = " + x + " " + y + " " + z);
 

Parameters:

matrix - A float array that gets filled with the elements of the matrix. This array must have at least 16 elements.

get

public final float get(int index)

Returns one element of the matrix.

The following example extracts the translation vector from the matrix and prints it to the console:

 Matrix4f mat = ...;
 float x = mat.get(12);
 float y = mat.get(13);
 float z = mat.get(14);
 System.out.println("Translation = " + x + " " + y + " " + z);
 

Parameters:

index - The index of the element. This must be between 0 and 15, inclusively.

Returns:

The value of the element.

equals

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

Compares the matrix to another object. The result is true if the object is not null and is a Matrix4f object and the matrix elements of the other Matrix4f object are the same as the matrix elements of this matrix.

The following example compares two matrices and prints the result to the console:

 Matrix4f mat1 = ...;
 Matrix4f mat2 = ...;
 System.out.println("Matrices are the same: " + mat1.equals(mat2));
 

Overrides:

equals in class java.lang.Object

Parameters:

obj - the object to compare the matrix to

Returns:

true when the matrices are equal, false otherwise

toString

public final java.lang.String toString()

Converts the matrix to a string. The string representation consists of the 16 matrix elements, separated by space characters.

The following example prints the string representation of a Matrix4f object to the console:

 Matrix4f mat = ...;
 System.out.println("Matrix = " + mat.toString());
 

Overrides:

toString in class java.lang.Object

Returns:

A string representation of the matrix.

valueOf

public static final Matrix4f valueOf(java.lang.String str)

Converts a string to a Matrix4f object. The string must consist of the 16 matrix elements, separated by space characters.

The following example creates a new Matrix4f object that represents a translation of 1 unit along the x axis, 2 units along the y axis, and 3 units along the z axis:

 Matrix4f mat = Matrix4f.valueOf("1.0 0.0 0.0 0.0 0.0 1.0 0.0 0.0 0.0 0.0 1.0 0.0 1.0 2.0 3.0 1.0");
 

Parameters:

str - The string representation of the matrix.

Returns:

The new Matrix4f object, parsed from the string.