class QRect

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

Synopsis

Methods

Static functions

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

A rectangle is normally expressed as a top-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.

r1 = QRect(100, 200, 11, 16)
r2 = QRect(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 provides 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 rectangle’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:

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.

qrect-diagram-zero3

qrect-diagram-one4

Logical representation

One pixel wide pen

qrect-diagram-two5

qrect-diagram-three6

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 provides 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.

../../_images/qrect-coordinates.png

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 right() and 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.

Constraints

QRect is limited to the minimum and maximum values for the int type. Operations on a QRect that could potentially result in values outside this range will result in undefined behavior.

See also

QRectF QRegion

__init__()

Constructs a null rectangle.

See also

isNull()

__init__(topleft, bottomright)
Parameters:

Constructs a rectangle with the given topLeft and bottomRight corners, both included.

If bottomRight is to higher and to the left of topLeft, the rectangle defined is instead non-inclusive of the corners.

Note

To ensure both points are included regardless of relative order, use span() .

__init__(topleft, size)
Parameters:

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

__init__(left, top, width, height)
Parameters:
  • left – int

  • top – int

  • width – int

  • height – int

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

See also

setRect()

__reduce__()
Return type:

str

__repr__()
Return type:

str

adjust(x1, y1, x2, y2)
Parameters:
  • x1 – int

  • y1 – int

  • x2 – int

  • y2 – int

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

adjusted(x1, y1, x2, y2)
Parameters:
  • x1 – int

  • y1 – int

  • x2 – int

  • y2 – int

Return type:

QRect

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

See also

adjust()

bottom()
Return type:

int

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.

bottomLeft()
Return type:

QPoint

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

bottomRight()
Return type:

QPoint

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).

center()
Return type:

QPoint

Returns the center point of the rectangle.

See also

moveCenter()

contains(p[, proper=false])
Parameters:
  • pQPoint

  • proper – bool

Return type:

bool

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()

contains(r[, proper=false])
Parameters:
  • rQRect

  • proper – bool

Return type:

bool

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).

contains(x, y)
Parameters:
  • x – int

  • y – int

Return type:

bool

This is an overloaded function.

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

contains(x, y, proper)
Parameters:
  • x – int

  • y – int

  • proper – bool

Return type:

bool

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).

getCoords()
Return type:

PyObject

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``.

getRect()
Return type:

PyObject

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

height()
Return type:

int

Returns the height of the rectangle.

intersected(other)
Parameters:

otherQRect

Return type:

QRect

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

../../_images/qrect-intersect.png

See also

intersects() united() operator&=()

intersects(r)
Parameters:

rQRect

Return type:

bool

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()

isEmpty()
Return type:

bool

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.

isNull()
Return type:

bool

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() isValid()

isValid()
Return type:

bool

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() ).

left()
Return type:

int

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

marginsAdded(margins)
Parameters:

marginsQMargins

Return type:

QRect

Returns a rectangle grown by the margins.

See also

operator+=() marginsRemoved() operator-=()

marginsRemoved(margins)
Parameters:

marginsQMargins

Return type:

QRect

Removes the margins from the rectangle, shrinking it.

See also

marginsAdded() operator+=() operator-=()

moveBottom(pos)
Parameters:

pos – int

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

moveBottomLeft(p)
Parameters:

pQPoint

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

moveBottomRight(p)
Parameters:

pQPoint

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

moveCenter(p)
Parameters:

pQPoint

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

See also

center()

moveLeft(pos)
Parameters:

pos – int

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

moveRight(pos)
Parameters:

pos – int

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

moveTo(p)
Parameters:

pQPoint

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

moveTo(x, t)
Parameters:
  • x – int

  • t – int

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

moveTop(pos)
Parameters:

pos – int

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

moveTopLeft(p)
Parameters:

pQPoint

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

moveTopRight(p)
Parameters:

pQPoint

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

normalized()
Return type:

QRect

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. The corners are at the same time changed from being non-inclusive to inclusive.

See also

isValid() isEmpty()

__ne__(rhs)
Parameters:

rhsQRect

Return type:

bool

Returns true if the rectangles lhs and rhs are different, otherwise returns false.

