QtCore.QRect Class Reference

The QRect class defines a rectangle in the plane using integer precision. More...

Inheritance diagram for QtCore.QRect:

Collaboration diagram for QtCore.QRect:

Public Member Functions
override bool	Equals (object o)
override int	GetHashCode ()
	QRect ()
	QRect (QRect copy)
	QRect (QPoint topleft, QPoint bottomright)
	QRect (QPoint topleft, QSize size)
	QRect (int left, int top, int width, int height)
virtual void	CreateProxy ()
new void	Adjust (int x1, int y1, int x2, int y2)
new QRect	Adjusted (int x1, int y1, int x2, int y2)
new QPoint	Center ()
new bool	Contains (QPoint p, bool proper=false)
new bool	Contains (QRect r, bool proper=false)
new bool	Contains (int x, int y)
new bool	Contains (int x, int y, bool proper)
new void	GetCoords (ref int x1, ref int y1, ref int x2, ref int y2)
new void	GetRect (ref int x, ref int y, ref int w, ref int h)
new QRect	Intersect (QRect r)
new QRect	Intersected (QRect other)
new bool	Intersects (QRect r)
new bool	IsEmpty ()
new bool	IsNull ()
new bool	IsValid ()
new void	MoveBottom (int pos)
new void	MoveBottomLeft (QPoint p)
new void	MoveBottomRight (QPoint p)
new void	MoveCenter (QPoint p)
new void	MoveLeft (int pos)
new void	MoveRight (int pos)
new void	MoveTo (QPoint p)
new void	MoveTo (int x, int t)
new void	MoveTop (int pos)
new void	MoveTopLeft (QPoint p)
new void	MoveTopRight (QPoint p)
new QRect	Normalized ()
new void	SetCoords (int x1, int y1, int x2, int y2)
new void	SetRect (int x, int y, int w, int h)
new void	Translate (QPoint p)
new void	Translate (int dx, int dy)
new QRect	Translated (QPoint p)
new QRect	Translated (int dx, int dy)
new QRect	Unite (QRect r)
new QRect	United (QRect other)
new void	Dispose ()

Static Public Member Functions
static bool	operator!= (QRect arg1, QRect arg2)
static bool	operator== (QRect arg1, QRect arg2)
static QRect	operator& (QRect arg1, QRect arg2)
static QRect	operator| (QRect arg1, QRect arg2)

Protected Member Functions
	QRect (System.Type dummy)

Protected Attributes
SmokeInvocation	interceptor

Properties
new int	Bottom [get, set]
new QPoint	BottomLeft [get, set]
new QPoint	BottomRight [get, set]
new int	Height [get, set]
new int	Left [get, set]
new int	Right [get, set]
new QSize	Size [get, set]
new int	Top [get, set]
new QPoint	TopLeft [get, set]
new QPoint	TopRight [get, set]
new int	Width [get, set]
new int	X [get, set]
new int	Y [get, set]
virtual System.IntPtr	SmokeObject [get, set]

Detailed Description

The QRect class defines a rectangle in the plane using integer precision.

A rectangle is normally expressed as an upper-left corner and a size. The size (width and height) of a QRect is always equivalent to the mathematical rectangle that forms the basis for its rendering.

A QRect can be constructed with a set of left, top, width and height integers, or from a QPoint and a QSize. The following code creates two identical rectangles.

QRect r1(100, 200, 11, 16);

QRect r2(QPoint(100, 200), QSize(11, 16));

There is a third constructor that creates a QRect using the top-left and bottom-right coordinates, but we recommend that you avoid using it. The rationale is that for historical reasons the values returned by the bottom() and right() functions deviate from the true bottom-right corner of the rectangle.

The QRect class provides a collection of functions that return the various rectangle coordinates, and enable manipulation of these. QRect also provide functions to move the rectangle relative to the various coordinates. In addition there is a moveTo() function that moves the rectangle, leaving its top left corner at the given coordinates. Alternatively, the translate() function moves the rectangle the given offset relative to the current position, and the translated() function returns a translated copy of this rectangle.

