itamair/geophp

GeoPHP is a open-source native PHP library for doing geometry operations. It is written entirely in PHP and can therefore run on shared hosts. It can read and write a wide variety of formats: WKT (including EWKT), WKB (including EWKB), GeoJSON, KML, GPX, GeoRSS). It works with all Simple-Feature geometries (Point, LineString, Polygon, GeometryCollection etc.) and can be used to get centroids, bounding-boxes, area, and a wide variety of other useful information.