谷歌地图获取坐标系米

Question

正在做什么

尝试做的是，让用户使用google drawingManager在Google地图上绘制多边形，然后将该多边形转移到threejs中的3D地面上。

问题

我试图在threejs 3D场景中定义顶点，但是我需要在公制坐标系中定义x和y，我可以从谷歌地图中的latlng，世界，点坐标系中获取多边形点，但是如何将这些坐标转换为公制坐标系：\？

代码

let map;
        let paths;
        let edges = [];
        let points = [];
        let edgesByPoints = [];

        function initMap() {
            map = new google.maps.Map(document.getElementById('map'), {
                center: {lat: 31.984868, lng: 36.027031},
                zoom: 18
            });

            var drawingManager = new google.maps.drawing.DrawingManager({
                drawingControlOptions: {
                    drawingModes: [
                        google.maps.drawing.OverlayType.POLYGON,
                    ]
                }
            });
            drawingManager.setMap(map);

            google.maps.event.addListener(drawingManager, 'polygoncomplete', function (polygon) {

                paths = polygon.getPath().j;

                for (let i = 0; i < paths.length; i++) {
                    let nextPath = (i + 1 >= paths.length) ? paths[0] : paths[i + 1];
                    edges[i] = getDistance(paths[i], nextPath);

                    // let latlng = new google.maps.LatLng(paths[i].lat(),paths[i].lng());
                    // console.log(paths[i].lat());
                    points[i] = map.getProjection().fromLatLngToPoint(paths[i]);
                    let nextPoint = map.getProjection().fromLatLngToPoint(nextPath);

                    edgesByPoints[i] = findDistance(points[i],nextPoint);
                }
            });
        }

        // a function that I made to calculate the distance between points
        function findDistance(point1,point2) {
            return Math.sqrt(Math.pow((point1.x - point2.x),2) + Math.pow((point1.y - point2.y),2));
        }

        var rad = function (x) {
            return x * Math.PI / 180;
        };

        // a function that i found in the internet, it get the distance right but, I need to find the coordinates not just the distance between points.
        var getDistance = function (p1, p2) {
            var R = 6378137; // Earth’s mean radius in meter
            var dLat = rad(p2.lat() - p1.lat());
            var dLong = rad(p2.lng() - p1.lng());
            var a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
                Math.cos(rad(p1.lat())) * Math.cos(rad(p2.lat())) *
                Math.sin(dLong / 2) * Math.sin(dLong / 2);
            var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
            return R * c; // returns the distance in meter
        };

        // i don't know but the result from this function seem to be incorrect
        function latLng2Point(latLng, map) {
            var topRight = map.getProjection().fromLatLngToPoint(map.getBounds().getNorthEast());
            var bottomLeft = map.getProjection().fromLatLngToPoint(map.getBounds().getSouthWest());
            var scale = Math.pow(2, map.getZoom());
            var worldPoint = map.getProjection().fromLatLngToPoint(latLng);
            return new google.maps.Point((worldPoint.x - bottomLeft.x) * scale, (worldPoint.y - topRight.y) * scale);
        }