Create a difference polygon

Available with Production Mapping license.

Available with Defense Mapping license.

If you are creating polygons of land uses, soils, counties, or property ownership, for example, you often need to create polygons next to one another. The polygons should share a border, but you want to avoid digitizing the border twice or having overlaps or spaces between polygons. You can use the Difference Polygon construction tool when creating new polygons to help ensure that your data forms a continuous fabric. With the Difference Polygon tool, you can digitize polygons that adjoin existing polygons using the existing polygons' geometry and the edit sketch to define the edges of the new polygons.

The Difference Polygon construction tool is similar to the Auto-Complete Polygon tool. However, the Difference Polygon tool allows you to create polygons that are coincident to polygons in any layer, not just polygons from the same layer.

A difference polygon created over two other polygon features

1. Add polygon layers to your map, if they don't already exist, by dragging polygon feature data from the Catalog pane onto the map.

   A feature template for the new layer is autogenerated with default settings.

   Tip:

   If the feature data does not exist, right-click the target geodatabase in the Catalog pane and create a new feature class.

2. On the Edit tab, in the Features group, click Create .

   The Create Features pane appears.

3. In the Create Features pane, click a polygon feature template.

   The template expands to show the tool palette.

4. In the Create Features pane, next to the tool palette, click the Forward button to open the Active Template page.

   The tool palette and the feature attribute table appear.

5. In the attribute table, type the values you want to apply to the new feature.

   For group templates, click a template icon to display its attribute table.

6. On the Edit tab, in the Snapping group, enable your snapping preferences.
7. In the Active Template page, click Difference Polygon .
8. Click the map, drag the pointer, and double-click the end node to finish the polygon.

   Tip:

   • If the polygon you created doesn't overlap any preexisting polygons, the edit sketch will be used to define the edges of the new polygon.
   • All the polygons you draw on the map are separate and will not merge with the others you draw.