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 **
 ** Copyright (C) 2015 The Qt Company Ltd.
 ** Contact: http://www.qt.io/licensing/
 **
 ** This file is part of the QtLocation module of the Qt Toolkit.
 **
 ** $QT_BEGIN_LICENSE:LGPL3$
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 ** accordance with the commercial license agreement provided with the
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 ** Alternatively, this file may be used under the terms of the GNU Lesser
 ** General Public License version 3 as published by the Free Software
 ** Foundation and appearing in the file LICENSE.LGPLv3 included in the
 ** packaging of this file. Please review the following information to
 ** ensure the GNU Lesser General Public License version 3 requirements
 ** will be met: https://www.gnu.org/licenses/lgpl.html.
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 ** Alternatively, this file may be used under the terms of the GNU
 ** General Public License version 2.0 or later as published by the Free
 ** Software Foundation and appearing in the file LICENSE.GPL included in
 ** the packaging of this file. Please review the following information to
 ** ensure the GNU General Public License version 2.0 requirements will be
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 ****************************************************************************/

#include "qdeclarativepolylinemapitem_p.h"
#include "qlocationutils_p.h"
#include "error_messages_p.h"
#include "locationvaluetypehelper_p.h"
#include "qdoublevector2d_p.h"
#include <QtLocation/private/qgeomap_p.h>

#include <QtCore/QScopedValueRollback>
#include <QtQml/QQmlInfo>
#include <QtQml/private/qqmlengine_p.h>
#include <QPainter>
#include <QPainterPath>
#include <QPainterPathStroker>
#include <qnumeric.h>

#include <QtGui/private/qvectorpath_p.h>
#include <QtGui/private/qtriangulatingstroker_p.h>
#include <QtGui/private/qtriangulator_p.h>

#include <QtPositioning/private/qclipperutils_p.h>
#include <QtPositioning/private/qgeopath_p.h>
#include <array>

QT_BEGIN_NAMESPACE


static const double kClipperScaleFactor = 281474976710656.0;  // 48 bits of precision

static inline IntPoint toIntPoint(const double x, const double y)
{
    return IntPoint(cInt(x * kClipperScaleFactor), cInt(y * kClipperScaleFactor));
}

static IntPoint toIntPoint(const QDoubleVector2D &p)
{
    return toIntPoint(p.x(), p.y());
}

static bool get_line_intersection(const double p0_x,
                                 const double p0_y,
                                 const double p1_x,
                                 const double p1_y,
                                 const double p2_x,
                                 const double p2_y,
                                 const double p3_x,
                                 const double p3_y,
                                 double *i_x,
                                 double *i_y,
                                 double *i_t)
{
    const double s10_x = p1_x - p0_x;
    const double s10_y = p1_y - p0_y;
    const double s32_x = p3_x - p2_x;
    const double s32_y = p3_y - p2_y;

    const double denom = s10_x * s32_y - s32_x * s10_y;
    if (denom == 0.0)
        return false; // Collinear
    const bool denomPositive = denom > 0;

    const double s02_x = p0_x - p2_x;
    const double s02_y = p0_y - p2_y;
    const double s_numer = s10_x * s02_y - s10_y * s02_x;
    if ((s_numer < 0.0) == denomPositive)
        return false; // No collision

    const double t_numer = s32_x * s02_y - s32_y * s02_x;
    if ((t_numer < 0.0) == denomPositive)
        return false; // No collision

    if (((s_numer > denom) == denomPositive) || ((t_numer > denom) == denomPositive))
        return false; // No collision
    // Collision detected
    *i_t = t_numer / denom;
    *i_x = p0_x + (*i_t * s10_x);
    *i_y = p0_y + (*i_t * s10_y);

    return true;
}

enum SegmentType {
    NoIntersection,
    OneIntersection,
    TwoIntersections
};

static QList<QList<QDoubleVector2D> > clipLine(
        const QList<QDoubleVector2D> &l,
        const QList<QDoubleVector2D> &poly)
{
    QList<QList<QDoubleVector2D> > res;
    if (poly.size() < 3 || l.size() < 2)
        return res;

    // Step 1: build edges
    std::vector<std::array<double, 4> > edges;
    for (int i = 1; i < poly.size(); i++)
        edges.push_back({ { poly.at(i-1).x(), poly.at(i-1).y(), poly.at(i).x(), poly.at(i).y() } });
    edges.push_back({ { poly.at(poly.size()-1).x(), poly.at(poly.size()-1).y(), poly.at(0).x(), poly.at(0).y() } });

    // Build Path to check for containment, for edges not intersecting
    // This step could be speeded up by forcing the orientation of the polygon, and testing the cross products in the step
    // below, thus avoiding to resort to clipper.
    Path clip;
    for (const auto &v: poly)
        clip.push_back(toIntPoint(v));

