Modify kdbush to store feature id alonside point, for optimised stora…

…ge/retrieval

external/kdbush/include/kdbush.hpp

@@ -16,7 +16,7 @@ struct nth {
     }
 };
 
-template <typename TPoint, typename TIndex = std::size_t>
+template <typename TPoint, typename TContainer, typename TIndex = std::size_t>
 class KDBush {
 
 public:
@@ -54,12 +54,12 @@ class KDBush {
         if (size == 0) return;
 
         points.reserve(size);
-        ids.reserve(size);
+        //ids.reserve(size);
 
         TIndex i = 0;
         for (auto p = points_begin; p != points_end; p++) {
             points.emplace_back(nth<0, TPoint>::get(*p), nth<1, TPoint>::get(*p));
-            ids.push_back(i++);
+            //ids.push_back(i++);
         }
 
         sortKD(0, size - 1, 0);
@@ -71,17 +71,17 @@ class KDBush {
                const TNumber maxX,
                const TNumber maxY,
                const TVisitor &visitor) {
-        range(minX, minY, maxX, maxY, visitor, 0, static_cast<TIndex>(ids.size() - 1), 0);
+        range(minX, minY, maxX, maxY, visitor, 0, static_cast<TIndex>(points.size() - 1), 0);
     }
 
     template <typename TVisitor>
     void within(const TNumber qx, const TNumber qy, const TNumber r, const TVisitor &visitor) {
-        within(qx, qy, r, visitor, 0, static_cast<TIndex>(ids.size() - 1), 0);
+        within(qx, qy, r, visitor, 0, static_cast<TIndex>(points.size() - 1), 0);
     }
 
 protected:
-    std::vector<TIndex> ids;
-    std::vector<std::pair<TNumber, TNumber>> points;
+    //std::vector<TIndex> ids;
+    std::vector<TContainer> points;
     std::uint8_t nodeSize;
 
     template <typename TVisitor>
@@ -93,21 +93,23 @@ class KDBush {
                const TIndex left,
                const TIndex right,
                const std::uint8_t axis) {
+        if ( points.empty() )
+            return;
 
         if (right - left <= nodeSize) {
             for (auto i = left; i <= right; i++) {
-                const TNumber x = std::get<0>(points[i]);
-                const TNumber y = std::get<1>(points[i]);
-                if (x >= minX && x <= maxX && y >= minY && y <= maxY) visitor(ids[i]);
+                const TNumber x = std::get<0>(points[i].coords);
+                const TNumber y = std::get<1>(points[i].coords);
+                if (x >= minX && x <= maxX && y >= minY && y <= maxY) visitor(points[i]);
             }
             return;
         }
 
         const TIndex m = (left + right) >> 1;
-        const TNumber x = std::get<0>(points[m]);
-        const TNumber y = std::get<1>(points[m]);
+        const TNumber x = std::get<0>(points[m].coords);
+        const TNumber y = std::get<1>(points[m].coords);
 
-        if (x >= minX && x <= maxX && y >= minY && y <= maxY) visitor(ids[m]);
+        if (x >= minX && x <= maxX && y >= minY && y <= maxY) visitor(points[m]);
 
         if (axis == 0 ? minX <= x : minY <= y)
             range(minX, minY, maxX, maxY, visitor, left, m - 1, (axis + 1) % 2);
@@ -125,22 +127,25 @@ class KDBush {
                 const TIndex right,
                 const std::uint8_t axis) {
 
+        if ( points.empty() )
+            return;
+
         const TNumber r2 = r * r;
 
         if (right - left <= nodeSize) {
             for (auto i = left; i <= right; i++) {
-                const TNumber x = std::get<0>(points[i]);
-                const TNumber y = std::get<1>(points[i]);
-                if (sqDist(x, y, qx, qy) <= r2) visitor(ids[i]);
+                const TNumber x = std::get<0>(points[i].coords);
+                const TNumber y = std::get<1>(points[i].coords);
+                if (sqDist(x, y, qx, qy) <= r2) visitor(points[i]);
             }
             return;
         }
 
         const TIndex m = (left + right) >> 1;
-        const TNumber x = std::get<0>(points[m]);
-        const TNumber y = std::get<1>(points[m]);
+        const TNumber x = std::get<0>(points[m].coords);
+        const TNumber y = std::get<1>(points[m].coords);
 
-        if (sqDist(x, y, qx, qy) <= r2) visitor(ids[m]);
+        if (sqDist(x, y, qx, qy) <= r2) visitor(points[m]);
 
         if (axis == 0 ? qx - r <= x : qy - r <= y)
             within(qx, qy, r, visitor, left, m - 1, (axis + 1) % 2);
@@ -175,20 +180,20 @@ class KDBush {
                 select<I>(k, std::max(left, TIndex(r)), std::min(right, TIndex(r + s)));
             }
 
