public static function fromCenterAndDistance(GeolocationInterface $center, Distance $distance)
{
$radLat = deg2rad($center->getLat());
$radLon = deg2rad($center->getLong());
// angular distance in radians on a great circle
$radDist = $distance->getMeters() / GeolocationInterface::EARTH_RADIUS;
$minLat = $radLat - $radDist;
$maxLat = $radLat + $radDist;
$deltaLon = asin(sin($radDist) / cos($radLat));
$minLon = $radLon - $deltaLon;
//if (minLon < MIN_LON) {minLon += 2d * Math.PI;}
$maxLon = $radLon + $deltaLon;
//if (maxLon > MAX_LON) {maxLon -= 2d * Math.PI;}
$min = new Geolocation(rad2deg($maxLat), rad2deg($minLon));
$max = new Geolocation(rad2deg($minLat), rad2deg($maxLon));
return new BoundingBox($min, $max);
}
/** @return Distance */
public function distanceTo(GeolocationInterface $otherGeolocation)
{
if (!$this->latRadians) {
$this->latRadians = deg2rad($this->lat);
}
if (!$this->longRadians) {
$this->longRadians = deg2rad($this->long);
}
$latFrom = $this->latRadians;
$lonFrom = $this->longRadians;
$latTo = deg2rad($otherGeolocation->getLat());
$lonTo = deg2rad($otherGeolocation->getLong());
$latDelta = $latTo - $latFrom;
$lonDelta = $lonTo - $lonFrom;
$angle = 2 * asin(sqrt(pow(sin($latDelta / 2), 2) + cos($latFrom) * cos($latTo) * pow(sin($lonDelta / 2), 2)));
return new Distance($angle * GeolocationInterface::EARTH_RADIUS);
}
