Provided by: libgeo-point-perl_0.94-1_all 
NAME
Geo::Line - a sequence of connected points
INHERITANCE
Geo::Line
is a Geo::Shape
Geo::Line
is a Math::Polygon
SYNOPSIS
my $line = Geo::Line->new(points => [$p1, $p2]);
my $line = Geo::Line->line($p1, $p2);
my $ring = Geo::Line->ring($p1, $p2, $p3, $p1);
my $ring = Geo::Line->ring($p1, $p2, $p3);
my $plane = Geo::Line->filled($p1, $p2, $p3, $p1);
my $plane = Geo::Line->filled($p1, $p2, $p3);
DESCRIPTION
A 2-dimensional sequence of connected points. The points will be forced to use the same
projection.
METHODS
Constructors
Geo::Line->bboxFromString(STRING, {PROJECTION])
Create a square from the STRING. The coordinates can be separated by a comma
(preferrably), 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: <4 coordinates in any order, but with NSEW>
...
example: bbox from string
my $x = '5n 2n 3e e12'; # coordinates in any order
my $x = '5e , 2n, 3n, e12'; # coordinates in any order
my $x = '2.12-23.1E, N1-4'; # stretches
my $x = 'wgs84: 2-5e, 1-8n'; # starts with projection
my $x = 'wgs84: e2d12' -3d, n1, n7d12'34"';
my ($xmin, $ymin, $xmax, $ymax, $proj)
= Geo::Line->bboxFromString($x);
my $p = Geo::Line->ringFromString($x);
# When parsing user applications, you probably want:
my $p = eval { Geo::Line->bboxFromString($x) };
warn $@ if $@;
$obj->filled(POINTS, OPTIONS)
Geo::Line->filled(POINTS, OPTIONS)
The POINTS form a ring() and the filled is part of the geometrical shape.
$obj->line(POINTS, OPTIONS)
Geo::Line->line(POINTS, OPTIONS)
construct a line, which will probably not have the same begin and end point. The
POINTS are passed as new(points), and the other OPTIONS are passed to new() as well.
$obj->new([OPTIONS], [POINTS], [OPTIONS])
Geo::Line->new([OPTIONS], [POINTS], [OPTIONS])
When called as instance method, the projection, ring, and filled attributes are taken
from the initiator, like a clone with modification.
-Option --Defined in --Default
bbox Math::Polygon undef
clockwise Math::Polygon undef
filled <false>
points <data>
proj Geo::Shape see Geo::Proj::defaultProjection()
ring <false>
bbox => ARRAY
clockwise => BOOLEAN
filled => BOOLEAN
Implies ring. The filled of the ring is included in the geometrical shape.
points => ARRAY-OF-POINTS|ARRAY-OF-COORDINATES
With this option, you can specify either Geo::Point objects, or coordinate pairs
which will get transformed into such objects. WARNING: in that case, the
coordinates must be in xy order.
proj => LABEL
ring => BOOLEAN
The first point is the last point. When specified, you have to make sure that this
is the case. If ring() is used to create this object, that routine will
check/repair it for you.
example:
my $point = Geo::Point->xy(1, 2);
my $line = Geo::Line->new
( points => [$point, [3,4], [5,6], $point]
, ring => 1
)'
$obj->ring(POINTS, OPTIONS)
Geo::Line->ring(POINTS, OPTIONS)
The first and last point will be made the same: if not yet, than a reference to the
first point is appended to the list. A "ring" does not cover the internal.
Geo::Line->ringFromString(STRING, [PROJECTION])
Calls bboxFromString() and then produces a ring object from than. Don't forget the
"eval" when you call this method.
Attributes
$obj->geopoint(INDEX, [INDEX, ..])
Returns the Geo::Point for the point with the specified INDEX or indices.
$obj->geopoints()
In LIST context, this returns all points as separate scalars: each is a Geo::Point
with projection information. In SCALAR context, a reference to the coordinates is
returned.
With points(), you get arrays with XY coordinates returned, but without the projection
information. That will be much faster, but not sufficient for some uses.
$obj->isFilled()
Returns a true value is the internals of the ring of points are declared to belong to
the shape.
$obj->isRing()
Returns a true value if the sequence of points are a ring or filled: the first point
is the last.
$obj->nrPoints()
See "Attributes" in Math::Polygon
$obj->order()
See "Attributes" in Math::Polygon
$obj->point(INDEX, [INDEX, ...])
