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LMatrix4d Class Reference

This is a 4-by-4 transform matrix. More...

#include "lmatrix.h"

List of all members.

Classes

class  CRow
class  Row

Public Types

typedef const double * const_iterator
typedef const double * iterator

Public Member Functions

 LMatrix4d (const LMatrix4d &other)
 LMatrix4d (double e00, double e01, double e02, double e03, double e10, double e11, double e12, double e13, double e20, double e21, double e22, double e23, double e30, double e31, double e32, double e33)
 LMatrix4d (const LMatrix3d &upper3)
 LMatrix4d (const LMatrix3d &upper3, const LVecBase3d &trans)
size_t add_hash (size_t hash) const
 Adds the vector into the running hash.
size_t add_hash (size_t hash, double threshold) const
 Adds the vector into the running hash.
bool almost_equal (const LMatrix4d &other, double threshold) const
 Returns true if two matrices are memberwise equal within a specified tolerance.
bool almost_equal (const LMatrix4d &other) const
 Returns true if two matrices are memberwise equal within a default tolerance based on the numeric type.
iterator begin ()
 Returns an iterator that may be used to traverse the elements of the matrix, STL-style.
const_iterator begin () const
 Returns an iterator that may be used to traverse the elements of the matrix, STL-style.
int compare_to (const LMatrix4d &other) const
 This flavor of compare_to uses a default threshold value based on the numeric type.
int compare_to (const LMatrix4d &other, double threshold) const
 Sorts matrices lexicographically, componentwise.
iterator end ()
 Returns an iterator that may be used to traverse the elements of the matrix, STL-style.
const_iterator end () const
 Returns an iterator that may be used to traverse the elements of the matrix, STL-style.
void fill (double fill_value)
 Sets each element of the matrix to the indicated fill_value.
void generate_hash (ChecksumHashGenerator &hashgen) const
 Adds the vector to the indicated hash generator.
void generate_hash (ChecksumHashGenerator &hashgen, double scale) const
 Adds the vector to the indicated hash generator.
double get_cell (int row, int col) const
 Returns a particular element of the matrix.
LVecBase4d get_col (int col) const
 Retrieves the indicated column of the matrix as a 4-component vector.
LVecBase3d get_col3 (int col) const
 Retrieves the indicated column of the matrix as a 3-component vector, ignoring the last row.
const double * get_data () const
 Returns the address of the first of the nine data elements in the matrix.
size_t get_hash () const
 Returns a suitable hash for phash_map.
size_t get_hash (double threshold) const
 Returns a suitable hash for phash_map.
int get_num_components () const
 Returns the number of elements in the matrix, 16.
LVecBase4d get_row (int row) const
 Retrieves the indicated row of the matrix as a 4-component vector.
void get_row (LVecBase4d &result_vec, int row) const
void get_row3 (LVecBase3d &result_vec, int row) const
LVecBase3d get_row3 (int row) const
 Retrieves the row column of the matrix as a 3-component vector, ignoring the last column.
LMatrix3d get_upper_3 () const
 Retrieves the upper 3x3 submatrix.
bool invert_affine_from (const LMatrix4d &other)
 Performs an invert of the indicated matrix, storing the result in this matrix.
bool invert_from (const LMatrix4d &other)
 Computes the inverse of the other matrix, and stores the result in this matrix.
bool invert_in_place ()
 Inverts the current matrix.
bool is_nan () const
 Returns true if any component of the matrix is not-a-number, false otherwise.
 MAKE_SEQ (get_rows, size, get_row)
 MAKE_SEQ (get_cols, size, get_col)
