Geokit is a PHP toolkit to solve geo-related tasks like:
Install the latest version with Composer.
composer require geokit/geokit
Check the Packagist page for all available versions.
A Distance instance allows for a convenient representation of a distance unit of measure.
use Geokit\Distance;
$distance = new Distance(1000); // Defaults to meters
// or
$distance = new Distance(1, Distance::UNIT_KILOMETERS);
$meters = $distance->meters();
$kilometers = $distance->kilometers();
$miles = $distance->miles();
$yards = $distance->yards();
$feet = $distance->feet();
$inches = $distance->inches();
$nauticalMiles = $distance->nautical();
A Distance can also be created from a string with an optional unit.
use Geokit\Distance;
$distance = Distance::fromString('1000'); // Defaults to meters
$distance = Distance::fromString('1000m');
$distance = Distance::fromString('1km');
$distance = Distance::fromString('100 miles');
$distance = Distance::fromString('100 yards');
$distance = Distance::fromString('1 foot');
$distance = Distance::fromString('1 inch');
$distance = Distance::fromString('234nm');
A Position
is a fundamental construct representing a geographical position in
x
(or longitude
) and y
(or latitude
) coordinates.
Note, that x
/y
coordinates are kept as is, while longitude
/latitude
are
normalized.
use Geokit\Position;
$position = Position::fromXY(181, 91);
$x = $position->x(); // Returns -179.0, normalized
$y = $position->y(); // Returns 89.0, normalized
A BoundingBox instance represents a rectangle in geographical coordinates, including one that crosses the 180 degrees longitudinal meridian.
It is constructed from its left-bottom (south-west) and right-top (north-east) corner points.
use Geokit\BoundingBox;
use Geokit\Position;
$southWest = Position::fromXY(2, 1);
$northEast = Position::fromXY(2, 1);
$boundingBox = BoundingBox::fromCornerPositions($southWest, $northEast);
$southWestPosition = $boundingBox->southWest();
$northEastPosition = $boundingBox->northEast();
$center = $boundingBox->center();
$span = $boundingBox->span();
$boolean = $boundingBox->contains($position);
$newBoundingBox = $boundingBox->extend($position);
$newBoundingBox = $boundingBox->union($otherBoundingBox);
With the expand()
and shrink()
methods, you can expand or shrink a
BoundingBox instance by a distance.
use Geokit\Distance;
$expandedBoundingBox = $boundingBox->expand(
Distance::fromString('10km')
);
$shrinkedBoundingBox = $boundingBox->shrink(
Distance::fromString('10km')
);
The toPolygon()
method converts the BoundingBox to an equivalent Polygon
instance.
$polygon = $boundingBox->toPolygon();
A Polygon instance represents a two-dimensional shape of connected line segments and may either be closed (the first and last point are the same) or open.
use Geokit\BoundingBox;
use Geokit\Polygon;
use Geokit\Position;
$polygon = Polygon::fromPositions(
Position::fromXY(0, 0),
Position::fromXY(1, 0),
Position::fromXY(1, 1)
);
$closedPolygon = $polygon->close();
/** @var Position $position */
foreach ($polygon as $position) {
}
$polygon->contains(Position::fromXY(0.5, 0.5)); // true
/** @var BoundingBox $boundingBox */
$boundingBox = $polygon->toBoundingBox();
Geokit provides several functions to perform geographic calculations.
distanceHaversine(Position $from, Position $to)
:
Calculates the approximate sea level great circle (Earth) distance between two
points using the Haversine formula.distanceVincenty(Position $from, Position $to)
:
Calculates the geodetic distance between two points using the Vincenty inverse
formula for ellipsoids.use function Geokit\distanceHaversine;
use function Geokit\distanceVincenty;
$distance1 = distanceHaversine($from, $to);
$distance2 = distanceVincenty($from, $to);
Both functions return a Distance instance.
The circle()
function calculates a closed circle Polygon given a center,
radius and steps for precision.
use Geokit\Distance;
use Geokit\Position;
use function Geokit\circle;
$circlePolygon = circle(
Position::fromXY(8.50207515, 49.50042565),
Distance::fromString('5km'),
32
);
Other useful functions are:
heading(Position $from, Position $to)
: Calculates the (initial) heading from
the first point to the second point in degrees.midpoint(Position $from, Position $to)
: Calculates an intermediate point on
the geodesic between the two given points.endpoint(Position $start, float $heading, Geokit\Distance $distance)
:
Calculates the destination point along a geodesic, given an initial heading
and distance, from the given start point.Copyright (c) 2011-2020 Jan Sorgalla. Released under the MIT License.