    // Step 2: check each segment against each edge
    QList<QDoubleVector2D> subLine;
    std::array<double, 4> intersections = { { 0.0, 0.0, 0.0, 0.0 } };

    for (int i = 0; i < l.size() - 1; ++i) {
        SegmentType type = NoIntersection;
        double t = -1; // valid values are in [0, 1]. Only written if intersects
        double previousT = t;
        double i_x, i_y;

        const int firstContained = c2t::clip2tri::pointInPolygon(toIntPoint(l.at(i).x(), l.at(i).y()), clip);
        const int secondContained = c2t::clip2tri::pointInPolygon(toIntPoint(l.at(i+1).x(), l.at(i+1).y()), clip);

        if (firstContained && secondContained) { // Second most common condition, test early and skip inner loop if possible
            if (!subLine.size())
                subLine.push_back(l.at(i)); // the initial element has to be pushed now.
            subLine.push_back(l.at(i+1));
            continue;
        }

        for (unsigned int j = 0; j < edges.size(); ++j) {
            const bool intersects = get_line_intersection(l.at(i).x(),
                                                         l.at(i).y(),
                                                         l.at(i+1).x(),
                                                         l.at(i+1).y(),
                                                         edges.at(j).at(0),
                                                         edges.at(j).at(1),
                                                         edges.at(j).at(2),
                                                         edges.at(j).at(3),
                                                         &i_x,
                                                         &i_y,
                                                         &t);
            if (intersects) {
                if (previousT >= 0.0) { //One intersection already hit
                    if (t < previousT) { // Reorder
                        intersections[2] = intersections[0];
                        intersections[3] = intersections[1];
                        intersections[0] = i_x;
                        intersections[1] = i_y;
                    } else {
                        intersections[2] = i_x;
                        intersections[3] = i_y;
                    }

                    type = TwoIntersections;
                    break; // no need to check anything else
                } else { // First intersection
                    intersections[0] = i_x;
                    intersections[1] = i_y;
                    type = OneIntersection;
                }
                previousT = t;
            }
        }

        if (type == NoIntersection) {
            if (!firstContained && !secondContained) { // Both outside
                subLine.clear();
            } else if (firstContained && secondContained) {
                // Handled above already.
            } else { // Mismatch between PointInPolygon and get_line_intersection. Treat it as no intersection
                if (subLine.size())
                    res.push_back(subLine);
                subLine.clear();
            }
        } else if (type == OneIntersection) { // Need to check the following cases to avoid mismatch with PointInPolygon result.
            if (firstContained <= 0 && secondContained > 0) { // subLine MUST be empty
                if (!subLine.size())
                    subLine.push_back(QDoubleVector2D(intersections[0], intersections[1]));
                subLine.push_back(l.at(i+1));
            } else if (firstContained > 0 && secondContained <= 0) { // subLine MUST NOT be empty
                if (!subLine.size())
                    subLine.push_back(l.at(i));
                subLine.push_back(QDoubleVector2D(intersections[0], intersections[1]));
                res.push_back(subLine);
                subLine.clear();
            } else {
                if (subLine.size())
                    res.push_back(subLine);
                subLine.clear();
            }
        } else { // Two
            // restart strip
            subLine.clear();
            subLine.push_back(QDoubleVector2D(intersections[0], intersections[1]));
            subLine.push_back(QDoubleVector2D(intersections[2], intersections[3]));
            res.push_back(subLine);
            subLine.clear();
        }
    }

    if (subLine.size())
        res.push_back(subLine);
    return res;
}

/*!
    \qmltype MapPolyline
    \instantiates QDeclarativePolylineMapItem
    \inqmlmodule QtLocation
    \ingroup qml-QtLocation5-maps
    \since QtLocation 5.0

    \brief The MapPolyline type displays a polyline on a map.

    The MapPolyline type displays a polyline on a map, specified in terms of an ordered list of
    \l {coordinate}{coordinates}.  The \l {coordinate}{coordinates} on
    the path cannot be directly changed after being added to the Polyline.  Instead, copy the
    \l path into a var, modify the copy and reassign the copy back to the \l path.

    \code
    var path = mapPolyline.path;
    path[0].latitude = 5;
    mapPolyline.path = path;
    \endcode

    Coordinates can also be added and removed at any time using the \l addCoordinate and
    \l removeCoordinate methods.

    By default, the polyline is displayed as a 1-pixel thick black line. This
    can be changed using the \l line.width and \l line.color properties.

    \section2 Performance

    MapPolylines have a rendering cost that is O(n) with respect to the number
    of vertices. This means that the per frame cost of having a polyline on
    the Map grows in direct proportion to the number of points in the polyline.

    Like the other map objects, MapPolyline is normally drawn without a smooth
    appearance. Setting the \l {Item::opacity}{opacity} property will force the object to
    be blended, which decreases performance considerably depending on the hardware in use.

    \section2 Example Usage

    The following snippet shows a MapPolyline with 4 points, making a shape
    like the top part of a "question mark" (?), near Brisbane, Australia.
    The line drawn is 3 pixels in width and green in color.