The size() function returns the rectange's dimensions as a QSize. The dimensions can also be retrieved separately using the width() and height() functions. To manipulate the dimensions use the setSize(), setWidth() or setHeight() functions. Alternatively, the size can be changed by applying either of the functions setting the rectangle coordinates, for example, setBottom() or setRight().

The contains() function tells whether a given point is inside the rectangle or not, and the intersects() function returns true if this rectangle intersects with a given rectangle. The QRect class also provides the intersected() function which returns the intersection rectangle, and the united() function which returns the rectangle that encloses the given rectangle and this:

intersected() united()

The isEmpty() function returns true if left() > right() or top() > bottom(). Note that an empty rectangle is not valid: The isValid() function returns true if left() <= right() and top() <= bottom(). A null rectangle (isNull() == true) on the other hand, has both width and height set to 0.

Note that due to the way QRect and QRectF are defined, an empty QRect is defined in essentially the same way as QRectF.

Finally, QRect objects can be streamed as well as compared.

Rendering

When using an anti-aliased painter, the boundary line of a QRect will be rendered symmetrically on both sides of the mathematical rectangle's boundary line. But when using an aliased painter (the default) other rules apply.

Then, when rendering with a one pixel wide pen the QRect's boundary line will be rendered to the right and below the mathematical rectangle's boundary line.

When rendering with a two pixels wide pen the boundary line will be split in the middle by the mathematical rectangle. This will be the case whenever the pen is set to an even number of pixels, while rendering with a pen with an odd number of pixels, the spare pixel will be rendered to the right and below the mathematical rectangle as in the one pixel case.

Logical representation One pixel wide pen

Two pixel wide pen Three pixel wide pen

Coordinates

The QRect class provides a collection of functions that return the various rectangle coordinates, and enable manipulation of these. QRect also provide functions to move the rectangle relative to the various coordinates.

For example the left(), setLeft() and moveLeft() functions as an example: left() returns the x-coordinate of the rectangle's left edge, setLeft() sets the left edge of the rectangle to the given x coordinate (it may change the width, but will never change the rectangle's right edge) and moveLeft() moves the entire rectangle horizontally, leaving the rectangle's left edge at the given x coordinate and its size unchanged.

Note that for historical reasons the values returned by the bottom() and right() functions deviate from the true bottom-right corner of the rectangle: The right() function returns left() + width() - 1 and the bottom() function returns top() + height() - 1. The same is the case for the point returned by the bottomRight() convenience function. In addition, the x and y coordinate of the topRight() and bottomLeft() functions, respectively, contain the same deviation from the true right and bottom edges.

We recommend that you use x() + width() and y() + height() to find the true bottom-right corner, and avoid right() and bottom(). Another solution is to use QRectF: The QRectF class defines a rectangle in the plane using floating point accuracy for coordinates, and the QRectF::right() and QRectF::bottom() functions do return the right and bottom coordinates.

It is also possible to add offsets to this rectangle's coordinates using the adjust() function, as well as retrieve a new rectangle based on adjustments of the original one using the adjusted() function. If either of the width and height is negative, use the normalized() function to retrieve a rectangle where the corners are swapped.

In addition, QRect provides the getCoords() function which extracts the position of the rectangle's top-left and bottom-right corner, and the getRect() function which extracts the rectangle's top-left corner, width and height. Use the setCoords() and setRect() function to manipulate the rectangle's coordinates and dimensions in one go.

See also QRectF and QRegion.

Constructor & Destructor Documentation

QtCore.QRect.QRect ( System.Type  dummy )

protected

QtCore.QRect.QRect

(

)

Constructs a null rectangle.

See also isNull().

QtCore.QRect.QRect

(

QRect

copy

)

Constructs a null rectangle.

See also isNull().

QtCore.QRect.QRect	(	QPoint	topleft,
		QPoint	bottomright
	)

Constructs a rectangle with the given topLeft and bottomRight corners.

See also setTopLeft() and setBottomRight().

QtCore.QRect.QRect	(	QPoint	topleft,
		QSize	size
	)

Constructs a rectangle with the given topLeft corner and the given size.

See also setTopLeft() and setSize().

QtCore.QRect.QRect	(	int	left,
		int	top,
		int	width,
		int	height
	)

Constructs a rectangle with (x, y) as its top-left corner and the given width and height.

See also setRect().

