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

**

** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

** All rights reserved.

** Contact: Nokia Corporation (qt-info@nokia.com)

**

** This file is part of the QtGui module of the Qt Toolkit.

**

** $QT_BEGIN_LICENSE:LGPL$

** No Commercial Usage

** This file contains pre-release code and may not be distributed.

** You may use this file in accordance with the terms and conditions

** contained in the Technology Preview License Agreement accompanying

** this package.

**

** GNU Lesser General Public License Usage

** Alternatively, this file may be used under the terms of the GNU Lesser

** General Public License version 2.1 as published by the Free Software

** Foundation and appearing in the file LICENSE.LGPL included in the

** packaging of this file.  Please review the following information to

** ensure the GNU Lesser General Public License version 2.1 requirements

** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.

**

** In addition, as a special exception, Nokia gives you certain additional

** rights.  These rights are described in the Nokia Qt LGPL Exception

** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.

**

** If you have questions regarding the use of this file, please contact

** Nokia at qt-info@nokia.com.

**

**

**

**

**

**

**

**

** $QT_END_LICENSE$

**

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

#ifndef QPATHCLIPPER_P_H

#define QPATHCLIPPER_P_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  It exists purely as an

// implementation detail.  This header file may change from version to

// version without notice, or even be removed.

//

// We mean it.

//

#include <QtGui/qpainterpath.h>

#include <QtCore/qlist.h>

#include <private/qbezier_p.h>

#include <private/qdatabuffer_p.h>

#include <stdio.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

QT_MODULE(Gui)

class QWingedEdge;

class Q_AUTOTEST_EXPORT QPathClipper

{

public:

    enum Operation {

        BoolAnd,

        BoolOr,

        BoolSub,

        Simplify

    };

public:

    QPathClipper(const QPainterPath &subject,

                 const QPainterPath &clip);

    QPainterPath clip(Operation op = BoolAnd);

    bool intersect();

    bool contains();

private:

    Q_DISABLE_COPY(QPathClipper)

    enum ClipperMode {

        ClipMode, // do the full clip

        CheckMode // for contains/intersects (only interested in whether the result path is non-empty)

    };

    bool handleCrossingEdges(QWingedEdge &list, qreal y, ClipperMode mode);

    bool doClip(QWingedEdge &list, ClipperMode mode);

    QPainterPath subjectPath;

    QPainterPath clipPath;

    Operation op;

    int aMask;

    int bMask;

};

struct QPathVertex

{

public:

    QPathVertex(const QPointF &p = QPointF(), int e = -1);

    operator QPointF() const;

    int edge;

    qreal x;

    qreal y;

};

class QPathEdge

{

public:

    enum Traversal {

        RightTraversal,

        LeftTraversal

    };

    enum Direction {

        Forward,

        Backward

    };

    enum Type {

        Line,

        Curve

    };

    QPathEdge(int a = -1, int b = -1);

    mutable int flag;

    int windingA;

    int windingB;

    int first;

    int second;

    qreal angle;

    qreal invAngle;

    const QBezier *bezier;

    qreal t0;

    qreal t1;

    int next(Traversal traversal, Direction direction) const;

    void setNext(Traversal traversal, Direction direction, int next);

    void setNext(Direction direction, int next);

    Direction directionTo(int vertex) const;

    int vertex(Direction direction) const;

private:

    int m_next[2][2];

};

class QPathSegments

{

public:

    struct Intersection {

        int vertex;

        qreal t;

        int next;

        bool operator<(const Intersection &o) const {

            return t < o.t;

        }

    };

    struct Segment {

        Segment(int pathId, int vertexA, int vertexB, int bezierIndex = -1)

            : path(pathId)

            , bezier(bezierIndex)

            , va(vertexA)

            , vb(vertexB)

            , intersection(-1)

        {

        }

        int path;

        int bezier;

        // vertices

        int va;

        int vb;

        // intersection index

        int intersection;

        QRectF bounds;

    };

