---
name: "Geo::Surface"
section: "3pm"
platform: "linux"
package: "libgeo-point-perl"
version: "0.98-1"
release: "Debian 10 (Buster)"
platforms: ["linux"]
url: "https://new.carta.tech/Geo::Surface"
---

# Geo::Surface(3pm)

A surface description.

## NAME

Geo::Surface - A surface description.

## INHERITANCE

```
 Geo::Surface
   is a Geo::Shape
```

## SYNOPSIS

```
 my $island = Geo::Surface->new($outer, $lake1, $lake2);
```

## DESCRIPTION

In this context, a "surface" is defined as a single filled area with possible enclosures in one projection system.

Extends "DESCRIPTION" in Geo::Shape.

## METHODS

Extends "METHODS" in Geo::Shape.

### Constructors

Extends "Constructors" in Geo::Shape.

- $obj-\>**new**( \<$surface \| \<$outer,$inner,...\> \>, %options )

  - Geo::Surface-\>**new**( \<$surface \| \<$outer,$inner,...\> \>, %options )

  When called as instance method, some defaults are copied from the object where the call is made upon.

  You may either provide a Math::Polygon::Surface `$surface`, or a LIST of lines.  In the latter case, the first line is the `$outer` polygon of the surface, and the other are all `$inner` enclosures: lakes.  Lines are and Geo::Line, Math::Polygon objects, or ARRAY of points.

  If no projection is specified, then the projection of the first Geo-encoded line will be used.

  ```
   -Option--Defined in--Default
    proj    Geo::Shape  see Geo::Proj::defaultProjection()
  ```

  - proj =\> LABEL

    ### Attributes

Extends "Attributes" in Geo::Shape.

- $obj-\>**geoInner**()

  Returns a LIST of enclosed polygons, converted to Geo::Line objects.

- $obj-\>**geoOuter**()

  Returns the outer polygon as Geo::Line object.

- $obj-\>**inner**()

  Returns a LIST of enclosed Math::Polygon objects.

- $obj-\>**outer**()

  Returns the outer Math::Polygon.

- $obj-\>**proj**()

  Inherited, see "Attributes" in Geo::Shape

- $obj-\>**proj4**()

  Inherited, see "Attributes" in Geo::Shape

### Projections

Extends "Projections" in Geo::Shape.

- $obj-\>**in**( \<$label\|'utm'\> )

  Inherited, see "Projections" in Geo::Shape

- $obj-\>**projectOn**($nick, @points)

  Inherited, see "Projections" in Geo::Shape

### Geometry

Extends "Geometry" in Geo::Shape.

- $obj-\>**area**()

  Returns the area enclosed by the outer polygon, minus the erea of the enclosures.  Only useful when the points are in some orthogonal projection.

- $obj-\>**bbox**()

  The bounding box of outer surface polygon.

- $obj-\>**bboxCenter**()

  Inherited, see "Geometry" in Geo::Shape

- $obj-\>**bboxRing**( \[$xmin, $ymin, $xmax, $ymax, \[$proj\]\] )

  - Geo::Surface-\>**bboxRing**( \[$xmin, $ymin, $xmax, $ymax, \[$proj\]\] )

  Inherited, see "Geometry" in Geo::Shape

- $obj-\>**distance**( $object, \[$unit\] )

  Inherited, see "Geometry" in Geo::Shape

- $obj-\>**perimeter**()

  The length of the outer polygon. Only useful in a orthogonal coordinate systems.

### Display

Extends "Display" in Geo::Shape.

- $obj-\>**deg2dm**($degrees, $pos, $neg)

  - Geo::Surface-\>**deg2dm**($degrees, $pos, $neg)

  Inherited, see "Display" in Geo::Shape

- $obj-\>**deg2dms**($degrees, $pos, $neg)

  - Geo::Surface-\>**deg2dms**($degrees, $pos, $neg)

  Inherited, see "Display" in Geo::Shape

- $obj-\>**dms2deg**($dms)

  - Geo::Surface-\>**dms2deg**($dms)

  Inherited, see "Display" in Geo::Shape

- $obj-\>**toString**( \[$projection\] )

  Returns a string representation of the line, which is also used for stringification.

## 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

- 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 0.98, 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/*