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#include "qline.h"

#include "qdebug.h"

#include "qdatastream.h"

#include "qmath.h"

#include <private/qnumeric_p.h>

QT_BEGIN_NAMESPACE

/*!

    \class QLine

    \ingroup painting

    \brief The QLine class provides a two-dimensional vector using

    integer precision.

    A QLine describes a finite length line (or a line segment) on a

    two-dimensional surface. The start and end points of the line are

    specified using integer point accuracy for coordinates. Use the

    QLineF constructor to retrieve a floating point copy.

    \table

    \row

        \o \inlineimage qline-point.png

        \o \inlineimage qline-coordinates.png

    \endtable

    The positions of the line's start and end points can be retrieved

    using the p1(), x1(), y1(), p2(), x2(), and y2() functions. The

    dx() and dy() functions return the horizontal and vertical

    components of the line. Use isNull() to determine whether the

    QLine represents a valid line or a null line.

    Finally, the line can be translated a given offset using the

    translate() function.

    \sa QLineF, QPolygon, QRect

*/

/*!

    \fn QLine::QLine()

    Constructs a null line.

*/

/*!

    \fn QLine::QLine(const QPoint &p1, const QPoint &p2)

    Constructs a line object that represents the line between \a p1 and

    \a p2.

*/

/*!

    \fn QLine::QLine(int x1, int y1, int x2, int y2)

    Constructs a line object that represents the line between (\a x1, \a y1) and

    (\a x2, \a y2).

*/

/*!

    \fn bool QLine::isNull() const

    Returns true if the line is not set up with valid start and end point;

    otherwise returns false.

*/

/*!

    \fn QPoint QLine::p1() const

    Returns the line's start point.

    \sa x1(), y1(), p2()

*/

/*!

    \fn QPoint QLine::p2() const

    Returns the line's end point.

    \sa x2(), y2(), p1()

*/

/*!

    \fn int QLine::x1() const

    Returns the x-coordinate of the line's start point.

    \sa p1()

*/

/*!

    \fn int QLine::y1() const

    Returns the y-coordinate of the line's start point.

    \sa p1()

*/

/*!

    \fn int QLine::x2() const

    Returns the x-coordinate of the line's end point.

    \sa p2()

*/

/*!

    \fn int QLine::y2() const

    Returns the y-coordinate of the line's end point.

    \sa p2()

*/

/*!

    \fn int QLine::dx() const

    Returns the horizontal component of the line's vector.

    \sa dy()

*/

/*!

    \fn int QLine::dy() const

    Returns the vertical component of the line's vector.

    \sa dx()

*/

/*!

    \fn bool QLine::operator!=(const QLine &line) const

    Returns true if the given \a line is not the same as \e this line.

    A line is different from another line if any of their start or

    end points differ, or the internal order of the points is different.

*/

/*!

    \fn bool QLine::operator==(const QLine &line) const

    Returns true if the given \a line is the same as \e this line.

    A line is identical to another line if the start and end points

    are identical, and the internal order of the points is the same.

*/

/*!

    \fn void QLine::translate(const QPoint &offset)

    Translates this line by the given \a offset.

*/

/*!

    \fn void QLine::translate(int dx, int dy)

    \overload

    Translates this line the distance specified by \a dx and \a dy.

*/

/*!

    \fn QLine QLine::translated(const QPoint &offset) const

    \since 4.4

    Returns this line translated by the given \a offset.

*/

/*!

    \fn QLine QLine::translated(int dx, int dy) const

    \overload

    \since 4.4

    Returns this line translated the distance specified by \a dx and \a dy.

*/

/*!

    \fn void QLine::setP1(const QPoint &p1)

    \since 4.4

    Sets the starting point of this line to \a p1.

    \sa setP2(), p1()

*/

/*!

    \fn void QLine::setP2(const QPoint &p2)

    \since 4.4

    Sets the end point of this line to \a p2.

    \sa setP1(), p2()

*/

/*!

    \fn void QLine::setPoints(const QPoint &p1, const QPoint &p2)

    \since 4.4

    Sets the start point of this line to \a p1 and the end point of this line to \a p2.

    \sa setP1(), setP2(), p1(), p2()

*/

/*!

    \fn void QLine::setLine(int x1, int y1, int x2, int y2)

    \since 4.4

    Sets this line to the start in \a x1, \a y1 and end in \a x2, \a y2.

    \sa setP1(), setP2(), p1(), p2()

*/

#ifndef QT_NO_DEBUG_STREAM

QDebug operator<<(QDebug d, const QLine &p)

{

    d << "QLine(" << p.p1() << ',' << p.p2() << ')';

    return d;

}

#endif

#ifndef QT_NO_DATASTREAM

/*!

    \relates QLine

    Writes the given \a line to the given \a stream and returns a

    reference to the stream.

    \sa {Format of the QDataStream Operators}

*/

QDataStream &operator<<(QDataStream &stream, const QLine &line)

{

    stream << line.p1() << line.p2();

    return stream;

}

/*!

    \relates QLine

    Reads a line from the given \a stream into the given \a line and

    returns a reference to the stream.

