\inmodule QtCore More...

#include <qsize.h>

Inheritance diagram for QSizeF:

Collaboration diagram for QSizeF:

Public Member Functions
constexpr	QSizeF () noexcept
	Constructs an invalid size.

constexpr	QSizeF (const QSize &sz) noexcept
	Constructs a size with floating point accuracy from the given size.

constexpr	QSizeF (qreal w, qreal h) noexcept
	Constructs a size with the given finite width and height.

bool	isNull () const noexcept
	Returns `true` if both the width and height are 0.0 (ignoring the sign); otherwise returns `false`.

constexpr bool	isEmpty () const noexcept
	Returns `true` if either of the width and height is less than or equal to 0; otherwise returns `false`.

constexpr bool	isValid () const noexcept
	Returns `true` if both the width and height are equal to or greater than 0; otherwise returns `false`.

constexpr qreal	width () const noexcept
	Returns the width.

constexpr qreal	height () const noexcept
	Returns the height.

constexpr void	setWidth (qreal w) noexcept
	Sets the width to the given finite width.

constexpr void	setHeight (qreal h) noexcept
	Sets the height to the given finite height.

void	transpose () noexcept
	Swaps the width and height values.

constexpr QSizeF	transposed () const noexcept

void	scale (qreal w, qreal h, Qt::AspectRatioMode mode) noexcept
	Scales the size to a rectangle with the given width and height, according to the specified mode.

void	scale (const QSizeF &s, Qt::AspectRatioMode mode) noexcept
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Scales the size to a rectangle with the given size, according to the specified mode.

QSizeF	scaled (qreal w, qreal h, Qt::AspectRatioMode mode) const noexcept

QSizeF	scaled (const QSizeF &s, Qt::AspectRatioMode mode) const noexcept
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

constexpr QSizeF	expandedTo (const QSizeF &) const noexcept
	Returns a size holding the maximum width and height of this size and the given otherSize.

constexpr QSizeF	boundedTo (const QSizeF &) const noexcept
	Returns a size holding the minimum width and height of this size and the given otherSize.

constexpr QSizeF	grownBy (QMarginsF m) const noexcept

constexpr QSizeF	shrunkBy (QMarginsF m) const noexcept

constexpr qreal &	rwidth () noexcept
	Returns a reference to the width.

constexpr qreal &	rheight () noexcept
	Returns a reference to the height.

constexpr QSizeF &	operator+= (const QSizeF &) noexcept
	Adds the given size to this size and returns a reference to this size.

constexpr QSizeF &	operator-= (const QSizeF &) noexcept
	Subtracts the given size from this size and returns a reference to this size.

constexpr QSizeF &	operator*= (qreal c) noexcept
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Multiplies both the width and height by the given finite factor and returns a reference to the size.

QSizeF &	operator/= (qreal c)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Divides both the width and height by the given divisor and returns a reference to the size.

constexpr QSize	toSize () const noexcept
	Returns an integer based copy of this size.

Friends
QT_WARNING_PUSH QT_WARNING_DISABLE_FLOAT_COMPARE friend constexpr bool	qFuzzyCompare (const QSizeF &s1, const QSizeF &s2) noexcept

QT_WARNING_POP friend constexpr bool	qFuzzyIsNull (const QSizeF &size) noexcept

constexpr bool	comparesEqual (const QSizeF &lhs, const QSizeF &rhs) noexcept

constexpr bool	comparesEqual (const QSizeF &lhs, const QSize &rhs) noexcept

constexpr QSizeF	operator+ (const QSizeF &s1, const QSizeF &s2) noexcept
	Returns the sum of s1 and s2; each component is added separately.

constexpr QSizeF	operator- (const QSizeF &s1, const QSizeF &s2) noexcept
	Returns s2 subtracted from s1; each component is subtracted separately.

constexpr QSizeF	operator* (const QSizeF &s, qreal c) noexcept
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Multiplies the given size by the given finite factor and returns the result.

constexpr QSizeF	operator* (qreal c, const QSizeF &s) noexcept
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Multiplies the given size by the given finite factor and returns the result.

QSizeF	operator/ (const QSizeF &s, qreal c)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Divides the given size by the given divisor and returns the result.

template<std::size_t I, typename S , std::enable_if_t<(I< 2), bool > = true, std::enable_if_t< std::is_same_v< q20::remove_cvref_t< S >, QSizeF >, bool > = true>
constexpr decltype(auto)	get (S &&s) noexcept

Related Symbols
(Note that these are not member symbols.)
QDataStream &	operator<< (QDataStream &stream, const QSizeF &size)
	Writes the given size to the given stream and returns a reference to the stream.