 MAKE_SEQ (get_row3s, size, get_row3)
void multiply (const LMatrix4d &other1, const LMatrix4d &other2)
bool operator!= (const LMatrix4d &other) const
double & operator() (int row, int col)
double operator() (int row, int col) const
LMatrix4d operator* (double scalar) const
LMatrix4d operator* (const LMatrix4d &other) const
LMatrix4doperator*= (const LMatrix4d &other)
LMatrix4doperator*= (double scalar)
LMatrix4doperator+= (const LMatrix4d &other)
 Performs a memberwise addition between two matrices.
LMatrix4doperator-= (const LMatrix4d &other)
 Performs a memberwise addition between two matrices.
LMatrix4d operator/ (double scalar) const
LMatrix4doperator/= (double scalar)
bool operator< (const LMatrix4d &other) const
 This performs a lexicographical comparison.
LMatrix4doperator= (double fill_value)
LMatrix4doperator= (const LMatrix4d &other)
bool operator== (const LMatrix4d &other) const
Row operator[] (int i)
CRow operator[] (int i) const
void output (ostream &out) const
void read_datagram (DatagramIterator &scan)
 Reads itself out of the datagram.
void set (double e00, double e01, double e02, double e03, double e10, double e11, double e12, double e13, double e20, double e21, double e22, double e23, double e30, double e31, double e32, double e33)
void set_cell (int row, int col, double value)
 Changes a particular element of the matrix.
void set_col (int col, const LVecBase4d &v)
 Replaces the indicated column of the matrix.
void set_col (int col, const LVecBase3d &v)
 Replaces the indicated column of the matrix with the indicated 3-component vector, ignoring the last row.
void set_rotate_mat (double angle, const LVecBase3d &axis, CoordinateSystem cs=CS_default)
 Sets mat to a matrix that rotates by the given angle in degrees counterclockwise about the indicated vector.
void set_rotate_mat_normaxis (double angle, const LVecBase3d &axis, CoordinateSystem cs=CS_default)
 Fills mat with a matrix that rotates by the given angle in degrees counterclockwise about the indicated vector.
void set_row (int row, const LVecBase3d &v)
 Replaces the indicated row of the matrix with the indicated 3-component vector, ignoring the last column.
void set_row (int row, const LVecBase4d &v)
 Replaces the indicated row of the matrix.
void set_scale_mat (const LVecBase3d &scale)
 Fills mat with a matrix that applies the indicated scale in each of the three axes.
void set_scale_shear_mat (const LVecBase3d &scale, const LVecBase3d &shear, CoordinateSystem cs=CS_default)
 Fills mat with a matrix that applies the indicated scale and shear.
void set_shear_mat (const LVecBase3d &shear, CoordinateSystem cs=CS_default)
 Fills mat with a matrix that applies the indicated shear in each of the three planes.
void set_translate_mat (const LVecBase3d &trans)
 Fills mat with a matrix that applies the indicated translation.
void set_upper_3 (const LMatrix3d &upper3)
 Sets the upper 3x3 submatrix.
void transpose_from (const LMatrix4d &other)
void transpose_in_place ()
void write (ostream &out, int indent_level=0) const
void write_datagram (Datagram &destination) const
 Writes the matrix to the datagram.
LVecBase4d xform (const LVecBase4d &v) const
 4-component vector or point times matrix.
LVecBase3d xform_point (const LVecBase3d &v) const
 The matrix transforms a 3-component point (including translation component) and returns the result.
LVecBase3d xform_vec (const LVecBase3d &v) const
 The matrix transforms a 3-component vector (without translation component) and returns the result.
LVecBase3d xform_vec_general (const LVecBase3d &v) const
 The matrix transforms a 3-component vector (without translation component) and returns the result, as a fully general operation.