Member Function Documentation

new void QtCore.QRect.Adjust	(	int	x1,
		int	y1,
		int	x2,
		int	y2
	)

Adds dx1, dy1, dx2 and dy2 respectively to the existing coordinates of the rectangle.

See also adjusted() and setRect().

new QRect QtCore.QRect.Adjusted	(	int	x1,
		int	y1,
		int	x2,
		int	y2
	)

Returns a new rectangle with dx1, dy1, dx2 and dy2 added respectively to the existing coordinates of this rectangle.

See also adjust().

new QPoint QtCore.QRect.Center

(

)

Returns the center point of the rectangle.

See also moveCenter().

new bool QtCore.QRect.Contains	(	QPoint	p,
		bool	proper = false
	)

Returns true if the given point is inside or on the edge of the rectangle, otherwise returns false. If proper is true, this function only returns true if the given point is inside the rectangle (i.e., not on the edge).

See also intersects().

new bool QtCore.QRect.Contains	(	QRect	r,
		bool	proper = false
	)

This is an overloaded function.

Returns true if the given rectangle is inside this rectangle. otherwise returns false. If proper is true, this function only returns true if the rectangle is entirely inside this rectangle (not on the edge).

new bool QtCore.QRect.Contains	(	int	x,
		int	y
	)

This is an overloaded function.

Returns true if the point (x, y) is inside this rectangle, otherwise returns false.

new bool QtCore.QRect.Contains	(	int	x,
		int	y,
		bool	proper
	)

This is an overloaded function.

Returns true if the point (x, y) is inside or on the edge of the rectangle, otherwise returns false. If proper is true, this function only returns true if the point is entirely inside the rectangle(not on the edge).

virtual void QtCore.QRect.CreateProxy ( )

virtual

new void QtCore.QRect.Dispose

(

)

override bool QtCore.QRect.Equals

(

object

o

)

new void QtCore.QRect.GetCoords	(	ref int	x1,
		ref int	y1,
		ref int	x2,
		ref int	y2
	)

Extracts the position of the rectangle's top-left corner to *x1 and *y1, and the position of the bottom-right corner to *x2 and *y2.

See also setCoords() and getRect().

override int QtCore.QRect.GetHashCode

(

)

new void QtCore.QRect.GetRect	(	ref int	x,
		ref int	y,
		ref int	w,
		ref int	h
	)

Extracts the position of the rectangle's top-left corner to *x and *y, and its dimensions to *width and *height.

See also setRect() and getCoords().

new QRect QtCore.QRect.Intersect

(

QRect

r

)

Use intersected(rectangle) instead.

new QRect QtCore.QRect.Intersected

(

QRect

other

)

Returns the intersection of this rectangle and the given rectangle. Note that r.intersected(s) is equivalent to r & s.

This function was introduced in Qt 4.2.

See also intersects(), united(), and operator&=().

new bool QtCore.QRect.Intersects

(

QRect

r

)

Returns true if this rectangle intersects with the given rectangle (i.e., there is at least one pixel that is within both rectangles), otherwise returns false.

The intersection rectangle can be retrieved using the intersected() function.

See also contains().

new bool QtCore.QRect.IsEmpty

(

)

Returns true if the rectangle is empty, otherwise returns false.

An empty rectangle has a left() > right() or top() > bottom(). An empty rectangle is not valid (i.e., isEmpty() == !isValid()).

Use the normalized() function to retrieve a rectangle where the corners are swapped.

See also isNull(), isValid(), and normalized().

new bool QtCore.QRect.IsNull

(

)

Returns true if the rectangle is a null rectangle, otherwise returns false.

A null rectangle has both the width and the height set to 0 (i.e., right() == left() - 1 and bottom() == top() - 1). A null rectangle is also empty, and hence is not valid.

See also isEmpty() and isValid().

new bool QtCore.QRect.IsValid

(

)

Returns true if the rectangle is valid, otherwise returns false.

A valid rectangle has a left() < right() and top() < bottom(). Note that non-trivial operations like intersections are not defined for invalid rectangles. A valid rectangle is not empty (i.e., isValid() == !isEmpty()).

