QRectF Class

The QRectF class defines a rectangle in the plane using floating point precision. More…

List of all members, including inherited members

Public Functions

Detailed Description

A rectangle is stored as the position of its top-left corner and its width and height, all as double. Unlike QRect, the right and bottom edges are exclusive: right() is left() + width() and bottom() is top() + height(). Use QRect for integer coordinates.

A rectangle is valid when both its width and height are greater than 0. Use normalized() to obtain an equivalent rectangle with non-negative width and height.

See also QRect, QPointF, QSizeF and QMarginsF.

Differences from Qt

Member Function Documentation

[constexpr] QRectF::QRectF()

Constructs a null rectangle, with zero width and height.

See also isNull().

[constexpr] QRectF::QRectF(double left, double top, double width, double height)

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

[constexpr] QRectF::QRectF(const QPointF &topLeft, const QSizeF &s)

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

[constexpr] QRectF::QRectF(const QPointF &topLeft, const QPointF &bottomRight)

Constructs a rectangle with the given topLeft and bottomRight corners.

[constexpr] QRectF::QRectF(const QRect &r)

Constructs a QRectF rectangle from the given integer rectangle r. The right and bottom edges of the result are exclusive, so its width and height equal those of r.

See also toRect().

[constexpr] void QRectF::adjust(double a, double b, double c, double d)

Adds a, b, c and d to the left, top, right and bottom coordinates of the rectangle respectively.

See also adjusted() and setRect().

[constexpr] QRectF QRectF::adjusted(double a, double b, double c, double d) const

Returns a copy of the rectangle with a, b, c and d added to the left, top, right and bottom coordinates respectively.

See also adjust().

[constexpr] double QRectF::bottom() const

Returns the y coordinate of the rectangle's bottom edge, which is top() + height().

See also setBottom() and top().

[constexpr] QPointF QRectF::bottomLeft() const

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

See also topRight().

[constexpr] QPointF QRectF::bottomRight() const

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

See also topLeft().

[constexpr] QPointF QRectF::center() const

Returns the center point of the rectangle.

See also moveCenter().

[constexpr] bool QRectF::contains(const QPointF &p) const

Returns true if the given point p is inside or on the edge of the rectangle; otherwise returns false. A rectangle with zero width or height contains nothing.

See also intersects().

[constexpr] bool QRectF::contains(double x, double y) const

This is an overloaded function.

Returns true if the point (x, y) is inside or on the edge of this rectangle.

[constexpr] bool QRectF::contains(const QRectF &o) const

This is an overloaded function.

Returns true if the rectangle o is inside this rectangle; otherwise returns false. A rectangle with zero width or height never contains, and is never contained by, another rectangle.

[constexpr] void QRectF::getCoords(double *x1, double *y1, double *x2, double *y2) const

Stores the top-left corner in *x1 and *y1 and the bottom-right corner in *x2 and *y2, through x1, y1, x2 and y2.

See also getRect().

[constexpr] void QRectF::getRect(double *x, double *y, double *width, double *height) const

Stores the position of the top-left corner in *x and *y and the size in *width and *height, through x, y, width and height.

See also getCoords().

[constexpr] double QRectF::height() const

Returns the height of the rectangle.

See also setHeight() and width().

[constexpr] QRectF QRectF::intersected(const QRectF &o) const

Returns the intersection of this rectangle and the rectangle o. Returns a null rectangle if they do not intersect.

See also intersects() and united().

[constexpr] bool QRectF::intersects(const QRectF &o) const

Returns true if this rectangle intersects the rectangle o, that is, if they share an area of non-zero size; otherwise returns false.

See also intersected() and contains().

[constexpr] bool QRectF::isEmpty() const

Returns true if the rectangle is empty, that is, its width or height is less than or equal to 0; otherwise returns false.

See also isNull() and isValid().

