PHPWKTParser

Well-known text (WKT) is a text markup language for representing vector geometry objects on a map, spatial reference systems of spatial objects and transformations between spatial reference systems.

EWKT (Extended Well-Known Text), a PostGIS-specific format that includes the spatial reference system identifier (SRID) and up to 4 ordinate values (XYZM), is also supported (ex: SRID=31370;POINT(44 60)).

PHPWKTParser provides a simple usage helper class to read WKT and EWKT and parse this text representation to a workable PHP array holding the parsed WKT/EWKT definition. Read and parse 2D, 3D and 4D WKT (Well Known Text) / EWKT (Extended Well-Known Text) object strings into geometry objects with this simple WKT PHP adapter library.

Installation

Install the package through composer:

composer require daandesmedt/phpwktadapter

Make sure, that you include the composer autoloader somewhere in your codebase.

Supported geometry

Geometry Type	Example
POINT	POINT(30 10)
LNESTRING	LINESTRING(30 10, 10 30, 40 40)
POLYGON	POLYGON((0 0,10 0,10 10,0 10,0 0))
MULTIPOINT	MULTIPOINTZM(0 0 10 10,10 0 0 0,10 10 0 0,20 20 0 10)
MULTILINESTRING	MULTILINESTRING((0 0,10 0,10 10,0 10))
MULTIPOLYGON	MULTIPOLYGON(((40 40, 20 45, 45 30, 40 40)), ((20 35, 10 30, 10 10, 30 5, 45 20, 20 35), (30 20, 20 15, 20 25, 30 20)))
GEOMETRYCOLLECTION	GEOMETRYCOLLECTION(POINT(10 20),LINESTRING(0 0,10 0))

PHPWKTParser parsed and returned geometry array response

The read($wkt) function of the PHPWKTParser adapter will return a associative array as representation of the parsed WKT/EWKT (in case of valid).

array(
    // the geometry object type
    "type"      =>  string,
    // integer or float values for POINT - nested array (integer or float) for other geometry types
    "value"     =>  array,
    // integer representing the EWKT SRID, null when not present 
    "srid"      =>  integer | null,
    // string (Z, M or ZM) representing the dimension, null when not present 
    "dimension" =>  string | null
)

Working examples

Working examples can be found in the examples folder.

Sample usage

<?php 

require __DIR__ . '/../vendor/autoload.php';

use daandesmedt\PHPWKTAdapter\WKTAdapter;

$adapter = new WKTAdapter();
$res = $adapter->read('SRID=31370;POINT(30 10)');
var_dump($res); 

Handling exceptions

Invalid format in the specified WKT / EWKT will result in a UnexpectedValueException thrown by the WKTAdapter .

<?php 

require __DIR__ . '/../vendor/autoload.php';

use daandesmedt\PHPWKTAdapter\WKTAdapter;

$adapter = new WKTAdapter();

try {
    $res = $adapter->read('SRID=31370;POINT(bad format)');
} catch (UnexpectedValueException $e) {
    var_dump($e->getMessage());
}