CompoundCurve

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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 CompoundCurve?

A CompoundCurve is an ordered sequence of curve components joined at their endpoints. In Spatial Types, its direct components are LineString or CircularString objects.

Endpoint continuity describes a valid compound curve; construction does not enforce it. Disconnected or empty components can remain stored. Use explicit geometric validation to check continuity.

CompoundCurve — 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\CircularStringImmutable;
use LongitudeOne\SpatialTypes\Types\Dimension2\Geometry\CompoundCurveImmutable;

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

$a = new PointImmutable(7.5, 8);
$b = new PointImmutable(28.5, 8);
$c = new PointImmutable(40.5, 20);
$d = new PointImmutable(52.5, 8);

$line = new LineStringImmutable([$a, $b]);
$arc = new CircularStringImmutable([$b, $c, $d]);
$curve = new CompoundCurveImmutable([$line, $arc]);

Mutable objects

<?php

use LongitudeOne\SpatialTypes\Types\Dimension2\Point;
use LongitudeOne\SpatialTypes\Types\Dimension2\LineString;
use LongitudeOne\SpatialTypes\Types\Dimension2\CircularString;
use LongitudeOne\SpatialTypes\Types\Dimension2\CompoundCurve;

$a = new Point(7.5, 8);
$b = new Point(28.5, 8);
$c = new Point(40.5, 20);
$d = new Point(52.5, 8);

$line = new LineString([$a, $b]);
$arc = new CircularString([$b, $c, $d]);
// Using the constructor.
$curve = new CompoundCurve([$line, $arc]);

// Alternatively, adding components with methods.
$curve = new CompoundCurve()
    ->addCurve($line)
    ->addCurve($arc);