Make all QgsGeometry methods return values, not pointers

Reduces likelihood of crashes and leaks

Author: nyalldawson

doc/api_break.dox

@@ -226,10 +226,18 @@ true, as the method will return an empty geometry if the feature has no geometry
 <li>setFields( const QgsFields*, bool ) has been removed, use setFields( const QgsFields&, bool ) instead.</li>
 </ul>
 
+\subsection qgis_api_break_3_0_QgsGeometry QgsGeometry
+
+<ul>
+<li>All QgsGeometry methods now accept geometry references instead of pointers, and return a QgsGeometry
+value instead of a pointer.</li>
+</ul>
+
 \subsection qgis_api_break_3_0_QgsGeometryAnalyzer QgsGeometryAnalyzer
 
 <ul>
-<li>locateBetweenMeasures() and locateAlongMeasure() now take geometry references, not pointers</li>
+<li>locateBetweenMeasures() and locateAlongMeasure() now take geometry references, not pointers, and return 
+a QgsGeometry value rather than a pointer.</li>
 </ul>
 
 \subsection qgis_api_break_3_0_QgsGroupWMSDataDialog QgsGroupWMSDataDialog

python/analysis/vector/qgsgeometryanalyzer.sip

@@ -95,10 +95,10 @@ class QgsGeometryAnalyzer
                      bool forceSingleGeometry = false, QgsVectorDataProvider* memoryProvider = 0, QProgressDialog* p = 0 );
 
     /** Returns linear reference geometry as a multiline (or 0 if no match). Currently, the z-coordinates are considered to be the measures (no support for m-values in QGIS)*/
-    QgsGeometry* locateBetweenMeasures( double fromMeasure, double toMeasure, const QgsGeometry& lineGeom );
+    QgsGeometry locateBetweenMeasures( double fromMeasure, double toMeasure, const QgsGeometry& lineGeom );
     /** Returns linear reference geometry. Unlike the PostGIS function, this method always returns multipoint or 0 if no match (not geometry collection).
      * Currently, the z-coordinates are considered to be the measures (no support for m-values in QGIS)
      */
-    QgsGeometry* locateAlongMeasure( double measure, const QgsGeometry& lineGeom );
+    QgsGeometry locateAlongMeasure( double measure, const QgsGeometry& lineGeom );
 
 };

python/core/geometry/qgsgeometry.sip

@@ -65,21 +65,21 @@ class QgsGeometry
     bool isEmpty() const;
 
     /** Creates a new geometry from a WKT string */
-    static QgsGeometry* fromWkt( const QString& wkt ) /Factory/;
+    static QgsGeometry fromWkt( const QString& wkt );
     /** Creates a new geometry from a QgsPoint object*/
-    static QgsGeometry* fromPoint( const QgsPoint& point ) /Factory/;
+    static QgsGeometry fromPoint( const QgsPoint& point );
     /** Creates a new geometry from a QgsMultiPoint object */
-    static QgsGeometry* fromMultiPoint( const QgsMultiPoint& multipoint ) /Factory/;
+    static QgsGeometry fromMultiPoint( const QgsMultiPoint& multipoint );
     /** Creates a new geometry from a QgsPolyline object */
-    static QgsGeometry* fromPolyline( const QgsPolyline& polyline ) /Factory/;
+    static QgsGeometry fromPolyline( const QgsPolyline& polyline );
     /** Creates a new geometry from a QgsMultiPolyline object*/
-    static QgsGeometry* fromMultiPolyline( const QgsMultiPolyline& multiline ) /Factory/;
+    static QgsGeometry fromMultiPolyline( const QgsMultiPolyline& multiline );
     /** Creates a new geometry from a QgsPolygon */
-    static QgsGeometry* fromPolygon( const QgsPolygon& polygon ) /Factory/;
+    static QgsGeometry fromPolygon( const QgsPolygon& polygon );
     /** Creates a new geometry from a QgsMultiPolygon */
-    static QgsGeometry* fromMultiPolygon( const QgsMultiPolygon& multipoly ) /Factory/;
+    static QgsGeometry fromMultiPolygon( const QgsMultiPolygon& multipoly );
     /** Creates a new geometry from a QgsRectangle */
-    static QgsGeometry* fromRect( const QgsRectangle& rect ) /Factory/;
+    static QgsGeometry fromRect( const QgsRectangle& rect );
 
