Class Matrix4

java.lang.Object

com.codename1.gpu.Matrix4

public final class Matrix4
extends Object

Portable column-major 4x4 float matrix math used by the 3D API. Every operation works on plain float[16] arrays so it behaves identically on every platform without relying on native transform support. The layout matches OpenGL/Metal column-major convention: element m[c * 4 + r] is column c, row r.

Method Summary

Modifier and Type	Method	Description
static void	copy(float[] src, float[] dst)	Copies the contents of src into dst.
static float[]	identity()	Allocates a new identity matrix.
static boolean	invert(float[] m, float[] dst)	Inverts m into dst.
static float[]	lookAt(float eyeX, float eyeY, float eyeZ, float centerX, float centerY, float centerZ, float upX, float upY, float upZ)	Builds a right-handed look-at view matrix from eye, target and up vectors.
static void	multiply(float[] a, float[] b, float[] dst)	Multiplies a * b and stores the result in dst.
static float[]	normalMatrix(float[] m)	Computes the transpose of the upper-left 3x3 of the inverse of m, expanded to a 4x4.
static float[]	ortho(float left, float right, float bottom, float top, float near, float far)	Builds an orthographic projection matrix.
static float[]	perspective(float fovYRadians, float aspect, float near, float far)	Builds a perspective projection matrix.
static float[]	rotation(float angleRadians, float x, float y, float z)	Returns a rotation matrix around an arbitrary axis.
static float[]	scaling(float x, float y, float z)	Returns a scale matrix.
static void	setIdentity(float[] m)	Resets the supplied matrix to the identity matrix.
static float[]	translation(float x, float y, float z)	Returns a translation matrix.

Methods inherited from class Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

identity

public static float[] identity()

Allocates a new identity matrix.

setIdentity

public static void setIdentity(float[] m)

Resets the supplied matrix to the identity matrix.

copy

public static void copy(float[] src,
 float[] dst)

Copies the contents of src into dst. Both arrays must hold 16 floats.

multiply

public static void multiply(float[] a,
 float[] b,
 float[] dst)

Multiplies a * b and stores the result in dst. dst may not alias a or b.

perspective

public static float[] perspective(float fovYRadians,
 float aspect,
 float near,
 float far)

Builds a perspective projection matrix. fovYRadians is the vertical field of view in radians, aspect the width/height ratio.

ortho

public static float[] ortho(float left,
 float right,
 float bottom,
 float top,
 float near,
 float far)

Builds an orthographic projection matrix.

lookAt

public static float[] lookAt(float eyeX,
 float eyeY,
 float eyeZ,
 float centerX,
 float centerY,
 float centerZ,
 float upX,
 float upY,
 float upZ)

Builds a right-handed look-at view matrix from eye, target and up vectors.

translation

public static float[] translation(float x,
 float y,
 float z)

Returns a translation matrix.

scaling

public static float[] scaling(float x,
 float y,
 float z)

Returns a scale matrix.

rotation

public static float[] rotation(float angleRadians,
 float x,
 float y,
 float z)

Returns a rotation matrix around an arbitrary axis. angleRadians is the rotation angle, (x, y, z) the rotation axis (need not be normalized).

normalMatrix

public static float[] normalMatrix(float[] m)

Computes the transpose of the upper-left 3x3 of the inverse of m, expanded to a 4x4. This is the correct matrix for transforming normals. Returns the identity when m is not invertible.

invert

public static boolean invert(float[] m,
 float[] dst)

Inverts m into dst. Returns false (leaving dst untouched) when the matrix is singular.