Polygon Generation via Intersection

Subcatchments, existing polygons and polygons from GIS sources may be intersected to generate a new set of polygons. Polygons from a single source or from a number of different sources may be intersected.

The original polygons are divided so that each overlap area becomes a single separate polygon. (Note that the original polygons are not overwritten).

Thinning tools are available to enable you to clean the data allowing improvements in performance time and reducing the size of data generated.

The method of carrying out Polygon Generation via Intersection and the results produced are best demonstrated as an example:

Intersect Polygons Example

In this example, a network subcatchment and a GIS polygon representing a road overlap one another. Intersection is carried out, resulting in the creation of five new polygons.

Overlapping Network Subcatchment and GIS Road Polygon

  1. Select Geometry | Polygon generation via intersection from the Model menu. This displays the Polygon Generation via Intersection Dialog.
  2. From the Polygon Generation via Intersection Dialog:
  3. Click Intersect

Five new polygons are created:

New Set of Polygons Created by Intersecting Polygons


A log is produced including details of time taken for polygon creation and the number of vertices and edges created.

The Log will also show error messages and warning messages.

The log is saved temporarily in the Local Working Folder as an html file. When the log is closed in InfoWorks ICM, the log file in the Local Working Folder will be removed. To view the log at a later date, save the file in the Local Working Folder to another directory and/or under a different name.

Advanced Polygon and Polyline Editing

Polygon Generation via Intersection Dialog