implemented QgsGeometry::asGeometryCollection()

git-svn-id: http://svn.osgeo.org/qgis/trunk@10026 c8812cc2-4d05-0410-92ff-de0c093fc19c

python/core/qgsgeometry.sip

@@ -276,5 +276,9 @@ not disjoint with existing polygons of the feature*/
         if wkbType is WKBPolygon, otherwise an empty list */
     QgsMultiPolygon asMultiPolygon();
 
+    /** return contents of the geometry as a list of geometries
+     @note added in version 1.1 */
+    QList<QgsGeometry*> asGeometryCollection();
+
 }; // class QgsGeometry
 

src/core/qgsgeometry.cpp

@@ -5443,3 +5443,39 @@ QgsGeometry* QgsGeometry::symDifference( QgsGeometry* geometry )
   }
   CATCH_GEOS( 0 )
 }
+
+
+QList<QgsGeometry*> QgsGeometry::asGeometryCollection()
+{
+  if ( mGeos == NULL )
+  {
+    exportWkbToGeos();
+    if ( mGeos == NULL )
+      return QList<QgsGeometry*>();
+  }
+ 
+  int type = GEOSGeomTypeId( mGeos );
+  QgsDebugMsg("geom type: "+QString::number(type));
+  
+  if ( type != GEOS_MULTIPOINT &&
+       type != GEOS_MULTILINESTRING &&
+       type != GEOS_MULTIPOLYGON &&
+       type != GEOS_GEOMETRYCOLLECTION )
+  {
+    // we have a single-part geometry
+    return QList<QgsGeometry*>();
+  }
+  
+  int count = GEOSGetNumGeometries( mGeos );
+  QgsDebugMsg("geom count: "+QString::number(count));
+
+  QList<QgsGeometry*> geomCollection;
+  
+  for ( int i = 0; i < count; ++i )
+  {
+    const GEOSGeometry * geometry = GEOSGetGeometryN( mGeos, i );
+    geomCollection.append( fromGeosGeom( GEOSGeom_clone(geometry) ) );
+  }
+
+  return geomCollection;
+}

src/core/qgsgeometry.h

@@ -318,6 +318,10 @@ class CORE_EXPORT QgsGeometry
         if wkbType is WKBPolygon, otherwise an empty list */
     QgsMultiPolygon asMultiPolygon();
 
+    /** return contents of the geometry as a list of geometries
+     @note added in version 1.1 */
+    QList<QgsGeometry*> asGeometryCollection();
+
   private:
     // Private variables