[constexpr] bool QRectF::isNull() const

Returns true if the rectangle is a null rectangle, that is, its width and height are both exactly 0; otherwise returns false.

See also isEmpty() and isValid().

[constexpr] bool QRectF::isValid() const

Returns true if the rectangle is valid, that is, its width and height are both greater than 0; otherwise returns false.

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

[constexpr] double QRectF::left() const

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

See also setLeft() and right().

[constexpr] QRectF QRectF::marginsAdded(const QMarginsF &m) const

Returns a rectangle grown by the margins m: the left and top edges move outwards by the left and top margins, the right and bottom edges by the right and bottom margins.

See also marginsRemoved().

[constexpr] QRectF QRectF::marginsRemoved(const QMarginsF &m) const

Returns a rectangle shrunk by the margins m.

See also marginsAdded().

[constexpr] void QRectF::moveBottom(double p)

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

See also bottom() and moveTop().

[constexpr] void QRectF::moveBottomLeft(const QPointF &p)

Moves the rectangle so that its bottom-left corner is at p, keeping its size.

[constexpr] void QRectF::moveBottomRight(const QPointF &p)

Moves the rectangle so that its bottom-right corner is at p, keeping its size.

[constexpr] void QRectF::moveCenter(const QPointF &p)

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

See also center().

[constexpr] void QRectF::moveLeft(double p)

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

See also left() and moveRight().

[constexpr] void QRectF::moveRight(double p)

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

See also right() and moveLeft().

[constexpr] void QRectF::moveTo(double x, double y)

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

See also translate().

[constexpr] void QRectF::moveTo(const QPointF &p)

This is an overloaded function.

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

[constexpr] void QRectF::moveTop(double p)

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

See also top() and moveBottom().

[constexpr] void QRectF::moveTopLeft(const QPointF &p)

Moves the rectangle so that its top-left corner is at p, keeping its size.

[constexpr] void QRectF::moveTopRight(const QPointF &p)

Moves the rectangle so that its top-right corner is at p, keeping its size.

[constexpr] QRectF QRectF::normalized() const

Returns a normalized rectangle, that is, one that has a non-negative width and height. If the width or height is negative, the rectangle is moved so that it covers the same area with a positive extent.

See also isValid().

[constexpr] QRectF QRectF::operator&(const QRectF &o) const

Returns the intersection of this rectangle and the rectangle o. Equivalent to intersected().

[constexpr] QRectF & QRectF::operator&=(const QRectF &o)

Sets this rectangle to its intersection with the rectangle o, and returns a reference to this rectangle.

[constexpr] QRectF & QRectF::operator+=(const QMarginsF &m)

Adds the margins m to this rectangle, as marginsAdded() does, and returns a reference to this rectangle.

[constexpr] QRectF & QRectF::operator-=(const QMarginsF &m)

Removes the margins m from this rectangle, as marginsRemoved() does, and returns a reference to this rectangle.

[constexpr] QRectF QRectF::operator|(const QRectF &o) const

Returns the bounding rectangle of this rectangle and the rectangle o. Equivalent to united().

[constexpr] QRectF & QRectF::operator|=(const QRectF &o)

Sets this rectangle to the bounding rectangle of itself and the rectangle o, and returns a reference to this rectangle.

[constexpr] double QRectF::right() const

Returns the x coordinate of the rectangle's right edge, which is left() + width().

See also setRight() and left().

[constexpr] void QRectF::setBottom(double v)

Sets the bottom edge of the rectangle to v, leaving the top edge unchanged and so changing the height.

See also bottom() and moveBottom().

[constexpr] void QRectF::setBottomLeft(const QPointF &p)

Sets the bottom-left corner to p, keeping the top-right corner.

See also bottomLeft() and moveBottomLeft().

[constexpr] void QRectF::setBottomRight(const QPointF &p)

Sets the bottom-right corner to p, keeping the top-left corner.

See also bottomRight() and moveBottomRight().

