QRect(3qt)QRect(3qt)NAMEQRect - Defines a rectangle in the plane
#include <qrect.h>
Public Members
QRect ()
QRect ( const QPoint & topleft, const QPoint & bottomright
)
QRect ( const QPoint & topleft, const QSize & size )
QRect ( int left, int top, int width, int height )
bool isNull () const
bool isEmpty () const
bool isValid () const
QRect normalize () const
int left () const
int top () const
int right () const
int bottom () const
QCOORD& rLeft ()
QCOORD& rTop ()
QCOORD& rRight ()
QCOORD& rBottom ()
int x () const
int y () const
void setLeft ( int pos )
void setTop ( int pos )
void setRight ( int pos )
void setBottom ( int pos )
void setX ( int x )
void setY ( int y )
QPoint topLeft () const
QPoint bottomRight () const
QPoint topRight () const
QPoint bottomLeft () const
QPoint center () const
void rect ( int * x, int * y, int * w, int * h ) const
void coords ( int * x1, int * y1, int * x2, int * y2 )
const
void moveTopLeft ( const QPoint & p )
void moveBottomRight ( const QPoint & p )
void moveTopRight ( const QPoint & p )
void moveBottomLeft ( const QPoint & p )
void moveCenter ( const QPoint & p )
void moveBy ( int dx, int dy )
void setRect ( int x, int y, int w, int h )
void setCoords ( int x1, int y1, int x2, int y2 )
QSize size () const
int width () const
int height () const
void setWidth ( int w )
void setHeight ( int h )
void setSize ( const QSize & s )
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QRect(3qt)QRect(3qt)QRect operator| ( const QRect & r ) const
QRect operator& ( const QRect & r ) const
QRect& operator|= ( const QRect & r )
QRect& operator&= ( const QRect & r )
bool contains ( const QPoint & p, bool proper=FALSE )
const
bool contains ( int x, int y, bool proper=FALSE ) const
bool contains ( const QRect & r, bool proper=FALSE ) const
QRect unite ( const QRect & r ) const
QRect intersect ( const QRect & r ) const
bool intersects ( const QRect & r ) const
RELATED FUNCTION DOCUMENTATION
(Note that these are not member functions.)
bool operator== (const QRect & r1, const QRect & r2)
QDataStream & operator>> (QDataStream & s, QRect & r)
QDataStream & operator<< (QDataStream & s, const QRect &
r)
bool operator!= (const QRect & r1, const QRect & r2)
DESCRIPTION
The QRect class defines a rectangle in the plane.
A rectangle is internally represented as an upper left
corner and a bottom right corner, but it is normally
expressed as an upper left corner and a size.
The coordinate type is QCOORD (defined in qwindowdefs.h as
int). The minimum value of QCOORD is QCOORD_MIN
(-2147483648) and the maximum value is QCOORD_MAX
(2147483647).
Note that the size (width and height) of a rectangle might
be different from what you are used to. If the top left
corner and the bottom right corner are the same, then the
height and the width of the rectangle will both be 1.
Generally, width = right - left + 1 and height = bottom -
top + 1. We designed it this way to make it correspond to
rectangular spaces used by drawing functions, where the
width and height denote a number of pixels. For example,
drawing a rectangle with width and height 1 draws a single
pixel.
The default coordinate system has origin (0,0) in the top
left corner, the positive direction of the y axis is
downwards and the positive x axis is from the left to the
right.
See also QPoint and QSize.
Examples: xform/xform.cpp forever/forever.cpp
desktop/desktop.cpp movies/main.cpp
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QRect(3qt)QRect(3qt)MEMBER FUNCTION DOCUMENTATIONQRect::QRect ()
Constructs an invalid rectangle.
QRect::QRect ( const QPoint & topLeft, const QPoint & bottomRight
)
Constructs a rectangle with topLeft as the top left corner
and bottomRight as the bottom right corner.
QRect::QRect ( const QPoint & topLeft, const QSize & size )
Constructs a rectangle with topLeft as the top left corner
and size as the rectangle size.
