Add method for manually inserting features into spatial indexes

i.e. inserting a feature with a different bounding box to that
feature's actual geometry

Author: nyalldawson

python/core/qgsspatialindex.sip

@@ -54,6 +54,14 @@ Add feature to index
  :rtype: bool
 %End
 
+    bool insertFeature( QgsFeatureId id, const QgsRectangle &bounds );
+%Docstring
+ Add a feature ``id`` to the index with a specified bounding box.
+ :return: true if feature was successfully added to index.
+.. versionadded:: 3.0
+ :rtype: bool
+%End
+
     bool deleteFeature( const QgsFeature &f );
 %Docstring
 Remove feature from index
@@ -84,6 +92,19 @@ get reference count - just for debugging!
   protected:
 
 
+    static bool featureInfo( const QgsFeature &f, QgsRectangle &rect, QgsFeatureId &id );
+%Docstring
+ Calculates feature info to insert into index.
+ \param f input feature
+ \param rect will be set to feature's geometry bounding box
+ \param id will be set to feature's ID
+ :return: true if feature info was successfully retrieved and the feature can be added to
+ the index
+.. versionadded:: 3.0
+ :rtype: bool
+%End
+
+
 };
 
 

src/core/qgsspatialindex.cpp

@@ -253,24 +253,38 @@ SpatialIndex::Region QgsSpatialIndex::rectToRegion( const QgsRectangle &rect )
 
 bool QgsSpatialIndex::featureInfo( const QgsFeature &f, SpatialIndex::Region &r, QgsFeatureId &id )
 {
-  if ( !f.hasGeometry() )
+  QgsRectangle rect;
+  if ( !featureInfo( f, rect, id ) )
     return false;
 
-  QgsGeometry g = f.geometry();
+  r = rectToRegion( rect );
+  return true;
+}
+
+bool QgsSpatialIndex::featureInfo( const QgsFeature &f, QgsRectangle &rect, QgsFeatureId &id )
+{
+  if ( !f.hasGeometry() )
+    return false;
 
   id = f.id();
-  r = rectToRegion( g.boundingBox() );
+  rect = f.geometry().boundingBox();
   return true;
 }
 
-
 bool QgsSpatialIndex::insertFeature( const QgsFeature &f )
 {
-  SpatialIndex::Region r;
+  QgsRectangle rect;
   QgsFeatureId id;
-  if ( !featureInfo( f, r, id ) )
+  if ( !featureInfo( f, rect, id ) )
     return false;
 
+  return insertFeature( id, rect );
+}
+
+bool QgsSpatialIndex::insertFeature( QgsFeatureId id, const QgsRectangle &rect )
+{
+  SpatialIndex::Region r( rectToRegion( rect ) );
+
   // TODO: handle possible exceptions correctly
   try
   {

src/core/qgsspatialindex.h

@@ -81,6 +81,13 @@ class CORE_EXPORT QgsSpatialIndex
     //! Add feature to index
     bool insertFeature( const QgsFeature &f );
 
+    /**
+     * Add a feature \a id to the index with a specified bounding box.
+     * \returns true if feature was successfully added to index.
+     * \since QGIS 3.0
+    */
+    bool insertFeature( QgsFeatureId id, const QgsRectangle &bounds );
+
     //! Remove feature from index
     bool deleteFeature( const QgsFeature &f );
 
@@ -101,9 +108,27 @@ class CORE_EXPORT QgsSpatialIndex
   protected:
     //! \note not available in Python bindings
     static SpatialIndex::Region rectToRegion( const QgsRectangle &rect ) SIP_SKIP;
-    //! \note not available in Python bindings
+
+    /** Calculates feature info to insert into index.
+    * \param f input feature
+    * \param r will be set to spatial index region
+    * \param id will be set to feature's ID
+    * \returns true if feature info was successfully retrieved and the feature can be added to
+    * the index
+    * \note not available in Python bindings
+    */
     static bool featureInfo( const QgsFeature &f, SpatialIndex::Region &r, QgsFeatureId &id ) SIP_SKIP;
 
+    /** Calculates feature info to insert into index.
+     * \param f input feature
+     * \param rect will be set to feature's geometry bounding box
+     * \param id will be set to feature's ID
+     * \returns true if feature info was successfully retrieved and the feature can be added to
+     * the index
+     * \since QGIS 3.0
+     */
+    static bool featureInfo( const QgsFeature &f, QgsRectangle &rect, QgsFeatureId &id );
+
     friend class QgsFeatureIteratorDataStream; // for access to featureInfo()
 
   private:

tests/src/core/testqgsspatialindex.cpp

@@ -82,6 +82,23 @@ class TestQgsSpatialIndex : public QObject
       QVERIFY( fids2.contains( 3 ) );
     }
 
+    void testQueryManualInsert()
+    {
+      QgsSpatialIndex index;
+      index.insertFeature( 1, QgsRectangle( 2, 3, 2, 3 ) );
+      index.insertFeature( 2, QgsRectangle( 12, 13, 12, 13 ) );
+      index.insertFeature( 3, QgsRectangle( 14, 13, 14, 13 ) );
+
+      QList<QgsFeatureId> fids = index.intersects( QgsRectangle( 1, 2, 3, 4 ) );
+      QVERIFY( fids.count() == 1 );
+      QVERIFY( fids.at( 0 ) == 1 );
+
+      QList<QgsFeatureId> fids2 = index.intersects( QgsRectangle( 10, 12, 15, 14 ) );
+      QVERIFY( fids2.count() == 2 );
+      QVERIFY( fids2.contains( 2 ) );
+      QVERIFY( fids2.contains( 3 ) );
+    }
+
     void testCopy()
     {
       QgsSpatialIndex *index = new QgsSpatialIndex;