微信小程序map地图画圆圈效果

 

// map.js
var EARTH_RADIUS = 6378.137; //地球半径

function rad(d) {return d * Math.PI / 180.0;
}
function getDistance(lng1, lat1, lng2, lat2) {var radLat1 = rad(lat1);var radLat2 = rad(lat2);var a = radLat1 - radLat2;var b = rad(lng1) - rad(lng2);var s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2)+ Math.cos(radLat1) * Math.cos(radLat2)* Math.pow(Math.sin(b / 2), 2)));s = s * EARTH_RADIUS;s = Math.round(s * 10000) / 10000;return s;//返回数值单位：公里
}Page({data: {markers:[{iconPath: '/resources/others.png',id: 0