SbMatrix(3IV)

NAME
SbMatrix — 4x4 matrix class

INHERITS FROM
SbMatrix

SYNOPSIS
#include <Inventor/SbLinear.h>

Methods from class SbMatrix:

SbMatrix()

SbMatrix(float a11, float a12, float a13, float a14, float a21, float a22, float a23, float a24, float a31, float a32, float a33, float a34, float a41, float a42, float a43, float a44)

SbMatrix(const SbMat &m)
void
setValue(const SbMat &m)
void
getValue(SbMat &m) const
const SbMat &
getValue() const
void
makeIdentity()
static SbMatrix
identity()
void
setRotate(const SbRotation &q)
void
setScale(float s)
void
setScale(const SbVec3f &s)
void
setTranslate(const SbVec3f &t)
void
setTransform(const SbVec3f &t, const SbRotation &r, const SbVec3f &s)
void
setTransform(const SbVec3f &t, const SbRotation &r, const SbVec3f &s, const SbRotation &so)
void
setTransform(const SbVec3f &translation, const SbRotation &rotation, const SbVec3f &scaleFactor, const SbRotation &scaleOrientation, const SbVec3f &center)
void
getTransform(SbVec3f &t, SbRotation &r, SbVec3f &s, SbRotation &so) const
void
getTransform(SbVec3f &translation, SbRotation &rotation, SbVec3f &scaleFactor, SbRotation &scaleOrientation, const SbVec3f &center) const
float
det3(int r1, int r2, int r3, int c1, int c2, int c3) const
float
det3() const
float
det4() const
SbBool
factor(SbMatrix &r, SbVec3f &s, SbMatrix &u, SbVec3f &t, SbMatrix &proj) const
SbMatrix
inverse() const
SbBool
LUDecomposition(int index[4], float &d)
void
LUBackSubstitution(int index[4], float b[4]) const
SbMatrix
transpose() const
SbMatrix &
multRight(const SbMatrix &m)
SbMatrix &
multLeft(const SbMatrix &m)
void
multMatrixVec(const SbVec3f &src, SbVec3f &dst) const
void
multVecMatrix(const SbVec3f &src, SbVec3f &dst) const
void
multDirMatrix(const SbVec3f &src, SbVec3f &dst) const
void
multLineMatrix(const SbLine &src, SbLine &dst) const
void
print(FILE *fp) const
float *
operator float*()
SbMat
operator SbMat&()
float *
operator [](int i)
const float *
operator [](int i) const
SbMatrix &
operator =(const SbMat &m)
SbMatrix &
operator =(const SbMatrix &m)
SbMatrix &
operator =(const SbRotation &q)
SbMatrix &
operator *=(const SbMatrix &m)
SbMatrix
operator *(const SbMatrix &m1, const SbMatrix &m2)
int
operator ==(const SbMatrix &m1, const SbMatrix &m2)
int
operator !=(const SbMatrix &m1, const SbMatrix &m2)
SbBool
equals(const SbMatrix &m, float tolerance) const

DESCRIPTION
4x4 matrix class/datatype used by many Inventor node and action classes. The matrices are stored in row-major order.

METHODS

SbMatrix()

SbMatrix(float a11, float a12, float a13, float a14, float a21, float a22, float a23, float a24, float a31, float a32, float a33, float a34, float a41, float a42, float a43, float a44)

SbMatrix(const SbMat &m)
Constructors.

void
setValue(const SbMat &m)
Sets value from 4x4 array of elements.

void
getValue(SbMat &m) const
const SbMat &
getValue() const
Returns 4x4 array of elements.

void
makeIdentity()
Sets matrix to be identity.

static SbMatrix
identity()
Returns an identity matrix.

void
setRotate(const SbRotation &q)
Sets matrix to rotate by given rotation.

void
setScale(float s)
Sets matrix to scale by given uniform factor.

void
setScale(const SbVec3f &s)
Sets matrix to scale by given vector.

void
setTranslate(const SbVec3f &t)
Sets matrix to translate by given vector.

void
setTransform(const SbVec3f &t, const SbRotation &r, const SbVec3f &s)
void
setTransform(const SbVec3f &t, const SbRotation &r, const SbVec3f &s, const SbRotation &so)
void
setTransform(const SbVec3f &translation, const SbRotation &rotation, const SbVec3f &scaleFactor, const SbRotation &scaleOrientation, const SbVec3f &center)
Composes the matrix based on a translation, rotation, scale, orientation for scale, and center. The center is the center point for scaling and rotation. The scaleOrientation chooses the primary axes for the scale.

