MultiPolygon

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Next version — This documentation describes a major version that is not yet the current stable release of spatial-types.

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What is a MultiPolygon?

A MultiPolygon groups Polygon objects into one spatial value. Each member has its own exterior ring and may have holes.

MultiPolygon — Supported representations

Availability in the current version of Spatial Types:

Coordinate layout	Geometry Mutable	Geometry Immutable	Geography Mutable	Geography Immutable
XY	✅	✅	✅	✅
XYZ	✅	✅	✅	✅
XYM	✅	✅	✅	✅
XYZM	✅	✅	✅	✅

Creating the illustrated objects

The examples recreate the labelled objects above using Geometry in XY. Composer’s autoloader must already be loaded. Variable names match the point letters in the illustration.

Immutable objects

<?php

use LongitudeOne\SpatialTypes\Types\Dimension2\Geometry\PointImmutable;
use LongitudeOne\SpatialTypes\Types\Dimension2\Geometry\LineStringImmutable;
use LongitudeOne\SpatialTypes\Types\Dimension2\Geometry\PolygonImmutable;
use LongitudeOne\SpatialTypes\Types\Dimension2\Geometry\MultiPolygonImmutable;

// Immutable objects must be fully initialized through their constructors.

$a = new PointImmutable(6.5, 7);
$b = new PointImmutable(28.5, 7.5);
$c = new PointImmutable(25, 20);
$d = new PointImmutable(10.5, 18.5);
$e = new PointImmutable(43, 20);
$f = new PointImmutable(68.5, 20);
$g = new PointImmutable(68.5, 6.5);
$h = new PointImmutable(43, 6.5);
$i = new PointImmutable(50.5, 15.5);
$j = new PointImmutable(61, 15.5);
$k = new PointImmutable(61, 10.5);
$l = new PointImmutable(50.5, 10.5);

$firstRing = new LineStringImmutable([$a, $b, $c, $d, $a]);
$firstPolygon = new PolygonImmutable([$firstRing]);
$exteriorRing = new LineStringImmutable([$e, $f, $g, $h, $e]);
$interiorRing = new LineStringImmutable([$i, $j, $k, $l, $i]);
$polygonWithHole = new PolygonImmutable([$exteriorRing, $interiorRing]);
$multiPolygon = new MultiPolygonImmutable([$firstPolygon, $polygonWithHole]);

Mutable objects

<?php

use LongitudeOne\SpatialTypes\Types\Dimension2\Point;
use LongitudeOne\SpatialTypes\Types\Dimension2\LineString;
use LongitudeOne\SpatialTypes\Types\Dimension2\Polygon;
use LongitudeOne\SpatialTypes\Types\Dimension2\MultiPolygon;

$a = new Point(6.5, 7);
$b = new Point(28.5, 7.5);
$c = new Point(25, 20);
$d = new Point(10.5, 18.5);
$e = new Point(43, 20);
$f = new Point(68.5, 20);
$g = new Point(68.5, 6.5);
$h = new Point(43, 6.5);
$i = new Point(50.5, 15.5);
$j = new Point(61, 15.5);
$k = new Point(61, 10.5);
$l = new Point(50.5, 10.5);

$firstRing = new LineString([$a, $b, $c, $d, $a]);
$firstPolygon = new Polygon([$firstRing]);
$exteriorRing = new LineString([$e, $f, $g, $h, $e]);
$interiorRing = new LineString([$i, $j, $k, $l, $i]);
$polygonWithHole = new Polygon([$exteriorRing, $interiorRing]);
// Using the constructor.
$multiPolygon = new MultiPolygon([$firstPolygon, $polygonWithHole]);

// Alternatively, adding members with methods.
$multiPolygon = new MultiPolygon()
    ->addElement($firstPolygon)
    ->addElement($polygonWithHole);