QRect::QRect ( int left, int top, int width, int height )
Constructs a rectangle with the top, left corner and width
and height.
Example (creates three identical rectangles):
QRect r1( QPoint(100,200), QPoint(110,215) );
QRect r2( QPoint(100,200), QSize(11,16) );
QRect r3( 100, 200, 11, 16 );
int QRect::bottom () const
Returns the bottom coordinate of the rectangle.
See also top(), setBottom(), bottomLeft() and
bottomRight().
Examples: desktop/desktop.cpp
QPoint QRect::bottomLeft () const
Returns the bottom left position of the rectangle.
See also moveBottomLeft(), bottomRight(), topLeft(),
topRight(), bottom() and left().
QPoint QRect::bottomRight () const
Returns the bottom right position of the rectangle.
See also moveBottomRight(), bottomLeft(), topLeft(),
topRight(), bottom() and right().
QPoint QRect::center () const
Returns the center point of the rectangle.
See also moveCenter(), topLeft(), topRight(), bottomLeft()
and bottomRight().
bool QRect::contains ( const QPoint & p, bool proper=FALSE )
const
Returns TRUE if the point p is inside or on the edge of
the rectangle.
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QRect(3qt)QRect(3qt)
If proper is TRUE, this function returns TRUE only if p is
inside (not on the edge).
bool QRect::contains ( const QRect & r, bool proper=FALSE ) const
Returns TRUE if the rectangle r is inside this rectangle.
If proper is TRUE, this function returns TRUE only if r is
entirely inside (not on the edge).
See also unite(), intersect() and intersects().
bool QRect::contains ( int x, int y, bool proper=FALSE ) const
\overload bool QRect::contains( const QPoint &p, bool
proper ) const.
void QRect::coords ( int * xp1, int * yp1, int * xp2, int * yp2 )
const
Extracts the rectangle parameters as the top left point
and the bottom right point.
See also setCoords() and rect().
int QRect::height () const
Returns the height of the rectangle. The height includes
both the top and bottom edges, ie. height = bottom - top +
1.
See also width(), size() and setHeight().
Examples: xform/xform.cpp desktop/desktop.cpp
movies/main.cpp
QRect QRect::intersect ( const QRect & r ) constr.intersect(s)
is equivalent to
r&s
bool QRect::intersects ( const QRect & r ) const
Returns TRUE if this rectangle intersects with r (there is
at least one pixel which is within both rectangles).
See also intersect() and contains().
bool QRect::isEmpty () const
Returns TRUE if the rectangle is empty, otherwise FALSE.
An empty rectangle has a left() > right() or top() >
bottom().
An empty rectangle is not valid.
isEmpty() == !isValid()Trolltech AS 13 June 2001 4
QRect(3qt)QRect(3qt)
See also isNull() and isValid().
bool QRect::isNull () const
Returns TRUE if the rectangle is a null rectangle,
otherwise FALSE.
A null rectangle has both the width and the height set to
0, that is right() == left() - 1 and bottom() == top()-
1.
Remember that if right() == left() and bottom() == top(),
then the rectangle has width 1 and height 1.
A null rectangle is also empty.
A null rectangle is not valid.
See also isEmpty() and isValid().
bool QRect::isValid () const
Returns TRUE if the rectangle is valid, or FALSE if it is
invalid (empty).
A valid rectangle has a left() <= right() and top() <=
bottom().
isValid() == !isEmpty()
See also isNull(), isEmpty() and normalize().
int QRect::left () const
Returns the left coordinate of the rectangle. Identical to
x().
See also x(), top(), right(), setLeft(), topLeft() and
bottomLeft().
Examples: xform/xform.cpp desktop/desktop.cpp
void QRect::moveBottomLeft ( const QPoint & p )
Sets the bottom left position of the rectangle to p,
leaving the size unchanged.
