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39
40#ifndef QGRAPHICSSCENEBSPTREE_P_H
41#define QGRAPHICSSCENEBSPTREE_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists for the convenience
48// of other Qt classes. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtWidgets/private/qtwidgetsglobal_p.h>
55#include <QtCore/qlist.h>
56
57#include <QtCore/qrect.h>
58#include <QtCore/qset.h>
59#include <QtCore/qvector.h>
60
61QT_REQUIRE_CONFIG(graphicsview);
62
63QT_BEGIN_NAMESPACE
64
65class QGraphicsItem;
66class QGraphicsSceneBspTreeVisitor;
67class QGraphicsSceneInsertItemBspTreeVisitor;
68class QGraphicsSceneRemoveItemBspTreeVisitor;
69class QGraphicsSceneFindItemBspTreeVisitor;
70
71class QGraphicsSceneBspTree
72{
73public:
74 struct Node
75 {
76 enum Type { Horizontal, Vertical, Leaf };
77 union {
78 qreal offset;
79 int leafIndex;
80 };
81 Type type;
82 };
83
84 QGraphicsSceneBspTree();
85 ~QGraphicsSceneBspTree();
86
87 void initialize(const QRectF &rect, int depth);
88 void clear();
89
90 void insertItem(QGraphicsItem *item, const QRectF &rect);
91 void removeItem(QGraphicsItem *item, const QRectF &rect);
92 void removeItems(const QSet<QGraphicsItem *> &items);
93
94 QList<QGraphicsItem *> items(const QRectF &rect, bool onlyTopLevelItems = false) const;
95 int leafCount() const;
96
97 inline int firstChildIndex(int index) const
98 { return index * 2 + 1; }
99
100 inline int parentIndex(int index) const
101 { return index > 0 ? ((index & 1) ? ((index - 1) / 2) : ((index - 2) / 2)) : -1; }
102
103 QString debug(int index) const;
104
105private:
106 void initialize(const QRectF &rect, int depth, int index);
107 void climbTree(QGraphicsSceneBspTreeVisitor *visitor, const QRectF &rect, int index = 0) const;
108 QRectF rectForIndex(int index) const;
109
110 QVector<Node> nodes;
111 QVector<QList<QGraphicsItem *> > leaves;
112 int leafCnt;
113 QRectF rect;
114
115 QGraphicsSceneInsertItemBspTreeVisitor *insertVisitor;
116 QGraphicsSceneRemoveItemBspTreeVisitor *removeVisitor;
117 QGraphicsSceneFindItemBspTreeVisitor *findVisitor;
118};
119
120class QGraphicsSceneBspTreeVisitor
121{
122public:
123 virtual ~QGraphicsSceneBspTreeVisitor() { }
124 virtual void visit(QList<QGraphicsItem *> *items) = 0;
125};
126
127QT_END_NAMESPACE
128
129#endif // QGRAPHICSSCENEBSPTREE_P_H
130

source code of qtbase/src/widgets/graphicsview/qgraphicsscene_bsp_p.h