QTransform Class Reference

The QTransform class specifies 2D transformations of a coordinate system. More...

#include <qtransform.h>

Public Types
enum	TransformationType {   TxNone = 0x00 , TxTranslate = 0x01 , TxScale = 0x02 , TxRotate = 0x04 ,   TxShear = 0x08 , TxProject = 0x10 }

Public Member Functions
	QTransform (Qt::Initialization)
	QTransform ()
	QTransform (qreal h11, qreal h12, qreal h13, qreal h21, qreal h22, qreal h23, qreal h31, qreal h32, qreal h33)
	QTransform (qreal h11, qreal h12, qreal h21, qreal h22, qreal dx, qreal dy)
QTransform &	operator= (QTransform &&other) noexcept=default
QTransform &	operator= (const QTransform &) noexcept=default
	QTransform (QTransform &&other) noexcept=default
	QTransform (const QTransform &other) noexcept=default
bool	isAffine () const
bool	isIdentity () const
bool	isInvertible () const
bool	isScaling () const
bool	isRotating () const
bool	isTranslating () const
TransformationType	type () const
qreal	determinant () const
qreal	m11 () const
qreal	m12 () const
qreal	m13 () const
qreal	m21 () const
qreal	m22 () const
qreal	m23 () const
qreal	m31 () const
qreal	m32 () const
qreal	m33 () const
qreal	dx () const
qreal	dy () const
void	setMatrix (qreal m11, qreal m12, qreal m13, qreal m21, qreal m22, qreal m23, qreal m31, qreal m32, qreal m33)
QTransform	inverted (bool *invertible=nullptr) const
QTransform	adjoint () const
QTransform	transposed () const
QTransform &	translate (qreal dx, qreal dy)
QTransform &	scale (qreal sx, qreal sy)
QTransform &	shear (qreal sh, qreal sv)
QTransform &	rotate (qreal a, Qt::Axis axis=Qt::ZAxis)
QTransform &	rotateRadians (qreal a, Qt::Axis axis=Qt::ZAxis)
bool	operator== (const QTransform &) const
bool	operator!= (const QTransform &) const
QTransform &	operator*= (const QTransform &)
QTransform	operator* (const QTransform &o) const
	operator QVariant () const
void	reset ()
QPoint	map (const QPoint &p) const
QPointF	map (const QPointF &p) const
QLine	map (const QLine &l) const
QLineF	map (const QLineF &l) const
QPolygonF	map (const QPolygonF &a) const
QPolygon	map (const QPolygon &a) const
QRegion	map (const QRegion &r) const
QPainterPath	map (const QPainterPath &p) const
QPolygon	mapToPolygon (const QRect &r) const
QRect	mapRect (const QRect &) const
QRectF	mapRect (const QRectF &) const
void	map (int x, int y, int *tx, int *ty) const
void	map (qreal x, qreal y, qreal *tx, qreal *ty) const
QTransform &	operator*= (qreal div)
QTransform &	operator/= (qreal div)
QTransform &	operator+= (qreal div)
QTransform &	operator-= (qreal div)
auto	asAffineMatrix ()

Static Public Member Functions
static bool	squareToQuad (const QPolygonF &square, QTransform &result)
static bool	quadToSquare (const QPolygonF &quad, QTransform &result)
static bool	quadToQuad (const QPolygonF &one, const QPolygonF &two, QTransform &result)
static QTransform	fromTranslate (qreal dx, qreal dy)
static QTransform	fromScale (qreal dx, qreal dy)

Friends
Q_GUI_EXPORT QDataStream &	operator>> (QDataStream &s, Affine &m)
Q_GUI_EXPORT QDataStream &	operator<< (QDataStream &s, const Affine &m)

Related Functions
(Note that these are not member functions.)
size_t	qHash (const QTransform &key, size_t seed) noexcept
QDataStream &	operator<< (QDataStream &stream, const QTransform &matrix)
QDataStream &	operator>> (QDataStream &stream, QTransform &matrix)
QPoint	operator* (const QPoint &point, const QTransform &matrix)
QPointF	operator* (const QPointF &point, const QTransform &matrix)
QLineF	operator* (const QLineF &line, const QTransform &matrix)
QLine	operator* (const QLine &line, const QTransform &matrix)
QPolygonF	operator* (const QPolygonF &polygon, const QTransform &matrix)
QPolygon	operator* (const QPolygon &polygon, const QTransform &matrix)
QRegion	operator* (const QRegion &region, const QTransform &matrix)
QPainterPath	operator* (const QPainterPath &path, const QTransform &matrix)
bool	qFuzzyCompare (const QTransform &t1, const QTransform &t2)

Detailed Description

The QTransform class specifies 2D transformations of a coordinate system.