    \code
    Map {
        MapPolyline {
            line.width: 3
            line.color: 'green'
            path: [
                { latitude: -27, longitude: 153.0 },
                { latitude: -27, longitude: 154.1 },
                { latitude: -28, longitude: 153.5 },
                { latitude: -29, longitude: 153.5 }
            ]
        }
    }
    \endcode

    \image api-mappolyline.png
*/

QDeclarativeMapLineProperties::QDeclarativeMapLineProperties(QObject *parent) :
    QObject(parent),
    width_(1.0),
    color_(Qt::black)
{
}

/*!
    \internal
*/
QColor QDeclarativeMapLineProperties::color() const
{
    return color_;
}

/*!
    \internal
*/
void QDeclarativeMapLineProperties::setColor(const QColor &color)
{
    if (color_ == color)
        return;

    color_ = color;
    emit colorChanged(color_);
}

/*!
    \internal
*/
qreal QDeclarativeMapLineProperties::width() const
{
    return width_;
}

/*!
    \internal
*/
void QDeclarativeMapLineProperties::setWidth(qreal width)
{
    if (width_ == width)
        return;

    width_ = width;
    emit widthChanged(width_);
}

struct Vertex
{
    QVector2D position;
};

QGeoMapPolylineGeometry::QGeoMapPolylineGeometry()
{
}

QList<QList<QDoubleVector2D> > QGeoMapPolylineGeometry::clipPath(const QGeoMap &map,
                                                           const QList<QDoubleVector2D> &path,
                                                           QDoubleVector2D &leftBoundWrapped)
{
    /*
     * Approach:
     * 1) project coordinates to wrapped web mercator, and do unwrapBelowX
     * 2) if the scene is tilted, clip the geometry against the visible region (this may generate multiple polygons)
     * 2.1) recalculate the origin and geoLeftBound to prevent these parameters from ending in unprojectable areas
     * 2.2) ensure the left bound does not wrap around due to QGeoCoordinate <-> clipper conversions
     */
    const QGeoProjectionWebMercator &p = static_cast<const QGeoProjectionWebMercator&>(map.geoProjection());
    srcOrigin_ = geoLeftBound_;

    double unwrapBelowX = 0;
    leftBoundWrapped = p.wrapMapProjection(p.geoToMapProjection(geoLeftBound_));
    if (preserveGeometry_)
        unwrapBelowX = leftBoundWrapped.x();

    QList<QDoubleVector2D> wrappedPath;
    wrappedPath.reserve(path.size());
    QDoubleVector2D wrappedLeftBound(qInf(), qInf());
    // 1)
    for (int i = 0; i < path.size(); ++i) {
        const QDoubleVector2D &coord = path.at(i);
        QDoubleVector2D wrappedProjection = p.wrapMapProjection(coord);

        // We can get NaN if the map isn't set up correctly, or the projection
        // is faulty -- probably best thing to do is abort
        if (!qIsFinite(wrappedProjection.x()) || !qIsFinite(wrappedProjection.y()))
            return QList<QList<QDoubleVector2D> >();

        const bool isPointLessThanUnwrapBelowX = (wrappedProjection.x() < leftBoundWrapped.x());
        // unwrap x to preserve geometry if moved to border of map
        if (preserveGeometry_ && isPointLessThanUnwrapBelowX) {
            double distance = wrappedProjection.x() - unwrapBelowX;
            if (distance < 0.0)
                distance += 1.0;
            wrappedProjection.setX(unwrapBelowX + distance);
        }
        if (wrappedProjection.x() < wrappedLeftBound.x() || (wrappedProjection.x() == wrappedLeftBound.x() && wrappedProjection.y() < wrappedLeftBound.y())) {
            wrappedLeftBound = wrappedProjection;
        }
        wrappedPath.append(wrappedProjection);
    }

#ifdef QT_LOCATION_DEBUG
    m_wrappedPath = wrappedPath;
#endif

    // 2)
    QList<QList<QDoubleVector2D> > clippedPaths;
    const QList<QDoubleVector2D> &visibleRegion = p.projectableGeometry();
    if (visibleRegion.size()) {
        clippedPaths = clipLine(wrappedPath, visibleRegion);

        // 2.1) update srcOrigin_ and leftBoundWrapped with the point with minimum X
        QDoubleVector2D lb(qInf(), qInf());
        for (const QList<QDoubleVector2D> &path: clippedPaths) {
            for (const QDoubleVector2D &p: path) {
                if (p == leftBoundWrapped) {
                    lb = p;
                    break;
                } else if (p.x() < lb.x() || (p.x() == lb.x() && p.y() < lb.y())) {
                    // y-minimization needed to find the same point on polygon and border
                    lb = p;
                }
            }
        }
        if (qIsInf(lb.x()))
            return QList<QList<QDoubleVector2D> >();

        // 2.2) Prevent the conversion to and from clipper from introducing negative offsets which
        //      in turn will make the geometry wrap around.
        lb.setX(qMax(wrappedLeftBound.x(), lb.x()));
        leftBoundWrapped = lb;
    } else {
        clippedPaths.append(wrappedPath);
    }

