7 Digitizing in GRASS

**Figure 16:** GRASS digitizer: v.digit
$\includegraphics[width=0.75\textwidth]{finalpix/vdigit_attributes.eps}$

The GRASS digitizing tool is v.digit. It has recently been completely rewritten and is now fully graphically based. The buttons should be self-explanatory. To start with a new map, the '-n' flag has to be added (or the button activated in the menu). Then, in the settings menu, a new attribute table can be defined, along with the snapping distance. A background map can optionally be loaded prior to beginning digitizing. Areas (currently) have to be digitized in two parts. Closed areas become green, while topologically invalid features remain red. In this case zooming is recommended to identify the error. Once a feature is digitized, a window pops up so that you can enter attributes for this feature. Figure 16 illustrates the setup.