Since

4.3

\inmodule QtGui

A transformation specifies how to translate, scale, shear, rotate or project the coordinate system, and is typically used when rendering graphics.

A QTransform object can be built using the setMatrix(), scale(), rotate(), translate() and shear() functions. Alternatively, it can be built by applying \l {QTransform::Basic Matrix Operations}{basic matrix operations}. The matrix can also be defined when constructed, and it can be reset to the identity matrix (the default) using the reset() function.

The QTransform class supports mapping of graphic primitives: A given point, line, polygon, region, or painter path can be mapped to the coordinate system defined by this matrix using the map() function. In case of a rectangle, its coordinates can be transformed using the mapRect() function. A rectangle can also be transformed into a polygon (mapped to the coordinate system defined by this matrix), using the mapToPolygon() function.

QTransform provides the isIdentity() function which returns true if the matrix is the identity matrix, and the isInvertible() function which returns true if the matrix is non-singular (i.e. AB = BA = I). The inverted() function returns an inverted copy of this matrix if it is invertible (otherwise it returns the identity matrix), and adjoint() returns the matrix's classical adjoint. In addition, QTransform provides the determinant() function which returns the matrix's determinant.

Finally, the QTransform class supports matrix multiplication, addition and subtraction, and objects of the class can be streamed as well as compared.

Definition at line 55 of file qtransform.h.

Member Enumeration Documentation

TransformationType

enum QTransform::TransformationType

\value TxNone \value TxTranslate \value TxScale \value TxRotate \value TxShear \value TxProject

Enumerator
TxNone
TxTranslate
TxScale
TxRotate
TxShear
TxProject

Definition at line 58 of file qtransform.h.

Constructor & Destructor Documentation

QTransform() [1/6]

QTransform::QTransform ( Qt::Initialization  )

inlineexplicit

Definition at line 67 of file qtransform.h.

QTransform() [2/6]

QTransform::QTransform ( )

inline

Constructs an identity matrix.

All elements are set to zero except m11 and m22 (specifying the scale) and m33 which are set to 1.

See also

reset()

Definition at line 68 of file qtransform.h.

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QTransform() [3/6]

QTransform::QTransform ( qreal  m11, qreal  m12, qreal  m13, qreal  m21, qreal  m22, qreal  m23, qreal  m31, qreal  m32, qreal  m33  )

inline

Constructs a matrix with the elements, m11, m12, m13, m21, m22, m23, m31, m32, m33.

See also

setMatrix()

Definition at line 72 of file qtransform.h.

QTransform() [4/6]

QTransform::QTransform ( qreal  m11, qreal  m12, qreal  m21, qreal  m22, qreal  dx, qreal  dy  )

inline

Constructs a matrix with the elements, m11, m12, m21, m22, dx and dy.

See also

setMatrix()

Definition at line 78 of file qtransform.h.

QTransform() [5/6]

QTransform::QTransform ( QTransform &&  other )

defaultnoexcept

QTransform() [6/6]

QTransform::QTransform ( const QTransform &  other )

defaultnoexcept

Member Function Documentation

adjoint()

QTransform QTransform::adjoint

(

)

const

Returns the adjoint of this matrix.

Definition at line 298 of file qtransform.cpp.

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asAffineMatrix()

auto QTransform::asAffineMatrix ( )

inline

Definition at line 169 of file qtransform.h.

determinant()

qreal QTransform::determinant ( ) const

inline

Returns the matrix's determinant.

Definition at line 220 of file qtransform.h.

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dx()

qreal QTransform::dx ( ) const

inline

Returns the horizontal translation factor.

See also

m31(), translate(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 262 of file qtransform.h.

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dy()

qreal QTransform::dy ( ) const

inline

Returns the vertical translation factor.

See also

translate(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 266 of file qtransform.h.

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fromScale()

QTransform QTransform::fromScale ( qreal  sx, qreal  sy  )

static

Creates a matrix which corresponds to a scaling of sx horizontally and sy vertically. This is the same as QTransform().scale(sx, sy) but slightly faster.

Since

4.5

Definition at line 503 of file qtransform.cpp.

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fromTranslate()

QTransform QTransform::fromTranslate ( qreal  dx, qreal  dy  )

static

Creates a matrix which corresponds to a translation of dx along the x axis and dy along the y axis. This is the same as QTransform().translate(dx, dy) but slightly faster.

