MuseScore/libmscore/bsp.h
2013-05-13 19:43:59 +02:00

100 lines
2.8 KiB
C++

//=============================================================================
// MuseScore
// Music Composition & Notation
//
// Copyright (C) 2002-2011 Werner Schweer
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License version 2
// as published by the Free Software Foundation and appearing in
// the file LICENCE.GPL
//
// This code is from Qt implementation of QGraphicsItem
// Copyright (C) 1992-2007 Trolltech ASA. All rights reserved.
//=============================================================================
#ifndef __BSP_H__
#define __BSP_H__
namespace Ms {
class BspTreeVisitor;
class InsertItemBspTreeVisitor;
class RemoveItemBspTreeVisitor;
class FindItemBspTreeVisitor;
class Element;
//---------------------------------------------------------
// BspTree
// binary space partitioning
//---------------------------------------------------------
class BspTree
{
public:
struct Node {
enum Type { Horizontal, Vertical, Leaf };
union {
qreal offset;
int leafIndex;
};
Type type;
};
private:
uint depth;
void initialize(const QRectF& rect, int depth, int index);
void climbTree(BspTreeVisitor* visitor, const QPointF& pos, int index = 0);
void climbTree(BspTreeVisitor* visitor, const QRectF& rect, int index = 0);
void findItems(QList<Element*>* foundItems, const QRectF& rect, int index);
void findItems(QList<Element*>* foundItems, const QPointF& pos, int index);
QRectF rectForIndex(int index) const;
QVector<Node> nodes;
QVector<QList<Element*> > leaves;
int leafCnt;
QRectF rect;
InsertItemBspTreeVisitor* insertVisitor;
RemoveItemBspTreeVisitor* removeVisitor;
FindItemBspTreeVisitor* findVisitor;
public:
BspTree();
~BspTree();
void initialize(const QRectF& rect, int depth);
void clear();
void insert(Element* item);
void remove(Element* item);
QList<Element*> items(const QRectF& rect);
QList<Element*> items(const QPointF& pos);
int leafCount() const { return leafCnt; }
inline int firstChildIndex(int index) const { return index * 2 + 1; }
inline int parentIndex(int index) const {
return index > 0 ? ((index & 1) ? ((index - 1) / 2) : ((index - 2) / 2)) : -1;
}
#ifndef NDEBUG
QString debug(int index) const;
#endif
};
//---------------------------------------------------------
// BspTreeVisitor
//---------------------------------------------------------
class BspTreeVisitor
{
public:
virtual ~BspTreeVisitor() {}
virtual void visit(QList<Element*>* items) = 0;
};
} // namespace Ms
#endif