See also isNull(), isEmpty(), and normalized().

new void QtCore.QRect.MoveBottom

(

int

pos

)

Moves the rectangle vertically, leaving the rectangle's bottom edge at the given y coordinate. The rectangle's size is unchanged.

See also bottom(), setBottom(), and moveTop().

new void QtCore.QRect.MoveBottomLeft

(

QPoint

p

)

Moves the rectangle, leaving the bottom-left corner at the given position. The rectangle's size is unchanged.

See also setBottomLeft(), moveBottom(), and moveLeft().

new void QtCore.QRect.MoveBottomRight

(

QPoint

p

)

Moves the rectangle, leaving the bottom-right corner at the given position. The rectangle's size is unchanged.

See also setBottomRight(), moveRight(), and moveBottom().

new void QtCore.QRect.MoveCenter

(

QPoint

p

)

Moves the rectangle, leaving the center point at the given position. The rectangle's size is unchanged.

See also center().

new void QtCore.QRect.MoveLeft

(

int

pos

)

Moves the rectangle horizontally, leaving the rectangle's left edge at the given x coordinate. The rectangle's size is unchanged.

See also left(), setLeft(), and moveRight().

new void QtCore.QRect.MoveRight

(

int

pos

)

Moves the rectangle horizontally, leaving the rectangle's right edge at the given x coordinate. The rectangle's size is unchanged.

See also right(), setRight(), and moveLeft().

new void QtCore.QRect.MoveTo

(

QPoint

p

)

Moves the rectangle, leaving the top-left corner at the given position.

new void QtCore.QRect.MoveTo	(	int	x,
		int	t
	)

Moves the rectangle, leaving the top-left corner at the given position (x, y). The rectangle's size is unchanged.

See also translate() and moveTopLeft().

new void QtCore.QRect.MoveTop

(

int

pos

)

Moves the rectangle vertically, leaving the rectangle's top edge at the given y coordinate. The rectangle's size is unchanged.

See also top(), setTop(), and moveBottom().

new void QtCore.QRect.MoveTopLeft

(

QPoint

p

)

Moves the rectangle, leaving the top-left corner at the given position. The rectangle's size is unchanged.

See also setTopLeft(), moveTop(), and moveLeft().

new void QtCore.QRect.MoveTopRight

(

QPoint

p

)

Moves the rectangle, leaving the top-right corner at the given position. The rectangle's size is unchanged.

See also setTopRight(), moveTop(), and moveRight().

new QRect QtCore.QRect.Normalized

(

)

Returns a normalized rectangle; i.e., a rectangle that has a non-negative width and height.

If width() < 0 the function swaps the left and right corners, and it swaps the top and bottom corners if height() < 0.

See also isValid() and isEmpty().

static bool QtCore.QRect.operator!= ( QRect  arg1, QRect  arg2  )

static

static QRect QtCore.QRect.operator& ( QRect  arg1, QRect  arg2  )

static

Returns the intersection of this rectangle and the given rectangle. Returns an empty rectangle if there is no intersection.

See also operator&=() and intersected().

static bool QtCore.QRect.operator== ( QRect  arg1, QRect  arg2  )

static

static QRect QtCore.QRect.operator| ( QRect  arg1, QRect  arg2  )

static

Returns the bounding rectangle of this rectangle and the given rectangle.

See also operator|=() and united().

new void QtCore.QRect.SetCoords	(	int	x1,
		int	y1,
		int	x2,
		int	y2
	)

Sets the coordinates of the rectangle's top-left corner to (x1, y1), and the coordinates of its bottom-right corner to (x2, y2).

See also coords(), getCoords(), and setRect().

new void QtCore.QRect.SetRect	(	int	x,
		int	y,
		int	w,
		int	h
	)

Sets the coordinates of the rectangle's top-left corner to (x, y), and its size to the given width and height.

See also rect(), getRect(), and setCoords().

new void QtCore.QRect.Translate

(

QPoint

p

)

This is an overloaded function.

Moves the rectangle offset.x() along the x axis and offset.y() along the y axis, relative to the current position.

new void QtCore.QRect.Translate	(	int	dx,
		int	dy
	)

Moves the rectangle dx along the x axis and dy along the y axis, relative to the current position. Positive values move the rectangle to the right and down.

