This dialog allows you to change parameters which effect the point spacing and closing distance. This dialog is activated from the Digitizing - Digitizing Options - Digitizing Parameters.
This parameter controls the minimum spacing between points. Enter the minimum distance between points in mm. (as measured on the paper). The project distance between points will depend on the map scale.
This parameter is useful when digitizing a closed boundary. An audible sound noise is made when the user gets close (closer than the specified distance) to the starting point of the feature.