百度地图根据经纬度坐标值绘制轨迹.

var map = new BMap.Map("map");
var point = new BMap.Point(116.404, 39.915);
map.centerAndZoom(point, 15);
map.enableScrollWheelZoom(); // 开启鼠标滚轮缩放
map.addControl(new BMap.ScaleControl()); // 添加比例尺控件

var pointStr = "104.038748,30.641821,104.047789,30.648128,104.063959,30.655336,104.067264,30.660307,104.067264,30.664438,104.064008,30.665316".split(",");
var pointArr = [];

for (var k = 0; k < pointStr.length; k += 2) {
pointArr.push({
lng: pointStr[k],
lat: pointStr[k + 1]
});
}

// 生成坐标点
var trackPoint = [];
for (var i = 0, j = pointArr.length; i < j; i++) {
trackPoint.push(new BMap.Point(pointArr[i].lng, pointArr[i].lat));
}

map.centerAndZoom(trackPoint[0], 15);

// 画线
var polyline = new BMap.Polyline(trackPoint, {
strokeColor: "#1869AD",
strokeWeight: 3,
strokeOpacity: 1
});
map.addOverlay(polyline);

// 配置图片
var size = new BMap.Size(26, 26);
var offset = new BMap.Size(0, -13);
var imageSize = new BMap.Size(26, 26);
var icon = new BMap.Icon("./express-position.png", size, {
imageSize: imageSize
});

// 画图标
for (var i = 0, j = trackPoint.length; i < j; i++) {
var marker = new BMap.Marker(trackPoint[i], {
icon: icon,
offset: offset
}); // 创建标注
map.addOverlay(marker);

}

//根据经纬极值计算绽放级别。 (从网上复制)
function getZoom(maxLng, minLng, maxLat, minLat) {
var zoom = ["50", "100", "200", "500", "1000", "2000", "5000", "10000", "20000", "25000", "50000", "100000", "200000", "500000", "1000000", "2000000"]; // 级别18到3。
var pointA = new BMap.Point(maxLng, maxLat); // 创建点坐标A
var pointB = new BMap.Point(minLng, minLat); // 创建点坐标B
var distance = map.getDistance(pointA, pointB).toFixed(1); //获取两点距离,保留小数点后两位
for (var i = 0, zoomLen = zoom.length; i < zoomLen; i++) {
if (zoom[i] - distance > 0) {
return 18 - i + 3; //之所以会多3，是因为地图范围常常是比例尺距离的10倍以上。所以级别会增加3。
}
}
}

// (从网上复制)
function setZoom(points) {
if (points.length > （http://www.amjmh.com/v/BIBRGZ_558768/）0) {
var maxLng = points[0].lng;
var minLng = points[0].lng;
var maxLat = points[0].lat;
var minLat = points[0].lat;
var res;
for (var i = points.length - 1; i >= 0; i--) {
res = points[i];
if (res.lng > maxLng) maxLng = res.lng;
if (res.lng < minLng) minLng = res.lng;
if (res.lat > maxLat) maxLat = res.lat;
if (res.lat < minLat) minLat = res.lat;
}
var cenLng = (parseFloat(maxLng) + parseFloat(minLng)) / 2;
var cenLat = (parseFloat(maxLat) + parseFloat(minLat)) / 2;
var zoom = getZoom(maxLng, minLng, maxLat, minLat);
map.centerAndZoom(new BMap.Point(cenLng, cenLat), zoom);
} else {
//没有坐标，显示全中国
map.centerAndZoom(new BMap.Point(103.388611, 35.563611), 5);
}
}

setZoom(pointArr)

原文地址：https://www.cnblogs.com/ly570/p/11488509.html