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#include "qpolygon.h"

#include "qrect.h"

#include "qdatastream.h"

#include "qmatrix.h"

#include "qdebug.h"

#include "qpainterpath.h"

#include "qvariant.h"

#include "qpainterpath_p.h"

#include "qbezier_p.h"

#include <stdarg.h>

QT_BEGIN_NAMESPACE

//same as qt_painterpath_isect_line in qpainterpath.cpp

static void qt_polygon_isect_line(const QPointF &p1, const QPointF &p2, const QPointF &pos,

                                  int *winding)

{

    qreal x1 = p1.x();

    qreal y1 = p1.y();

    qreal x2 = p2.x();

    qreal y2 = p2.y();

    qreal y = pos.y();

    int dir = 1;

    if (qFuzzyCompare(y1, y2)) {

        // ignore horizontal lines according to scan conversion rule

        return;

    } else if (y2 < y1) {

        qreal x_tmp = x2; x2 = x1; x1 = x_tmp;

        qreal y_tmp = y2; y2 = y1; y1 = y_tmp;

        dir = -1;

    }

    if (y >= y1 && y < y2) {

        qreal x = x1 + ((x2 - x1) / (y2 - y1)) * (y - y1);

        // count up the winding number if we're

        if (x<=pos.x()) {

            (*winding) += dir;

        }

    }

}

/*!

    \class QPolygon

    \brief The QPolygon class provides a vector of points using

    integer precision.

    \reentrant

    \ingroup painting

    \ingroup shared

    A QPolygon object is a QVector<QPoint>.  The easiest way to add

    points to a QPolygon is to use QVector's streaming operator, as

    illustrated below:

    \snippet doc/src/snippets/polygon/polygon.cpp 0

    In addition to the functions provided by QVector, QPolygon

    provides some point-specific functions.

    Each point in a polygon can be retrieved by passing its index to

    the point() function. To populate the polygon, QPolygon provides

    the setPoint() function to set the point at a given index, the

    setPoints() function to set all the points in the polygon

    (resizing it to the given number of points), and the putPoints()

    function which copies a number of given points into the polygon

    from a specified index (resizing the polygon if necessary).

    QPolygon provides the boundingRect() and translate() functions for

    geometry functions. Use the QMatrix::map() function for more

    general transformations of QPolygons.

    The QPolygon class is \l {Implicit Data Sharing}{implicitly

    shared}.

    \sa QVector, QPolygonF, QLine

*/

/*****************************************************************************

  QPolygon member functions

 *****************************************************************************/

/*!

    \fn QPolygon::QPolygon()

    Constructs a polygon with no points.

    \sa QVector::isEmpty()

*/

/*!

    \fn QPolygon::QPolygon(int size)

    Constructs a polygon of the given \a size. Creates an empty

    polygon if \a size == 0.

    \sa QVector::isEmpty()

*/

/*!

    \fn QPolygon::QPolygon(const QPolygon &polygon)

    Constructs a copy of the given \a polygon.

    \sa setPoints()

*/

/*!

    \fn QPolygon::QPolygon(const QVector<QPoint> &points)

    Constructs a polygon containing the specified \a points.

    \sa setPoints()

*/

/*!

    \fn QPolygon::QPolygon(const QRect &rectangle, bool closed)

    Constructs a polygon from the given \a rectangle.  If \a closed is

    false, the polygon just contains the four points of the rectangle

    ordered clockwise, otherwise the polygon's fifth point is set to

    \a {rectangle}.topLeft().

    Note that the bottom-right corner of the rectangle is located at

    (rectangle.x() + rectangle.width(), rectangle.y() +

    rectangle.height()).

    \sa setPoints()

*/

QPolygon::QPolygon(const QRect &r, bool closed)

{

    reserve(closed ? 5 : 4);

    *this << QPoint(r.x(), r.y())

          << QPoint(r.x() + r.width(), r.y())

          << QPoint(r.x() + r.width(), r.y() + r.height())

          << QPoint(r.x(), r.y() + r.height());

    if (closed)

        *this << QPoint(r.left(), r.top());

}

/*!

