QgsFeature and QgsGeometry serialization

qgis · May 18, 2015 · 6e3cbe3 · 6e3cbe3
1 parent e633caf
commit 6e3cbe3
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Showing 4 changed files with 61 additions and 0 deletions.
diff --git a/src/core/qgsfeature.cpp b/src/core/qgsfeature.cpp
@@ -252,3 +252,32 @@ int QgsFeature::fieldNameIndex( const QString& fieldName ) const
   }
   return -1;
 }
+
+QDataStream& operator<<( QDataStream& out, const QgsFeature& feature )
+{
+  out << feature.id();
+  out << feature.attributes();
+  if ( feature.geometry() )
+  {
+    out << *( feature.geometry() );
+  }
+  else
+  {
+    QgsGeometry geometry;
+    out << geometry;
+  }
+  out << feature.isValid();
+  return out;
+}
+
+QDataStream& operator>>( QDataStream& in, QgsFeature& feature )
+{
+  QgsFeatureId id;
+  QgsGeometry* geometry = new QgsGeometry();
+  bool valid;
+  in >> id >> feature.attributes() >> *geometry >> valid;
+  feature.setFeatureId( id );
+  feature.setGeometry( geometry );
+  feature.setValid( valid );
+  return in;
+}
diff --git a/src/core/qgsfeature.h b/src/core/qgsfeature.h
@@ -64,6 +64,11 @@ class QgsFeatureId
     friend uint qHash( const QgsFeatureId &id );
 };
 
+/** Writes the feature id to stream out. QGIS version compatibility is not guaranteed. */
+CORE_EXPORT QDataStream& operator<<( QDataStream& out, const QgsFeatureId& featureId );
+/** Reads a feature id from stream in into feature id. QGIS version compatibility is not guaranteed. */
+CORE_EXPORT QDataStream& operator>>( QDataStream& in, QgsFeatureId& featureId );
+
 inline uint qHash( const QgsFeatureId &id )
 {
   return qHash( id.mId );
@@ -313,6 +318,11 @@ class CORE_EXPORT QgsFeature
 
 }; // class QgsFeature
 
+/** Writes the feature to stream out. QGIS version compatibility is not guaranteed. */
+CORE_EXPORT QDataStream& operator<<( QDataStream& out, const QgsFeature& feature );
+/** Reads a feature from stream in into feature. QGIS version compatibility is not guaranteed. */
+CORE_EXPORT QDataStream& operator>>( QDataStream& in, QgsFeature& feature );
+
 // key = feature id, value = changed attributes
 typedef QMap<QgsFeatureId, QgsAttributeMap> QgsChangedAttributesMap;
 

diff --git a/src/core/qgsgeometry.cpp b/src/core/qgsgeometry.cpp
@@ -6781,3 +6781,20 @@ bool QgsGeometry::compare( const QgsMultiPolygon &p1, const QgsMultiPolygon &p2,
   }
   return true;
 }
+
+QDataStream& operator<<( QDataStream& out, const QgsGeometry& geometry )
+{
+  QByteArray byteArray = QByteArray::fromRawData(( char * )geometry.asWkb(), geometry.wkbSize() ); // does not copy data and does not take ownership
+  out << byteArray;
+  return out;
+}
+
+QDataStream& operator>>( QDataStream& in, QgsGeometry& geometry )
+{
+  QByteArray byteArray;
+  in >> byteArray;
+  char *data = new char[byteArray.size()];
+  memcpy( data, byteArray.data(), byteArray.size() );
+  geometry.fromWkb(( unsigned char* )data, byteArray.size() );
+  return in;
+}
diff --git a/src/core/qgsgeometry.h b/src/core/qgsgeometry.h
@@ -721,6 +721,11 @@ class CORE_EXPORT QgsGeometry
 
 Q_DECLARE_METATYPE( QgsGeometry );
 
+/** Writes the geometry to stream out. QGIS version compatibility is not guaranteed. */
+CORE_EXPORT QDataStream& operator<<( QDataStream& out, const QgsGeometry& geometry );
+/** Reads a geometry from stream in into geometry. QGIS version compatibility is not guaranteed. */
+CORE_EXPORT QDataStream& operator>>( QDataStream& in, QgsGeometry& geometry );
+
 class CORE_EXPORT QgsWkbPtr
 {
     mutable unsigned char *mP;