Provided by: libgeo-point-perl_0.98-1_all bug

NAME

       Geo::Point - a point on the globe

INHERITANCE

        Geo::Point
          is a Geo::Shape

SYNOPSIS

        use Geo::Point;

        my $p = Geo::Point->latlong(1,2);
        my $p = Geo::Point->longlat(2,1);

        my $w = Geo::Proj->new(wgs84 => ...);
        my $p = Geo::Point->latlong(1,2, 'wgs84');

        my ($lat, $long) = $p->latlong;
        my ($x, $y) = $p->xy;
        my ($x, $y) = $p->in('utm31-wgs84');

        my $p = Geo::Point->xy(1,2);

DESCRIPTION

       One location on the globe, in any coordinate system.  This package tries to hide the maths
       and the coordinate system in which the point is represented.

       One of the most confusing things when handling geometrical data, is that sometimes
       latlong, sometimes xy are used: horizontal and vertical organization reversed.  This
       package tries to hide this from your program by providing abstract accessors latlong(),
       longlat(), xy(), and yx().

       Extends "DESCRIPTION" in Geo::Shape.

METHODS

       Extends "METHODS" in Geo::Shape.

   Constructors
       Extends "Constructors" in Geo::Shape.

       Geo::Point->fromString( $string, [$projection] )
           Create a new point from a $string.  The coordinates can be separated by a comma
           (preferably), or blanks.  When the coordinates end on NSEW, the order does not matter,
           otherwise lat-long or xy order is presumed.

           This routine is very smart.  It understands:

             PROJLABEL VALUE VALUE
             PROJLABEL: VALUE VALUE
             PROJLABEL, VALUE, VALUE
             PROJLABEL: VALUE, VALUE
             VALUE VALUE
             VALUE, VALUE
             utm: ZONE, VALUE, VALUE   # also without commas and ':'
             utm: VALUE, VALUE, ZONE   # also without commas and ':'
             utm: VALUE, VALUE         # also without commas and ':'
             ZONE, VALUE, VALUE        # also without commas and ':'
             VALUE, VALUE, ZONE        # also without commas and ':'

           The VALUE must be suitable for projection.  If only two values are provided, a "d",
           single or double quote, or trailing/leading "e", "w", "n", "s" (either lower or upper-
           case) will force a latlong projection.  Those coordinates must follow the rules of
           dms2deg().

           example: point from string

            my $x = 'utm 31n 12311.123 34242.12'; # utm zone 31N
            my $x = '12311.123 34242.12 31';      # utm zone 31
            my $x = '123.123E 12.34';             # wgs84  latlong
            my $x = 'clrk66 123.123 12.34';       # clrk66 latlong
            my $x = '12d34'123.1W 11.1123';       # wgs84  longlat

            my $p = Geo::Point->fromString($x);

            # When parsing user applications, you probably want:
            my $p = eval { Geo::Point->fromString($x) };
            warn $@ if $@;

       $obj->latlong( [ $lat,$long,[$proj] ] | [$proj] )
       Geo::Point->latlong( [ $lat,$long,[$proj] ] | [$proj] )
           When called as class method, you create a new point.  Provide a LATitude and
           LONGitude. The optional PROJection tells in which coordinate system.

           As instance method, the latitude and longitude are reported.  You can ask it to be
           translated into the $proj coordinate system first.

           When $proj is undefined, none is presumed. The project must be specified as string,
           which referse to a projection defined by Geo::Proj.  See also longlat(), xy(), and
           yx().

           example: latlong as class method

            my $wgs84 = Geo::Proj->new(wgs84 => ...);
            my $gp    = Geo::Point->latlong(52.3213, 5.53, 'wgs84');

           example: latlong as instance method

            my ($lat, $long) = $gp->latlong('wgs84');

       $obj->longlat( [ $long,$lat,[$proj] ] | [$proj] )
       Geo::Point->longlat( [ $long,$lat,[$proj] ] | [$proj] )
           Like latlong(), but with the coordinates reversed.  Some applications prefer this.

       $obj->new(%options)
       Geo::Point->new(%options)
            -Option   --Defined in     --Default
             lat                         undef
             latitude                    undef
             long                        undef
             longitude                   undef
             proj       Geo::Shape       see Geo::Proj::defaultProjection()
             x                           undef
             y                           undef

           lat => COORDINATE
           latitude => COORDINATE
           long => COORDINATE
           longitude => COORDINATE
           proj => LABEL
           x => COORDINATE
           y => COORDINATE
       $obj->xy( [$x, $y, [$proj] ] | [$proj] )
       Geo::Point->xy( [$x, $y, [$proj] ] | [$proj] )
           Like longlat() but now for carthesian projections.  Usually, the coordinate order is
           reversed.  See also yx().

       $obj->yx( [$y, $x, [$proj] ] | [$proj] )
       Geo::Point->yx( [$y, $x, [$proj] ] | [$proj] )
           Like latlong() but now for carthesian projections.  Usually, the coordinate order is
           reversed.  See also xy().

   Attributes
       Extends "Attributes" in Geo::Shape.

       $obj->proj()
           Inherited, see "Attributes" in Geo::Shape

       $obj->proj4()
           Inherited, see "Attributes" in Geo::Shape

   Accessors
       The accessors only work correctly when you are sure that the point is in the right
       coordinate systems.

       $obj->lat()
       $obj->latitude()
       $obj->long()
       $obj->longitude()
       $obj->x()
       $obj->y()

   Projections
       Extends "Projections" in Geo::Shape.

