Polygon to points

Functionality

The Polygons to points operation creates a point for each polygon in the polygon map. Each point obtains the class name, ID, or value of the corresponding polygon. In this way, polygon label points are created. Optionally, you can also obtain label points for polygons which have no class name, no ID or no value, i.e. for undefined polygons.

Tips:

By creating polygon label points which also contains label points for undefined polygons, you can easily find the polygons which do not yet have a correct class name, ID or value. To check whether there are any undefined polygons, you can open the output point map as a table.
When you want to edit label points of undefined polygons:

Display the polygon map and in the Display Options dialog box of the polygon map, choose Boundaries Only;
Display the point map which contains the polygon labels in the same map window (points for undefined polygons do not appear yet);
In the map window, open the Edit menu, choose Properties and select the point map. In the appearing Point Map Properties dialog box, click the Break Dependency Link button;
In the map window, open the Edit menu, choose Edit Layer and select the point map;
The point editor will be started: all points and their class names, IDs or values will be shown including the label points for undefined polygons;
Now, you can edit the points with the undefined value to a correct class name, ID or value (depending on the domain of the map). All changes are directly stored.
When finished, you can repolygonize the segment map using the updated label point file; the class names, IDs or values found in the label point file will be used to assign class names, IDs or values to polygons.

To obtain the names, IDs or values of polygons as text within polygons, it is advised to create an annotation text object and base it on your polygon map. You can edit font, color, and position of the texts in the Annotation Text editor. For more information, see ILWIS objects : annotation text.

Input map requirements:

No special input map requirements.

Domain and coordinate system of output map:

The output point map uses the same domain as the input polygon map.

The output point map uses the same coordinate system and coordinate boundaries as the input polygon map.