Since

4.5

Definition at line 437 of file qtransform.cpp.

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inverted()

QTransform QTransform::inverted

(

bool *

invertible = nullptr

)

const

Returns an inverted copy of this matrix.

If the matrix is singular (not invertible), the returned matrix is the identity matrix. If invertible is valid (i.e. not 0), its value is set to true if the matrix is invertible, otherwise it is set to false.

See also

isInvertible()

Definition at line 339 of file qtransform.cpp.

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isAffine()

bool QTransform::isAffine ( ) const

inline

Returns true if the matrix represent an affine transformation, otherwise returns false.

Definition at line 192 of file qtransform.h.

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isIdentity()

bool QTransform::isIdentity ( ) const

inline

Returns true if the matrix is the identity matrix, otherwise returns false.

See also

reset()

Definition at line 196 of file qtransform.h.

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isInvertible()

bool QTransform::isInvertible ( ) const

inline

Returns true if the matrix is invertible, otherwise returns false.

See also

inverted()

Definition at line 201 of file qtransform.h.

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isRotating()

bool QTransform::isRotating ( ) const

inline

Returns true if the matrix represents some kind of a rotating transformation, otherwise returns false.

Note

A rotation transformation of 180 degrees and/or 360 degrees is treated as a scaling transformation.

See also

reset()

Definition at line 210 of file qtransform.h.

isScaling()

bool QTransform::isScaling ( ) const

inline

Returns true if the matrix represents a scaling transformation, otherwise returns false.

See also

reset()

Definition at line 206 of file qtransform.h.

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isTranslating()

bool QTransform::isTranslating ( ) const

inline

Returns true if the matrix represents a translating transformation, otherwise returns false.

See also

reset()

Definition at line 215 of file qtransform.h.

m11()

qreal QTransform::m11 ( ) const

inline

Returns the horizontal scaling factor.

See also

scale(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 226 of file qtransform.h.

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m12()

qreal QTransform::m12 ( ) const

inline

Returns the vertical shearing factor.

See also

shear(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 230 of file qtransform.h.

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m13()

qreal QTransform::m13 ( ) const

inline

Returns the horizontal projection factor.

See also

translate(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 234 of file qtransform.h.

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m21()

qreal QTransform::m21 ( ) const

inline

Returns the horizontal shearing factor.

See also

shear(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 238 of file qtransform.h.

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m22()

qreal QTransform::m22 ( ) const

inline

Returns the vertical scaling factor.

See also

scale(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 242 of file qtransform.h.

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m23()

qreal QTransform::m23 ( ) const

inline

Returns the vertical projection factor.

See also

translate(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 246 of file qtransform.h.

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m31()

qreal QTransform::m31 ( ) const

inline

Returns the horizontal translation factor.

See also

dx(), translate(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 250 of file qtransform.h.

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m32()

qreal QTransform::m32 ( ) const

inline

Returns the vertical translation factor.

See also

dy(), translate(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 254 of file qtransform.h.

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m33()

qreal QTransform::m33 ( ) const

inline

Returns the division factor.

See also

translate(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 258 of file qtransform.h.

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map() [1/10]

QLine QTransform::map

(

const QLine &

l

)

const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Creates and returns a QLineF object that is a copy of the given line, l, mapped into the coordinate system defined by this matrix.

Definition at line 1242 of file qtransform.cpp.

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map() [2/10]

QLineF QTransform::map

(

const QLineF &

line

)

const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Creates and returns a QLine object that is a copy of the given line, mapped into the coordinate system defined by this matrix. Note that the transformed coordinates are rounded to the nearest integer.

Definition at line 1301 of file qtransform.cpp.

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map() [3/10]

QPainterPath QTransform::map

(

const QPainterPath &

path

)

const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Creates and returns a QPainterPath object that is a copy of the given path, mapped into the coordinate system defined by this matrix.

Definition at line 1648 of file qtransform.cpp.

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map() [4/10]

QPoint QTransform::map

(

const QPoint &

point

)

const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Creates and returns a QPoint object that is a copy of the given point, mapped into the coordinate system defined by this matrix. Note that the transformed coordinates are rounded to the nearest integer.

Definition at line 1122 of file qtransform.cpp.

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map() [5/10]

QPointF QTransform::map

(

const QPointF &

p

)

const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Creates and returns a QPointF object that is a copy of the given point, p, mapped into the coordinate system defined by this matrix.