       $obj->in( <$label|'utm'> )
           Inherited, see "Projections" in Geo::Shape

       $obj->normalize()
           Be sure the that coordinates are between -180/180 longitude, -90/90 lattitude.  No
           changes for non-latlong projections.

       $obj->projectOn($nick, @points)
           Inherited, see "Projections" in Geo::Shape

   Geometry
       Extends "Geometry" in Geo::Shape.

       $obj->area()
           Always returns zero.

       $obj->bbox()
           The bounding box of a point contains twice itself.

       $obj->bboxCenter()
           Inherited, see "Geometry" in Geo::Shape

       $obj->bboxRing( [$xmin, $ymin, $xmax, $ymax, [$proj]] )
       Geo::Point->bboxRing( [$xmin, $ymin, $xmax, $ymax, [$proj]] )
           Inherited, see "Geometry" in Geo::Shape

       $obj->distance( $object, [$unit] )
           Inherited, see "Geometry" in Geo::Shape

       $obj->distancePointPoint($geodist, $units, $point)
           Compute the distance between the current point and some other $point in $units.  The
           $geodist object will do the calculations.  See distance().

       $obj->inBBox($object)
           Returns a true value if this point is inside the bounding box of the specified
           $object.  The borders of the bbox are included.  This is relatively fast to check,
           even for complex objects.  When the projections differ, the point is translated into
           the $object's coordinate system, because that one must stay square.

       $obj->perimeter()
           Always returns zero.

       $obj->sameAs($other, $tolerance)

   Display
       Extends "Display" in Geo::Shape.

       $obj->coords()
           Returns the coordinates in their usual order, formatted as string with a joining
           blank;

       $obj->coordsUsualOrder()
           Returns the coordinates in the order which is usual for the projection used.

       $obj->deg2dm($degrees, $pos, $neg)
       Geo::Point->deg2dm($degrees, $pos, $neg)
           Inherited, see "Display" in Geo::Shape

       $obj->deg2dms($degrees, $pos, $neg)
       Geo::Point->deg2dms($degrees, $pos, $neg)
           Inherited, see "Display" in Geo::Shape

       $obj->dm( [$projection] )
           Like dms(), but doesn't show seconds.

       $obj->dmHTML( [$projection] )
           Like dmsHTML(), but does not show seconds.

       $obj->dms( [$projection] )
           Show the point as DMS value-pair.  You must be sure that the coordinate is a
           projection for which is it useful to represent the values in DMS.  In SCALAR context,
           one string is returned.  In LIST context, the values are returned separately in
           latlong order.

           Be warned, that the returned string may contain single and double quote characters,
           which may confuse HTML (see dmsHTML()).

       $obj->dms2deg($dms)
       Geo::Point->dms2deg($dms)
           Inherited, see "Display" in Geo::Shape

       $obj->dmsHTML( [$projection] )
           Like dms(), but all character which are troublesome for HTML are translated into
           character codes.

       $obj->moveWest()
           Move a point from the eastern calculations into the western calculations, resulting in
           a value below -180.  This is useful when this point is part of a larger construct,
           like the corners of a satellite image, which are both sides of the -180 meridian.

           example: moving West

            my $point = Geo::Point->latlong(24, 179);
            $point->moveWest;
            print $point->long;   # -181;

       $obj->toString( [$projection] )
           Returns a string representation of the point, which is also used for stringification.
           The default projection is the one of the point.

           example:

            print "Point: ",$gp->toString, "\n";
            print "Point: $gp\n";   # same

            print "Point: ",$gp->toString('clrk66'), "\n";

OVERLOAD

       Extends "OVERLOAD" in Geo::Shape.

       overload: '""' (stringification)
           Inherited, see "OVERLOAD" in Geo::Shape

       overload: 'bool' (truth value)
           Inherited, see "OVERLOAD" in Geo::Shape

DIAGNOSTICS

       Error: UTM requires 3 values: easting, northing, and zone
       Error: can only compare a point to another Geo::Point
       Error: distance calculation not implemented between a $kind and a $kind
           Only a subset of all objects can be used in the distance calculation.  The limitation
           is purely caused by lack of time to implement this.

       Error: dms latitude coordinate not understood: $string
           See dms2deg() for permitted formats.

       Error: dms longitude coordinate not understood: $string
           See dms2deg() for permitted formats.

       Error: illegal UTM zone in $string
           A UTM zone can be detected at the beginning or at the end of the input.  It contains a
           number (from 1 up to 60) and an optional latitude indication (C up to X, except I and
           O).

       Error: illegal character in x coordinate $x
       Error: illegal character in y coordinate $y
       Error: in() not implemented for a $class
       Error: too few values in $string (got @parts)
           Most projection require two parameters, but utm requires three (with zone).

       Error: too many values in $string (got @parts)
           Most projection require two parameters, but utm requires three (with zone).

       Error: undefined projection $proj for $string
           The projection you used (or is set as default) is not defined.  See Geo::Proj::new()
           about how to defined them.

SEE ALSO

       This module is part of Geo-Point distribution version 0.98, built on February 01, 2019.
       Website: http://perl.overmeer.net/CPAN/

LICENSE

       Copyrights 2005-2019 by [Mark Overmeer]. For other contributors see ChangeLog.

       This program is free software; you can redistribute it and/or modify it under the same
       terms as Perl itself.  See http://dev.perl.org/licenses/