    \sa {Format of the QDataStream Operators}

*/

QDataStream &operator>>(QDataStream &stream, QLine &line)

{

    QPoint p1, p2;

    stream >> p1;

    stream >> p2;

    line = QLine(p1, p2);

    return stream;

}

#endif // QT_NO_DATASTREAM

#ifndef M_2PI

#define M_2PI 6.28318530717958647692528676655900576

#endif

/*!

    \class QLineF

    \ingroup painting

    \brief The QLineF class provides a two-dimensional vector using

    floating point precision.

    A QLineF describes a finite length line (or line segment) on a

    two-dimensional surface. QLineF defines the start and end points

    of the line using floating point accuracy for coordinates.  Use

    the toLine() function to retrieve an integer based copy of this

    line.

    \table

    \row

        \o \inlineimage qline-point.png

        \o \inlineimage qline-coordinates.png

    \endtable

    The positions of the line's start and end points can be retrieved

    using the p1(), x1(), y1(), p2(), x2(), and y2() functions. The

    dx() and dy() functions return the horizontal and vertical

    components of the line, respectively.

    The line's length can be retrieved using the length() function,

    and altered using the setLength() function.  Similarly, angle()

    and setAngle() are respectively used for retrieving and altering

    the angle of the line. Use the isNull()

    function to determine whether the QLineF represents a valid line

    or a null line.

    The intersect() function determines the IntersectType for this

    line and a given line, while the angle() function returns the

    angle between the lines. In addition, the unitVector() function

    returns a line that has the same starting point as this line, but

    with a length of only 1, while the normalVector() function returns

    a line that is perpendicular to this line with the same starting

    point and length.

    Finally, the line can be translated a given offset using the

    translate() function, and can be traversed using the pointAt()

    function.

    \sa QLine, QPolygonF, QRectF

*/

/*!

    \enum QLineF::IntersectType

    Describes the intersection between two lines.

    \table

    \row

    \o \inlineimage qlinef-unbounded.png

    \o \inlineimage qlinef-bounded.png

    \row

    \o QLineF::UnboundedIntersection

    \o QLineF::BoundedIntersection

    \endtable

    \value NoIntersection Indicates that the lines do not intersect;

    i.e. they are parallel.

    \value UnboundedIntersection The two lines intersect, but not

    within the range defined by their lengths. This will be the case

    if the lines are not parallel. 

    intersect() will also return this value if the intersect point is

    within the start and end point of only one of the lines.

    \value BoundedIntersection The two lines intersect with each other

    within the start and end points of each line.

    \sa intersect()

*/

/*!

    \fn QLineF::QLineF()

    Constructs a null line.

*/

/*!

    \fn QLineF::QLineF(const QPointF &p1, const QPointF &p2)

    Constructs a line object that represents the line between \a p1 and

    \a p2.

*/

/*!

    \fn QLineF::QLineF(qreal x1, qreal y1, qreal x2, qreal y2)

    Constructs a line object that represents the line between (\a x1, \a y1) and

    (\a x2, \a y2).

*/

/*!

    \fn QLineF::QLineF(const QLine &line)

    Construct a QLineF object from the given integer-based \a line.

    \sa toLine()

*/

/*!

    Returns true if the line is not set up with valid start and end point;

    otherwise returns false.

*/

bool QLineF::isNull() const

{

    return (qFuzzyCompare(pt1.x(), pt2.x()) && qFuzzyCompare(pt1.y(), pt2.y())) ? true : false;

}

/*!

    \fn QPointF QLineF::p1() const

    Returns the line's start point.

    \sa x1(), y1(), p2()

*/

/*!

    \fn QPointF QLineF::p2() const

    Returns the line's end point.

    \sa x2(), y2(), p1()

*/

/*!

    \fn QLine QLineF::toLine() const

    Returns an integer based copy of this line.

    Note that the returned line's start and end points are rounded to

    the nearest integer.

    \sa QLineF()

*/

/*!

    \fn qreal QLineF::x1() const

    Returns the x-coordinate of the line's start point.

    \sa p1()

*/

/*!

    \fn qreal QLineF::y1() const

    Returns the y-coordinate of the line's start point.

    \sa p1()

*/

/*!

    \fn qreal QLineF::x2() const

    Returns the x-coordinate of the line's end point.

    \sa p2()

*/

/*!

    \fn qreal QLineF::y2() const

    Returns the y-coordinate of the line's end point.

    \sa p2()

*/

/*!

    \fn qreal QLineF::dx() const

    Returns the horizontal component of the line's vector.

    \sa dy(), pointAt()

*/

/*!

    \fn qreal QLineF::dy() const

    Returns the vertical component of the line's vector.

    \sa dx(), pointAt()

*/

/*!

    \fn QLineF::setLength(qreal length)

    Sets the length of the line to the given \a length. QLineF will

    move the end point - p2() - of the line to give the line its new length.

    If the line is a null line, the length will remain zero regardless

    of the length specified. 

    \sa length(), isNull()

*/

/*!

    \fn QLineF QLineF::normalVector() const

    Returns a line that is perpendicular to this line with the same starting

    point and length.

    \image qlinef-normalvector.png

    \sa unitVector()

*/

/*!

    \fn bool QLineF::operator!=(const QLineF &line) const

    Returns true if the given \a line is not the same as \e this line.

    A line is different from another line if their start or end points

    differ, or the internal order of the points is different.