Definition at line 1173 of file qtransform.cpp.

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map() [6/10]

QPolygon QTransform::map

(

const QPolygon &

polygon

)

const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Creates and returns a QPolygon object that is a copy of the given polygon, mapped into the coordinate system defined by this matrix. Note that the transformed coordinates are rounded to the nearest integer.

Definition at line 1428 of file qtransform.cpp.

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map() [7/10]

QPolygonF QTransform::map

(

const QPolygonF &

polygon

)

const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Creates and returns a QPolygonF object that is a copy of the given polygon, mapped into the coordinate system defined by this matrix.

Definition at line 1398 of file qtransform.cpp.

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map() [8/10]

QRegion QTransform::map

(

const QRegion &

region

)

const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Creates and returns a QRegion object that is a copy of the given region, mapped into the coordinate system defined by this matrix.

Calling this method can be rather expensive if rotations or shearing are used.

Definition at line 1473 of file qtransform.cpp.

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map() [9/10]

void QTransform::map	(	int	x,
		int	y,
		int *	tx,
		int *	ty
	)		const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Maps the given coordinates x and y into the coordinate system defined by this matrix. The resulting values are put in *tx and *ty, respectively. Note that the transformed coordinates are rounded to the nearest integer.

Definition at line 2033 of file qtransform.cpp.

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map() [10/10]

void QTransform::map	(	qreal	x,
		qreal	y,
		qreal *	tx,
		qreal *	ty
	)		const

Maps the given coordinates x and y into the coordinate system defined by this matrix. The resulting values are put in *tx and *ty, respectively.

The coordinates are transformed using the following formulas:

The point (x, y) is the original point, and (x', y') is the transformed point.

See also

{QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 2019 of file qtransform.cpp.

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mapRect() [1/2]

QRect QTransform::mapRect

(

const QRect &

rectangle

)

const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Creates and returns a QRect object that is a copy of the given rectangle, mapped into the coordinate system defined by this matrix. Note that the transformed coordinates are rounded to the nearest integer.

Definition at line 1875 of file qtransform.cpp.

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mapRect() [2/2]

QRectF QTransform::mapRect

(

const QRectF &

rectangle

)

const

Creates and returns a QRectF object that is a copy of the given rectangle, mapped into the coordinate system defined by this matrix.

The rectangle's coordinates are transformed using the following formulas:

If rotation or shearing has been specified, this function returns the bounding rectangle. To retrieve the exact region the given rectangle maps to, use the mapToPolygon() function instead.

See also

mapToPolygon(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 1945 of file qtransform.cpp.

mapToPolygon()

QPolygon QTransform::mapToPolygon

(

const QRect &

rectangle

)

const

Creates and returns a QPolygon representation of the given rectangle, mapped into the coordinate system defined by this matrix.

The rectangle's coordinates are transformed using the following formulas:

Polygons and rectangles behave slightly differently when transformed (due to integer rounding), so {matrix.map(QPolygon(rectangle))} is not always the same as {matrix.mapToPolygon(rectangle)}.

See also

mapRect(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 1693 of file qtransform.cpp.

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operator QVariant()

QTransform::operator QVariant

(

)

const

Returns the transform as a QVariant.

Definition at line 2102 of file qtransform.cpp.

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operator!=()

bool QTransform::operator!=

(

const QTransform &

matrix

)

const

Returns true if this matrix is not equal to the given matrix, otherwise returns false.

Definition at line 799 of file qtransform.cpp.

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operator*()

QTransform QTransform::operator*

(

const QTransform &

matrix

)

const

Returns the result of multiplying this matrix by the given matrix.

Note that matrix multiplication is not commutative, i.e. a*b != b*a.

Definition at line 896 of file qtransform.cpp.

operator*=() [1/2]

QTransform & QTransform::operator*=

(

const QTransform &

matrix

)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Returns the result of multiplying this matrix by the given matrix.

Definition at line 811 of file qtransform.cpp.

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operator*=() [2/2]

QT_WARNING_PUSH QT_WARNING_DISABLE_FLOAT_COMPARE QTransform & QTransform::operator*= ( qreal  scalar )

inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Returns the result of performing an element-wise multiplication of this matrix with the given scalar.

Definition at line 274 of file qtransform.h.

operator+=()

QTransform & QTransform::operator+= ( qreal  scalar )

inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Returns the matrix obtained by adding the given scalar to each element of this matrix.