    QPathSegments();

    void setPath(const QPainterPath &path);

    void addPath(const QPainterPath &path);

    int intersections() const;

    int segments() const;

    int points() const;

    const Segment &segmentAt(int index) const;

    const QLineF lineAt(int index) const;

    const QBezier *bezierAt(int index) const;

    const QRectF &elementBounds(int index) const;

    int pathId(int index) const;

    const QPointF &pointAt(int vertex) const;

    int addPoint(const QPointF &point);

    const Intersection *intersectionAt(int index) const;

    void addIntersection(int index, const Intersection &intersection);

    void mergePoints();

private:

    QDataBuffer<QPointF> m_points;

    QDataBuffer<Segment> m_segments;

    QDataBuffer<QBezier> m_beziers;

    QDataBuffer<Intersection> m_intersections;

    int m_pathId;

};

class Q_AUTOTEST_EXPORT QWingedEdge

{

public:

    struct TraversalStatus

    {

        int edge;

        QPathEdge::Traversal traversal;

        QPathEdge::Direction direction;

        void flipDirection();

        void flipTraversal();

        void flip();

    };

    QWingedEdge();

    QWingedEdge(const QPainterPath &subject, const QPainterPath &clip);

    void simplify();

    QPainterPath toPath() const;

    int edgeCount() const;

    QPathEdge *edge(int edge);

    const QPathEdge *edge(int edge) const;

    int vertexCount() const;

    int addVertex(const QPointF &p);

    QPathVertex *vertex(int vertex);

    const QPathVertex *vertex(int vertex) const;

    TraversalStatus next(const TraversalStatus &status) const;

    int addEdge(const QPointF &a, const QPointF &b, const QBezier *bezier = 0, qreal t0 = 0, qreal t1 = 1);

    int addEdge(int vertexA, int vertexB, const QBezier *bezier = 0, qreal t0 = 0, qreal t1 = 1);

    bool isInside(qreal x, qreal y) const;

    static QPathEdge::Traversal flip(QPathEdge::Traversal traversal);

    static QPathEdge::Direction flip(QPathEdge::Direction direction);

private:

    void intersectAndAdd();

    void printNode(int i, FILE *handle);

    QBezier bezierFromIndex(int index) const;

    void removeEdge(int ei);

    void addBezierEdge(const QBezier *bezier, const QPointF &a, const QPointF &b, qreal alphaA, qreal alphaB, int path);

    void addBezierEdge(const QBezier *bezier, int vertexA, int vertexB, qreal alphaA, qreal alphaB, int path);

    int insert(const QPathVertex &vertex);

    TraversalStatus findInsertStatus(int vertex, int edge) const;

    qreal delta(int vertex, int a, int b) const;

    QDataBuffer<QPathEdge> m_edges;

    QDataBuffer<QPathVertex> m_vertices;

    QVector<qreal> m_splitPoints;

    QPathSegments m_segments;

};

inline QPathEdge::QPathEdge(int a, int b)

    : flag(0)

    , windingA(0)

    , windingB(0)

    , first(a)

    , second(b)

    , angle(0)

    , invAngle(0)

    , bezier(0)

    , t0(0)

    , t1(0)

{

    m_next[0][0] = -1;

    m_next[1][0] = -1;

    m_next[0][0] = -1;

    m_next[1][0] = -1;

}

inline int QPathEdge::next(Traversal traversal, Direction direction) const

{

    return m_next[int(traversal)][int(direction)];

}

inline void QPathEdge::setNext(Traversal traversal, Direction direction, int next)

{

    m_next[int(traversal)][int(direction)] = next;

}

inline void QPathEdge::setNext(Direction direction, int next)

{

    m_next[0][int(direction)] = next;

    m_next[1][int(direction)] = next;

}

inline QPathEdge::Direction QPathEdge::directionTo(int vertex) const

{

    return first == vertex ? Backward : Forward;

}

inline int QPathEdge::vertex(Direction direction) const

{

    return direction == Backward ? first : second;