void
getTransform(SbVec3f &t, SbRotation &r, SbVec3f &s, SbRotation &so) const
Return translation, rotation, scale, and scale orientation components of the matrix.

void
getTransform(SbVec3f &translation, SbRotation &rotation, SbVec3f &scaleFactor, SbRotation &scaleOrientation, const SbVec3f &center) const
Decomposes the matrix into a translation, rotation, scale, and scale orientation. Any projection information is discarded. The decomposition depends upon choice of center point for rotation and scaling, which is optional as the last parameter. Note that if the center is 0, decompose() is the same as factor() where t is translation, u is rotation, s is scaleFactor, and r is ScaleOrientation.

float
det3(int r1, int r2, int r3, int c1, int c2, int c3) const
Returns determinant of 3x3 submatrix composed of given row and column indices (0-3 for each).

float
det3() const
Returns determinant of upper-left 3x3 submatrix.

float
det4() const
Returns determinant of entire matrix.

SbBool
factor(SbMatrix &r, SbVec3f &s, SbMatrix &u, SbVec3f &t, SbMatrix &proj) const
Factors a matrix m into 5 pieces: m = r s r^ u t, where r^ means transpose of r, and r and u are rotations, s is a scale, and t is a translation. Any projection information is returned in proj. NOTE: the projection matrix is always set to identity.

SbMatrix
inverse() const
Returns inverse of matrix. Results are undefined for singular matrices. Uses LU decomposition.

SbBool
LUDecomposition(int index[4], float &d)
Perform in-place LU decomposition of matrix. index is index of rows in matrix. d is the parity of row swaps. Returns FALSE if singular.

void
LUBackSubstitution(int index[4], float b[4]) const
Perform back-substitution on LU-decomposed matrix. Index is permutation of rows from original matrix.

SbMatrix
transpose() const
Returns transpose of matrix.

SbMatrix &
multRight(const SbMatrix &m)
SbMatrix &
multLeft(const SbMatrix &m)
Multiplies matrix by given matrix on right or left.

void
multMatrixVec(const SbVec3f &src, SbVec3f &dst) const
Multiplies matrix by given column vector, giving vector result.

void
multVecMatrix(const SbVec3f &src, SbVec3f &dst) const
Multiplies given row vector by matrix, giving vector result.

void
multDirMatrix(const SbVec3f &src, SbVec3f &dst) const
Multiplies given row vector by matrix, giving vector result. src is assumed to be a direction vector, so translation part of matrix is ignored. Note: if you wish to transform surface points and normals by a matrix, call multVecMatrix() for the points and call multDirMatrix() on the inverse transpose of the matrix for the normals.

void
multLineMatrix(const SbLine &src, SbLine &dst) const
Multiplies the given line's origin by the matrix, and the line's direction by the rotation portion of the matrix.

void
print(FILE *fp) const
Prints a formatted version of the matrix to the given file pointer.

float *
operator float*()
Cast: returns pointer to storage of first element.

SbMat
operator SbMat&()
Cast: returns reference to 4x4 array.

float *
operator [](int i)
const float *
operator [](int i) const
Make it look like a usual matrix (so you can do m[3][2]).

SbMatrix &
operator =(const SbMat &m)
Sets value from 4x4 array of elements.

SbMatrix &
operator =(const SbMatrix &m)
Set the matrix from another SbMatrix.

SbMatrix &
operator =(const SbRotation &q)
Set the matrix from an SbRotation.

SbMatrix &
operator *=(const SbMatrix &m)
Performs right multiplication with another matrix.

SbMatrix
operator *(const SbMatrix &m1, const SbMatrix &m2)
Binary multiplication of matrices.

int
operator ==(const SbMatrix &m1, const SbMatrix &m2)
int
operator !=(const SbMatrix &m1, const SbMatrix &m2)
Equality comparison operators.

SbBool
equals(const SbMatrix &m, float tolerance) const
Equality comparison within given tolerance, for each component.

FILE FORMAT/DEFAULTS

SEE ALSO
SbVec3f, SbRotation