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Table of Contents
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geoPHP provides a static class that contains useful utility functions. All methods must be called statically.
$geometry = geoPHP::load('MULTILINESTRING((10 10,20 20,10 40))','wkt');
$reduced_geometry = geoPHP::geometryReduce($geometry);
| Method | Description | Returns |
| version | Provides the current geoPHP version. Useful if you need to check compatablity | Numeric String |
| load | Load from an adapter format (like wkt) into a geometry. The first argument is the data, the second one is the format of the data ('wkt','wkb','json','kml','gpx','google_geocode'). All additional arguments are passed along to the read method of the relevant adapte | Geometry |
| getAdapterMap | Get a list of adapters as an array keyed by the value that should be passed to geoPHP::load | Array |
| geometryList | List all geometry types | Array |
| geosToGeometry | Given a GEOSGeometry, get a geoPHP geometry | Geometry |
| geometryReduce | Reduce a geometry, or an array of geometries, into their \'lowest\' available common geometry. For example a GeometryCollection of only points will become a MultiPoint, while a multi-point containing a single point will return a point. An array of geometries can be passed and they will be compiled into a single geometry. | Geometry |
| geosInstalled | Check if the GEOS php extension is installed and working | Boolean |
Adapters are responsible for getting data in and out of geoPHP Geometries. Generally you will use an adapter to load data into a geoPHP geometry, do various manipulations on the geometry, then use another adapter to write it out to another (or the same) format. You can also use adapters by themselves to simply do conversion from one format to another (See example-format-converter for an example of this). Adapters should be instantiated and not called statically.
$wkb_reader = new WKB();
$geometry = $wkb_reader->read('0101000000000000000000f03f000000000000f03f',TRUE);
$wkt_writer = new wkt();
$wkt = $wkt_writer->write($geometry);
| Method | Description | Returns |
| read | Read in input (generally a string) and return a Geometry | Geometry |
| write | Write out the given geometry into the adapter formater | String |
Geometries form the heart of the geoPHP library. Once you have loaded your data into a Geometry object, you have access to all the various methods detailed below for doing conversions, transformations, and operations. While generally you would use an adapter to get a Geometry object, they can also be built by hand. See the constructor methods in the classes to see how to do this. GEOS-php extension needs to be installed in order to use some of the advanced methods (detailed below).
$poly1 = $geoPHP::load('POLYGON((30 10,10 20,20 40,40 40,30 10))','wkt');
$poly2 = $geoPHP::load('POLYGON((35 10,10 20,15 40,45 45,35 10),(20 30, 35 35, 30 20, 20 30))','wkt');
$combined_poly = $poly1->union($poly2);
$kml = $combined_poly->out('kml');
Common Methods
| Method | Description | Returns |
| out | Outputs the geometry into the specified adapter format. Available formats are wkt, wkb, json, kml, gpx, google_geocode | String |
| area | The area of this Polygon (or GeometryCollection), as measured in the spatial reference system of the geometry | Float |
| boundary | Returns the closure of the combinatorial boundary of this geometric object. | LinearRing |
| envelope | The minimum bounding box for this Geometry, returned as a Geometry. | Polygon |
| getBBox | The minimum bounding box for this Geometry, returned as an array. Also see envelope() | Array |
| centroid | The mathematical centroid for this geometry as a Point. For polygons, the result is not guaranteed to be interior. | Point |
| length | The length of this Curve in its associated spatial reference. | Float |
| y | The y-coordinate value for this Point. | Float |
| x | The x-coordinate value for this Point. | Float |
| numGeometries | The number of component geometries in this collection | Integer |
| geometryN | Returns the geometry N in this collection. Note that the index starts at 1. | Geometry |
| startPoint | The start Point of this LineString | Point |
| endPoint | The end Point of this LineString | Point |
| isRing | Returns 1 (TRUE) if this Curve is closed() and this Curve isSimple(). | Boolean |
| isClosed | Returns 1 (TRUE) if this Curve is closed. StartPoint() == EndPoint(). | Boolean |
| getComponents | Get all sub-geometry components of the geometry | Array of geometries |
| numPoints | The number of Points in this LineString | Integer |
| pointN | Returns the specified Point N in this LineString. Note that the index starts at 1. | Point |
| exteriorRing | Returns the exterior ring of this Polygon. | LineString |
| numInteriorRings | Returns the number of interior rings in this Polygon. | Integer |
| interiorRingN | Returns the Nth interior ring for this Polygon as a LineString. Note that the index starts at 1. | LineString |
| dimension | The inherent dimension of this geometric object. In non-homogeneous collections, this will return the largest topological dimension of the contained objects. | Integer |
| geometryType | Returns the name of the instantiable subtype of Geometry of which this geometric object is an instantiable member. The name of the subtype of Geometry is returned as a string. | String |