Static Public Member Functions

static const LMatrix4dconvert_mat (CoordinateSystem from, CoordinateSystem to)
 Returns a matrix that transforms from the indicated coordinate system to the indicated coordinate system.
static TypeHandle get_class_type ()
static const LMatrix4dident_mat ()
 Returns an identity matrix.
static void init_type ()
static const LMatrix4dones_mat ()
 Returns an matrix filled with ones.
static LMatrix4d rotate_mat (double angle, const LVecBase3d &axis, CoordinateSystem cs=CS_default)
 Returns a matrix that rotates by the given angle in degrees counterclockwise about the indicated vector.
static LMatrix4d rotate_mat_normaxis (double angle, const LVecBase3d &axis, CoordinateSystem cs=CS_default)
 Returns a matrix that rotates by the given angle in degrees counterclockwise about the indicated vector.
static LMatrix4d scale_mat (const LVecBase3d &scale)
 Returns a matrix that applies the indicated scale in each of the three axes.
static LMatrix4d scale_mat (double sx, double sy, double sz)
 Returns a matrix that applies the indicated scale in each of the three axes.
static LMatrix4d scale_mat (double scale)
 Returns a matrix that applies the indicated uniform scale.
static LMatrix4d scale_shear_mat (const LVecBase3d &scale, const LVecBase3d &shear, CoordinateSystem cs=CS_default)
 Returns a matrix that applies the indicated scale and shear.
static LMatrix4d scale_shear_mat (double sx, double sy, double sz, double shxy, double shxz, double shyz, CoordinateSystem cs=CS_default)
 Returns a matrix that applies the indicated scale and shear.
static LMatrix4d shear_mat (double shxy, double shxz, double shyz, CoordinateSystem cs=CS_default)
 Returns a matrix that applies the indicated shear in each of the three planes.
static LMatrix4d shear_mat (const LVecBase3d &shear, CoordinateSystem cs=CS_default)
 Returns a matrix that applies the indicated shear in each of the three planes.
static int size ()
 Returns 4: the number of rows of a LMatrix4.
static LMatrix4d translate_mat (double tx, double ty, double tz)
 Returns a matrix that applies the indicated translation.
static LMatrix4d translate_mat (const LVecBase3d &trans)
 Returns a matrix that applies the indicated translation.
static const LMatrix4dy_to_z_up_mat ()
 Returns a matrix that transforms from the Y-up coordinate system to the Z-up coordinate system.
static const LMatrix4dz_to_y_up_mat ()
 Returns a matrix that transforms from the Y-up coordinate system to the Z-up coordinate system.
static const LMatrix4dzeros_mat ()
 Returns an matrix filled with zeros.

Public Attributes

union {
   double   data [4 *4]
   struct {
      double   _00
      double   _01
      double   _02
      double   _03
      double   _10
      double   _11
      double   _12
      double   _13
      double   _20
      double   _21
      double   _22
      double   _23
      double   _30
      double   _31
      double   _32
      double   _33
   }   m
_m

Detailed Description

This is a 4-by-4 transform matrix.

Definition at line 3992 of file lmatrix.h.


Member Function Documentation

size_t LMatrix4d::add_hash ( size_t  hash) const [inline]

Adds the vector into the running hash.

Definition at line 4979 of file lmatrix.h.

size_t LMatrix4d::add_hash ( size_t  hash,
double  threshold 
) const [inline]

Adds the vector into the running hash.

Definition at line 4989 of file lmatrix.h.

bool LMatrix4d::almost_equal ( const LMatrix4d other,
double  threshold 
) const
bool LMatrix4d::almost_equal ( const LMatrix4d other) const [inline]

Returns true if two matrices are memberwise equal within a default tolerance based on the numeric type.

Definition at line 5749 of file lmatrix.h.

LMatrix4d::iterator LMatrix4d::begin ( ) [inline]

Returns an iterator that may be used to traverse the elements of the matrix, STL-style.

Definition at line 4871 of file lmatrix.h.

LMatrix4d::const_iterator LMatrix4d::begin ( ) const [inline]

Returns an iterator that may be used to traverse the elements of the matrix, STL-style.

Definition at line 4893 of file lmatrix.h.

int LMatrix4d::compare_to ( const LMatrix4d other) const [inline]

This flavor of compare_to uses a default threshold value based on the numeric type.

Definition at line 4949 of file lmatrix.h.

Referenced by EggTexture::sorts_less_than().

int LMatrix4d::compare_to ( const LMatrix4d other,
double  threshold 
) const

Sorts matrices lexicographically, componentwise.

Returns a number less than 0 if this matrix sorts before the other one, greater than zero if it sorts after, 0 if they are equivalent (within the indicated tolerance).

Definition at line 1906 of file lmatrix.cxx.

const LMatrix4d & LMatrix4d::convert_mat ( CoordinateSystem  from,
CoordinateSystem  to 
) [static]

Returns a matrix that transforms from the indicated coordinate system to the indicated coordinate system.

Definition at line 1838 of file lmatrix.cxx.

Referenced by EggData::set_coordinate_system().

LMatrix4d::const_iterator LMatrix4d::end ( ) const [inline]

Returns an iterator that may be used to traverse the elements of the matrix, STL-style.

Definition at line 4904 of file lmatrix.h.

LMatrix4d::iterator LMatrix4d::end ( ) [inline]

Returns an iterator that may be used to traverse the elements of the matrix, STL-style.

