summaryrefslogtreecommitdiffstats
path: root/src/gui/painting/qpathclipper_p.h
blob: b2ab3b4eba69d31768e378005dadb232b06f24f8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** 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 either Technology Preview License Agreement or the
** Beta Release License Agreement.
**
** 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 1.0, included in the file LGPL_EXCEPTION.txt in this
** package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 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 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at http://www.qtsoftware.com/contact.
** $QT_END_LICENSE$
**
****************************************************************************/

#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;

    bool isBezier() 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 bool QPathEdge::isBezier() const
{
    return bezier >= 0;
}

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