Return to map.5 CVS log

Up to [Research Unix] / researchv10dc / man / man5

Annotation of researchv10dc/man/man5/map.5, revision 1.1.1.1

1.1       root        1: .TH MAP 5
                      2: .CT 1 inst_info graphics
                      3: .SH NAME
                      4: map \- digitized map formats
                      5: .SH DESCRIPTION
                      6: Files used by
                      7: .IR  map (7)
                      8: are a sequence of structures of the form:
                      9: .PP
                     10: .EX
                     11: struct {
                     12:        signed char patchlatitude;
                     13:        signed char patchlongitude;
                     14:        short n;
                     15:        union {
                     16:                struct {
                     17:                        short latitude;
                     18:                        short longitude;
                     19:                } point[n];
                     20:                struct {
                     21:                        short latitude;
                     22:                        short longitude;
                     23:                        struct {
                     24:                                signed char latdiff;
                     25:                                signed char londiff;
                     26:                        } point[\-n];
                     27:                } highres;
                     28:        } segment;
                     29: };
                     30: .EE
                     31: .PP
                     32: Fields
                     33: .L patchlatitude
                     34: and
                     35: .L patchlongitude
                     36: tell to what
                     37: 10-degree by 10-degree
                     38: patch of the earth's surface a segment belongs.
                     39: Their values range from \-9 to 8 and from \-18 to 17,
                     40: respectively, and indicate the coordinates of the
                     41: southeast corner of the patch in units of 10 degrees.
                     42: .PP
                     43: Each segment of
                     44: .RB | n |
                     45: points is connected; consecutive segments
                     46: are not necessarily related.
                     47: Latitude and longitude
                     48: are measured in units of 0.0001 radian.
                     49: If
                     50: .B n
                     51: is negative, then
                     52: differences to the first and succeeding points
                     53: are measured in units of 0.00001 radian.
                     54: Latitude is counted positive to the north and
                     55: longitude positive to the west.
                     56: .PP
                     57: The patches are ordered lexicographically by
                     58: .L patchlatitude
                     59: then
                     60: .LR patchlongitude .
                     61: A printable
                     62: index to the first segment of each patch
                     63: in a file named
                     64: .I data
                     65: is kept in an associated file named
                     66: .IB data .x .
                     67: Each line of an index file contains
                     68: .L patchlatitude,
                     69: .L patchlongitude
                     70: and the byte position
                     71: of the patch
                     72: in the map file.
                     73: Both the map file and the index file are ordered by
                     74: patch latitude and longitude.
                     75: .PP
                     76: Shorts are stored in little-endian order, low byte first, 
                     77: regardless of computer architecture.
                     78: To assure portability,
                     79: .I map
                     80: accesses them bytewise.
                     81: .SH "SEE ALSO"
                     82: .IR map (7), 
                     83: .IR proj (3)

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.