OpenLayers学习笔记(十)— 动态加载JSON数据模拟航迹线
在openlayers 3 上,加载本地json数据,动态绘制航迹线,以飞机当前位置为地图中心,此例子是模拟DEMO
本文链接:动态加载JSON数据模拟航迹线
作者:狐狸家的鱼
GitHub:八至
前提需求
需要以JSON数据动态加载绘制飞机轨迹线,飞机图标以加载的坐标为当前实时位置,经过的坐标追加到轨迹线上,标牌始终跟随飞机移动。
简单搭建本地服务器
因为要加载本地JSON文件,可能会存在跨域问题,所以在本地搭建一个服务器来加载数据,会更加方便。
1.全局安装http-server
npm install http-server -g
右键菜单添加cmd窗口
这是题外话,只是为了打开方便,在右键菜单中加入”在此处打开命令窗口“
参考这个,步骤:
- 随便在哪里新建一个txt文件,命名为OpenCmdHere.txt
- 在文件中输入如下代码,并保存
- 更改文件后缀名为reg,弹出的提示点确认
- 双击OpenCmdHere.reg文件运行,弹出的提示点确认,修改注册表就大功告成了
Windows Registry Editor Version 5.00 [HKEY_CLASSES_ROOT\Directory\shell\OpenCmdHere] @="在此处打开命令窗口" "Icon"="cmd.exe" [HKEY_CLASSES_ROOT\Directory\shell\OpenCmdHere\command] @="cmd.exe /s /k pushd "%V"" [HKEY_CLASSES_ROOT\Directory\Background\shell\OpenCmdHere] @="在此处打开命令窗口" "Icon"="cmd.exe" [HKEY_CLASSES_ROOT\Directory\Background\shell\OpenCmdHere\command] @="cmd.exe /s /k pushd \"%V\"" [HKEY_CLASSES_ROOT\Drive\shell\OpenCmdHere] @="在此处打开命令窗口" "Icon"="cmd.exe" [HKEY_CLASSES_ROOT\Drive\shell\OpenCmdHere\command] @="cmd.exe /s /k pushd \"%V\"" [HKEY_CLASSES_ROOT\LibraryFolder\background\shell\OpenCmdHere] @="在此处打开命令窗口" "Icon"="cmd.exe" [HKEY_CLASSES_ROOT\LibraryFolder\background\shell\OpenCmdHere\command] @="cmd.exe /s /k pushd \"%V\""
启动服务器
进入map文件夹,右键打开cmd窗口,输入命令:
http-server
就像这样:
服务器就启动了,文件夹里的所有数据都可以加载了。在浏览器里输入http://192.168.1.126:8080或者http://127.0.0.1:8080都可以加载。
效果实现
1.初始化地图和图层
(1)图层以及样式
/** * @name: 相关样式和图层:点 航迹线 飞机 标牌 * @msg: * @param {type} * @return: */ //样式 let route_style = new ol.style.Style({ stroke:new ol.style.Stroke({ width:2, color: '#007cbf' }), zIndex:2 }); //创建轨迹线 let trackLine = new ol.geom.LineString([]); //矢量图层层 let aircfaftLayer = new ol.layer.Vector({ source:new ol.source.Vector(), }) let flightTrackLayer = new ol.layer.Vector({ source:new ol.source.Vector({ features:[ new ol.Feature({ geometry:trackLine }) ] }), style:route_style, updateWhileInteracting: true,//拖拽时自动更新位置 顺滑拖拽 }); /* * @name: 初始化地图 * @description: * @param {type} none * @return: */ const center = new ol.proj.fromLonLat([104.06250000000001, 30.65681556429287]); //地图 let map = new ol.Map({ //图层顺序自下而上 layers: [ new ol.layer.Tile({ source: new ol.source.OSM({ }) }),flightTrackLayer,aircfaftLayer, ], renderer: 'canvas', target: 'map', view: new ol.View({ center: center, zoom: 6 }) });
(2)创建元素(图标、标注信息叠加层)
/** * @name: 飞机 标牌 航迹 * @description: * @param {type} none * @return: */ //标牌叠加层 let markerEl = document.getElementById('geo-marker'); let marker = new ol.Overlay({ positioning: 'bottom-center', stopEvent: false, dragging: false, offset: [0, 0], element: markerEl, stopEvent: false }); map.addOverlay(marker); //飞机图标样式 function createGoodStyle(aircraftNum) { return new ol.style.Style({ image:new ol.style.Circle({ radius:4, snapToPixel:false, fill:new ol.style.Fill({ color:'yellow' }), stroke:new ol.style.Stroke({ color:"#333", width:2 }) }) }); }
//设置地图中心 let centerAir = val => { map.getView().setCenter(val); }
(3)动态加载数据
/** * @name: 加载数据 * @description: * @param {type} none * @return: */ //添加飞机 + 更新位置 let coords, intervalId, interval = 1000, i = 0; const url = './data/flight.json'; let theAirplane = new ol.Feature([]); $('.startAnimate').click(() => { //加载坐标数据 $.ajax({ url: url, dataType: 'json', success: function (response) { console.log(response); coords = response.coordinates; label = response.aircraftNum; // 飞机 let position = ol.proj.fromLonLat(coords[0]); //飞机 theAirplane.setId(response.aircraftNum); theAirplane.set("speed", response.speed); theAirplane.setStyle(createGoodStyle(response.aircraftNum)); theAirplane.getStyle().getImage().setRotation(response.rotation); aircfaftLayer.getSource().addFeature(theAirplane); //航迹线和标牌 intervalId = setInterval(() => { position = ol.proj.fromLonLat(coords[i]); //标牌 marker.setPosition(position); markerEl.innerHTML = response.aircraftNum;//简标牌//航迹 let point = new ol.proj.transform(coords[i], 'EPSG:4326', 'EPSG:3857'); trackLine.appendCoordinate(point); //以当前位置为地图中心 centerAir(position); i++; if(i === coords.length) { clearInterval(intervalId);//停止循环 } }, interval); } }) })
(4)json数据
json数据来源于arc.js,该例子选取的是成都—上海的坐标数据:
{
"ID":"1",
"aircraftNum": "B000",
"speed":"25",
"rotation":"114",
"coordinates": [
