NAME
Geo::Surface - A surface description.
INHERITANCE
Geo::Surface
is a Geo::Shape
SYNOPSIS
my $island1 = Geo::Line->filled(...);
my $island2 = Geo::Surface->new(...);
my $islands = Geo::Surface->new($island1, $island2)
DESCRIPTION
In this context, a "surface" is defined as a set of filled areas with possible enclosures in one projection system. One set of islands can be kept as one surface, or the shapefile data of a country.
METHODS
Constructors
Geo::Surface->new([COMPONENTS], [OPTIONS])
When called as instance method, some defaults are copied from the object where the call is made upon.
COMPONENTS are Math::Polygon, Math::Polygon::Surface, Geo::Line, Geo::Surface objects. When an ARRAY is specfied as COMPONENT, it will be used to instantiate a Math::Polygon::Surface object. In case of a Geo::Surface, the included polygons are translated to the specified projection.
Option--Defined in--Default
proj Geo::Shape <see Geo::Proj::defaultProjection()
. proj => LABEL
Attributes
$obj->component(INDEX, [INDEX, ...])
Returns the component (or components) with the specified INDEX(es). One Math::Polygon::Surface in scalar context, and multiple in list context.
$obj->components
Returns a list of Math::Polygon::Surface objects, together forming the surface.
$obj->nrComponents
Returns the number of components.
$obj->proj
Projections
$obj->in(LABEL|'utm')
$obj->projectOn(NICK, POINTS)
Geometry
$obj->area
Returns the area enclosed by the combined components. Only useful when the points are in some orthogonal projection.
$obj->bbox
The bounding box of the combined polygons.
$obj->bboxCenter
$obj->bboxRing([XMIN, YMIN, XMAX, YMAX, [PROJ]])
Geo::Surface->bboxRing([XMIN, YMIN, XMAX, YMAX, [PROJ]])
$obj->distance(OBJECT, [UNIT])
$obj->equal(OTHER, [TOLERANCE])
Detailed calculation whether two surfaces are equal is a lot of work. Therefore, only exactly equal surface descriptions are considered equivalent.
$obj->perimeter
The length of the outer polygons of all components. Only useful in a orthogonal coordinate systems.
$obj->sameAs(OTHER, TOLERANCE)
Display
$obj->deg2dm(DEGREES, POS, NEG)
Geo::Surface->deg2dm(DEGREES, POS, NEG)
$obj->deg2dms(DEGREES, POS, NEG)
Geo::Surface->deg2dms(DEGREES, POS, NEG)
$obj->dms2deg(DMS)
Geo::Surface->dms2deg(DMS)
$obj->toString([PROJECTION])
Returns a string representation of the line, which is also used for stringification.
DIAGNOSTICS
Warning: Geo::Line is should be filled
When Geo::Line objects are used to compose a surface, each of them must be filled. Representation of rivers and such do not belong in a surface description.
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: not known what to do with $component
SEE ALSO
This module is part of Geo-Point distribution version 0.08, built on March 31, 2008. Website: http://perl.overmeer.net/geo/
LICENSE
Copyrights 2005-2008 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