2.35. Temporal polygons from lines and points

The tool creates polygons that reflect the state of the area at a particular point in time. Polygons are formed from a set of polylines, each of which is characterized by the start and end dates of its existence. Attributes for polygons are assigned from a layer of points, which also has a time reference.

In addition, grouping of polygon identifiers by a given parameter is carried out by creating a separate field with an ID common to each group (its minimum value). The geometry of the polygons does not change.


  • gis_url - address of the used Web GIS

  • lines_id - ID of the polyline layer from the used Web GIS

  • points_id - ID of the layer with points from the used Web GIS

  • Requested year - the year for which you want to get a time slice

  • year_field - name of the field where the requested year will be written

  • Result field - a new field where the grouping results will be entered, that is, ID

  • Field with identifiers - a field with unique values in the polyline layer; IDs for grouping are borrowed from it

  • Grouping field - the field by which polygons are grouped


  • a layer with polygons (shapefile) relevant for the given year

Launch tool: https://toolbox.nextgis.com/operation/lines2polygons

Usage example:

What are the borders of Russia for the 1598th year AD?


Pic. 2.26. Sample input data. Layers of polylines and dots


Pic. 2.27. Sample input data. Polyline Layer Attributes Table


Pic. 2.28. An example of the result of a tool