Merge pull request #3349 from nyalldawson/feature_geom

Mega API break - fix QgsFeature geometry getters/setters

Author: nyalldawson

doc/api_break.dox

@@ -224,12 +224,50 @@ attributeIndexes(), pkAttributeIndexes(), isSaveAndLoadStyleToDBSupported()</li>
 </li>
 </ul>
 
+\subsection qgis_api_break_3_0_QgsFeature QgsFeature
+
+<ul>
+<li>geometryAndOwnership() has been removed. Use geometry() instead.</li>
+<li>setGeometryAndOwnership() has been removed. Use setGeometry() instead.</li>
+<li>The setGeometry( QgsGeometry* ) method has been removed, use setGeometry( const QgsGeometry& ) instead.</li>
+<li>The geometry() method now returns a copy of the geometry, not a pointer. Since QgsGeometry objects are
+implicitly shared this is a low-cost copy, and avoids ownership and dangling pointer issues. <b>Very important: Testing that
+a feature has a geometry is now done using the new hasGeometry() method. Any code which compares QgsFeature::geometry() to 
+None will need to be modified, as the method will return an empty geometry if the feature has no geometry.</b></li>
+<li>The temporary constGeometry() method has been removed. Use geometry() instead.</li>
+<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. The biggest impact with this change is that PyQGIS code should not compare a geometry
+result to None, but instead either use a boolean test (`if g.buffer(10):`) or explicitly use the isEmpty()
+method to determine if a geometry is valid.</li>
+</ul>
+
+\subsection qgis_api_break_3_0_QgsGeometryAnalyzer QgsGeometryAnalyzer
+
+<ul>
+<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
 
 <ul>
 <li>QgsGroupWMSDataDialo has been renamed to QgsGroupWmsDataDialog</li>
 </ul>
 
+\subsection qgis_api_break_3_0_QgsHighlight QgsHighlight
+
+<ul>
+<li>The QgsHighlight constructor now takes a geometry reference, not a pointer.</li>
+</ul>
+
+
+
 \subsection qgis_api_break_3_0_QgsVectorDataProvider QgsVectorDataProvider
 
 <ul>
@@ -239,6 +277,7 @@ only affects third party c++ providers, and does not affect PyQGIS scripts.</li>
 <li>The SaveAsShapefile, SelectGeometryAtId, RandomSelectGeometryAtId and SequentialSelectGeometryAtId
 capabilities have been removed, as they were unused and had no effect.</li>
 <li>capabilities() now returns a typesafe QgsVectorDataProvider::Capabilities object, not an integer.</li>
+<li>convertToProviderType() now takes a geometry reference, not a pointer.</li>
 </ul>
 
 \subsection qgis_api_break_3_0_QgsLabelingEngineInterface QgsLabelingEngineInterface
@@ -334,6 +373,7 @@ be returned instead of a null pointer if no transformation is required.</li>
 
 <ul>
 <li>init(QgsMapRenderer*) has been removed. Use init(const QgsMapSettings&) instead.</li>
+<li>prepareGeometry and geometryRequiresPreparation now take geometry references, not pointers.</li>
 </ul>
 
 \subsection qgis_api_break_3_0_QgsOSMElement QgsOSMElement
@@ -396,6 +436,12 @@ be returned instead of a null pointer if no transformation is required.</li>
 <li>setCoordinateTransform() now takes a QgsCoordinateTransform reference, not a pointer. An invalid QgsCoordinateTransform should be used instead of a null pointer if no transformation is required.</li>
 </ul>
 
+\subsection qgis_api_break_3_0_QgsRubberBand QgsRubberBand
+
+<ul>
+<li>setToGeometry() and addGeometry() now take geometry references, not pointers.</li>
+</ul>
+
 \subsection qgis_api_break_3_0_QgsPalLayerSettings QgsPalLayerSettings
 
 <ul>
@@ -430,6 +476,23 @@ plugins calling this method will need to be updated.</li>
 setExcludeAttributesWms()</li>
 <li>excludeAttributesWFS() and setExcludeAttributesWFS() have been renamed to excludeAttributesWfs() and 
 setExcludeAttributesWfs()</li>
+<li>changeGeometry() now accepts a geometry reference, not a pointer.</li>
+<li>The geometryChanged() signal now uses a const QgsGeometry reference.</li>
+<li>The deprecated removePolygonIntersections has been removed.</li>
+<li>addTopologicalPoints() now takes a geometry reference, not a pointer.</li> 
+</ul>
+
+\subsection qgis_api_break_3_0_QgsVectorLayerEditBuffer QgsVectorLayerEditBuffer
+
+<ul>
+<li>changeGeometry() now accepts a geometry reference, not a pointer.</li>
+<li>The geometryChanged() signal now uses a const QgsGeometry reference.</li>
+</ul>
+
+\subsection qgis_api_break_3_0_QgsVectorLayerEditUtils QgsVectorLayerEditUtils
+
+<ul>
+<li>addTopologicalPoints() now accepts a geometry reference, not a pointer.</li>
 </ul>
 
 \subsection qgis_api_break_3_0_QgsVectorLayerImport QgsVectorLayerImport
@@ -441,6 +504,13 @@ pointers makes for more robust, safer code. Use an invalid (default constructed)
 in code which previously passed a null pointer to QgsVectorLayerImport.</li>
 </ul>
 
+\subsection qgis_api_break_3_0_QgsVectorLayerUndoCommand QgsVectorLayerUndoCommand
+
+<ul>
+<li>QgsVectorLayerUndoCommandChangeGeometry constructor now accepts a geometry reference, not a pointer.</li>
+</ul>
+
+
 \subsection qgis_api_break_3_0_QgsPointLocator QgsPointLocator
 
 <ul>

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/__init__.py

@@ -29,6 +29,14 @@
 import string
 from qgis._core import *
 
+# Boolean evaluation of QgsGeometry
+
+
+def _geometryNonZero(self):
+    return not self.isEmpty()
+QgsGeometry.__nonzero__ = _geometryNonZero
+QgsGeometry.__bool__ = _geometryNonZero
+
 
 def register_function(function, arg_count, group, usesgeometry=False, referenced_columns=[QgsFeatureRequest.AllAttributes], **kwargs):
     """

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.
@@ -393,49 +393,57 @@ class QgsGeometry
      */
     int makeDifference( const QgsGeometry* other );
 
+    /** Returns the geometry formed by modifying this geometry such that it does not
+     * intersect the other geometry.
+     * @param other geometry that should not be intersect
+     * @return difference geometry, or empty geometry if difference could not be calculated
+     * @note added in QGIS 3.0
+     */
+    QgsGeometry makeDifference( const QgsGeometry& other ) const;
+
     /** Returns the bounding box of this feature*/
     QgsRectangle boundingBox() const;
 
     /** Test for intersection with a rectangle (uses GEOS) */
     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
@@ -446,44 +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.
@@ -495,10 +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 );
@@ -523,7 +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 */
 
@@ -556,7 +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.
@@ -635,7 +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
@@ -696,15 +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
@@ -760,7 +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;
@@ -786,5 +794,11 @@ class QgsGeometry
     //! Allows direct construction of QVariants from geometry.
     operator QVariant() const;
 
+    /** Returns true if the geometry is non empty (ie, isEmpty() returns false),
+     * or false if it is an empty, uninitialised geometry (ie, ieEmpty() returns true).
+     * @note added in QGIS 3.0
+     */
+    operator bool() const;
+
 }; // class QgsGeometry