QDataStream &	operator>> (QDataStream &stream, QSizeF &size)
	Reads a size from the given stream into the given size and returns a reference to the stream.

Detailed Description

\inmodule QtCore

The QSizeF class defines the size of a two-dimensional object using floating point precision.

A size is specified by a width() and a height(). It can be set in the constructor and changed using the setWidth(), setHeight(), or scale() functions, or using arithmetic operators. A size can also be manipulated directly by retrieving references to the width and height using the rwidth() and rheight() functions. Finally, the width and height can be swapped using the transpose() function.

The isValid() function determines if a size is valid. A valid size has both width and height greater than or equal to zero. The isEmpty() function returns true if either of the width and height is less than (or equal to) zero, while the isNull() function returns true only if both the width and the height is zero.

Use the expandedTo() function to retrieve a size which holds the maximum height and width of this size and a given size. Similarly, the boundedTo() function returns a size which holds the minimum height and width of this size and a given size.

The QSizeF class also provides the toSize() function returning a QSize copy of this size, constructed by rounding the width and height to the nearest integers.

QSizeF objects can be streamed as well as compared.

See also: QSize, QPointF, QRectF

Definition at line 207 of file qsize.h.

Constructor & Destructor Documentation

◆ QSizeF() [1/3]

QSizeF::QSizeF ( )

inlineconstexprnoexcept

Constructs an invalid size.

See also: isValid()

Definition at line 317 of file qsize.h.

◆ QSizeF() [2/3]

QSizeF::QSizeF ( const QSize & size )

inlineconstexprnoexcept

Constructs a size with floating point accuracy from the given size.

See also: toSize(), QSize::toSizeF()

Definition at line 319 of file qsize.h.

◆ QSizeF() [3/3]

QSizeF::QSizeF	(	qreal	w,
		qreal	h )

inlineconstexprnoexcept

Constructs a size with the given finite width and height.

Definition at line 321 of file qsize.h.

Member Function Documentation

◆ boundedTo()

QSizeF QSizeF::boundedTo ( const QSizeF & otherSize ) const

inlinenodiscardconstexprnoexcept

Returns a size holding the minimum width and height of this size and the given otherSize.

See also: expandedTo(), scale()

Definition at line 396 of file qsize.h.

◆ expandedTo()

QSizeF QSizeF::expandedTo ( const QSizeF & otherSize ) const

inlinenodiscardconstexprnoexcept

Returns a size holding the maximum width and height of this size and the given otherSize.

See also: boundedTo(), scale()

Definition at line 391 of file qsize.h.

◆ grownBy()

QSizeF QSizeF::grownBy ( QMarginsF margins ) const

inlinenodiscardconstexprnoexcept

Since: 5.14

Returns the size that results from growing this size by margins.

See also: shrunkBy()

Definition at line 233 of file qsize.h.

◆ height()

qreal QSizeF::height ( ) const

inlineconstexprnoexcept

Returns the height.

See also: width(), setHeight()

Definition at line 335 of file qsize.h.

◆ isEmpty()

bool QSizeF::isEmpty ( ) const

inlineconstexprnoexcept

Returns true if either of the width and height is less than or equal to 0; otherwise returns false.

See also: isNull(), isValid()

Definition at line 326 of file qsize.h.

◆ isNull()

bool QSizeF::isNull ( ) const

inlinenoexcept

Returns true if both the width and height are 0.0 (ignoring the sign); otherwise returns false.

See also: isValid(), isEmpty()

Definition at line 323 of file qsize.h.

◆ isValid()

bool QSizeF::isValid ( ) const

inlineconstexprnoexcept

Returns true if both the width and height are equal to or greater than 0; otherwise returns false.

See also: isNull(), isEmpty()

Definition at line 329 of file qsize.h.

◆ operator*=()

QSizeF & QSizeF::operator*= ( qreal factor )

inlineconstexprnoexcept

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Multiplies both the width and height by the given finite factor and returns a reference to the size.

See also: scale()

Definition at line 376 of file qsize.h.

◆ operator+=()

QSizeF & QSizeF::operator+= ( const QSizeF & size )

inlineconstexprnoexcept

Adds the given size to this size and returns a reference to this size.

For example:

QSizeF s( 3, 7);
QSizeF r(-1, 4);
s += r;
 
// s becomes (2,11)

Definition at line 362 of file qsize.h.

◆ operator-=()

QSizeF & QSizeF::operator-= ( const QSizeF & size )

inlineconstexprnoexcept

Subtracts the given size from this size and returns a reference to this size.

