code: public void onCoordinateSnapAttempt(CoordinateSnapEvent event) {
  		if (editingService.getEditingState() == GeometryEditState.INSERTING) {
  			String identifier = baseName + "."
  					+ editingService.getIndexService().format(editingService.getInsertIndex());
  			Object parentGroup = groups.get(identifier.substring(0, identifier.lastIndexOf('.')) + ".vertices");
  
  			Coordinate temp = event.getTo();
  			Coordinate coordinate = mapWidget.getMapModel().getMapView().getWorldViewTransformer().worldToPan(temp);
  			addShapeToGraphicsContext(mapWidget.getVectorContext(), parentGroup, identifier, coordinate,
  					event.hasSnapped() ? styleService.getVertexSnappedStyle() : new ShapeStyle());
  		}
  	}
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