-            const TNumber t = std::get<I>(points[k]);
+            const TNumber t = std::get<I>(points[k].coords);
             TIndex i = left;
             TIndex j = right;
 
             swapItem(left, k);
-            if (std::get<I>(points[right]) > t) swapItem(left, right);
+            if (std::get<I>(points[right].coords) > t) swapItem(left, right);
 
             while (i < j) {
                 swapItem(i++, j--);
-                while (std::get<I>(points[i]) < t) i++;
-                while (std::get<I>(points[j]) > t) j--;
+                while (std::get<I>(points[i].coords) < t) i++;
+                while (std::get<I>(points[j].coords) > t) j--;
             }
 
-            if (std::get<I>(points[left]) == t)
+            if (std::get<I>(points[left].coords) == t)
                 swapItem(left, j);
             else {
                 swapItem(++j, right);
@@ -200,7 +205,7 @@ class KDBush {
     }
 
     void swapItem(const TIndex i, const TIndex j) {
-        std::iter_swap(ids.begin() + static_cast<std::int32_t>(i), ids.begin() + static_cast<std::int32_t>(j));
+        // std::iter_swap(ids.begin() + static_cast<std::int32_t>(i), ids.begin() + static_cast<std::int32_t>(j));
         std::iter_swap(points.begin() + static_cast<std::int32_t>(i), points.begin() + static_cast<std::int32_t>(j));
     }
 

python/core/auto_generated/qgsspatialindexkdbushdata.sip.in

@@ -0,0 +1,47 @@
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/core/qgsspatialindexkdbushdata.h                                 *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/
+
+
+
+
+class QgsSpatialIndexKDBushData
+{
+%Docstring
+
+A container for data stored inside a QgsSpatialIndexKDBush index.
+
+.. versionadded:: 3.4
+%End
+
+%TypeHeaderCode
+#include "qgsspatialindexkdbushdata.h"
+%End
+  public:
+
+    QgsSpatialIndexKDBushData( QgsFeatureId id, double x, double y );
+%Docstring
+Constructor for QgsSpatialIndexKDBushData, for a feature with the
+given ``id`` and ``x``, ``y`` coordinate.
+%End
+
+
+    QgsPointXY point() const;
+%Docstring
+Returns the indexed point.
+%End
+
+    QgsFeatureId id;
+};
+
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/core/qgsspatialindexkdbushdata.h                                 *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/

python/core/core_auto.sip

@@ -113,6 +113,7 @@
 %Include auto_generated/qgssnappingutils.sip
 %Include auto_generated/qgsspatialindex.sip
 %Include auto_generated/qgsspatialindexkdbush.sip
+%Include auto_generated/qgsspatialindexkdbushdata.sip
 %Include auto_generated/qgssqlstatement.sip
 %Include auto_generated/qgsstatisticalsummary.sip
 %Include auto_generated/qgsstringstatisticalsummary.sip

src/core/CMakeLists.txt

@@ -915,6 +915,7 @@ SET(QGIS_CORE_HDRS
   qgsspatialindex.h
   qgsspatialindexkdbush.h
   qgsspatialindexkdbush_p.h
+  qgsspatialindexkdbushdata.h
   qgsspatialiteutils.h
   qgssqlstatement.h
   qgssqliteutils.h

src/core/qgsspatialindexkdbush.cpp

@@ -16,10 +16,10 @@
  ***************************************************************************/
 
 #include "qgsspatialindexkdbush.h"
-#include "qgsspatialindexkdbush_p.h"
 #include "qgsfeatureiterator.h"
 #include "qgsfeedback.h"
 #include "qgsfeaturesource.h"
+#include "qgsspatialindexkdbush_p.h"
 
 QgsSpatialIndexKDBush::QgsSpatialIndexKDBush( QgsFeatureIterator &fi, QgsFeedback *feedback )
   : d( new QgsSpatialIndexKDBushPrivate( fi, feedback ) )
@@ -59,11 +59,11 @@ QgsSpatialIndexKDBush::~QgsSpatialIndexKDBush()
 QSet<QgsFeatureId> QgsSpatialIndexKDBush::within( const QgsPointXY &point, double radius ) const
 {
   QSet<QgsFeatureId> result;
-  d->index->within( point.x(), point.y(), radius, [&result]( const QgsFeatureId id ) { result.insert( id ); } );
+  d->index->within( point.x(), point.y(), radius, [&result]( const QgsSpatialIndexKDBushData & p ) { result.insert( p.id ); } );
   return result;
 }
 
-void QgsSpatialIndexKDBush::within( const QgsPointXY &point, double radius, const std::function<void( QgsFeatureId )> &visitor )
+void QgsSpatialIndexKDBush::within( const QgsPointXY &point, double radius, const std::function<void( QgsSpatialIndexKDBushData )> &visitor )
 {
   d->index->within( point.x(), point.y(), radius, visitor );
 }
@@ -84,11 +84,11 @@ QSet<QgsFeatureId> QgsSpatialIndexKDBush::intersect( const QgsRectangle &rectang
   d->index->range( rectangle.xMinimum(),
                    rectangle.yMinimum(),
                    rectangle.xMaximum(),
-  rectangle.yMaximum(), [&result]( const QgsFeatureId id ) { result << id; } );
+  rectangle.yMaximum(), [&result]( const QgsSpatialIndexKDBushData & p ) { result << p.id; } );
   return result;
 }
 