See also bottomLeft(), moveBottomRight(), moveTopLeft(),
moveTopRight(), setBottom() and setLeft().
void QRect::moveBottomRight ( const QPoint & p )
Sets the bottom right position of the rectangle to p,
leaving the size unchanged.
See also bottomRight(), moveBottomLeft(), moveTopLeft(),
moveTopRight(), setBottom() and setRight().
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QRect(3qt)QRect(3qt)void QRect::moveBy ( 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
moves the rectangle rightwards and/or downwards.).
Examples: xform/xform.cpp
void QRect::moveCenter ( const QPoint & p )
Sets the center point of the rectangle to p, leaving the
size unchanged.
See also center(), moveTopLeft(), moveTopRight(),
moveBottomLeft() and moveBottomRight().
void QRect::moveTopLeft ( const QPoint & p )
Sets the top left position of the rectangle to p, leaving
the size unchanged.
See also topLeft(), moveTopRight(), moveBottomLeft(),
moveBottomRight(), setTop() and setLeft().
Examples: xform/xform.cpp
void QRect::moveTopRight ( const QPoint & p )
Sets the top right position of the rectangle to p, leaving
the size unchanged.
See also topRight(), moveTopLeft(), moveBottomLeft(),
moveBottomRight(), setTop() and setRight().
QRect QRect::normalize () const
Returns a normalized rectangle, i.e. one that has a non-
negative width and height.
It swaps left and right if left() > right(), and swaps top
and bottom if top() > bottom().
See also isValid().
QRect QRect::operator& ( const QRect & r ) const
Returns the intersection of this rectangle and r.
Returns an empty rectangle if there is no intersection.
See also operator&=(), operator|(), isEmpty(),
intersects() and contains().
QRect& QRect::operator&= ( const QRect & r )
Intersects this rectangle with r.
QRect QRect::operator| ( const QRect & r ) const
Returns the bounding rectangle of this and r.
The bounding rectangle of a nonempty rectangle and an
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QRect(3qt)QRect(3qt)
empty or invalid rectangle is defined to be the nonempty
rectangle.
See also operator|=(), operator&(), intersects() and
contains().
QRect& QRect::operator|= ( const QRect & r )
Unites this rectangle with r.
QCOORD & QRect::rBottom ()
Returns the reference to the bottom coordinate of the
rectangle.
See also rLeft(), rTop() and rRight().
QCOORD & QRect::rLeft ()
Returns the reference to the left coordinate of the
rectangle.
See also rTop(), rRight() and rBottom().
QCOORD & QRect::rRight ()
Returns the reference to the right coordinate of the
rectangle.
See also rLeft(), rTop() and rBottom().
QCOORD & QRect::rTop ()
Returns the reference to the top coordinate of the
rectangle.
See also rLeft(), rRight() and rBottom().
void QRect::rect ( int * x, int * y, int * w, int * h ) const
Extracts the rectangle parameters as the position and the
size.
See also setRect() and coords().
int QRect::right () const
Returns the right coordinate of the rectangle.
See also left(), setRight(), topRight() and bottomRight().
Examples: desktop/desktop.cpp
void QRect::setBottom ( int pos )
Sets the bottom edge of the rectangle. May change the
height, but will never change the top edge of the
rectangle.
See also bottom(), setTop() and setHeight().
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QRect(3qt)QRect(3qt)void QRect::setCoords ( int xp1, int yp1, int xp2, int yp2 )
Sets the coordinates of the rectangle's top left corner to
(xp1,yp1), and the coordinates of its bottom right corner
to (xp2,yp2).
See also coords() and setRect().
void QRect::setHeight ( int h )
Sets the height of the rectangle to h. The top edge is not
moved, but the bottom edge may be moved.
See also height(), setTop(), setBottom() and setSize().
Examples: desktop/desktop.cpp
void QRect::setLeft ( int pos )
Sets the left edge of the rectangle. May change the width,
but will never change the right edge of the rectangle.
Identical to setX().
See also left(), setTop() and setWidth().
void 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 (w,h).
