NAME

Location::GeoTool - Perl extension for Geometry processing

SYNOPSIS

use Location::GeoTool;

my $ret = coordformat($coord,$farg,$targ,$pon);
my ($tlat,$tlon) = dir_dist2point($lat,$lon,$dir,$dis,$datum);
my ($dir,$dis) = point2dir_dist($lat,$lon,$tlat,$tlon,$datum);
my ($tlat,$tlon) = datumchange($lat,$lon,$h,$from,$to);

DESCRIPTION

EXPORT

coordformat
dir_dist2point
point2dir_dist
datumchange

coordformat

Change the format of coordinate.
Standard format is pdddmmssnnn.
(p: plus/minus, d:degree, m:minute, s:second n: micro second)

Usage:
  $ret = coordformat($coord,$farg,$targ,$pon);
Arguments:
  $coord : Original Formatted Coordinate
  $farg  : Original Format ID
  $targ  : Wanted Format ID
  $pon   : On/Off of plus/minus
Return Values:
  $ret   : Wanted Formatted Coordinate
Format ID:
  LG_FMT         : Standard Format (pdddmmssnnn)
  LG_FMT_MAPION  : Mapion URL Format (ddd/mm/ss.nnn)
  LG_FMT_DMSN    : dddmmss.nnn
  LG_FMT_SEC     : Second (ssssss.sss)
  LG_FMT_DEG     : Degree (ddd.dddddddd)
  LG_FMT_RAD     : Radian
  LG_FMT_GPSONE  : ddd.mm.ss.nnn

dir_dist2point

Calcurate a point that has the direction and the distance from 
other point.
Original Version is in JavaScript,
http://williams.best.vwh.net/gccalc.htm
coding by Mr. Ed Williams.

Coordinates format is : pdddmmssnnn

Usage:
  ($tlat,$tlon) = dir_dist2point($lat,$lon,$dir,$dis,$datum);
Arguments:
  $lat   : Latitude
  $lon   : Longitude
  $dir   : Direction (degree, North and East are Positive.)
  $dis   : Distance (m)
  $datum : LG_WGS84, LG_TOKYO
Return Values:
  $tlat  : Latitude of calcurated position
  $tlon  : Longitude of calcurated position

point2dir_dist

Give two points by coordinates, then calcurate distance 
and direction of them.
Original Version is in JavaScript,
http://williams.best.vwh.net/gccalc.htm
coding by Mr. Ed Williams.

Coordinates format is : pdddmmssnnn

Usage:
  ($dir,$dis) = point2dir_dist($lat,$lon,$tlat,$tlon,$datum);
Arguments:
  $lat   : Latitude of From Point
  $lon   : Longitude of From Point
  $tlat  : Latitude of To Point
  $tlon  : Longitude of To Point
  $datum : LG_WGS84, LG_TOKYO
Return Values:
  $dir   : Direction (degree, North and East are Positive.)
  $dis   : Distance (m)

datumchange

Change the coordinate to different datum.
Logic is based on Molodensky method. 
Original Version is Perl CGI
http://member.nifty.ne.jp/Nowral/02_DATUM/Molodensky.html
coding by Nowral.

Coordinates format is : pdddmmssnnn

Usage:
  ($tlat,$tlon,$th) = datumchange($lat,$lon,$h,$from,$to);
Arguments:
  $lat  : Latitude
  $lon  : Longitude
  $h¡¡  : Altitude (cm)
  $from : Original Datum
  $to   : Wanted Datum
Return Values:
  $tlat : Latitude in wanted Datum
  $tlon : Longitude in wanted Datum
  $th¡¡ : Altitude in wanted Datum

DEPENDENCIES

Math::Trig

SEE ALSO

dir_dist2point, dir_dist2point function is based on javascript program could be seen in http://williams.best.vwh.net/gccalc.htm

datumchange and molodensly function is based on perl program could be seen in http://member.nifty.ne.jp/Nowral/02_DATUM/Molodensky.html

Thanks for these site.

Support this module in SpaceTag Inc. web site : http://www.spacetag.jp/

AUTHOR

OHTSUKA Ko-hei, <kotsuka@spacetag.jp>

COPYRIGHT AND LICENSE

Copyright (C) 2003 by SpaceTag INC.,

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.1 or, at your option, any later version of Perl 5 you may have available.