-void QgsSpatialIndexKDBush::intersect( const QgsRectangle &rectangle, const std::function<void ( QgsFeatureId )> &visitor ) const
+void QgsSpatialIndexKDBush::intersect( const QgsRectangle &rectangle, const std::function<void( QgsSpatialIndexKDBushData )> &visitor ) const
 {
   d->index->range( rectangle.xMinimum(),
                    rectangle.yMinimum(),

src/core/qgsspatialindexkdbush.h

@@ -27,6 +27,7 @@ class QgsRectangle;
 
 #include "qgis_core.h"
 #include "qgsfeature.h"
+#include "qgsspatialindexkdbushdata.h"
 #include <memory>
 #include <QList>
 
@@ -92,7 +93,7 @@ class CORE_EXPORT QgsSpatialIndexKDBush
      *
      * \note Not available in Python bindings
      */
-    void intersect( const QgsRectangle &rectangle, const std::function<void( QgsFeatureId )> &visitor ) const SIP_SKIP;
+    void intersect( const QgsRectangle &rectangle, const std::function<void( QgsSpatialIndexKDBushData )> &visitor ) const SIP_SKIP;
 
     /**
      * Returns the set of features which are within the given search \a radius
@@ -106,7 +107,7 @@ class CORE_EXPORT QgsSpatialIndexKDBush
      *
      * \note Not available in Python bindings
      */
-    void within( const QgsPointXY &point, double radius, const std::function<void( QgsFeatureId )> &visitor ) SIP_SKIP;
+    void within( const QgsPointXY &point, double radius, const std::function<void( QgsSpatialIndexKDBushData )> &visitor ) SIP_SKIP;
 
     /**
      * Fetches the point from the index with matching \a id and stores it in \a point.

src/core/qgsspatialindexkdbush_p.h

@@ -32,15 +32,16 @@
 //
 
 #include "qgsfeature.h"
-
+#include "qgsspatialindexkdbushdata.h"
 #include "qgsfeatureiterator.h"
 #include "qgsfeedback.h"
 #include "qgsfeaturesource.h"
 #include <memory>
 #include <QList>
 #include "kdbush.hpp"
 
-class PointXYKDBush : public kdbush::KDBush< std::pair<double, double>, QgsFeatureId >
+
+class PointXYKDBush : public kdbush::KDBush< std::pair<double, double>, QgsSpatialIndexKDBushData, std::size_t >
 {
   public:
 
@@ -52,14 +53,13 @@ class PointXYKDBush : public kdbush::KDBush< std::pair<double, double>, QgsFeatu
     explicit PointXYKDBush( const QgsFeatureSource &source, QgsFeedback *feedback )
     {
       points.reserve( source.featureCount() );
-      ids.reserve( source.featureCount() );
       QgsFeatureIterator it = source.getFeatures( QgsFeatureRequest().setSubsetOfAttributes( QgsAttributeList() ) );
       fillFromIterator( it, feedback );
     }
 
     void fillFromIterator( QgsFeatureIterator &fi, QgsFeedback *feedback = nullptr )
     {
-      QgsFeatureId size = 0;
+      std::size_t size = 0;
 
       QgsFeature f;
       while ( fi.nextFeature( f ) )
@@ -73,29 +73,31 @@ class PointXYKDBush : public kdbush::KDBush< std::pair<double, double>, QgsFeatu
         if ( QgsWkbTypes::flatType( f.geometry().wkbType() ) == QgsWkbTypes::Point )
         {
           const QgsPoint *point = qgsgeometry_cast< const QgsPoint * >( f.geometry().constGet() );
-          points.emplace_back( point->x(), point->y() );
-          mIdToPoint[ f.id() ] = QgsPointXY( point->x(), point->y() );
+          points.emplace_back( QgsSpatialIndexKDBushData( f.id(), point->x(), point->y() ) );
         }
         else
         {
           // not a point
           continue;
         }
 
-        ids.push_back( f.id() );
         size++;
       }
 
+      if ( size == 0 )
+        return;
+
       sortKD( 0, size - 1, 0 );
     }
 
     bool point( QgsFeatureId id, QgsPointXY &point ) const
     {
-      auto it = mIdToPoint.constFind( id );
-      if ( it == mIdToPoint.constEnd() )
+      auto it = std::find_if( points.begin(), points.end(),
+      [id]( const QgsSpatialIndexKDBushData & d ) { return d.id == id; } );
+      if ( it == points.end() )
         return false;
 
-      point = *it;
+      point = QgsPointXY( it->coords.first, it->coords.second );
       return true;
     }
 
@@ -104,10 +106,6 @@ class PointXYKDBush : public kdbush::KDBush< std::pair<double, double>, QgsFeatu
       return points.size();
     }
 
-  private:
-
-    QHash< QgsFeatureId, QgsPointXY > mIdToPoint;
-
 };
 
 class QgsSpatialIndexKDBushPrivate