OpenLayers Polygon Hole Digitizing

# Drawing Holes in Polygons

draw polygon hole

The DrawFeature control can be used to digitize donut polygons.

- navigate
- draw polygon

To digitize holes in polygons, hold down the `Alt` key and draw over an existing polygon. By default, the `Shift` key triggers freehand drawing. Use a combination of the `Shift` and `Alt` keys to digitize holes in freehand mode.

See the donut.js source for details on how this is done.