    \internal

    Constructs a point array with \a nPoints points, taken from the

    \a points array.

    Equivalent to setPoints(nPoints, points).

*/

QPolygon::QPolygon(int nPoints, const int *points)

{

    setPoints(nPoints, points);

}

/*!

    \fn QPolygon::~QPolygon()

    Destroys the polygon.

*/

/*!

    Translates all points in the polygon by (\a{dx}, \a{dy}).

    \sa translated()

*/

void QPolygon::translate(int dx, int dy)

{

    if (dx == 0 && dy == 0)

        return;

    register QPoint *p = data();

    register int i = size();

    QPoint pt(dx, dy);

    while (i--) {

        *p += pt;

        ++p;

    }

}

/*!

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

    \overload

    Translates all points in the polygon by the given \a offset.

    \sa translated()

*/

/*!

    Returns a copy of the polygon that is translated by (\a{dx}, \a{dy}).

    \since 4.6

    \sa translate()

*/

QPolygon QPolygon::translated(int dx, int dy) const

{

    QPolygon copy(*this);

    copy.translate(dx, dy);

    return copy;

}

/*!

    \fn void QPolygon::translated(const QPoint &offset) const

    \overload

    \since 4.6

    Returns a copy of the polygon that is translated by the given \a offset.

    \sa translate()

*/

/*!

    Extracts the coordinates of the point at the given \a index to

    *\a{x} and *\a{y} (if they are valid pointers).

    \sa setPoint()

*/

void QPolygon::point(int index, int *x, int *y) const

{

    QPoint p = at(index);

    if (x)

        *x = (int)p.x();

    if (y)

        *y = (int)p.y();

}

/*!

    \fn QPoint QPolygon::point(int index) const

    \overload

    Returns the point at the given \a index.

*/

/*!

    \fn void QPolygon::setPoint(int index, const QPoint &point)

    \overload

    Sets the point at the given \a index to the given \a point.

*/

/*!

    \fn void QPolygon::setPoint(int index, int x, int y)

    Sets the point at the given \a index to the point specified by

    (\a{x}, \a{y}).

    \sa point(), putPoints(), setPoints(),

*/

/*!

    Resizes the polygon to \a nPoints and populates it with the given

    \a points.

    The example code creates a polygon with two points (10, 20) and

    (30, 40):

    \snippet doc/src/snippets/polygon/polygon.cpp 2

    \sa setPoint() putPoints()

*/

void QPolygon::setPoints(int nPoints, const int *points)

{

    resize(nPoints);

    int i = 0;

    while (nPoints--) {

        setPoint(i++, *points, *(points+1));

        points += 2;

    }

}

/*!

    \overload

    Resizes the polygon to \a nPoints and populates it with the points

    specified by the variable argument list.  The points are given as a

    sequence of integers, starting with \a firstx then \a firsty, and

    so on.

    The example code creates a polygon with two points (10, 20) and

    (30, 40):

    \snippet doc/src/snippets/polygon/polygon.cpp 3

*/

void QPolygon::setPoints(int nPoints, int firstx, int firsty, ...)

{

    va_list ap;

    resize(nPoints);

    setPoint(0, firstx, firsty);

    int i = 0, x, y;

    va_start(ap, firsty);

    while (--nPoints) {

        x = va_arg(ap, int);

        y = va_arg(ap, int);

        setPoint(++i, x, y);

    }

    va_end(ap);

}

/*!

    \overload

    \internal

    Copies \a nPoints points from the \a points coord array into this

    point array, and resizes the point array if \c{index+nPoints}

    exceeds the size of the array.

    \sa setPoint()

*/

void QPolygon::putPoints(int index, int nPoints, const int *points)

{

    if (index + nPoints > size())

        resize(index + nPoints);

    int i = index;

    while (nPoints--) {

        setPoint(i++, *points, *(points+1));

        points += 2;

    }

}

/*!

    Copies \a nPoints points from the variable argument list into this

    polygon from the given \a index.

    The points are given as a sequence of integers, starting with \a

    firstx then \a firsty, and so on. The polygon is resized if

    \c{index+nPoints} exceeds its current size.