#ifdef QT_LOCATION_DEBUG
    m_clippedPaths = clippedPaths;
#endif

    return clippedPaths;
}

void QGeoMapPolylineGeometry::pathToScreen(const QGeoMap &map,
                                           const QList<QList<QDoubleVector2D> > &clippedPaths,
                                           const QDoubleVector2D &leftBoundWrapped)
{
    const QGeoProjectionWebMercator &p = static_cast<const QGeoProjectionWebMercator&>(map.geoProjection());
    // 3) project the resulting geometry to screen position and calculate screen bounds
    double minX = qInf();
    double minY = qInf();
    double maxX = -qInf();
    double maxY = -qInf();
    srcOrigin_ = p.mapProjectionToGeo(p.unwrapMapProjection(leftBoundWrapped));
    QDoubleVector2D origin = p.wrappedMapProjectionToItemPosition(leftBoundWrapped);
    for (const QList<QDoubleVector2D> &path: clippedPaths) {
        QDoubleVector2D lastAddedPoint;
        for (int i = 0; i < path.size(); ++i) {
            QDoubleVector2D point = p.wrappedMapProjectionToItemPosition(path.at(i));
            point = point - origin; // (0,0) if point == geoLeftBound_

            minX = qMin(point.x(), minX);
            minY = qMin(point.y(), minY);
            maxX = qMax(point.x(), maxX);
            maxY = qMax(point.y(), maxY);

            if (i == 0) {
                srcPoints_ << point.x() << point.y();
                srcPointTypes_ << QPainterPath::MoveToElement;
                lastAddedPoint = point;
            } else {
                if ((point - lastAddedPoint).manhattanLength() > 3 ||
                        i == path.size() - 1) {
                    srcPoints_ << point.x() << point.y();
                    srcPointTypes_ << QPainterPath::LineToElement;
                    lastAddedPoint = point;
                }
            }
        }
    }

    sourceBounds_ = QRectF(QPointF(minX, minY), QPointF(maxX, maxY));
}

/*!
    \internal
*/
void QGeoMapPolylineGeometry::updateSourcePoints(const QGeoMap &map,
                                                 const QList<QDoubleVector2D> &path,
                                                 const QGeoCoordinate geoLeftBound)
{
    if (!sourceDirty_)
        return;

    geoLeftBound_ = geoLeftBound;

    // clear the old data and reserve enough memory
    srcPoints_.clear();
    srcPoints_.reserve(path.size() * 2);
    srcPointTypes_.clear();
    srcPointTypes_.reserve(path.size());

    /*
     * Approach:
     * 1) project coordinates to wrapped web mercator, and do unwrapBelowX
     * 2) if the scene is tilted, clip the geometry against the visible region (this may generate multiple polygons)
     * 3) project the resulting geometry to screen position and calculate screen bounds
     */

    QDoubleVector2D leftBoundWrapped;
    // 1, 2)
    const QList<QList<QDoubleVector2D> > &clippedPaths = clipPath(map, path, leftBoundWrapped);

    // 3)
    pathToScreen(map, clippedPaths, leftBoundWrapped);
}

// ***  SCREEN CLIPPING *** //

enum ClipPointType {
    InsidePoint  = 0x00,
    LeftPoint    = 0x01,
    RightPoint   = 0x02,
    BottomPoint  = 0x04,
    TopPoint     = 0x08
};

static inline int clipPointType(qreal x, qreal y, const QRectF &rect)
{
    int type = InsidePoint;
    if (x < rect.left())
        type |= LeftPoint;
    else if (x > rect.right())
        type |= RightPoint;
    if (y < rect.top())
        type |= TopPoint;
    else if (y > rect.bottom())
        type |= BottomPoint;
    return type;
}

static void clipSegmentToRect(qreal x0, qreal y0, qreal x1, qreal y1,
                              const QRectF &clipRect,
                              QVector<qreal> &outPoints,
                              QVector<QPainterPath::ElementType> &outTypes)
{
    int type0 = clipPointType(x0, y0, clipRect);
    int type1 = clipPointType(x1, y1, clipRect);
    bool accept = false;

    while (true) {
        if (!(type0 | type1)) {
            accept = true;
            break;
        } else if (type0 & type1) {
            break;
        } else {
            qreal x = 0.0;
            qreal y = 0.0;
            int outsideType = type0 ? type0 : type1;

            if (outsideType & BottomPoint) {
                x = x0 + (x1 - x0) * (clipRect.bottom() - y0) / (y1 - y0);
                y = clipRect.bottom() - 0.1;
            } else if (outsideType & TopPoint) {
                x = x0 + (x1 - x0) * (clipRect.top() - y0) / (y1 - y0);
                y = clipRect.top() + 0.1;
            } else if (outsideType & RightPoint) {
                y = y0 + (y1 - y0) * (clipRect.right() - x0) / (x1 - x0);
                x = clipRect.right() - 0.1;
            } else if (outsideType & LeftPoint) {
                y = y0 + (y1 - y0) * (clipRect.left() - x0) / (x1 - x0);
                x = clipRect.left() + 0.1;
            }