Definition at line 4882 of file lmatrix.h.

void LMatrix4d::fill ( double  fill_value) [inline]

Sets each element of the matrix to the indicated fill_value.

This is of questionable value, but is sometimes useful when initializing to zero.

Definition at line 4551 of file lmatrix.h.

void LMatrix4d::generate_hash ( ChecksumHashGenerator hashgen) const [inline]

Adds the vector to the indicated hash generator.

Definition at line 5759 of file lmatrix.h.

void LMatrix4d::generate_hash ( ChecksumHashGenerator hashgen,
double  scale 
) const

Adds the vector to the indicated hash generator.

Definition at line 2179 of file lmatrix.cxx.

double LMatrix4d::get_cell ( int  row,
int  col 
) const [inline]

Returns a particular element of the matrix.

Definition at line 4826 of file lmatrix.h.

LVecBase4d LMatrix4d::get_col ( int  col) const [inline]

Retrieves the indicated column of the matrix as a 4-component vector.

Definition at line 4710 of file lmatrix.h.

LVecBase3d LMatrix4d::get_col3 ( int  col) const [inline]

Retrieves the indicated column of the matrix as a 3-component vector, ignoring the last row.

Definition at line 4744 of file lmatrix.h.

const double * LMatrix4d::get_data ( ) const [inline]

Returns the address of the first of the nine data elements in the matrix.

The remaining elements occupy the next eight positions in row-major order.

Definition at line 4850 of file lmatrix.h.

Referenced by XFileDataObject::set().

size_t LMatrix4d::get_hash ( ) const [inline]

Returns a suitable hash for phash_map.

Definition at line 4959 of file lmatrix.h.

size_t LMatrix4d::get_hash ( double  threshold) const [inline]

Returns a suitable hash for phash_map.

Definition at line 4969 of file lmatrix.h.

int LMatrix4d::get_num_components ( ) const [inline]

Returns the number of elements in the matrix, 16.

Definition at line 4860 of file lmatrix.h.

LVecBase4d LMatrix4d::get_row ( int  row) const [inline]

Retrieves the indicated row of the matrix as a 4-component vector.

Definition at line 4688 of file lmatrix.h.

LVecBase3d LMatrix4d::get_row3 ( int  row) const [inline]

Retrieves the row column of the matrix as a 3-component vector, ignoring the last column.

Definition at line 4724 of file lmatrix.h.

Referenced by EggVertexPool::transform().

LMatrix3d LMatrix4d::get_upper_3 ( ) const [inline]

Retrieves the upper 3x3 submatrix.

Definition at line 4619 of file lmatrix.h.

const LMatrix4d & LMatrix4d::ident_mat ( ) [inline, static]
bool LMatrix4d::invert_affine_from ( const LMatrix4d other) [inline]

Performs an invert of the indicated matrix, storing the result in this matrix.

The calculation is only correct of the other matrix represents an affine transform.

The other matrix must be a different object than this matrix. However, if you need to invert a matrix in place, see invert_in_place.

The return value is true if the matrix was successfully inverted, false if the was a singularity.

Definition at line 5451 of file lmatrix.h.

bool LMatrix4d::invert_from ( const LMatrix4d other) [inline]

Computes the inverse of the other matrix, and stores the result in this matrix.

This is a fully general operation and makes no assumptions about the type of transform represented by the matrix.

The other matrix must be a different object than this matrix. However, if you need to invert a matrix in place, see invert_in_place.

The return value is true if the matrix was successfully inverted, false if the was a singularity.

Definition at line 5400 of file lmatrix.h.

Referenced by EggGroup::adjust_under(), and DXFFile::compute_ocs().

bool LMatrix4d::invert_in_place ( ) [inline]

Inverts the current matrix.

Returns true if the inverse is successful, false if the matrix was singular.

Definition at line 5490 of file lmatrix.h.

Referenced by EggTopstrip::adjust_transform(), and EggJointData::get_net_frame_inv().

bool LMatrix4d::is_nan ( ) const [inline]

Returns true if any component of the matrix is not-a-number, false otherwise.

Definition at line 4811 of file lmatrix.h.

const LMatrix4d & LMatrix4d::ones_mat ( ) [inline, static]

Returns an matrix filled with ones.

Definition at line 4390 of file lmatrix.h.

