ROAD(7) ROAD(7)
NAME
road, gps - road map of the United States
SYNOPSIS
games/road [ -g ] [ -s scale ]
games/gps
DESCRIPTION
Road displays a road map centered around some specified
place in the United States. The data comes from the Census
Bureau Tiger Database. The map is drawn in three shades of
grey. Light grey is used for water features such as rivers,
streams and lakes. Dark grey is used for railroads and air-
ports. Black is used for roads. On terminals with ldepth
zero, all shades appear black.
Without options, the center of the map is the latitude and
longitude specified in the file /lib/sky/here. If the -g
option is given, the center of the map will be the latitude
and longitude specified by continually monitoring the end of
the file /tmp/gpslog. This file is written by the GPS
satellite receiver program gps. With this option, and with
gps running, road becomes a moving map display suitable for
cars or planes.
Keyboard commands
s number
sets the scale of the map to number. The number can be
prefixed with + or - to increase/decrease the current
scale. Scale 6 is about one mile across the screen and
scale 10 is about ten miles across. Scales 1 through
10 are drawn with maximum detail showing all roads,
trails, rivers, streams and airports. Scales 11
through 14 show highways, rivers, airports and county
boundaries. Scales 15 through 20 show interstate high-
ways and state boundaries.
/regexp
All features labeled by text matching the regular
expression are highlighted.
p place
centers the map at the specified place. Usually the
place must have the associated state code, (eg
murrayhill,nj) but places like lax and ewr are also
known.
l latitude longitude
centers the map at the specified coordinate.
Page 1 Plan 9 (printed 12/16/25)
ROAD(7) ROAD(7)
g toggles the -g option described above.
q Exit.
Mouse button commands
Button 1
displays the text of the line nearest the cursor. Nor-
mally this is the name of a street or river.
Button 2
displays the text of the place nearest the cursor.
Normally this is a town.
Button 3
centers the display on the cursor position.
Gps reads /dev/eia0 assumed connected to a Garmin GPS-55
satellite receiver and writes the current location on the
end of the file /tmp/gpslog. It is intended to be used with
mobile PC's.
FILES
/lib/roads/LLLL/LLLLGGGG.h
scale 1-10 database files where LLLL is the latitude
multiplied by 5 and GGGG is the longitude multiplied by
5.
/lib/roads/LLL/LLLGGG.h
scale 11-14 database files where LLL is the latitude
multiplied by 1 and GGG is the longitude multiplied by
1.
/lib/roads/LL/LLGG.h
scale 15-20 database files where LL is the latitude
multiplied by 0.2 and GG is the longitude multiplied by
0.2.
/lib/roads/place
/lib/roads/place.local are the translations between
place names and locations. These files must be sorted.
/lib/sky/here
default starting map center.
/tmp/gpslog
moving map location.
SOURCE
/sys/src/games/road
/sys/src/games/gps
Page 2 Plan 9 (printed 12/16/25)