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39
40#ifndef QBSPTREE_P_H
41#define QBSPTREE_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 <qvector.h>
56#include <qrect.h>
57
58QT_BEGIN_NAMESPACE
59
60class QBspTree
61{
62public:
63
64 struct Node
65 {
66 enum Type { None = 0, VerticalPlane = 1, HorizontalPlane = 2, Both = 3 };
67 inline Node() : pos(0), type(None) {}
68 int pos;
69 Type type;
70 };
71 typedef Node::Type NodeType;
72
73 struct Data
74 {
75 Data(void *p) : ptr(p) {}
76 Data(int n) : i(n) {}
77 union {
78 void *ptr;
79 int i;
80 };
81 };
82 typedef QBspTree::Data QBspTreeData;
83 typedef void callback(QVector<int> &leaf, const QRect &area, uint visited, QBspTreeData data);
84
85 QBspTree();
86
87 void create(int n, int d = -1);
88 void destroy();
89
90 inline void init(const QRect &area, NodeType type) { init(area, depth, type, index: 0); }
91
92 void climbTree(const QRect &rect, callback *function, QBspTreeData data);
93
94 inline int leafCount() const { return leaves.count(); }
95 inline QVector<int> &leaf(int i) { return leaves[i]; }
96 inline void insertLeaf(const QRect &r, int i) { climbTree(rect: r, function: &insert, data: i, index: 0); }
97 inline void removeLeaf(const QRect &r, int i) { climbTree(rect: r, function: &remove, data: i, index: 0); }
98
99protected:
100 void init(const QRect &area, int depth, NodeType type, int index);
101 void climbTree(const QRect &rect, callback *function, QBspTreeData data, int index);
102
103 inline int parentIndex(int i) const { return (i & 1) ? ((i - 1) / 2) : ((i - 2) / 2); }
104 inline int firstChildIndex(int i) const { return ((i * 2) + 1); }
105
106 static void insert(QVector<int> &leaf, const QRect &area, uint visited, QBspTreeData data);
107 static void remove(QVector<int> &leaf, const QRect &area, uint visited, QBspTreeData data);
108
109private:
110 uint depth;
111 mutable uint visited;
112 QVector<Node> nodes;
113 mutable QVector< QVector<int> > leaves; // the leaves are just indices into the items
114};
115
116QT_END_NAMESPACE
117
118#endif // QBSPTREE_P_H
119

source code of qtbase/src/widgets/itemviews/qbsptree_p.h