    The example code creates a polygon with three points (4,5), (6,7)

    and (8,9), by expanding the polygon from 1 to 3 points:

    \snippet doc/src/snippets/polygon/polygon.cpp 4

    The following code has the same result, but here the putPoints()

    function overwrites rather than extends:

    \snippet doc/src/snippets/polygon/polygon.cpp 5

    \sa setPoints()

*/

void QPolygon::putPoints(int index, int nPoints, int firstx, int firsty, ...)

{

    va_list ap;

    if (index + nPoints > size())

        resize(index + nPoints);

    if (nPoints <= 0)

        return;

    setPoint(index, firstx, firsty);

    int i = index, x, y;

    va_start(ap, firsty);

    while (--nPoints) {

        x = va_arg(ap, int);

        y = va_arg(ap, int);

        setPoint(++i, x, y);

    }

    va_end(ap);

}

/*!

    \fn void QPolygon::putPoints(int index, int nPoints, const QPolygon &fromPolygon, int fromIndex)

    \overload

    Copies \a nPoints points from the given \a fromIndex ( 0 by

    default) in \a fromPolygon into this polygon, starting at the

    specified \a index. For example:

    \snippet doc/src/snippets/polygon/polygon.cpp 6

*/

void QPolygon::putPoints(int index, int nPoints, const QPolygon & from, int fromIndex)

{

    if (index + nPoints > size())

        resize(index + nPoints);

    if (nPoints <= 0)

        return;

    int n = 0;

    while(n < nPoints) {

        setPoint(index + n, from[fromIndex+n]);

        ++n;

    }

}

/*!

    Returns the bounding rectangle of the polygon, or QRect(0, 0, 0,

    0) if the polygon is empty.

    \sa QVector::isEmpty()

*/

QRect QPolygon::boundingRect() const

{

    if (isEmpty())

        return QRect(0, 0, 0, 0);

    register const QPoint *pd = constData();

    int minx, maxx, miny, maxy;

    minx = maxx = pd->x();

    miny = maxy = pd->y();

    ++pd;

    for (int i = 1; i < size(); ++i) {

        if (pd->x() < minx)

            minx = pd->x();

        else if (pd->x() > maxx)

            maxx = pd->x();

        if (pd->y() < miny)

            miny = pd->y();

        else if (pd->y() > maxy)

            maxy = pd->y();

        ++pd;

    }

    return QRect(QPoint(minx,miny), QPoint(maxx,maxy));

}

#ifndef QT_NO_DEBUG_STREAM

QDebug operator<<(QDebug dbg, const QPolygon &a)

{

#ifndef Q_BROKEN_DEBUG_STREAM

    dbg.nospace() << "QPolygon(";

    for (int i = 0; i < a.count(); ++i)

        dbg.nospace() << a.at(i);

    dbg.nospace() << ')';

    return dbg.space();

#else

    qWarning("This compiler doesn't support streaming QPolygon to QDebug");

    return dbg;

    Q_UNUSED(a);

#endif

}

#endif

/*!

    \class QPolygonF

    \brief The QPolygonF class provides a vector of points using

    floating point precision.

    \reentrant

    \ingroup painting

    \ingroup shared

    A QPolygonF is a QVector<QPointF>. The easiest way to add points

    to a QPolygonF is to use its streaming operator, as illustrated

    below:

    \snippet doc/src/snippets/polygon/polygon.cpp 1

    In addition to the functions provided by QVector, QPolygonF

    provides the boundingRect() and translate() functions for geometry

    operations. Use the QMatrix::map() function for more general

    transformations of QPolygonFs.

    QPolygonF also provides the isClosed() function to determine

    whether a polygon's start and end points are the same, and the

    toPolygon() function returning an integer precision copy of this

    polygon.

    The QPolygonF class is \l {Implicit Data Sharing}{implicitly

    shared}.

    \sa QVector, QPolygon, QLineF

*/

/*****************************************************************************

  QPolygonF member functions

 *****************************************************************************/

/*!

    \fn QPolygonF::QPolygonF()

    Constructs a polygon with no points.

    \sa QVector::isEmpty()

*/