3 map \- digitized map formats
7 are a sequence of structures of the form:
11 signed char patchlatitude;
12 signed char patchlongitude;
32 stands for 16-bit integers and there is no padding within or between
34 Shorts are stored in little-endian order, low byte first.
35 To assure portability,
37 accesses them bytewise.
44 10-degree by 10-degree
45 patch of the earth's surface a segment belongs.
46 Their values range from \-9 to 8 and from \-18 to 17,
47 respectively, and indicate the coordinates of the
48 southeast corner of the patch in units of 10 degrees.
52 points is connected; consecutive segments
53 are not necessarily related.
54 Latitude and longitude
55 are measured in units of 0.0001 radian.
59 differences to the first and succeeding points
60 are measured in units of 0.00001 radian.
61 Latitude is counted positive to the north and
62 longitude positive to the west.
64 The patches are ordered lexicographically by
69 index to the first segment of each patch
72 is kept in an associated file named
74 Each line of an index file contains
80 Both the map file and the index file are ordered by
81 patch latitude and longitude.
85 The data comes from the World Data Bank I and II and
86 U.S. Government sources: the Census Bureau, Geological