Monday, February 14, 2011

Removing holes from polygons with Global Mapper

Sometimes I want to remove the holes inside polygons. Global Mapper provides a convenient function to do the job. Here are the steps that I use:

  1. Start up Global Mapper. Load in a polygon with holes.

    The polygon is loaded.

  2. On the keyboard, press ALT+D to activate the Digitizer Tool.

    The cursor changes to a cross hair with the Edit label.
  3. Click on the polygon.

    The polygon is selected.

  4. Mouse right click anywhere inside the map window.

    A pop up menu appears.

  5. Choose Advanced Selection Options | Select Island Areas in Selected Area Feature.

    All the holes are selected.
  6. Mouse right click anywhere inside the map window.

    A pop up menu appears.

  7. Choose Delete Selected Features.

    The holes are deleted.

1 comment:

Robert R. said...

Nice. It helps, I agree, but if you have another area within the selected one, it selects that feature as well, even if that is not a hole.
Furthermore, If you want to do this (remove the holes)for an entire shapefile layer (area) it does not work.