Definition at line 298 of file qtransform.h.

operator-=()

QTransform & QTransform::operator-= ( qreal  scalar )

inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Returns the matrix obtained by subtracting the given scalar from each element of this matrix.

Definition at line 314 of file qtransform.h.

operator/=()

QTransform & QTransform::operator/= ( qreal  scalar )

inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Returns the result of performing an element-wise division of this matrix by the given scalar.

Definition at line 291 of file qtransform.h.

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operator=() [1/2]

QTransform & QTransform::operator= ( const QTransform &  matrix )

defaultnoexcept

Assigns the given matrix's values to this matrix.

operator=() [2/2]

QTransform& QTransform::operator= ( QTransform &&  other )

defaultnoexcept

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operator==()

bool QTransform::operator==

(

const QTransform &

matrix

)

const

Returns true if this matrix is equal to the given matrix, otherwise returns false.

Definition at line 758 of file qtransform.cpp.

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quadToQuad()

bool QTransform::quadToQuad ( const QPolygonF &  one, const QPolygonF &  two, QTransform &  trans  )

static

Creates a transformation matrix, trans, that maps a four-sided polygon, one, to another four-sided polygon, two. Returns true if the transformation is possible; otherwise returns false.

This is a convenience method combining quadToSquare() and squareToQuad() methods. It allows the input quad to be transformed into any other quad.

See also

squareToQuad(), quadToSquare()

Definition at line 1831 of file qtransform.cpp.

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quadToSquare()

bool QTransform::quadToSquare ( const QPolygonF &  quad, QTransform &  trans  )

static

Creates a transformation matrix, trans, that maps a four-sided polygon, quad, to a unit square. Returns true if the transformation is constructed or false if such a transformation does not exist.

See also

squareToQuad(), quadToQuad()

Definition at line 1808 of file qtransform.cpp.

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reset()

void QTransform::reset

(

)

Resets the matrix to an identity matrix, i.e. all elements are set to zero, except m11 and m22 (specifying the scale) and m33 which are set to 1.

See also

QTransform(), isIdentity(), {QTransform::Basic Matrix Operations}{Basic Matrix Operations}

Definition at line 1018 of file qtransform.cpp.

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rotate()

QTransform & QTransform::rotate	(	qreal	angle,
		Qt::Axis	axis = Qt::ZAxis
	)

Rotates the coordinate system counterclockwise by the given angle about the specified axis and returns a reference to the matrix.

Note that if you apply a QTransform to a point defined in widget coordinates, the direction of the rotation will be clockwise because the y-axis points downwards.

The angle is specified in degrees.

See also

setMatrix()

Definition at line 588 of file qtransform.cpp.

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rotateRadians()

QTransform & QTransform::rotateRadians	(	qreal	angle,
		Qt::Axis	axis = Qt::ZAxis
	)

Rotates the coordinate system counterclockwise by the given angle about the specified axis and returns a reference to the matrix.

Note that if you apply a QTransform to a point defined in widget coordinates, the direction of the rotation will be clockwise because the y-axis points downwards.

The angle is specified in radians.

See also

setMatrix()

Definition at line 685 of file qtransform.cpp.

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scale()

QTransform & QTransform::scale	(	qreal	sx,
		qreal	sy
	)

Scales the coordinate system by sx horizontally and sy vertically, and returns a reference to the matrix.

See also

setMatrix()

Definition at line 460 of file qtransform.cpp.

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setMatrix()

void QTransform::setMatrix	(	qreal	m11,
		qreal	m12,
		qreal	m13,
		qreal	m21,
		qreal	m22,
		qreal	m23,
		qreal	m31,
		qreal	m32,
		qreal	m33
	)

Sets the matrix elements to the specified values, m11, m12, m13 m21, m22, m23 m31, m32 and m33. Note that this function replaces the previous values. QTransform provides the translate(), rotate(), scale() and shear() convenience functions to manipulate the various matrix elements based on the currently defined coordinate system.

See also

QTransform()

Definition at line 1856 of file qtransform.cpp.

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shear()

QTransform & QTransform::shear	(	qreal	sh,
		qreal	sv
	)

Shears the coordinate system by sh horizontally and sv vertically, and returns a reference to the matrix.

See also

setMatrix()

Definition at line 526 of file qtransform.cpp.

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squareToQuad()

bool QTransform::squareToQuad ( const QPolygonF &  quad, QTransform &  trans  )

static

Creates a transformation matrix, trans, that maps a unit square to a four-sided polygon, quad. Returns true if the transformation is constructed or false if such a transformation does not exist.