LMatrix4d & LMatrix4d::operator+= ( const LMatrix4d other) [inline]

Performs a memberwise addition between two matrices.

Definition at line 5201 of file lmatrix.h.

LMatrix4d & LMatrix4d::operator-= ( const LMatrix4d other) [inline]

Performs a memberwise addition between two matrices.

Definition at line 5232 of file lmatrix.h.

bool LMatrix4d::operator< ( const LMatrix4d other) const [inline]

This performs a lexicographical comparison.

It's of questionable mathematical meaning, but sometimes has a practical purpose for sorting unique vectors, especially in an STL container. Also see compare_to().

Definition at line 4918 of file lmatrix.h.

void LMatrix4d::read_datagram ( DatagramIterator scan)

Reads itself out of the datagram.

Definition at line 2321 of file lmatrix.cxx.

LMatrix4d LMatrix4d::rotate_mat ( double  angle,
const LVecBase3d axis,
CoordinateSystem  cs = CS_default 
) [inline, static]

Returns a matrix that rotates by the given angle in degrees counterclockwise about the indicated vector.

Definition at line 5595 of file lmatrix.h.

Referenced by EggTransform::add_rotate3d(), EggBase::ns_dispatch_rotate_axis(), and EggBase::ns_dispatch_rotate_xyz().

LMatrix4d LMatrix4d::rotate_mat_normaxis ( double  angle,
const LVecBase3d axis,
CoordinateSystem  cs = CS_default 
) [inline, static]

Returns a matrix that rotates by the given angle in degrees counterclockwise about the indicated vector.

Assumes axis has been prenormalized.

Definition at line 5610 of file lmatrix.h.

Referenced by EggTransform::add_rotate2d(), EggTransform::add_rotx(), EggTransform::add_roty(), EggTransform::add_rotz(), and EggXfmSAnim::compose_with_order().

LMatrix4d LMatrix4d::scale_mat ( const LVecBase3d scale) [inline, static]
LMatrix4d LMatrix4d::scale_mat ( double  scale) [inline, static]

Returns a matrix that applies the indicated uniform scale.

Definition at line 5655 of file lmatrix.h.

LMatrix4d LMatrix4d::scale_mat ( double  sx,
double  sy,
double  sz 
) [inline, static]

Returns a matrix that applies the indicated scale in each of the three axes.

Definition at line 5641 of file lmatrix.h.

LMatrix4d LMatrix4d::scale_shear_mat ( const LVecBase3d scale,
const LVecBase3d shear,
CoordinateSystem  cs = CS_default 
) [inline, static]

Returns a matrix that applies the indicated scale and shear.

Definition at line 5696 of file lmatrix.h.

Referenced by EggXfmSAnim::compose_with_order().

LMatrix4d LMatrix4d::scale_shear_mat ( double  sx,
double  sy,
double  sz,
double  shxy,
double  shxz,
double  shyz,
CoordinateSystem  cs = CS_default 
) [inline, static]

Returns a matrix that applies the indicated scale and shear.

Definition at line 5711 of file lmatrix.h.

void LMatrix4d::set_cell ( int  row,
int  col,
double  value 
) [inline]

Changes a particular element of the matrix.

Definition at line 4837 of file lmatrix.h.

void LMatrix4d::set_col ( int  col,
const LVecBase4d v 
) [inline]

Replaces the indicated column of the matrix.

Definition at line 4646 of file lmatrix.h.

void LMatrix4d::set_col ( int  col,
const LVecBase3d v 
) [inline]

Replaces the indicated column of the matrix with the indicated 3-component vector, ignoring the last row.

Definition at line 4675 of file lmatrix.h.

void LMatrix4d::set_rotate_mat ( double  angle,
const LVecBase3d axis,
CoordinateSystem  cs = CS_default 
)

Sets mat to a matrix that rotates by the given angle in degrees counterclockwise about the indicated vector.

Definition at line 1926 of file lmatrix.cxx.

void LMatrix4d::set_rotate_mat_normaxis ( double  angle,
const LVecBase3d axis,
CoordinateSystem  cs = CS_default 
)

Fills mat with a matrix that rotates by the given angle in degrees counterclockwise about the indicated vector.

Assumes axis has been prenormalized.