     /**
      * Set the geometry, feeding in a geometry in GEOS format.
@@ -408,42 +408,42 @@ class QgsGeometry
     bool intersects( const QgsRectangle& r ) const;
 
     /** Test for intersection with a geometry (uses GEOS) */
-    bool intersects( const QgsGeometry* geometry ) const;
+    bool intersects( const QgsGeometry& geometry ) const;
 
     /** Test for containment of a point (uses GEOS) */
     bool contains( const QgsPoint* p ) const;
 
     /** Test for if geometry is contained in another (uses GEOS)
      *  @note added in 1.5 */
-    bool contains( const QgsGeometry* geometry ) const;
+    bool contains( const QgsGeometry& geometry ) const;
 
     /** Test for if geometry is disjoint of another (uses GEOS)
      *  @note added in 1.5 */
-    bool disjoint( const QgsGeometry* geometry ) const;
+    bool disjoint( const QgsGeometry& geometry ) const;
 
     /** Test for if geometry equals another (uses GEOS)
      *  @note added in 1.5 */
-    bool equals( const QgsGeometry* geometry ) const;
+    bool equals( const QgsGeometry& geometry ) const;
 
     /** Test for if geometry touch another (uses GEOS)
      *  @note added in 1.5 */
-    bool touches( const QgsGeometry* geometry ) const;
+    bool touches( const QgsGeometry& geometry ) const;
 
     /** Test for if geometry overlaps another (uses GEOS)
      *  @note added in 1.5 */
-    bool overlaps( const QgsGeometry* geometry ) const;
+    bool overlaps( const QgsGeometry& geometry ) const;
 
     /** Test for if geometry is within another (uses GEOS)
      *  @note added in 1.5 */
-    bool within( const QgsGeometry* geometry ) const;
+    bool within( const QgsGeometry& geometry ) const;
 
     /** Test for if geometry crosses another (uses GEOS)
      *  @note added in 1.5 */
-    bool crosses( const QgsGeometry* geometry ) const;
+    bool crosses( const QgsGeometry& geometry ) const;
 
     /** Returns a buffer region around this geometry having the given width and with a specified number
         of segments used to approximate curves */
-    QgsGeometry* buffer( double distance, int segments ) const /Factory/;
+    QgsGeometry buffer( double distance, int segments ) const;
 
     /** Returns a buffer region around the geometry, with additional style options.
      * @param distance    buffer distance
@@ -454,44 +454,44 @@ class QgsGeometry
      * @note added in 2.4
      * @note needs GEOS >= 3.3 - otherwise always returns 0
      */
-    QgsGeometry* buffer( double distance, int segments, int endCapStyle, int joinStyle, double mitreLimit ) const /Factory/;
+    QgsGeometry buffer( double distance, int segments, int endCapStyle, int joinStyle, double mitreLimit ) const;
 
     /** Returns an offset line at a given distance and side from an input line.
      * See buffer() method for details on parameters.
      * @note added in 2.4
      * @note needs GEOS >= 3.3 - otherwise always returns 0
      */
-    QgsGeometry* offsetCurve( double distance, int segments, int joinStyle, double mitreLimit ) const /Factory/;
+    QgsGeometry offsetCurve( double distance, int segments, int joinStyle, double mitreLimit ) const;
 
     /** Returns a simplified version of this geometry using a specified tolerance value */
-    QgsGeometry* simplify( double tolerance )  const /Factory/;
+    QgsGeometry simplify( double tolerance )  const;
 
     /** Returns the center of mass of a geometry
      * @note for line based geometries, the center point of the line is returned,
      * and for point based geometries, the point itself is returned
      */
-    QgsGeometry* centroid() const /Factory/;
+    QgsGeometry centroid() const;
 
