/*************************************************************************** qpoint.cpp (c) 2000-2012 Benoît Minisini This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. ***************************************************************************/ /**************************************************************************** ** $Id: qt/qpoint.cpp 3.3.4 edited May 27 2003 $ ** ** Implementation of QPoint class ** ** Created : 931028 ** ** Copyright (C) 1992-2000 Trolltech AS. All rights reserved. ** ** This file is part of the kernel module of the Qt GUI Toolkit. ** ** This file may be distributed under the terms of the Q Public License ** as defined by Trolltech AS of Norway and appearing in the file ** LICENSE.QPL included in the packaging of this file. ** ** This file may be distributed and/or modified under the terms of the ** GNU General Public License version 2 as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL included in the ** packaging of this file. ** ** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition ** licenses may use this file in accordance with the Qt Commercial License ** Agreement provided with the Software. ** ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. ** ** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for ** information about Qt Commercial License Agreements. ** See http://www.trolltech.com/qpl/ for QPL licensing information. ** See http://www.trolltech.com/gpl/ for GPL licensing information. ** ** Contact info@trolltech.com if any conditions of this licensing are ** not clear to you. ** **********************************************************************/ #include "qpoint.h" //#include "qdatastream.h" /*! \class QPoint qpoint.h \brief The QPoint class defines a point in the plane. \ingroup images \ingroup graphics \mainclass A point is specified by an x coordinate and a y coordinate. The coordinate type is \c QCOORD (a 32-bit integer). The minimum value of \c QCOORD is \c QCOORD_MIN (-2147483648) and the maximum value is \c QCOORD_MAX (2147483647). The coordinates are accessed by the functions x() and y(); they can be set by setX() and setY() or by the reference functions rx() and ry(). Given a point \e p, the following statements are all equivalent: \code p.setX( p.x() + 1 ); p += QPoint( 1, 0 ); p.rx()++; \endcode A QPoint can also be used as a vector. Addition and subtraction of QPoints are defined as for vectors (each component is added separately). You can divide or multiply a QPoint by an \c int or a \c double. The function manhattanLength() gives an inexpensive approximation of the length of the QPoint interpreted as a vector. Example: \code //QPoint oldPos is defined somewhere else MyWidget::mouseMoveEvent( QMouseEvent *e ) { QPoint vector = e->pos() - oldPos; if ( vector.manhattanLength() > 3 ) ... //mouse has moved more than 3 pixels since oldPos } \endcode QPoints can be compared for equality or inequality, and they can be written to and read from a QStream. \sa QPointArray QSize, QRect */ /***************************************************************************** QPoint member functions *****************************************************************************/ /*! \fn QPoint::QPoint() Constructs a point with coordinates (0, 0) (isNull() returns TRUE). */ /*! \fn QPoint::QPoint( int xpos, int ypos ) Constructs a point with x value \a xpos and y value \a ypos. */ /*! \fn bool QPoint::isNull() const Returns TRUE if both the x value and the y value are 0; otherwise returns FALSE. */ /*! \fn int QPoint::x() const Returns the x coordinate of the point. \sa setX() y() */ /*! \fn int QPoint::y() const Returns the y coordinate of the point. \sa setY() x() */ /*! \fn void QPoint::setX( int x ) Sets the x coordinate of the point to \a x. \sa x() setY() */ /*! \fn void QPoint::setY( int y ) Sets the y coordinate of the point to \a y. \sa y() setX() */ /*! \fn QCOORD &QPoint::rx() Returns a reference to the x coordinate of the point. Using a reference makes it possible to directly manipulate x. Example: \code QPoint p( 1, 2 ); p.rx()--; // p becomes (0, 2) \endcode \sa ry() */ /*! \fn QCOORD &QPoint::ry() Returns a reference to the y coordinate of the point. Using a reference makes it possible to directly manipulate y. Example: \code QPoint p( 1, 2 ); p.ry()++; // p becomes (1, 3) \endcode \sa rx() */ /*! \fn QPoint &QPoint::operator+=( const QPoint &p ) Adds point \a p to this point and returns a reference to this point. Example: \code QPoint p( 3, 7 ); QPoint q( -1, 4 ); p += q; // p becomes (2,11) \endcode */ /*! \fn QPoint &QPoint::operator-=( const QPoint &p ) Subtracts point \a p from this point and returns a reference to this point. Example: \code QPoint p( 3, 7 ); QPoint q( -1, 4 ); p -= q; // p becomes (4,3) \endcode */ /*! \fn QPoint &QPoint::operator*=( int c ) Multiplies this point's x and y by \a c, and returns a reference to this point. Example: \code QPoint p( -1, 4 ); p *= 2; // p becomes (-2,8) \endcode */ /*! \overload QPoint &QPoint::operator*=( double c ) Multiplies this point's x and y by \a c, and returns a reference to this point. Example: \code QPoint p( -1, 4 ); p *= 2.5; // p becomes (-3,10) \endcode Note that the result is truncated because points are held as integers. */ /*! \fn bool operator==( const QPoint &p1, const QPoint &p2 ) \relates QPoint Returns TRUE if \a p1 and \a p2 are equal; otherwise returns FALSE. */ /*! \fn bool operator!=( const QPoint &p1, const QPoint &p2 ) \relates QPoint Returns TRUE if \a p1 and \a p2 are not equal; otherwise returns FALSE. */ /*! \fn const QPoint operator+( const QPoint &p1, const QPoint &p2 ) \relates QPoint Returns the sum of \a p1 and \a p2; each component is added separately. */ /*! \fn const QPoint operator-( const QPoint &p1, const QPoint &p2 ) \relates QPoint Returns \a p2 subtracted from \a p1; each component is subtracted separately. */ /*! \fn const QPoint operator*( const QPoint &p, int c ) \relates QPoint Returns the QPoint formed by multiplying both components of \a p by \a c. */ /*! \overload const QPoint operator*( int c, const QPoint &p ) \relates QPoint Returns the QPoint formed by multiplying both components of \a p by \a c. */ /*! \overload const QPoint operator*( const QPoint &p, double c ) \relates QPoint Returns the QPoint formed by multiplying both components of \a p by \a c. Note that the result is truncated because points are held as integers. */ /*! \overload const QPoint operator*( double c, const QPoint &p ) \relates QPoint Returns the QPoint formed by multiplying both components of \a p by \a c. Note that the result is truncated because points are held as integers. */ /*! \overload const QPoint operator-( const QPoint &p ) \relates QPoint Returns the QPoint formed by changing the sign of both components of \a p, equivalent to \c{QPoint(0,0) - p}. */ /*! \fn QPoint &QPoint::operator/=( int c ) Divides both x and y by \a c, and returns a reference to this point. Example: \code QPoint p( -2, 8 ); p /= 2; // p becomes (-1,4) \endcode */ /*! \overload QPoint &QPoint::operator/=( double c ) Divides both x and y by \a c, and returns a reference to this point. Example: \code QPoint p( -3, 10 ); p /= 2.5; // p becomes (-1,4) \endcode Note that the result is truncated because points are held as integers. */ /*! \fn const QPoint operator/( const QPoint &p, int c ) \relates QPoint Returns the QPoint formed by dividing both components of \a p by \a c. */ /*! \overload const QPoint operator/( const QPoint &p, double c ) \relates QPoint Returns the QPoint formed by dividing both components of \a p by \a c. Note that the result is truncated because points are held as integers. */ void QPoint::warningDivByZero() { #if defined(QT_CHECK_MATH) qWarning( "QPoint: Division by zero error" ); #endif } /***************************************************************************** QPoint stream functions *****************************************************************************/ #ifndef QT_NO_DATASTREAM /*! \relates QPoint Writes point \a p to the stream \a s and returns a reference to the stream. \sa \link datastreamformat.html Format of the QDataStream operators \endlink */ QDataStream &operator<<( QDataStream &s, const QPoint &p ) { if ( s.version() == 1 ) s << (Q_INT16)p.x() << (Q_INT16)p.y(); else s << (Q_INT32)p.x() << (Q_INT32)p.y(); return s; } /*! \relates QPoint Reads a QPoint from the stream \a s into point \a p and returns a reference to the stream. \sa \link datastreamformat.html Format of the QDataStream operators \endlink */ QDataStream &operator>>( QDataStream &s, QPoint &p ) { if ( s.version() == 1 ) { Q_INT16 x, y; s >> x; p.rx() = x; s >> y; p.ry() = y; } else { Q_INT32 x, y; s >> x; p.rx() = x; s >> y; p.ry() = y; } return s; } #endif // QT_NO_DATASTREAM /*! Returns the sum of the absolute values of x() and y(), traditionally known as the "Manhattan length" of the vector from the origin to the point. The tradition arises because such distances apply to travelers who can only travel on a rectangular grid, like the streets of Manhattan. This is a useful, and quick to calculate, approximation to the true length: sqrt(pow(x(),2)+pow(y(),2)). */ int QPoint::manhattanLength() const { return QABS(x())+QABS(y()); }