Definition at line 1997 of file lmatrix.cxx.

void LMatrix4d::set_row ( int  row,
const LVecBase3d v 
) [inline]

Replaces the indicated row of the matrix with the indicated 3-component vector, ignoring the last column.

Definition at line 4661 of file lmatrix.h.

void LMatrix4d::set_row ( int  row,
const LVecBase4d v 
) [inline]
void LMatrix4d::set_scale_mat ( const LVecBase3d scale) [inline]

Fills mat with a matrix that applies the indicated scale in each of the three axes.

Definition at line 5517 of file lmatrix.h.

void LMatrix4d::set_scale_shear_mat ( const LVecBase3d scale,
const LVecBase3d shear,
CoordinateSystem  cs = CS_default 
) [inline]

Fills mat with a matrix that applies the indicated scale and shear.

Definition at line 5543 of file lmatrix.h.

void LMatrix4d::set_shear_mat ( const LVecBase3d shear,
CoordinateSystem  cs = CS_default 
) [inline]

Fills mat with a matrix that applies the indicated shear in each of the three planes.

Definition at line 5531 of file lmatrix.h.

void LMatrix4d::set_translate_mat ( const LVecBase3d trans) [inline]

Fills mat with a matrix that applies the indicated translation.

Definition at line 5503 of file lmatrix.h.

void LMatrix4d::set_upper_3 ( const LMatrix3d upper3) [inline]

Sets the upper 3x3 submatrix.

Definition at line 4598 of file lmatrix.h.

LMatrix4d LMatrix4d::shear_mat ( double  shxy,
double  shxz,
double  shyz,
CoordinateSystem  cs = CS_default 
) [inline, static]

Returns a matrix that applies the indicated shear in each of the three planes.

Definition at line 5682 of file lmatrix.h.

LMatrix4d LMatrix4d::shear_mat ( const LVecBase3d shear,
CoordinateSystem  cs = CS_default 
) [inline, static]

Returns a matrix that applies the indicated shear in each of the three planes.

Definition at line 5669 of file lmatrix.h.

int LMatrix4d::size ( ) [inline, static]

Returns 4: the number of rows of a LMatrix4.

Definition at line 4800 of file lmatrix.h.

LMatrix4d LMatrix4d::translate_mat ( double  tx,
double  ty,
double  tz 
) [inline, static]

Returns a matrix that applies the indicated translation.

Definition at line 5581 of file lmatrix.h.

LMatrix4d LMatrix4d::translate_mat ( const LVecBase3d trans) [inline, static]
void LMatrix4d::write_datagram ( Datagram destination) const

Writes the matrix to the datagram.

Definition at line 2307 of file lmatrix.cxx.

LVecBase4d LMatrix4d::xform ( const LVecBase4d v) const [inline]

4-component vector or point times matrix.

This is a fully general operation.

Definition at line 5029 of file lmatrix.h.

LVecBase3d LMatrix4d::xform_point ( const LVecBase3d v) const [inline]

The matrix transforms a 3-component point (including translation component) and returns the result.

This assumes the matrix is an affine transform.

Definition at line 5045 of file lmatrix.h.

Referenced by PerlinNoise3::noise(), and ImageTransformColors::process_image().

LVecBase3d LMatrix4d::xform_vec ( const LVecBase3d v) const [inline]

The matrix transforms a 3-component vector (without translation component) and returns the result.

This assumes the matrix is an orthonormal transform.

Definition at line 5066 of file lmatrix.h.

LVecBase3d LMatrix4d::xform_vec_general ( const LVecBase3d v) const [inline]

The matrix transforms a 3-component vector (without translation component) and returns the result, as a fully general operation.

Definition at line 5087 of file lmatrix.h.

const LMatrix4d & LMatrix4d::y_to_z_up_mat ( ) [inline, static]

Returns a matrix that transforms from the Y-up coordinate system to the Z-up coordinate system.

Definition at line 5727 of file lmatrix.h.

const LMatrix4d & LMatrix4d::z_to_y_up_mat ( ) [inline, static]

Returns a matrix that transforms from the Y-up coordinate system to the Z-up coordinate system.

Definition at line 5738 of file lmatrix.h.

const LMatrix4d & LMatrix4d::zeros_mat ( ) [inline, static]

Returns an matrix filled with zeros.

Definition at line 4400 of file lmatrix.h.


The documentation for this class was generated from the following files:
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