For example:

QSizeF s( 3, 7);
QSizeF r(-1, 4);
s -= r;
 
// s becomes (4,3)

Definition at line 369 of file qsize.h.

◆ operator/=()

QSizeF & QSizeF::operator/= ( qreal divisor )

inline

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Divides both the width and height by the given divisor and returns a reference to the size.

The divisor must not be either zero or NaN.

See also: scale()

Definition at line 383 of file qsize.h.

◆ rheight()

qreal & QSizeF::rheight ( )

inlineconstexprnoexcept

Returns a reference to the height.

Using a reference makes it possible to manipulate the height directly. For example:

QSizeF size(100, 10.2);
size.rheight() += 5.5;
 
// size becomes (100,15.7)

See also: rwidth(), setHeight()

Definition at line 359 of file qsize.h.

◆ rwidth()

qreal & QSizeF::rwidth ( )

inlineconstexprnoexcept

Returns a reference to the width.

Using a reference makes it possible to manipulate the width directly. For example:

QSizeF size(100.3, 10);
size.rwidth() += 20.5;
 
 // size becomes (120.8,10)

See also: rheight(), setWidth()

Definition at line 356 of file qsize.h.

◆ scale() [1/2]

void QSizeF::scale	(	const QSizeF &	s,
		Qt::AspectRatioMode	mode )

inlinenoexcept

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Scales the size to a rectangle with the given size, according to the specified mode.

Definition at line 350 of file qsize.h.

◆ scale() [2/2]

void QSizeF::scale	(	qreal	width,
		qreal	height,
		Qt::AspectRatioMode	mode )

inlinenoexcept

Scales the size to a rectangle with the given width and height, according to the specified mode.

\list

If mode is Qt::IgnoreAspectRatio, the size is set to (width, height).
If mode is Qt::KeepAspectRatio, the current size is scaled to a rectangle as large as possible inside (width, height), preserving the aspect ratio.
If mode is Qt::KeepAspectRatioByExpanding, the current size is scaled to a rectangle as small as possible outside (width, height), preserving the aspect ratio. \endlist

Example:

QSizeF t1(10, 12);
t1.scale(60, 60, Qt::IgnoreAspectRatio);
// t1 is (60, 60)
 
QSizeF t2(10, 12);
t2.scale(60, 60, Qt::KeepAspectRatio);
// t2 is (50, 60)
 
QSizeF t3(10, 12);
t3.scale(60, 60, Qt::KeepAspectRatioByExpanding);
// t3 is (60, 72)

See also: setWidth(), setHeight(), scaled()

Definition at line 347 of file qsize.h.

◆ scaled() [1/2]

QSizeF QSizeF::scaled	(	const QSizeF &	s,
		Qt::AspectRatioMode	mode ) const

nodiscardnoexcept

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

Since: 5.0

Returns a size scaled to a rectangle with the given size s, according to the specified mode.

Definition at line 640 of file qsize.cpp.

◆ scaled() [2/2]

QSizeF QSizeF::scaled	(	qreal	width,
		qreal	height,
		Qt::AspectRatioMode	mode ) const

inlinenodiscardnoexcept

Since: 5.0

Returns a size scaled to a rectangle with the given width and height, according to the specified mode.

See also: scale()

Definition at line 353 of file qsize.h.

◆ setHeight()

void QSizeF::setHeight ( qreal height )

inlineconstexprnoexcept

Sets the height to the given finite height.

See also: height(), rheight(), setWidth()

Definition at line 341 of file qsize.h.

◆ setWidth()

void QSizeF::setWidth ( qreal width )

inlineconstexprnoexcept

Sets the width to the given finite width.

See also: width(), rwidth(), setHeight()

Definition at line 338 of file qsize.h.

◆ shrunkBy()

QSizeF QSizeF::shrunkBy ( QMarginsF margins ) const

inlinenodiscardconstexprnoexcept

Since: 5.14

Returns the size that results from shrinking this size by margins.

See also: grownBy()

Definition at line 235 of file qsize.h.

◆ toSize()

QSize QSizeF::toSize ( ) const

inlineconstexprnoexcept

Returns an integer based copy of this size.

Note that the coordinates in the returned size will be rounded to the nearest integer.

See also: QSizeF(), QSize::toSizeF()

Definition at line 401 of file qsize.h.

◆ transpose()

void QSizeF::transpose ( )

noexcept

Swaps the width and height values.

See also: setWidth(), setHeight(), transposed()

Definition at line 581 of file qsize.cpp.

◆ transposed()

QSizeF QSizeF::transposed ( ) const

inlinenodiscardconstexprnoexcept

Since: 5.0

Returns the size with width and height values swapped.

