README

Parser library for 2D, 3D, and 4D Open Geospatial Consortium (OGC) WKB or PostGIS EWKB spatial object data.

Note

This package is the continuation of the now abandoned creof/wkt-parser package.

Installation

composer require longitude-one/wkb-parser

Usage

There are two use patterns for the parser. The value to be parsed can be passed into the constructor, then parse() called on the returned Parser object:

$parser = new Parser($input);

$value = $parser->parse();

If many values need to be parsed, a single Parser instance can be used:

$parser = new Parser();

$value1 = $parser->parse($input1);
$value2 = $parser->parse($input2);

Input value

Encoding

The parser currently supports 3 WKB encodings:

• OGC v1.1
• OGC v1.2
• PostGIS EWKB

Format

The parser supports a number of input formats:

• Binary string (as returned from database or pack('H*', $hexString))
• Bare hexadecimal text string ('01010000003D0AD7A3.....')
• Hexadecimal test string prepended with x, X, 0x, or 0X ('0x01010000003D0AD7A3.....', etc.)

Return

The parser will return an array with the keys type, value, srid, and dimension.

• type string, the uppercase spatial object type (POINT, LINESTRING, etc.) without any dimension.
• value array, contains integer or float values for points, nested arrays containing these based on spatial object type, or empty array for EMPTY geometry.
• srid integer, the SRID if present in EWKB value, null otherwise.
• dimension string, will contain Z, M, or ZM for the respective 3D and 4D objects, null otherwise.

Exceptions

The Reader and Parser will throw exceptions implementing interface CrEOF\Geo\WKB\Exception\ExceptionInterface.

References

• PostGIS EWKB - https://github.com/postgis/postgis/blob/master/doc/ZMSgeoms.txt
• OGC Simple Feature Access, Part 1 - http://www.opengeospatial.org/standards/sfa
• OGC Simple Feature Access, Part 2 - http://www.opengeospatial.org/standards/sfs