[104.06250000000001, 30.65681556429287],
[104.23659653944907, 30.67396833485058],
[104.4107544999246, 30.690888911014596],
[104.58497310591778, 30.70757705503652],
[104.75925157857333, 30.724032532190993],
[104.93358913572729, 30.740255110788784],
[105.10798499194534, 30.75624456218971],
[105.28243835856125, 30.772000660815337],
[105.45694844371592, 30.787523184161603],
[105.63151445239656, 30.80281191281125],
[105.80613558647657, 30.817866630446186],
[105.98081104475536, 30.8326871238596],
[106.15554002299895, 30.847273182967992],
[106.33032171398055, 30.861624600823],
[106.50515530752187, 30.875741173623137],
[106.68003999053437, 30.889622700725297],
[106.85497494706121, 30.90326898465615],
[107.02995935831927, 30.916679831123393],
[107.20499240274177, 30.929855049026738],
[107.38007325602092, 30.942794450468945],
[107.55520109115115, 30.95549785076639],
[107.73037507847249, 30.967965068459744],
[107.90559438571445, 30.98019592532436],
[108.08085817803996, 30.992190246380456],
[108.25616561808987, 31.003947859903253],
[108.43151586602752, 31.01546859743276],
[108.60690807958395, 31.026752293783623],
[108.7823414141029, 31.0377987870545],
[108.9578150225866, 31.0486079186376],
[109.13332805574153, 31.059179533227734],
[109.30887966202457, 31.069513478831404],
[109.48446898768944, 31.079609606775563],
[109.66009517683327, 31.089467771716325],
[109.83575737144373, 31.099087831647413],
[110.011454711446, 31.108469647908397],
[110.18718633475038, 31.11761308519283],
[110.36295137729994, 31.126518011556165],
[110.53874897311843, 31.135184298423425],
[110.7145782543585, 31.14361182059676],
[110.89043835135004, 31.151800456262833],
[111.06632839264884, 31.1597500869999],
[111.24224750508553, 31.16746059778481],
[111.4181948138144, 31.17493187699975],
[111.5941694423629, 31.182163816438862],
[111.77017051268102, 31.18915631131456],
[111.94619714519094, 31.195909260263747],
[112.1222484588369, 31.202422565353807],
[112.29832357113521, 31.208696132088367],
[112.47442159822452, 31.21472986941292],
[112.65054165491617, 31.220523689720157],
[112.82668285474469, 31.226077508855244],
[113.00284431001862, 31.231391246120737],
[113.17902513187131, 31.236464824281384],
[113.35522443031194, 31.241298169568736],
[113.53144131427662, 31.245891211685535],
[113.70767489167979, 31.250243883809823],
[113.88392426946552, 31.254356122599024],
[114.0601885536591, 31.258227868193615],
[114.23646684941869, 31.26185906422076],
[114.41275826108706, 31.265249657797618],
[114.58906189224348, 31.268399599534526],
[114.76537684575561, 31.271308843537938],
[114.94170222383167, 31.27397734741316],
[115.11803712807243, 31.276405072266883],
[115.2943806595235, 31.27859198270948],
[115.47073191872758, 31.28053804685718],
[115.64709000577683, 31.282243236333912],
[115.82345402036526, 31.28370752627301],
[115.99982306184107, 31.284930895318737],
[116.17619622925929, 31.285913325627515],
[116.35257262143426, 31.28665480286904],
[116.52895133699217, 31.28715531622708],
[116.70533147442355, 31.28741485840016],
[116.8817121321361, 31.28743342560202],
[117.0580924085071, 31.28721101756178],
[117.23447140193603, 31.286747637524012],
[117.41084821089731, 31.286043292248515],
[117.58722193399282, 31.285097992009906],
[117.76359167000443, 31.283911750597046],
[117.93995651794664, 31.282484585312172],
[118.11631557711907, 31.280816516969885],
[118.29266794715906, 31.278907569895903],
[118.46901272809394, 31.276757771925578],
[118.64534902039362, 31.27436715440231],
[118.82167592502275, 31.271735752175562],
[118.99799254349321, 31.268863603598895],
[119.17429797791613, 31.26575075052759],
[119.35059133105422, 31.262397238316204],
[119.52687170637368, 31.258803115815805],
[119.70313820809623, 31.254968435371172],
[119.87938994125103, 31.250893252817523],
[120.05562601172639, 31.2465776274773],
[120.2318455263214, 31.242021622156606],
[120.40804759279759, 31.237225303141468],
[120.58423131993031, 31.232188740193873],
[120.76039581756008, 31.226912006547636],
[120.93654019664363, 31.221395178904057],
[121.11266356930511, 31.215638337427364],
[121.28876504888679, 31.20964156573994],
[121.46484375, 31.203404950917395]
]
}
加载完成后效果如下:
后续要完成的就是以飞机当前速度和航线预测未来5分钟所在的坐标位置,以及拖拽标注信息叠加层
查看源码:GitHub