PHP-class for proj4 This is a PHP-Class for geographic coordinates transformation using proj4 definitions, thanks to a translation from Proj4JS.
To keep up with the relentless pace of PHP versions and best practice, the following features are being implemented on this package:
- Namespacing.
- PHP5.4+ syntax (not aiming to be bleeding edge here, just yet)
- PSR-2 styling
- PSR-4 autoloader
- semver release numbers to packagist.org
- Full compatibility with composer
- Tests to come once the above is implemented.
Legacy branches proj4php5.2 and proj4php7.1 will be maintained for older applications that need it.
// Use a PSR-4 autoloader for the `proj4php` root namespace.
include("vendor/autoload.php");
use proj4php\Proj4php;
use proj4php\Proj;
use proj4php\Point;
// Initialise Proj4
$proj4 = new Proj4php();
// Create two different projections.
$projL93 = new Proj('EPSG:2154', $proj4);
$projWGS84 = new Proj('EPSG:4326', $proj4);
// Create a point.
$pointSrc = new Point(652709.401, 6859290.946, $projL93);
echo "Source: " . $pointSrc->toShortString() . " in L93 <br>";
// Transform the point between datums.
$pointDest = $proj4->transform($projWGS84, $pointSrc);
echo "Conversion: " . $pointDest->toShortString() . " in WGS84<br><br>";
// Source: 652709.401 6859290.946 in L93
// Conversion: 2.3557811127971 48.831938054369 in WGS84
There are also ways to define inline projections. Check http://spatialreference.org/ref/epsg/ and seek for your projection and proj4 or OGC WKT definitions.
Add a new projection from proj4 definition with a name :
// add it to proj4
$proj4->addDef("EPSG:27700",'+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +datum=OSGB36 +units=m +no_defs');
// then Create your projections
$projOSGB36 = new Proj('EPSG:27700',$proj4);
Or without a name :
// Create your projection
$projOSGB36 = new Proj('+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy +datum=OSGB36 +units=m +no_defs',$proj4);
You can also create your projection from OGC WKT definition :
$projOSGB36 = new Proj('PROJCS["OSGB 1936 / British National Grid",GEOGCS["OSGB 1936",DATUM["OSGB_1936",SPHEROID["Airy 1830",6377563.396,299.3249646,AUTHORITY["EPSG","7001"]],AUTHORITY["EPSG","6277"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4277"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",49],PARAMETER["central_meridian",-2],PARAMETER["scale_factor",0.9996012717],PARAMETER["false_easting",400000],PARAMETER["false_northing",-100000],AUTHORITY["EPSG","27700"],AXIS["Easting",EAST],AXIS["Northing",NORTH]]',$proj4);
Feel free to fork us and submit your changes!
Proj4php is also an OSGeo community project. See here for further details.