[constexpr] void QRectF::setCoords(double xa, double ya, double xb, double yb)

Sets the coordinates of the rectangle's top-left corner to (xa, ya), and of its bottom-right corner to (xb, yb).

See also setRect().

[constexpr] void QRectF::setHeight(double v)

Sets the height of the rectangle to v, keeping the top edge.

See also height() and setWidth().

[constexpr] void QRectF::setLeft(double v)

Sets the left edge of the rectangle to v, leaving the right edge unchanged and so changing the width.

See also left() and moveLeft().

[constexpr] void QRectF::setRect(double x, double y, double wd, double ht)

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

See also setCoords().

[constexpr] void QRectF::setRight(double v)

Sets the right edge of the rectangle to v, leaving the left edge unchanged and so changing the width.

See also right() and moveRight().

[constexpr] void QRectF::setSize(const QSizeF &s)

Sets the size of the rectangle to s, keeping the top-left corner.

See also size().

[constexpr] void QRectF::setTop(double v)

Sets the top edge of the rectangle to v, leaving the bottom edge unchanged and so changing the height.

See also top() and moveTop().

[constexpr] void QRectF::setTopLeft(const QPointF &p)

Sets the top-left corner to p, keeping the bottom-right corner.

See also topLeft() and moveTopLeft().

[constexpr] void QRectF::setTopRight(const QPointF &p)

Sets the top-right corner to p, keeping the bottom-left corner.

See also topRight() and moveTopRight().

[constexpr] void QRectF::setWidth(double v)

Sets the width of the rectangle to v, keeping the left edge.

See also width() and setHeight().

[constexpr] void QRectF::setX(double v)

Sets the left edge of the rectangle to v, leaving the right edge unchanged and so changing the width. Equivalent to setLeft().

See also x() and setY().

[constexpr] void QRectF::setY(double v)

Sets the top edge of the rectangle to v, leaving the bottom edge unchanged and so changing the height. Equivalent to setTop().

See also y() and setX().

[constexpr] QSizeF QRectF::size() const

Returns the size of the rectangle.

See also setSize(), width() and height().

QRect QRectF::toAlignedRect() const

Returns the smallest QRect that contains this rectangle, rounding the left and top edges down and the right and bottom edges up.

See also toRect().

[constexpr] double QRectF::top() const

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

See also setTop() and bottom().

[constexpr] QPointF QRectF::topLeft() const

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

See also bottomRight().

[constexpr] QPointF QRectF::topRight() const

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

See also bottomLeft().

QRect QRectF::toRect() const

Returns a QRect with the coordinates of the top-left and bottom-right corners each rounded to the nearest integer.

See also toAlignedRect() and QRectF(const QRect &).

[constexpr] void QRectF::translate(double dx, double dy)

Moves the rectangle dx along the x axis and dy along the y axis, relative to the current position.

See also translated() and moveTo().

[constexpr] void QRectF::translate(const QPointF &p)

This is an overloaded function.

Moves the rectangle by the offset p, relative to the current position.

[constexpr] QRectF QRectF::translated(double dx, double dy) const

Returns a copy of the rectangle that is translated dx along the x axis and dy along the y axis.

See also translate().

[constexpr] QRectF QRectF::translated(const QPointF &p) const

This is an overloaded function.

Returns a copy of the rectangle that is translated by the offset p.

[constexpr] QRectF QRectF::transposed() const

Returns a copy of the rectangle with its width and height exchanged, keeping the top-left corner.

See also QSizeF::transposed().

[constexpr] QRectF QRectF::united(const QRectF &o) const

Returns the bounding rectangle of this rectangle and the rectangle o. If one of the rectangles is null, the other is returned.

See also intersected().

[constexpr] double QRectF::width() const

Returns the width of the rectangle.

See also setWidth() and height().

[constexpr] double QRectF::x() const

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

See also setX() and y().

[constexpr] double QRectF::y() const

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

See also setY() and x().