README

强烈建议您在 https://www.mullie.eu/geographic-searches/ 阅读一些背景信息

用法

查找Kortrijk火车站10公里范围内的任何事物

Geo 类特别适合进行基于距离的简单计算

$geo = new Geo\Geo('km');

// coord of Kortrijk railway station
$coord = new Geo\Coordinate(50.824167, 3.263889);

// calculate bounding box of 10km around this coordinate
$bounds = $geo->bounds($coord, 10);

/*
 * Now pass this on this the database, so it executes a query like:
 *     SELECT *
 *     FROM coordinates
 *     WHERE
 *         lat BETWEEN :swlat AND :nelat
 *         lng BETWEEN :swlng AND :nelng
 *
 * :swlat being $bounds->sw->latitude
 * :swlng being $bounds->sw->longitude
 * :nelat being $bounds->ne->latitude
 * :nelng being $bounds->ne->longitude
 *
 * Assume we have the database results in a variable called $results
 */

// now weed out entries that fit in the bounding box, but not exactly in
// the radius we want them to be in
foreach ($results as $i => $result) {
    $resultCoord = new Geo\Coordinate($result['lat'], $result['lng']);

    // actual distance between source coordinate & result from DB
    $distance = $geo->distance($coord, $resultCoord);

    // if distance is too large, get rid of the result
    if ($distance > 10) {
        unset($results[$i]);
    }
}

聚类坐标

当处理大量地点时，Clusterer 类可能很有用。例如，您想在地图上显示成千上万的地点。Google Maps（可能还有其他）也可以创建簇，但您仍然需要将所有地点传递到前端。而不是输出所有坐标并等待完整列表加载，我们可以在PHP中完成聚类，并向您的客户端提供更轻量级的坐标选择！

$clusterer = new Geo\Clusterer(
    // your viewport: in this case an approximation of bounding box around Belgium
    new Geo\Bounds(
        new Geo\Coordinate(51.474654, 6.344604),
        new Geo\Coordinate(49.482639, 2.471924)
    )
);

// create a matrix of about 12 cells (this may differ from 12, depending on
// the exact measurements of the bounding box)
$clusterer->setNumberOfClusters(12);

// start clustering after 2 locations in the same cell
$clusterer->setMinClusterLocations(2);

// add locations to clusterer
$clusterer->addCoordinate(new Geo\Coordinate(50.824167, 3.263889)); // Kortrijk railway station
$clusterer->addCoordinate(new Geo\Coordinate(51.035278, 3.709722)); // Gent-Sint-Pieters railway station
$clusterer->addCoordinate(new Geo\Coordinate(50.881365, 4.715682)); // Leuven railway station
$clusterer->addCoordinate(new Geo\Coordinate(50.860526, 4.361787)); // Brussels North railway station
$clusterer->addCoordinate(new Geo\Coordinate(50.836712, 4.337521)); // Brussels South railway station
$clusterer->addCoordinate(new Geo\Coordinate(50.845466, 4.357113)); // Brussels Central railway station
$clusterer->addCoordinate(new Geo\Coordinate(51.216227, 4.421180)); // Antwerpen Central railway station

// now get the results...
$clusterer->getClusters(); // returns 1 cluster: all 3 Brussels stations
$clusterer->getCoordinates(); // returns 4 non-clustered coordinates

安装

如果您使用 Composer 管理项目依赖，只需在 composer.json 文件中添加对 matthiasmullie/geo 的依赖即可

composer require matthiasmullie/geo

尽管建议使用 Composer，但实际上您可以选择任何方式包含这些文件。

许可协议

Geo 是 MIT 许可。