See "Attributes" in Math::Polygon
$obj->points()
See "Attributes" in Math::Polygon
$obj->proj()
See "Attributes" in Geo::Shape
$obj->proj4()
See "Attributes" in Geo::Shape
Projections
$obj->in(LABEL|'utm')
See "Projections" in Geo::Shape
$obj->projectOn(NICK, POINTS)
See "Projections" in Geo::Shape
Geometry
$obj->area()
Returns the area enclosed by the polygon. Only useful when the points are in some
orthogonal projection.
$obj->bbox()
The bounding box coordinates. These are more useful for rings than for open line
pieces.
$obj->bboxCenter()
See "Geometry" in Geo::Shape
$obj->bboxRing([XMIN, YMIN, XMAX, YMAX, [PROJ]])
Geo::Line->bboxRing([XMIN, YMIN, XMAX, YMAX, [PROJ]])
See "Geometry" in Geo::Shape
$obj->beautify(OPTIONS)
See "Geometry" in Math::Polygon
$obj->centroid()
See "Geometry" in Math::Polygon
$obj->clip((XMIN,XMAX,YMIN,YMAX)|OBJECT)
Clip the shape to the bounding box of OBJECT, or the boxing parameters specified. A
list of Geo::Line objects is returned if anything is inside the object.
On the moment Math::Polygon::lineClip() and Math::Polygon::fillClip1() are used to do
the job. In the future, that may change.
$obj->clockwise()
See "Geometry" in Math::Polygon
$obj->contains(POINT)
See "Geometry" in Math::Polygon
$obj->counterClockwise()
See "Geometry" in Math::Polygon
$obj->distance(OBJECT, [UNIT])
See "Geometry" in Geo::Shape
$obj->equal((OTHER|ARRAY, [TOLERANCE])|POINTS)
See "Geometry" in Math::Polygon
$obj->isClockwise()
See "Geometry" in Math::Polygon
$obj->isClosed()
See "Geometry" in Math::Polygon
$obj->length()
The length of the line, only useful in a orthogonal coordinate system (projection).
See also perimeter().
$obj->perimeter()
The length of the line on the ring. A check is performed that the ring is closed, but
further this returns the result of length()
$obj->same((OTHER|ARRAY, [TOLERANCE])|POINTS)
See "Geometry" in Math::Polygon
$obj->startMinXY()
See "Geometry" in Math::Polygon
Transformations
$obj->grid(OPTIONS)
See "Transformations" in Math::Polygon
$obj->mirror(OPTIONS)
See "Transformations" in Math::Polygon
$obj->move(OPTIONS)
See "Transformations" in Math::Polygon
$obj->resize(OPTIONS)
See "Transformations" in Math::Polygon
$obj->rotate(OPTIONS)
See "Transformations" in Math::Polygon
$obj->simplify(OPTIONS)
See "Transformations" in Math::Polygon
Clipping
$obj->fillClip1(BOX)
See "Clipping" in Math::Polygon
$obj->lineClip(BOX)
See "Clipping" in Math::Polygon
Display
$obj->deg2dm(DEGREES, POS, NEG)
Geo::Line->deg2dm(DEGREES, POS, NEG)
See "Display" in Geo::Shape
$obj->deg2dms(DEGREES, POS, NEG)
Geo::Line->deg2dms(DEGREES, POS, NEG)
See "Display" in Geo::Shape
$obj->dms2deg(DMS)
Geo::Line->dms2deg(DMS)
See "Display" in Geo::Shape
$obj->string([PROJECTION])
Returns a string representation of the line, which is also used for stringification.
example:
OVERLOAD
overload: '""' (stringification)()
See "OVERLOAD" in Geo::Shape
overload: 'bool' (truth value)()
See "OVERLOAD" in Geo::Shape
DIAGNOSTICS
Error: area requires a ring of points
If you think you have a ring of points (a polygon), than do specify that when that
object is instantiated (ring() or new(ring)).
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: in() not implemented for a $class
Error: perimeter requires a ring of points
SEE ALSO
This module is part of Geo-Point distribution version 0.94, built on December 21, 2012.
Website: http://perl.overmeer.net/geo/ All modules in this suite: "Geo::Point",
"Geo::Proj4", "Geo::WKT", "Math::Polygon", "Geo::GML", "Geo::ISO19139", "Geo::EOP",
"Geo::Format::Envisat", and "Geo::Format::Landsat".
Please post questions or ideas to the mailinglist at http://geo-perl@list.hut.fi
LICENSE
Copyrights 2005-2012 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://www.perl.com/perl/misc/Artistic.html