            if (outsideType == type0) {
                x0 = x;
                y0 = y;
                type0 = clipPointType(x0, y0, clipRect);
            } else {
                x1 = x;
                y1 = y;
                type1 = clipPointType(x1, y1, clipRect);
            }
        }
    }

    if (accept) {
        if (outPoints.size() >= 2) {
            qreal lastX, lastY;
            lastY = outPoints.at(outPoints.size() - 1);
            lastX = outPoints.at(outPoints.size() - 2);

            if (!qFuzzyCompare(lastY, y0) || !qFuzzyCompare(lastX, x0)) {
                outTypes << QPainterPath::MoveToElement;
                outPoints << x0 << y0;
            }
        } else {
            outTypes << QPainterPath::MoveToElement;
            outPoints << x0 << y0;
        }

        outTypes << QPainterPath::LineToElement;
        outPoints << x1 << y1;
    }
}

static void clipPathToRect(const QVector<qreal> &points,
                           const QVector<QPainterPath::ElementType> &types,
                           const QRectF &clipRect,
                           QVector<qreal> &outPoints,
                           QVector<QPainterPath::ElementType> &outTypes)
{
    outPoints.clear();
    outPoints.reserve(points.size());
    outTypes.clear();
    outTypes.reserve(types.size());

    qreal lastX = 0;
    qreal lastY = 0; // or else used uninitialized
    for (int i = 0; i < types.size(); ++i) {
        if (i > 0 && types[i] != QPainterPath::MoveToElement) {
            qreal x = points[i * 2], y = points[i * 2 + 1];
            clipSegmentToRect(lastX, lastY, x, y, clipRect, outPoints, outTypes);
        }

        lastX = points[i * 2];
        lastY = points[i * 2 + 1];
    }
}

////////////////////////////////////////////////////////////////////////////

/*!
    \internal
*/
void QGeoMapPolylineGeometry::updateScreenPoints(const QGeoMap &map,
                                                 qreal strokeWidth,
                                                 bool adjustTranslation)
{
    if (!screenDirty_)
        return;

    QPointF origin = map.geoProjection().coordinateToItemPosition(srcOrigin_, false).toPointF();

    if (!qIsFinite(origin.x()) || !qIsFinite(origin.y()) || srcPointTypes_.size() < 2) { // the line might have been clipped away.
        clear();
        return;
    }

    // Create the viewport rect in the same coordinate system
    // as the actual points
    QRectF viewport(0, 0, map.viewportWidth(), map.viewportHeight());
    viewport.adjust(-strokeWidth, -strokeWidth, strokeWidth, strokeWidth);
    viewport.translate(-1 * origin);

    QVector<qreal> points;
    QVector<QPainterPath::ElementType> types;

    if (clipToViewport_) {
        // Although the geometry has already been clipped against the visible region in wrapped mercator space.
        // This is currently still needed to prevent a number of artifacts deriving from QTriangulatingStroker processing
        // very large lines (that is, polylines that span many pixels in screen space)
        clipPathToRect(srcPoints_, srcPointTypes_, viewport, points, types);
    } else {
        points = srcPoints_;
        types = srcPointTypes_;
    }

    QVectorPath vp(points.data(), types.size(), types.data());
    QTriangulatingStroker ts;
    // As of Qt5.11, the clip argument is not actually used, in the call below.
    ts.process(vp, QPen(QBrush(Qt::black), strokeWidth), QRectF(), QPainter::Qt4CompatiblePainting);

    clear();

    // Nothing is on the screen
    if (ts.vertexCount() == 0)
        return;

    // QTriangulatingStroker#vertexCount is actually the length of the array,
    // not the number of vertices
    screenVertices_.reserve(ts.vertexCount());

    QRectF bb;

    QPointF pt;
    const float *vs = ts.vertices();
    for (int i = 0; i < (ts.vertexCount()/2*2); i += 2) {
        pt = QPointF(vs[i], vs[i + 1]);
        screenVertices_ << pt;

        if (!qIsFinite(pt.x()) || !qIsFinite(pt.y()))
            break;

        if (!bb.contains(pt)) {
            if (pt.x() < bb.left())
                bb.setLeft(pt.x());

            if (pt.x() > bb.right())
                bb.setRight(pt.x());

            if (pt.y() < bb.top())
                bb.setTop(pt.y());

            if (pt.y() > bb.bottom())
                bb.setBottom(pt.y());
        }
    }

    screenBounds_ = bb;
    const QPointF strokeOffset = (adjustTranslation) ? QPointF(strokeWidth, strokeWidth) : QPointF();
    this->translate( -1 * sourceBounds_.topLeft() + strokeOffset);
}

void QGeoMapPolylineGeometry::clearSource()
{
    srcPoints_.clear();
    srcPointTypes_.clear();
}