__ne__(rhs)
Parameters:

rhsQRectF

Return type:

bool

__and__(r)
Parameters:

rQRect

Return type:

QRect

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

See also

operator&=() intersected()

__iand__(r)
Parameters:

rQRect

Return type:

QRect

Intersects this rectangle with the given rectangle.

See also

intersected() operator&()

__add__(margins)
Parameters:

marginsQMargins

Return type:

QRect

This is an overloaded function.

Returns the rectangle grown by the margins.

__add__(margins)
Parameters:

marginsQMargins

Return type:

QRect

Returns the rectangle grown by the margins.

__iadd__(margins)
Parameters:

marginsQMargins

Return type:

QRect

Adds the margins to the rectangle, growing it.

See also

marginsAdded() marginsRemoved() operator-=()

__sub__(rhs)
Parameters:

rhsQMargins

Return type:

QRect

Returns the lhs rectangle shrunk by the rhs margins.

__isub__(margins)
Parameters:

marginsQMargins

Return type:

QRect

Returns a rectangle shrunk by the margins.

See also

marginsRemoved() operator+=() marginsAdded()

__eq__(rhs)
Parameters:

rhsQRect

Return type:

bool

Returns true if the rectangles lhs and rhs are equal, otherwise returns false.

__eq__(rhs)
Parameters:

rhsQRectF

Return type:

bool

__or__(r)
Parameters:

rQRect

Return type:

QRect

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

See also

operator|=() united()

__ior__(r)
Parameters:

rQRect

Return type:

QRect

Unites this rectangle with the given rectangle.

See also

united() operator|()

right()
Return type:

int

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.

setBottom(pos)
Parameters:

pos – int

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.

setBottomLeft(p)
Parameters:

pQPoint

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.

setBottomRight(p)
Parameters:

pQPoint

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.

setCoords(x1, y1, x2, y2)
Parameters:
  • x1 – int

  • y1 – int

  • x2 – int

  • y2 – int

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

setHeight(h)
Parameters:

h – int

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

See also

height() setSize()

setLeft(pos)
Parameters:

pos – int

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() .

See also

left() moveLeft()

setRect(x, y, w, h)
Parameters:
  • x – int

  • y – int

  • w – int

  • h – int

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

setRight(pos)
Parameters:

pos – int

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.

See also

right() moveRight()

setSize(s)
Parameters:

sQSize

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

setTop(pos)
Parameters:

pos – int

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() .

See also

top() moveTop()

setTopLeft(p)
Parameters:

pQPoint

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.

setTopRight(p)
Parameters:

pQPoint

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.

setWidth(w)
Parameters:

w – int

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

See also

width() setSize()

setX(x)
Parameters:

x – int

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() .

setY(y)
Parameters:

y – int

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() .

size()
Return type:

QSize

Returns the size of the rectangle.

static span(p1, p2)
Parameters:
Return type:

QRect

Returns a rectangle spanning the two points p1 and p2, including both and everything in between.

toRectF()
Return type:

QRectF

Returns this rectangle as a rectangle with floating point accuracy.

Note

This function, like the QRectF ( QRect ) constructor, preserves the size() of the rectangle, not its bottomRight() corner.

See also

toRect()

top()
Return type:

int

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

topLeft()
Return type:

QPoint

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

topRight()
Return type:

QPoint

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

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

translate(p)
Parameters:

pQPoint

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.

translate(dx, dy)
Parameters:
  • dx – int

  • dy – int

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.

translated(p)
Parameters:

pQPoint

Return type:

QRect

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.

translated(dx, dy)
Parameters:
  • dx – int

  • dy – int

Return type:

QRect

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()

transposed()
Return type:

QRect

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

Returns a copy of the rectangle that has its width and height exchanged:

r = {15, 51, 42, 24}
r = r.transposed() # r == {15, 51, 24, 42}

See also

transposed()

united(other)
Parameters:

otherQRect

Return type:

QRect

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

../../_images/qrect-unite.png

See also

intersected()

width()
Return type:

int

Returns the width of the rectangle.

x()
Return type:

int

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

See also

setX() y() topLeft()

y()
Return type:

int

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

See also

setY() x() topLeft()