Example: Using Lines to Sub-divide Polygons

You can digitise lines or use existing lines to split polygons into smaller polygons.

In this example, an area covered by a large vegetation polygon will be subdivided by digitising division lines and using the Split operation (see Split).

The large vegetation polygon to be subdivided

  1. Digitise division lines to close off the area you want to split from the larger polygon.

    Digitising the division lines

  2. Select the large polygon.

  3. Open the lower app bar and select Edit > Split.

  4. Select the division lines you digitised earlier.

    Note: Switch to Topology mode if the division lines are difficult to view or select.

  5. Click in the Context bar to confirm the split.

    The polygon is split into two polygons: the area defined by the division lines and the original larger polygon.

    The larger of the two parts keeps the identity of the original feature and is marked as a modification, the other part is created as a new feature with identical properties but a new identifier.

    The polygon split into two