bool QGeoMapPolylineGeometry::contains(const QPointF &point) const
{
    // screenOutline_.contains(screenPoint) doesn't work, as, it appears, that
    // screenOutline_ for QGeoMapPolylineGeometry is empty (QRectF(0,0 0x0))
    const QVector<QPointF> &verts = vertices();
    QPolygonF tri;
    for (int i = 0; i < verts.size(); ++i) {
        tri << verts[i];
        if (tri.size() == 3) {
            if (tri.containsPoint(point,Qt::OddEvenFill))
                return true;
            tri.remove(0);
        }
    }

    return false;
}

QDeclarativePolylineMapItem::QDeclarativePolylineMapItem(QQuickItem *parent)
:   QDeclarativeGeoMapItemBase(parent), line_(this), dirtyMaterial_(true), updatingGeometry_(false)
{
    m_itemType = QGeoMap::MapPolyline;
    geopath_ = QGeoPathEager();
    setFlag(ItemHasContents, true);
    QObject::connect(&line_, SIGNAL(colorChanged(QColor)),
                     this, SLOT(updateAfterLinePropertiesChanged()));
    QObject::connect(&line_, SIGNAL(widthChanged(qreal)),
                     this, SLOT(updateAfterLinePropertiesChanged()));
}

QDeclarativePolylineMapItem::~QDeclarativePolylineMapItem()
{
}

/*!
    \internal
*/
void QDeclarativePolylineMapItem::updateAfterLinePropertiesChanged()
{
    // mark dirty just in case we're a width change
    geometry_.markSourceDirty();
    polishAndUpdate();
}

/*!
    \internal
*/
void QDeclarativePolylineMapItem::setMap(QDeclarativeGeoMap *quickMap, QGeoMap *map)
{
    QDeclarativeGeoMapItemBase::setMap(quickMap,map);
    if (map) {
        regenerateCache();
        geometry_.markSourceDirty();
        polishAndUpdate();
    }
}

/*!
    \qmlproperty list<coordinate> MapPolyline::path

    This property holds the ordered list of coordinates which
    define the polyline.
*/

QJSValue QDeclarativePolylineMapItem::path() const
{
    return fromList(this, geopath_.path());
}

void QDeclarativePolylineMapItem::setPath(const QJSValue &value)
{
    if (!value.isArray())
        return;

    setPathFromGeoList(toList(this, value));
}

/*!
    \qmlmethod int MapPolyline::setPath(geopath path)

    Sets the \a path using a geopath type.

    \since 5.10

    \sa path
*/
void QDeclarativePolylineMapItem::setPath(const QGeoPath &path)
{
    if (geopath_.path() == path.path())
        return;

    geopath_ = QGeoPathEager(path);
    regenerateCache();
    geometry_.setPreserveGeometry(true, geopath_.boundingGeoRectangle().topLeft());
    markSourceDirtyAndUpdate();
    emit pathChanged();
}

/*!
    \internal
*/
void QDeclarativePolylineMapItem::setPathFromGeoList(const QList<QGeoCoordinate> &path)
{
    if (geopath_.path() == path)
        return;

    geopath_.setPath(path);

    regenerateCache();
    geometry_.setPreserveGeometry(true, geopath_.boundingGeoRectangle().topLeft());
    markSourceDirtyAndUpdate();
    emit pathChanged();
}

/*!
    \qmlmethod int MapPolyline::pathLength()

    Returns the number of coordinates of the polyline.

    \since QtLocation 5.6

    \sa path
*/
int QDeclarativePolylineMapItem::pathLength() const
{
    return geopath_.path().length();
}

/*!
    \qmlmethod void MapPolyline::addCoordinate(coordinate)

    Adds the specified \a coordinate to the end of the path.

    \sa insertCoordinate, removeCoordinate, path
*/
void QDeclarativePolylineMapItem::addCoordinate(const QGeoCoordinate &coordinate)
{
    if (!coordinate.isValid())
        return;

    geopath_.addCoordinate(coordinate);

    updateCache();
    geometry_.setPreserveGeometry(true, geopath_.boundingGeoRectangle().topLeft());
    markSourceDirtyAndUpdate();
    emit pathChanged();
}

/*!
    \qmlmethod void MapPolyline::insertCoordinate(index, coordinate)

    Inserts a \a coordinate to the path at the given \a index.

    \since QtLocation 5.6

    \sa addCoordinate, removeCoordinate, path
*/
void QDeclarativePolylineMapItem::insertCoordinate(int index, const QGeoCoordinate &coordinate)
{
    if (index < 0 || index > geopath_.path().length())
        return;

    geopath_.insertCoordinate(index, coordinate);

    regenerateCache();
    geometry_.setPreserveGeometry(true, geopath_.boundingGeoRectangle().topLeft());
    markSourceDirtyAndUpdate();
    emit pathChanged();
}

/*!
    \qmlmethod void MapPolyline::replaceCoordinate(index, coordinate)

    Replaces the coordinate in the current path at the given \a index
    with the new \a coordinate.