See also: transpose()

Definition at line 344 of file qsize.h.

◆ width()

qreal QSizeF::width ( ) const

inlineconstexprnoexcept

Returns the width.

See also: height(), setWidth()

Definition at line 332 of file qsize.h.

Friends And Related Symbol Documentation

◆ comparesEqual [1/2]

bool comparesEqual	(	const QSizeF &	lhs,
		const QSize &	rhs )

friend

Definition at line 262 of file qsize.h.

◆ comparesEqual [2/2]

bool comparesEqual	(	const QSizeF &	lhs,
		const QSizeF &	rhs )

friend

Definition at line 259 of file qsize.h.

◆ get

template<std::size_t I, typename S , std::enable_if_t<(I< 2), bool > = true, std::enable_if_t< std::is_same_v< q20::remove_cvref_t< S >, QSizeF >, bool > = true>

decltype(auto) get ( S && s )

friend

Definition at line 292 of file qsize.h.

◆ operator* [1/2]

QSizeF operator*	(	const QSizeF &	size,
		qreal	factor )

friend

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Multiplies the given size by the given finite factor and returns the result.

See also: QSizeF::scale()

Definition at line 269 of file qsize.h.

◆ operator* [2/2]

QSizeF operator*	(	qreal	c,
		const QSizeF &	s )

friend

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Multiplies the given size by the given finite factor and returns the result.

Definition at line 271 of file qsize.h.

◆ operator+

QSizeF operator+	(	const QSizeF &	s1,
		const QSizeF &	s2 )

friend

Returns the sum of s1 and s2; each component is added separately.

Definition at line 265 of file qsize.h.

◆ operator-

QSizeF operator-	(	const QSizeF &	s1,
		const QSizeF &	s2 )

friend

Returns s2 subtracted from s1; each component is subtracted separately.

Definition at line 267 of file qsize.h.

◆ operator/

QSizeF operator/	(	const QSizeF &	size,
		qreal	divisor )

friend

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.Divides the given size by the given divisor and returns the result.

The divisor must not be either zero or NaN.

See also: QSizeF::scale()

Definition at line 273 of file qsize.h.

◆ operator<<()

QDataStream & operator<<	(	QDataStream &	stream,
		const QSizeF &	size )

See also: {Serializing Qt Data Types}

◆ operator>>()

QDataStream & operator>>	(	QDataStream &	stream,
		QSizeF &	size )

See also: {Serializing Qt Data Types}

◆ qFuzzyCompare

QT_WARNING_PUSH QT_WARNING_DISABLE_FLOAT_COMPARE friend constexpr bool qFuzzyCompare	(	const QSizeF &	lhs,
		const QSizeF &	rhs )

friend

Since: 6.8

Returns true if the size lhs is approximately equal to the size rhs; otherwise returns false.

The sizes are considered approximately equal if their width and height are approximately equal.

Definition at line 249 of file qsize.h.

◆ qFuzzyIsNull

QT_WARNING_POP friend constexpr bool qFuzzyIsNull ( const QSizeF & size )

friend

Since: 6.8

Returns true if both width and height of the size size are approximately equal to zero.

Definition at line 257 of file qsize.h.

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

qtbase/src/corelib/tools/qsize.h (3ca9877f8cae41e1b1cb3c72d4a7872d97fb8254)
qtbase/src/corelib/tools/qsize.cpp (3ca9877f8cae41e1b1cb3c72d4a7872d97fb8254)

Public Member Functions

Friends

Related Symbols

Detailed Description

Constructor & Destructor Documentation

◆ QSizeF() [1/3]

◆ QSizeF() [2/3]

◆ QSizeF() [3/3]

Member Function Documentation

◆ boundedTo()

◆ expandedTo()

◆ grownBy()

◆ height()

◆ isEmpty()

◆ isNull()

◆ isValid()

◆ operator*=()

◆ operator+=()

◆ operator-=()

◆ operator/=()

◆ rheight()

◆ rwidth()

◆ scale() [1/2]

◆ scale() [2/2]

◆ scaled() [1/2]

◆ scaled() [2/2]

◆ setHeight()

◆ setWidth()

◆ shrunkBy()

◆ toSize()

◆ transpose()

◆ transposed()

◆ width()

Friends And Related Symbol Documentation

◆ comparesEqual [1/2]

◆ comparesEqual [2/2]

◆ get

◆ operator* [1/2]

◆ operator* [2/2]

◆ operator+

◆ operator-

◆ operator/

◆ operator<<()

◆ operator>>()

◆ qFuzzyCompare

◆ qFuzzyIsNull