openlayers 入门教程（十二）：定位与轨迹-白红宇

openlayers 入门教程（十二）：定位与轨迹

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发布时间：2023-02-23

本文共 2041 字，大约阅读时间需要 6 分钟。

Openlayers ??? GIS ??????????

1. Openlayers ??? GIS ????

Openlayers ?????????? GISWeb????????????????????????? Leaflet?Cesium ????Openlayers ??????????????????????????????????

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- Openlayers ????? WebGL ??????????????????
- Leaflet ?????????????????????????
- Cesium ???3D???? Openlayers ?2D???????????
- MapboxGL ????????????? Openlayers ?????????

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- Openlayers ????????????????????????????
- Leaflet ?????????????????????????
- Cesium ?????3D???????????????????
- MapboxGL ??????????????????????????????

2. Openlayers ?????Geolocation?????

? Openlayers ????????Geolocation?API??????????????????????????

if (navigator.geolocation) {    navigator.geolocation.watchPosition(function(position) {        var coordinate = ol.proj.transform([            position.coords.longitude,            position.coords.latitude        ], 'EPSG:4326', 'EPSG:3857');        if (marker) {            marker.setPosition(coordinate);        } else {            marker = new ol.Feature({                geometry: new ol.geom.Point(coordinate)            });            vectorSource.addFeature(marker);        }    }, function(error) {        console.error('Error getting geolocation:', error.message);    });}

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??????GPS???EPSG:4326???? Openlayers ??? Web Mercator ???EPSG:3857??

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3. Openlayers ?????Track Drawing?

? Openlayers ???????????? LineString ???????????????????

var trackLineString = new ol.geom.LineString([]);trackLineString.appendCoordinate(coordinate);var trackFeature = new ol.Feature({    geometry: trackLineString});var vectorSource = new ol.source.Vector({    features: [trackFeature]});var vectorLayer = new ol.layer.Vector({    source: vectorSource});map.addLayer(vectorLayer);

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