<para>
   Overlay files used by <productname>Geogrid</productname>-Viewer has to be in ASCII format. 
   Make sure you save the files correctly.
</para>
<para>
   Lines or polygons within the <productname>Geogrid</productname>-Viewer (type 3 and 4) will be
   converted to tracks, except they are grouped. In this case GPSBabel creates routes.
</para>
<para>
   During the creation of an overlay file, a circle will be added to each 
   postion of a waypoint or a route.
</para>

<para>
  Sample layout of the ASCII overlay file
  <programlisting format="linespecific">
    [Symbol &lt;number # &gt;]
    Typ=&lt;1=picture,2=Text, 3=line, 4=area, 5=retangle, 6=circle, 7=triangle&gt;
    Group=&lt;1=no group, number &gt; 1=group number&gt;
    Col=&lt;number of the line color&gt;
    Zoom=&lt;1=no zoom, 2=zoom&gt;
    Size=&lt;size can be between 101 and 118&gt;
    Art=&lt;style&gt;
    Punkte=&lt;number of XKoord&gt;
    XKoord0=&lt;decimal X coordinate (Longitude) of the waypoint&gt;
    YKoord0=&lt;decimal Y coordinate (Latitude) of the waypoint&gt;
    [MapLage]
    MapName=Top. Karte 1:50.000 Nieders.
    DimmFc=100
    ZoomFc=&lt;zoom level of the map&gt;
    CenterLat=&lt;map center in decimal Y coordinates&gt;
    CenterLong=&lt;map center in decimal X coordinates of &gt;
    RefOn=0
  </programlisting>
</para>