See also rect() and setCoords().
void QRect::setRight ( int pos )
Sets the right edge of the rectangle. May change the
width, but will never change the left edge of the
rectangle.
See also right(), setLeft() and setWidth().
void QRect::setSize ( const QSize & s )
Sets the size of the rectangle to s. The top left corner
is not moved.
See also size(), setWidth() and setHeight().
Examples: xform/xform.cpp
void QRect::setTop ( int pos )
Sets the top edge of the rectangle. May change the height,
but will never change the bottom edge of the rectangle.
Identical to setY().
See also top(), setBottom() and setHeight().
void QRect::setWidth ( int w )
Sets the width of the rectangle to w. The right edge is
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QRect(3qt)QRect(3qt)
changed, but not the left edge.
See also width(), setLeft(), setRight() and setSize().
Examples: desktop/desktop.cpp
void QRect::setX ( int x )
Sets the x position of the rectangle (its left end). May
change the width, but will never change the right edge of
the rectangle.
Identical to setLeft().
See also x() and setY().
void QRect::setY ( int y )
Sets the y position of the rectangle (its top). May change
the height, but will never change the bottom edge of the
rectangle.
Identical to setTop().
See also y() and setX().
QSize QRect::size () const
Returns the size of the rectangle.
See also width() and height().
Examples: desktop/desktop.cpp movies/main.cpp
int QRect::top () const
Returns the top coordinate of the rectangle. Identical to
y().
See also y(), left(), bottom(), setTop(), topLeft() and
topRight().
Examples: xform/xform.cpp desktop/desktop.cpp
QPoint QRect::topLeft () const
Returns the top left position of the rectangle.
See also moveTopLeft(), topRight(), bottomLeft(),
bottomRight(), left() and top().
QPoint QRect::topRight () const
Returns the top right position of the rectangle.
See also moveTopRight(), topLeft(), bottomLeft(),
bottomRight(), top() and right().
QRect QRect::unite ( const QRect & r ) constr.unite(s)Trolltech AS 13 June 2001 9
QRect(3qt)QRect(3qt)
is equivalent to
r|s
Examples: xform/xform.cpp
int QRect::width () const
Returns the width of the rectangle. The width includes
both the left and right edges, ie. width = right - left +
1.
See also height(), size() and setHeight().
Examples: xform/xform.cpp desktop/desktop.cpp
movies/main.cpp
int QRect::x () const
Returns the left coordinate of the rectangle. Identical to
left().
See also left(), y() and setX().
Examples: xform/xform.cpp desktop/desktop.cpp
movies/main.cpp
int QRect::y () const
Returns the top coordinate of the rectangle. Identical to
top().
See also top(), x() and setY().
Examples: xform/xform.cpp desktop/desktop.cpp
movies/main.cpp
RELATED FUNCTION DOCUMENTATIONbool operator== (const QRect & r1, const QRect & r2)
Returns TRUE if r1 and r2 are equal, or FALSE if they are
different.
QDataStream & operator>> (QDataStream & s, QRect & r)
Reads a QRect from the stream and returns a reference to
the stream.
See also Format of the QDataStream operators
QDataStream & operator<;< (QDataStream & s, const QRect & r)
Writes a QRect to the stream and returns a reference to
the stream.
See also Format of the QDataStream operators
bool operator!= (const QRect & r1, const QRect & r2)
Returns TRUE if r1 and r2 are different, or FALSE if they
are equal.
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QRect(3qt)QRect(3qt)SEE ALSO
http://doc.trolltech.com/qrect.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2001 Trolltech AS,
http://www.trolltech.com. See the license file included
in the distribution for a complete license statement.
AUTHOR
Generated automatically from the source code.
BUGS
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http://doc.trolltech.com/bughowto.html. Good bug reports
make our job much simpler. Thank you.
In case of content or formattting problems with this
manual page, please report them to qt-bugs@trolltech.com.
Please include the name of the manual page (qrect.3qt) and
the Qt version (2.3.1).
Trolltech AS 13 June 2001 11