     /** Returns a point within a geometry */
-    QgsGeometry* pointOnSurface() const /Factory/;
+    QgsGeometry pointOnSurface() const;
 
     /** Returns the smallest convex polygon that contains all the points in the geometry. */
-    QgsGeometry* convexHull()  const /Factory/;
+    QgsGeometry convexHull() const;
 
     /**
      * Return interpolated point on line at distance
      * @note added in 1.9
      */
-    QgsGeometry* interpolate( double distance ) /Factory/;
+    QgsGeometry interpolate( double distance );
 
     /** Returns a geometry representing the points shared by this geometry and other. */
-    QgsGeometry* intersection( const QgsGeometry* geometry ) const /Factory/;
+    QgsGeometry intersection( const QgsGeometry& geometry ) const;
 
     /** Returns a geometry representing all the points in this geometry and other (a
      * union geometry operation).
      * @note this operation is not called union since its a reserved word in C++.
      */
-    QgsGeometry* combine( const QgsGeometry* geometry ) const /Factory/;
+    QgsGeometry combine( const QgsGeometry& geometry ) const;
 
     /** Merges any connected lines in a LineString/MultiLineString geometry and
      * converts them to single line strings.
@@ -503,10 +503,10 @@ class QgsGeometry
     QgsGeometry mergeLines() const;
 
     /** Returns a geometry representing the points making up this geometry that do not make up other. */
-    QgsGeometry* difference( const QgsGeometry* geometry ) const /Factory/;
+    QgsGeometry difference( const QgsGeometry& geometry ) const;
 
     /** Returns a geometry representing the points making up this geometry that do not make up other. */
-    QgsGeometry* symDifference( const QgsGeometry* geometry ) const /Factory/;
+    QgsGeometry symDifference( const QgsGeometry& geometry ) const;
 
     /** Returns an extruded version of this geometry. */
     QgsGeometry extrude( double x, double y );
@@ -531,7 +531,7 @@ class QgsGeometry
      * @return the converted geometry or nullptr if the conversion fails.
      * @note added in 2.2
      */
-    QgsGeometry* convertToType( Qgis::GeometryType destType, bool destMultipart = false ) const /Factory/;
+    QgsGeometry convertToType( Qgis::GeometryType destType, bool destMultipart = false ) const;
 
     /* Accessor functions for getting geometry data */
 
@@ -564,7 +564,7 @@ class QgsGeometry
 
     /** Return contents of the geometry as a list of geometries
      @note added in version 1.1 */
-    QList<QgsGeometry*> asGeometryCollection() const /Factory/;
+    QList<QgsGeometry> asGeometryCollection() const;
 
     /** Return contents of the geometry as a QPointF if wkbType is WKBPoint,
      * otherwise returns a null QPointF.
@@ -643,7 +643,7 @@ class QgsGeometry
      * @param geometryList a list of QgsGeometry* as input
      * @returns the new computed QgsGeometry, or null
      */
-    static QgsGeometry *unaryUnion( const QList<QgsGeometry*>& geometryList ) /Factory/;
+    static QgsGeometry unaryUnion( const QList<QgsGeometry>& geometryList );
 
     /** Converts the geometry to straight line segments, if it is a curved geometry type.
      * @note added in QGIS 2.10
@@ -704,15 +704,15 @@ class QgsGeometry
      * @param point source QPointF
      * @note added in QGIS 2.7
      */
-    static QgsGeometry* fromQPointF( QPointF point ) /Factory/;
+    static QgsGeometry fromQPointF( QPointF point );
 
     /** Construct geometry from a QPolygonF. If the polygon is closed than
      * the resultant geometry will be a polygon, if it is open than the
      * geometry will be a polyline.
      * @param polygon source QPolygonF
      * @note added in QGIS 2.7
      */
-    static QgsGeometry* fromQPolygonF( const QPolygonF& polygon ) /Factory/;
+    static QgsGeometry fromQPolygonF( const QPolygonF& polygon );
 