See also

quadToSquare(), quadToQuad()

Definition at line 1743 of file qtransform.cpp.

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translate()

QTransform & QTransform::translate	(	qreal	dx,
		qreal	dy
	)

Moves the coordinate system dx along the x axis and dy along the y axis, and returns a reference to the matrix.

See also

setMatrix()

Definition at line 392 of file qtransform.cpp.

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transposed()

QTransform QTransform::transposed

(

)

const

Returns the transpose of this matrix.

Definition at line 321 of file qtransform.cpp.

type()

QTransform::TransformationType QTransform::type

(

)

const

Returns the transformation type of this matrix.

The transformation type is the highest enumeration value capturing all of the matrix's transformations. For example, if the matrix both scales and shears, the type would be TxShear, because TxShear has a higher enumeration value than TxScale.

Knowing the transformation type of a matrix is useful for optimization: you can often handle specific types more optimally than handling the generic case.

Definition at line 2054 of file qtransform.cpp.

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Friends And Related Function Documentation

operator*() [1/8]

QLine operator* ( const QLine &  line, const QTransform &  matrix  )

related

This is the same as {matrix}.map({line}).

See also

QTransform::map()

Definition at line 365 of file qtransform.h.

operator*() [2/8]

QLineF operator* ( const QLineF &  line, const QTransform &  matrix  )

related

This is the same as {matrix}.map({line}).

See also

QTransform::map()

Definition at line 363 of file qtransform.h.

operator*() [3/8]

QPainterPath operator* ( const QPainterPath &  path, const QTransform &  matrix  )

related

Since

4.3

This is the same as {matrix}.map({path}).

See also

QTransform::map()

Definition at line 336 of file qpainterpath.h.

operator*() [4/8]

QPoint operator* ( const QPoint &  point, const QTransform &  matrix  )

related

This is the same as {matrix}.map({point}).

See also

QTransform::map()

Definition at line 359 of file qtransform.h.

operator*() [5/8]

QPointF operator* ( const QPointF &  point, const QTransform &  matrix  )

related

Same as {matrix}.map({point}).

See also

QTransform::map()

Definition at line 361 of file qtransform.h.

operator*() [6/8]

QPolygon operator* ( const QPolygon &  polygon, const QTransform &  matrix  )

related

This is the same as {matrix}.map({polygon}).

See also

QTransform::map()

Definition at line 367 of file qtransform.h.

operator*() [7/8]

QPolygonF operator* ( const QPolygonF &  polygon, const QTransform &  matrix  )

related

Since

4.3

This is the same as {matrix}.map({polygon}).

See also

QTransform::map()

Definition at line 369 of file qtransform.h.

operator*() [8/8]

QRegion operator* ( const QRegion &  region, const QTransform &  matrix  )

related

This is the same as {matrix}.map({region}).

See also

QTransform::map()

Definition at line 371 of file qtransform.h.

operator<< [1/2]

Q_GUI_EXPORT QDataStream& operator<< ( QDataStream &  s, const Affine &  m  )

friend

Definition at line 2350 of file qtransform.cpp.

operator<<() [2/2]

QDataStream & operator<< ( QDataStream &  stream, const QTransform &  matrix  )

related

Since

4.3

Writes the given matrix to the given stream and returns a reference to the stream.

See also

{Serializing Qt Data Types}

Definition at line 1034 of file qtransform.cpp.

operator>> [1/2]

Q_GUI_EXPORT QDataStream& operator>> ( QDataStream &  s, QTransform::Affine &  m  )

friend

Definition at line 2324 of file qtransform.cpp.

operator>>() [2/2]

QDataStream & operator>> ( QDataStream &  stream, QTransform &  matrix  )

related

Since

4.3

Reads the given matrix from the given stream and returns a reference to the stream.

See also

{Serializing Qt Data Types}

Definition at line 1058 of file qtransform.cpp.

qFuzzyCompare()

bool qFuzzyCompare ( const QTransform &  t1, const QTransform &  t2  )

related

Since

4.6

Returns true if t1 and t2 are equal, allowing for a small fuzziness factor for floating-point comparisons; false otherwise.

Definition at line 333 of file qtransform.h.

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qHash()

size_t qHash ( const QTransform &  key, size_t  seed  )

related

Since

5.6

Returns the hash value for key, using seed to seed the calculation.

Definition at line 778 of file qtransform.cpp.

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

• src/gui/painting/qtransform.h
• src/gui/painting/qtransform.cpp