javascript 通过坐标检查半径

Posted 2021-05-04

function arePointsNear(checkPoint, centerPoint, km) {
    var ky = 40000 / 360;
    var kx = Math.cos(Math.PI * centerPoint.lat / 180.0) * ky;
    var dx = Math.abs(centerPoint.lng - checkPoint.lng) * kx;
    var dy = Math.abs(centerPoint.lat - checkPoint.lat) * ky;
    return Math.sqrt(dx * dx + dy * dy) <= km;
}

var vasteras = { lat: 59.615911, lng: 16.544232 };
var stockholm = { lat: 59.345635, lng: 18.059707 };

var n = arePointsNear(vasteras, stockholm, 2000);

console.log(n);