| SRID | Returns the Spatial Reference System ID for this geometric object. | integer |
| setSRID | Set the Spatial Reference System ID for this geometric object. | NULL |
| asArray | Get the given geometry as an array of components (recursive) | Array |
| getGeoInterface | Get the geometryType and Coordinates as an array | Array |
Aliases
| Method | Description | Returns |
| getCentroid | Alias for centroid() | Point |
| getArea | Alias for area() | Float |
| getX | Alias for x() | Float |
| getY | Alias for y() | Float |
| getGeos | Alias for geos() | GEOSGeometry |
| getGeomType | Alias for geometryType() | String |
| getSRID | Alias for SRID() | Integer |
| asText | Alias for $this->out('wkt') | String |
| asBinary | Alias for $this->out('wkb') | String |
Advanced Methods
The GEOS-php extension needs to be installed for these functions to be available
| Method | Description | Returns |
| geos | Return a GEOSGeometry object representing this geometry | GEOSGeometry |
| setGeos | Set a GEOSGeometry object representing this geometry | NULL |
| pointOnSurface | A Point guaranteed to be within a polygon | Point |
| equals | Returns 1 (TRUE) if this geometry is “spatially equal” to another Geometry | Boolean |
| equalsExact | Returns 1 (TRUE) if this gemometric object is exactly the same as another object, including the ordering of component parts | Boolean |
| relate | Returns 1 (TRUE) if this geometric object is spatially related to anotherGeometry by testing for intersections between the interior, boundary and exterior of the two geometric objects as specified by the values in the intersectionPatternMatrix. This returns FALSE if all the tested intersections are empty except exterior (this) intersect exterior (another). | Boolean |
| checkValidity | Boolean | |
| isSimple | Returns 1 (TRUE) if this geometry does not pass through the same point in space more than once | Boolean |
| project | Project the geometry from from one SRID to another | Geometry |
| buffer | Returns a geometric object that represents all Points whose distance from this geometric object is less than or equal to distance. Calculations are in the spatial reference system of this geometric object. Because of the limitations of linear interpolation, there will often be some relatively small error in this distance, but it should be near the resolution of the coordinates used. | Geometry |
| intersection | Returns a geometric object that represents the Point set intersection of this geometric object with anotherGeometry. See http://en.wikipedia.org/wiki/Intersection_(set_theory) | Geometry |
| convexHull | Returns a geometric object that represents the convex hull of this geometric object. See http://en.wikipedia.org/wiki/Convex_hull | Geometry |
| difference | Returns a geometric object that represents the Point set difference of this geometric object with anotherGeometry. | Geometry |
| symDifference | Returns a geometric object that represents the Point set symmetric difference of this geometric object with another Geometry. See http://en.wikipedia.org/wiki/Symmetric_difference | Geometry |
| union | Returns a geometric object that represents the Point set union of this geometric object with anotherGeometry. See http://en.wikipedia.org/wiki/Union_(set_theory) | Geometry |
| simplify | Simplify the geometry | Geometry |
| disjoint | Returns 1 (TRUE) if this geometric object is “spatially disjoint” from another Geometry. | Boolean |
| touches | Returns 1 (TRUE) if this geometric object “spatially touches” another Geometry. | Boolean |
| intersects | Returns 1 (TRUE) if this geometric object “spatially intersects” another Geometry. | Boolean |
| crosses | Returns 1 (TRUE) if this geometric object “spatially crosses? another Geometry. | Boolean |
| within | Returns 1 (TRUE) if this geometric object is “spatially within” another Geometry. | Boolean |
| contains | Returns 1 (TRUE) if this geometric object “spatially contains” another Geometry. | Boolean |
| overlaps | Returns 1 (TRUE) if this geometric object “spatially overlaps” another Geometry. | Boolean |
| covers | Alias for contains() | Boolean |
| coveredBy | Alias for within() | Boolean |
| distance | Returns the shortest distance between any two Points in the two geometric objects as calculated in the spatial reference system of this geometric object. Because the geometries are closed, it is possible to find a point on each geometric object involved, such that the distance between these 2 points is the returned distance between their geometric objects. | Float |
| hausdorffDistance | See http://en.wikipedia.org/wiki/Hausdorff_distance | Float |
Placeholders
These methods are part of the specification, but are not really supported by geoPHP.
| Method | Description | Returns |
| hasZ | returns FALSE. geoPHP does not support Z values at the moment. | Boolean |
| is3D | returns FALSE. geoPHP does not support 3D geometries at the moment. | Boolean |
| isMeasured | returns FALSE. geoPHP does not yet support M values | Boolean |
| isEmpty | returns FALSE. geoPHP does not yet support empty geometries | Boolean |
| coordinateDimension | returns 2. geoPHP only supports 2-dimentional space | Integer |
| z | returns NULL. geoPHP does not support Z values at the moment | NULL |
| m | returns NULL. geoPHP does not support M values | NULL |