See also moveTopLeft(), moveTo(), and translated().

new QRect QtCore.QRect.Translated

(

QPoint

p

)

This is an overloaded function.

Returns a copy of the rectangle that is translated offset.x() along the x axis and offset.y() along the y axis, relative to the current position.

new QRect QtCore.QRect.Translated	(	int	dx,
		int	dy
	)

Returns a copy of the rectangle that is translated dx along the x axis and dy along the y axis, relative to the current position. Positive values move the rectangle to the right and down.

See also translate().

new QRect QtCore.QRect.Unite

(

QRect

r

)

Use united(rectangle) instead.

new QRect QtCore.QRect.United

(

QRect

other

)

Returns the bounding rectangle of this rectangle and the given rectangle.

This function was introduced in Qt 4.2.

See also intersected().

Member Data Documentation

SmokeInvocation QtCore.QRect.interceptor

protected

Property Documentation

new int QtCore.QRect.Bottom

getset

Returns the y-coordinate of the rectangle's bottom edge.

Note that for historical reasons this function returns top() + height() - 1; use y() + height() to retrieve the true y-coordinate.

Sets the bottom edge of the rectangle to the given y coordinate. May change the height, but will never change the top edge of the rectangle.

new QPoint QtCore.QRect.BottomLeft

getset

Returns the position of the rectangle's bottom-left corner. Note that for historical reasons this function returns QPoint(left(), top() + height() - 1).

Set the bottom-left corner of the rectangle to the given position. May change the size, but will never change the top-right corner of the rectangle.

new QPoint QtCore.QRect.BottomRight

getset

Returns the position of the rectangle's bottom-right corner.

Note that for historical reasons this function returns QPoint(left() + width() -1, top() + height() - 1).

Set the bottom-right corner of the rectangle to the given position. May change the size, but will never change the top-left corner of the rectangle.

new int QtCore.QRect.Height

getset

Returns the height of the rectangle.

Sets the height of the rectangle to the given height. The bottom edge is changed, but not the top one.

new int QtCore.QRect.Left

getset

Returns the x-coordinate of the rectangle's left edge. Equivalent to x().

Sets the left edge of the rectangle to the given x coordinate. May change the width, but will never change the right edge of the rectangle.

Equivalent to setX().

new int QtCore.QRect.Right

getset

Returns the x-coordinate of the rectangle's right edge.

Note that for historical reasons this function returns left() + width() - 1; use x() + width() to retrieve the true x-coordinate.

Sets the right edge of the rectangle to the given x coordinate. May change the width, but will never change the left edge of the rectangle.

new QSize QtCore.QRect.Size

getset

Returns the size of the rectangle.

Sets the size of the rectangle to the given size. The top-left corner is not moved.

virtual System.IntPtr QtCore.QRect.SmokeObject

getset

new int QtCore.QRect.Top

getset

Returns the y-coordinate of the rectangle's top edge. Equivalent to y().

Sets the top edge of the rectangle to the given y coordinate. May change the height, but will never change the bottom edge of the rectangle.

Equivalent to setY().

new QPoint QtCore.QRect.TopLeft

getset

Returns the position of the rectangle's top-left corner.

Set the top-left corner of the rectangle to the given position. May change the size, but will never change the bottom-right corner of the rectangle.

new QPoint QtCore.QRect.TopRight

getset

Returns the position of the rectangle's top-right corner.

Note that for historical reasons this function returns QPoint(left() + width() -1, top()).

Set the top-right corner of the rectangle to the given position. May change the size, but will never change the bottom-left corner of the rectangle.

new int QtCore.QRect.Width

getset

Returns the width of the rectangle.

Sets the width of the rectangle to the given width. The right edge is changed, but not the left one.

new int QtCore.QRect.X

getset

Returns the x-coordinate of the rectangle's left edge. Equivalent to left().

Sets the left edge of the rectangle to the given x coordinate. May change the width, but will never change the right edge of the rectangle.

Equivalent to setLeft().

new int QtCore.QRect.Y

getset

Returns the y-coordinate of the rectangle's top edge. Equivalent to top().

Sets the top edge of the rectangle to the given y coordinate. May change the height, but will never change the bottom edge of the rectangle.

Equivalent to setTop().