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>From: Stacy Brodzik <address@hidden> >Organization: UCAR/Unidata >Keywords: 200103130136.f2D1aFL24036 >I recently saw a garp display of most of Oregon that looked like it >had the major roads overlaid on the rest of the data. Is there a roads >overlay file? If so, where in the gempak filetree would I find it? > >Thanks for your time. > >Stacy > > > >-- >Stacy Brodzik INTERNET: address@hidden > >University of Washington >Dept of Atmospheric Sciences >Box 351640 >Seattle, WA 98195-1640 > Stacy, GEMPAK does come with map databases for Interstates, US highways, State Highways and major arterials. Garp is configured to turn these maps on automatically when you have zoomed in to a certain domain size. The road map data bases are: NWS supplied: loisus.nws loshus.nws louhus.nws lordus.nws Unidata additions: rdis.uni rdus.uni rdsh.uni rdar.uni The files are from the same sources, but the .uni mapfiles are larger since they are created at a higher resolution. The default in $GARPHOME/tables/maplist.tbl is to use the rdxx.uni maps when the map area is less than 3 degrees. You can modify this interactively from the Garp "options" menu, which has the puldown for "map backgrounds". Once you have the map widget displayed, you can scroll down to the roads section. You can modify the line color, type, style, as well as the resolution when the map is turned on (eg 3.0 is the default) and turned off (0 is the default). An example in maplist.tbl for using the lower resolution map files for coarser displays and higher resolution maps for finer displays would look like: ! Byways ! Interstate Hwys rdis.uni yes 3.0 0.0 2 1 2 State Hwys rdsh.uni yes 3.0 0.0 23 1 1 US Hwys rdus.uni yes 3.0 0.0 22 1 2 Major Arterials rdar.uni yes 3.0 0.0 23 1 1 ! NWS Interstates loisus.nws no 90.0 3.1 2 1 2 NWS US Hwys louhus.nws no 20.0 3.1 22 1 2 NWS State Hwys loshus.nws no 20.0 3.1 23 1 1 NWS Roads lordus.nws no 5.0 3.1 23 1 1 Of course, you can use any of these maps in the other gempak programs as well using the $MAPFIL program variable. For more information on the map data bases, see the gempak online help for mapfil, eg "phelp mapfil". Steve Chiswell Unidata User Support