     /** Creates a QgsPolyline from a QPolygonF.
      * @param polygon source polygon
@@ -768,7 +768,7 @@ class QgsGeometry
      * of the geometry for each iteration. Smaller values result in "tighter" smoothing.
      * @note added in 2.9
      */
-    QgsGeometry* smooth( const unsigned int iterations, const double offset ) const;
+    QgsGeometry smooth( const unsigned int iterations, const double offset ) const;
 
     /** Smooths a polygon using the Chaikin algorithm*/
     QgsPolygon smoothPolygon( const QgsPolygon &polygon, const unsigned int iterations = 1, const double offset = 0.25 ) const;
@@ -794,5 +794,7 @@ class QgsGeometry
     //! Allows direct construction of QVariants from geometry.
     operator QVariant() const;
 
+    operator bool() const;
+
 }; // class QgsGeometry
 

python/core/qgsgeometrysimplifier.sip

@@ -12,7 +12,7 @@ class QgsAbstractGeometrySimplifier
     virtual ~QgsAbstractGeometrySimplifier();
 
     //! Returns a simplified version the specified geometry
-    virtual QgsGeometry* simplify( QgsGeometry* geometry ) const = 0;
+    virtual QgsGeometry simplify( const QgsGeometry& geometry ) const = 0;
     //! Simplifies the specified geometry
     virtual bool simplifyGeometry( QgsGeometry* geometry ) const = 0;
 
@@ -41,7 +41,7 @@ class QgsTopologyPreservingSimplifier : QgsAbstractGeometrySimplifier
     virtual ~QgsTopologyPreservingSimplifier();
 
     //! Returns a simplified version the specified geometry
-    virtual QgsGeometry* simplify( QgsGeometry* geometry ) const;
+    virtual QgsGeometry simplify( const QgsGeometry& geometry ) const;
     //! Simplifies the specified geometry
     virtual bool simplifyGeometry( QgsGeometry* geometry ) const;
 };

python/core/qgsmaptopixelgeometrysimplifier.sip

@@ -44,7 +44,7 @@ class QgsMapToPixelSimplifier : QgsAbstractGeometrySimplifier
     void setSimplifyAlgorithm( SimplifyAlgorithm simplifyAlgorithm );
 
     //! Returns a simplified version the specified geometry
-    virtual QgsGeometry* simplify( QgsGeometry* geometry ) const;
+    virtual QgsGeometry simplify( const QgsGeometry& geometry ) const;
     //! Simplifies the specified geometry
     virtual bool simplifyGeometry( QgsGeometry* geometry ) const;
 

python/core/qgsogcutils.sip

@@ -13,11 +13,11 @@ class QgsOgcUtils
        in default namespace (\verbatim {<Point>...</Point> \endverbatim) or in
        "gml" namespace (\verbatim <gml:Point>...</gml:Point> \endverbatim)
      */
-    static QgsGeometry* geometryFromGML( const QString& xmlString ) /Factory/;
+    static QgsGeometry geometryFromGML( const QString& xmlString );
 
     /** Static method that creates geometry from GML
       */
-    static QgsGeometry* geometryFromGML( const QDomNode& geometryNode ) /Factory/;
+    static QgsGeometry geometryFromGML( const QDomNode& geometryNode );
 
     /** Read rectangle from GML2 Box */
     static QgsRectangle rectangleFromGMLBox( const QDomNode& boxNode );

python/core/qgspallabeling.sip

@@ -742,7 +742,7 @@ class QgsPalLayerSettings
 
     QgsPoint ptZero;
     QgsPoint ptOne;
-    QgsGeometry* extentGeom;
+    QgsGeometry extentGeom;
     int mFeaturesToLabel; // total features that will probably be labeled, may be less (figured before PAL)
     int mFeatsSendingToPal; // total features tested for sending into PAL (relative to maxNumLabels)
     int mFeatsRegPal; // number of features registered in PAL, when using limitNumLabels

python/gui/qgsrubberband.sip

@@ -221,7 +221,7 @@ class QgsRubberBand: QgsMapCanvasItem
      * Returns the rubberband as a Geometry.
      *  @return A geometry object which reflects the current state of the rubberband.
      */
-    QgsGeometry* asGeometry();
+    QgsGeometry asGeometry() const;
 