    \since QtLocation 5.6

    \sa addCoordinate, insertCoordinate, removeCoordinate, path
*/
void QDeclarativePolylineMapItem::replaceCoordinate(int index, const QGeoCoordinate &coordinate)
{
    if (index < 0 || index >= geopath_.path().length())
        return;

    geopath_.replaceCoordinate(index, coordinate);

    regenerateCache();
    geometry_.setPreserveGeometry(true, geopath_.boundingGeoRectangle().topLeft());
    markSourceDirtyAndUpdate();
    emit pathChanged();
}

/*!
    \qmlmethod coordinate MapPolyline::coordinateAt(index)

    Gets the coordinate of the polyline at the given \a index.
    If the index is outside the path's bounds then an invalid
    coordinate is returned.

    \since QtLocation 5.6
*/
QGeoCoordinate QDeclarativePolylineMapItem::coordinateAt(int index) const
{
    if (index < 0 || index >= geopath_.path().length())
        return QGeoCoordinate();

    return geopath_.coordinateAt(index);
}

/*!
    \qmlmethod coordinate MapPolyline::containsCoordinate(coordinate)

    Returns true if the given \a coordinate is part of the path.

    \since QtLocation 5.6
*/
bool QDeclarativePolylineMapItem::containsCoordinate(const QGeoCoordinate &coordinate)
{
    return geopath_.containsCoordinate(coordinate);
}

/*!
    \qmlmethod void MapPolyline::removeCoordinate(coordinate)

    Removes \a coordinate from the path. If there are multiple instances of the
    same coordinate, the one added last is removed.

    If \a coordinate is not in the path this method does nothing.

    \sa addCoordinate, insertCoordinate, path
*/
void QDeclarativePolylineMapItem::removeCoordinate(const QGeoCoordinate &coordinate)
{
    int length = geopath_.path().length();
    geopath_.removeCoordinate(coordinate);
    if (geopath_.path().length() == length)
        return;

    regenerateCache();
    markSourceDirtyAndUpdate();
    emit pathChanged();
}

/*!
    \qmlmethod void MapPolyline::removeCoordinate(index)

    Removes a coordinate from the path at the given \a index.

    If \a index is invalid then this method does nothing.

    \since QtLocation 5.6

    \sa addCoordinate, insertCoordinate, path
*/
void QDeclarativePolylineMapItem::removeCoordinate(int index)
{
    if (index < 0 || index >= geopath_.path().length())
        return;

    geopath_.removeCoordinate(index);

    regenerateCache();
    geometry_.setPreserveGeometry(true, geopath_.boundingGeoRectangle().topLeft());
    markSourceDirtyAndUpdate();
    emit pathChanged();
}

/*!
    \qmlpropertygroup Location::MapPolyline::line
    \qmlproperty int MapPolyline::line.width
    \qmlproperty color MapPolyline::line.color

    This property is part of the line property group. The line
    property group holds the width and color used to draw the line.

    The width is in pixels and is independent of the zoom level of the map.
    The default values correspond to a black border with a width of 1 pixel.

    For no line, use a width of 0 or a transparent color.
*/

QDeclarativeMapLineProperties *QDeclarativePolylineMapItem::line()
{
    return &line_;
}

/*!
    \internal
*/
void QDeclarativePolylineMapItem::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
{
    if (!map() || !geopath_.isValid() || updatingGeometry_ || newGeometry.topLeft() == oldGeometry.topLeft()) {
        QDeclarativeGeoMapItemBase::geometryChanged(newGeometry, oldGeometry);
        return;
    }
    // TODO: change the algorithm to preserve the distances and size!
    QGeoCoordinate newCenter = map()->geoProjection().itemPositionToCoordinate(QDoubleVector2D(newGeometry.center()), false);
    QGeoCoordinate oldCenter = map()->geoProjection().itemPositionToCoordinate(QDoubleVector2D(oldGeometry.center()), false);
    if (!newCenter.isValid() || !oldCenter.isValid())
        return;
    double offsetLongi = newCenter.longitude() - oldCenter.longitude();
    double offsetLati = newCenter.latitude() - oldCenter.latitude();
    if (offsetLati == 0.0 && offsetLongi == 0.0)
        return;

    geopath_.translate(offsetLati, offsetLongi);
    regenerateCache();
    geometry_.setPreserveGeometry(true, geopath_.boundingGeoRectangle().topLeft());
    markSourceDirtyAndUpdate();
    emit pathChanged();

    // Not calling QDeclarativeGeoMapItemBase::geometryChanged() as it will be called from a nested
    // call to this function.
}

/*!
    \internal
*/
void QDeclarativePolylineMapItem::afterViewportChanged(const QGeoMapViewportChangeEvent &event)
{
    if (event.mapSize.width() <= 0 || event.mapSize.height() <= 0)
        return;

    geometry_.setPreserveGeometry(true, geometry_.geoLeftBound());
    markSourceDirtyAndUpdate();
}

