QGIS API Documentation  3.21.0-Master (5b68dc587e)
palrtree.h
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1 /***************************************************************************
2  parlrtree.h
3  ------------------------
4  Date : December 2019
5  Copyright : (C) 2019 by Nyall Dawson
6  Email : nyall dot dawson at gmail dot com
7  ***************************************************************************
8  * *
9  * This program is free software; you can redistribute it and/or modify *
10  * it under the terms of the GNU General Public License as published by *
11  * the Free Software Foundation; either version 2 of the License, or *
12  * (at your option) any later version. *
13  * *
14  ***************************************************************************/
15 
16 #include "RTree.h"
17 #include "qgsrectangle.h"
18 #include <array>
19 
20 #ifndef QGSPALRTREE_H
21 #define QGSPALRTREE_H
22 
23 #define SIP_NO_FILE
24 
34 template <typename T>
35 class PalRtree : public RTree<T *, float, 2, float>
36 {
37  public:
38 
43  PalRtree( const QgsRectangle &maxBounds )
44  : mXMin( maxBounds.xMinimum() )
45  , mYMin( maxBounds.yMinimum() )
46  , mXRes( ( std::numeric_limits< float >::max() - 1 ) / ( maxBounds.xMaximum() - maxBounds.xMinimum() ) )
47  , mYRes( ( std::numeric_limits< float >::max() - 1 ) / ( maxBounds.yMaximum() - maxBounds.yMinimum() ) )
48  , mMaxBounds( maxBounds )
49  {
50 
51  }
52 
59  void insert( T *data, const QgsRectangle &bounds )
60  {
61  std::array< float, 4 > scaledBounds = scaleBounds( bounds );
62  this->Insert(
63  {
64  scaledBounds[0], scaledBounds[ 1]
65  },
66  {
67  scaledBounds[2], scaledBounds[3]
68  },
69  data );
70  }
71 
78  void remove( T *data, const QgsRectangle &bounds )
79  {
80  std::array< float, 4 > scaledBounds = scaleBounds( bounds );
81  this->Remove(
82  {
83  scaledBounds[0], scaledBounds[ 1]
84  },
85  {
86  scaledBounds[2], scaledBounds[3]
87  },
88  data );
89  }
90 
96  bool intersects( const QgsRectangle &bounds, const std::function< bool( T *data )> &callback ) const
97  {
98  std::array< float, 4 > scaledBounds = scaleBounds( bounds );
99  this->Search(
100  {
101  scaledBounds[0], scaledBounds[ 1]
102  },
103  {
104  scaledBounds[2], scaledBounds[3]
105  },
106  callback );
107  return true;
108  }
109 
110  private:
111 
112  // Coordinates are scaled inside the index so that they cover the maximum range for float values
113  double mXMin = 0;
114  double mYMin = 0;
115  double mXRes = 1;
116  double mYRes = 1;
117  const QgsRectangle mMaxBounds;
118  std::array<float, 4> scaleBounds( const QgsRectangle &bounds ) const
119  {
120  return
121  {
122  static_cast< float >( ( std::max( bounds.xMinimum(), mMaxBounds.xMinimum() ) - mXMin ) / mXRes ),
123  static_cast< float >( ( std::max( bounds.yMinimum(), mMaxBounds.yMinimum() ) - mYMin ) / mYRes ),
124  static_cast< float >( ( std::min( bounds.xMaximum(), mMaxBounds.xMaximum() ) - mXMin ) / mXRes ),
125  static_cast< float >( ( std::min( bounds.yMaximum(), mMaxBounds.yMaximum() ) - mYMin ) / mYRes )
126  };
127  }
128 };
129 
130 #endif
131 
A rtree spatial index for use in the pal labeling engine.
Definition: palrtree.h:36
void insert(T *data, const QgsRectangle &bounds)
Inserts new data into the spatial index, with the specified bounds.
Definition: palrtree.h:59
void remove(T *data, const QgsRectangle &bounds)
Removes existing data from the spatial index, with the specified bounds.
Definition: palrtree.h:78
PalRtree(const QgsRectangle &maxBounds)
Constructor for PalRtree.
Definition: palrtree.h:43
bool intersects(const QgsRectangle &bounds, const std::function< bool(T *data)> &callback) const
Performs an intersection check against the index, for data intersecting the specified bounds.
Definition: palrtree.h:96
A rectangle specified with double values.
Definition: qgsrectangle.h:42
double yMaximum() const SIP_HOLDGIL
Returns the y maximum value (top side of rectangle).
Definition: qgsrectangle.h:193
double xMaximum() const SIP_HOLDGIL
Returns the x maximum value (right side of rectangle).
Definition: qgsrectangle.h:183
double xMinimum() const SIP_HOLDGIL
Returns the x minimum value (left side of rectangle).
Definition: qgsrectangle.h:188
double yMinimum() const SIP_HOLDGIL
Returns the y minimum value (bottom side of rectangle).
Definition: qgsrectangle.h:198