     virtual void updatePosition();
 

src/analysis/interpolation/DualEdgeTriangulation.cc

@@ -3138,9 +3138,7 @@ bool DualEdgeTriangulation::saveAsShapefile( const QString& fileName ) const
       QgsPolyline lineGeom;
       lineGeom.push_back( QgsPoint( p1->getX(), p1->getY() ) );
       lineGeom.push_back( QgsPoint( p2->getX(), p2->getY() ) );
-      QgsGeometry* geom = QgsGeometry::fromPolyline( lineGeom );
-      edgeLineFeature.setGeometry( *geom );
-      delete geom;
+      edgeLineFeature.setGeometry( QgsGeometry::fromPolyline( lineGeom ) );
       edgeLineFeature.initAttributes( 1 );
 
       //attributes

src/analysis/openstreetmap/qgsosmdatabase.cpp

@@ -410,7 +410,7 @@ void QgsOSMDatabase::exportSpatiaLiteNodes( const QString& tableName, const QStr
     if ( skipNull )
       continue;
 
-    QgsGeometry* geom = QgsGeometry::fromPoint( n.point() );
+    QgsGeometry geom = QgsGeometry::fromPoint( n.point() );
     int col = 0;
     sqlite3_bind_int64( stmtInsert, ++col, n.id() );
 
@@ -423,19 +423,17 @@ void QgsOSMDatabase::exportSpatiaLiteNodes( const QString& tableName, const QStr
         sqlite3_bind_null( stmtInsert, ++col );
     }
 
-    sqlite3_bind_blob( stmtInsert, ++col, geom->asWkb(), ( int ) geom->wkbSize(), SQLITE_STATIC );
+    sqlite3_bind_blob( stmtInsert, ++col, geom.asWkb(), ( int ) geom.wkbSize(), SQLITE_STATIC );
 
     int insertRes = sqlite3_step( stmtInsert );
     if ( insertRes != SQLITE_DONE )
     {
       mError = QString( "Error inserting node %1 [%2]" ).arg( n.id() ).arg( insertRes );
-      delete geom;
       break;
     }
 
     sqlite3_reset( stmtInsert );
     sqlite3_clear_bindings( stmtInsert );
-    delete geom;
   }
 
   sqlite3_finalize( stmtInsert );
@@ -492,7 +490,7 @@ void QgsOSMDatabase::exportSpatiaLiteWays( bool closed, const QString& tableName
     if ( skipNull )
       continue;
 
-    QgsGeometry* geom = closed ? QgsGeometry::fromPolygon( QgsPolygon() << polyline ) : QgsGeometry::fromPolyline( polyline );
+    QgsGeometry geom = closed ? QgsGeometry::fromPolygon( QgsPolygon() << polyline ) : QgsGeometry::fromPolyline( polyline );
     int col = 0;
     sqlite3_bind_int64( stmtInsert, ++col, w.id() );
 
@@ -505,22 +503,20 @@ void QgsOSMDatabase::exportSpatiaLiteWays( bool closed, const QString& tableName
         sqlite3_bind_null( stmtInsert, ++col );
     }
 
-    if ( geom )
-      sqlite3_bind_blob( stmtInsert, ++col, geom->asWkb(), ( int ) geom->wkbSize(), SQLITE_STATIC );
+    if ( !geom.isEmpty() )
+      sqlite3_bind_blob( stmtInsert, ++col, geom.asWkb(), ( int ) geom.wkbSize(), SQLITE_STATIC );
     else
       sqlite3_bind_null( stmtInsert, ++col );
 
     int insertRes = sqlite3_step( stmtInsert );
     if ( insertRes != SQLITE_DONE )
     {
       mError = QString( "Error inserting way %1 [%2]" ).arg( w.id() ).arg( insertRes );
-      delete geom;
       break;
     }
 
     sqlite3_reset( stmtInsert );
     sqlite3_clear_bindings( stmtInsert );
-    delete geom;
   }
 
   sqlite3_finalize( stmtInsert );