/*!
    \internal
*/
void QDeclarativePolylineMapItem::regenerateCache()
{
    if (!map() || map()->geoProjection().projectionType() != QGeoProjection::ProjectionWebMercator)
        return;
    const QGeoProjectionWebMercator &p = static_cast<const QGeoProjectionWebMercator&>(map()->geoProjection());
    geopathProjected_.clear();
    geopathProjected_.reserve(geopath_.path().size());
    for (const QGeoCoordinate &c : geopath_.path())
        geopathProjected_ << p.geoToMapProjection(c);
}

/*!
    \internal
*/
void QDeclarativePolylineMapItem::updateCache()
{
    if (!map() ||  map()->geoProjection().projectionType() != QGeoProjection::ProjectionWebMercator)
        return;
    const QGeoProjectionWebMercator &p = static_cast<const QGeoProjectionWebMercator&>(map()->geoProjection());
    geopathProjected_ << p.geoToMapProjection(geopath_.path().last());
}

/*!
    \internal
*/
void QDeclarativePolylineMapItem::updatePolish()
{
    if (!map() || map()->geoProjection().projectionType() != QGeoProjection::ProjectionWebMercator)
        return;
    if (geopath_.path().length() == 0) { // Possibly cleared
        geometry_.clear();
        setWidth(0);
        setHeight(0);
        return;
    }

    QScopedValueRollback<bool> rollback(updatingGeometry_);
    updatingGeometry_ = true;

    geometry_.updateSourcePoints(*map(), geopathProjected_, geopath_.boundingGeoRectangle().topLeft());
    geometry_.updateScreenPoints(*map(), line_.width());

    setWidth(geometry_.sourceBoundingBox().width() + 2 * line_.width());
    setHeight(geometry_.sourceBoundingBox().height() + 2 * line_.width());

    setPositionOnMap(geometry_.origin(), -1 * geometry_.sourceBoundingBox().topLeft() + QPointF(line_.width(), line_.width()));
}

void QDeclarativePolylineMapItem::markSourceDirtyAndUpdate()
{
    geometry_.markSourceDirty();
    polishAndUpdate();
}

/*!
    \internal
*/
QSGNode *QDeclarativePolylineMapItem::updateMapItemPaintNode(QSGNode *oldNode, UpdatePaintNodeData *data)
{
    Q_UNUSED(data);

    MapPolylineNode *node = static_cast<MapPolylineNode *>(oldNode);

    if (!node) {
        node = new MapPolylineNode();
    }

    //TODO: update only material
    if (geometry_.isScreenDirty() || dirtyMaterial_ || !oldNode) {
        node->update(line_.color(), &geometry_);
        geometry_.setPreserveGeometry(false);
        geometry_.markClean();
        dirtyMaterial_ = false;
    }
    return node;
}

bool QDeclarativePolylineMapItem::contains(const QPointF &point) const
{
    return geometry_.contains(point);
}

const QGeoShape &QDeclarativePolylineMapItem::geoShape() const
{
    return geopath_;
}

void QDeclarativePolylineMapItem::setGeoShape(const QGeoShape &shape)
{
    const QGeoPath geopath(shape); // if shape isn't a path, path will be created as a default-constructed path
    setPath(geopath);
}

//////////////////////////////////////////////////////////////////////

/*!
    \internal
*/
VisibleNode::VisibleNode() : m_blocked{true}, m_visible{true}
{

}

VisibleNode::~VisibleNode()
{

}

/*!
    \internal
*/
bool VisibleNode::subtreeBlocked() const
{
    return m_blocked || !m_visible;
}

/*!
    \internal
*/
void VisibleNode::setSubtreeBlocked(bool blocked)
{
    m_blocked = blocked;
}

bool VisibleNode::visible() const
{
    return m_visible;
}

/*!
    \internal
*/
void VisibleNode::setVisible(bool visible)
{
    m_visible = visible;
}

/*!
    \internal
*/
MapItemGeometryNode::~MapItemGeometryNode()
{

}

bool MapItemGeometryNode::isSubtreeBlocked() const
{
    return subtreeBlocked();
}


/*!
    \internal
*/
MapPolylineNode::MapPolylineNode() :
    geometry_(QSGGeometry::defaultAttributes_Point2D(),0)
{
    geometry_.setDrawingMode(QSGGeometry::DrawTriangleStrip);
    QSGGeometryNode::setMaterial(&fill_material_);
    QSGGeometryNode::setGeometry(&geometry_);
}


/*!
    \internal
*/
MapPolylineNode::~MapPolylineNode()
{
}

/*!
    \internal
*/
void MapPolylineNode::update(const QColor &fillColor,
                             const QGeoMapItemGeometry *shape)
{
    if (shape->size() == 0) {
        setSubtreeBlocked(true);
        return;
    } else {
        setSubtreeBlocked(false);
    }

    QSGGeometry *fill = QSGGeometryNode::geometry();
    shape->allocateAndFill(fill);
    markDirty(DirtyGeometry);

    if (fillColor != fill_material_.color()) {
        fill_material_.setColor(fillColor);
        setMaterial(&fill_material_);
        markDirty(DirtyMaterial);
    }
}

QT_END_NAMESPACE