}

inline QPathVertex::QPathVertex(const QPointF &p, int e)

    : edge(e)

    , x(p.x())

    , y(p.y())

{

}

inline QPathVertex::operator QPointF() const

{

    return QPointF(x, y);

}

inline QPathSegments::QPathSegments()

{

}

inline int QPathSegments::segments() const

{

    return m_segments.size();

}

inline int QPathSegments::points() const

{

    return m_points.size();

}

inline const QPointF &QPathSegments::pointAt(int i) const

{

    return m_points.at(i);

}

inline int QPathSegments::addPoint(const QPointF &point)

{

    m_points << point;

    return m_points.size() - 1;

}

inline const QPathSegments::Segment &QPathSegments::segmentAt(int index) const

{

    return m_segments.at(index);

}

inline const QLineF QPathSegments::lineAt(int index) const

{

    const Segment &segment = m_segments.at(index);

    return QLineF(m_points.at(segment.va), m_points.at(segment.vb));

}

inline const QBezier *QPathSegments::bezierAt(int index) const

{

    const Segment &segment = m_segments.at(index);

    if (segment.bezier >= 0)

        return &m_beziers.at(segment.bezier);

    else

        return 0;

}

inline const QRectF &QPathSegments::elementBounds(int index) const

{

    return m_segments.at(index).bounds;

}

inline int QPathSegments::pathId(int index) const

{

    return m_segments.at(index).path;

}

inline const QPathSegments::Intersection *QPathSegments::intersectionAt(int index) const

{

    const int intersection = m_segments.at(index).intersection;

    if (intersection < 0)

        return 0;

    else

        return &m_intersections.at(intersection);

}

inline int QPathSegments::intersections() const

{

    return m_intersections.size();

}

inline void QPathSegments::addIntersection(int index, const Intersection &intersection)

{

    m_intersections << intersection;

    Segment &segment = m_segments.at(index);

    if (segment.intersection < 0) {

        segment.intersection = m_intersections.size() - 1;

    } else {

        Intersection *isect = &m_intersections.at(segment.intersection);

        while (isect->next != 0)

            isect += isect->next;

        isect->next = (m_intersections.size() - 1) - (isect - m_intersections.data());

    }

}

inline void QWingedEdge::TraversalStatus::flipDirection()

{

    direction = QWingedEdge::flip(direction);

}

inline void QWingedEdge::TraversalStatus::flipTraversal()

{

    traversal = QWingedEdge::flip(traversal);

}

inline void QWingedEdge::TraversalStatus::flip()

{

    flipDirection();

    flipTraversal();

}

inline int QWingedEdge::edgeCount() const

{

    return m_edges.size();

}

inline QPathEdge *QWingedEdge::edge(int edge)

{

    return edge < 0 ? 0 : &m_edges.at(edge);

}

inline const QPathEdge *QWingedEdge::edge(int edge) const

{

    return edge < 0 ? 0 : &m_edges.at(edge);

}

inline int QWingedEdge::vertexCount() const

{

    return m_vertices.size();

}

inline int QWingedEdge::addVertex(const QPointF &p)

{

    m_vertices << p;

    return m_vertices.size() - 1;

}

inline QPathVertex *QWingedEdge::vertex(int vertex)

{

    return vertex < 0 ? 0 : &m_vertices.at(vertex);

}

inline const QPathVertex *QWingedEdge::vertex(int vertex) const

{

    return vertex < 0 ? 0 : &m_vertices.at(vertex);

}

inline QPathEdge::Traversal QWingedEdge::flip(QPathEdge::Traversal traversal)

{

    return traversal == QPathEdge::RightTraversal ? QPathEdge::LeftTraversal : QPathEdge::RightTraversal;

}

inline QPathEdge::Direction QWingedEdge::flip(QPathEdge::Direction direction)

{

    return direction == QPathEdge::Forward ? QPathEdge::Backward : QPathEdge::Forward;

}

QT_END_NAMESPACE

QT_END_HEADER

#endif // QPATHCLIPPER_P_H