基于Cesium开源框架的3D展示（包含加载三维以及地图的一些基本操作）_cesuim 加载面3d效果-程序员宅基地
技术标签： cesium
白驹过隙，时光如梭，又到一年年尾。回想一年的工作，感觉做了很多，又感觉什么都没做成。so，在此回顾一下今年经历过的那些个不一定有头，不一定有尾的项目经历。今天讲讲Cesium。
我是个随性的人，想到哪里讲到哪里，但是逻辑还是很清晰的，细节即是如此。
Cesium是一个很强大的3D框架，很多大公司的底层框架都基于此。so自己实践做了一些实验，对Cesium做了比较详细的了解，并简单实现了测面、测距、加载各种格式的数据（.geojson 3Dtile .kml .czml等格式）。废话不多说，具体了解一下。
首先是Cesium开发包的引入，直接在Cesium的官网上下载就好了，然后新建的项目在项目的Apps里面存放即可。
头部导入.js类
<!-- script部分 -->
<script src="../../../Build/Cesium/Cesium.js"></script>初始化Cesium界面
var viewer = new Cesium.Viewer('map_container', {
animation: false,
baseLayerPicker: false,
geocoder: true,
timeline: false,
sceneModePicker: true,
navigationHelpButton: false,
infoBox: true,
fullscreenButton:false,
vrButton:true,
homeButton:false,
selectionIndicator : false,//是否显示选取指示器组件
});
viewer._cesiumWidget._creditContainer.style.display = "none"; //去掉左下角那个不可爱的图标
// viewer.extend(Cesium.viewerCesiumInspectorMixin); //那些个特效
viewer.camera.setView({
destination:Cesium.Cartesian3.fromDegrees(111.07, 39.05, 20000000),
orientation:{
heading : Cesium.Math.toRadians(0),
pitch : Cesium.Math.toRadians(-90),
roll : Cesium.Math.toRadians(0) //heading、pitch和roll就是镜头相对于xyz轴的角度，比如pitch为-90°而另外两个为0时，就是90°向下俯视地球。
}
});new操作的时候，后面{}里面的item都是可选的，改成true or false都可以，都是些特效类，玩腻了，除了必要的，都不要了，例如baselayerPicker底图选择器，里面包含多种数据源（google的啦，bingMap）
加载底图（天地图的，找了好久才找到）
var layerone = viewer.scene.imageryLayers.addImageryProvider(new Cesium.WebMapTileServiceImageryProvider({
url: "http://t0.tianditu.com/img_w/wmts?service=wmts&request=GetTile&version=1.0.0&LAYER=img&tileMatrixSet=w&TileMatrix={TileMatrix}&TileRow={TileRow}&TileCol={TileCol}&style=default&format=tiles",
layer: "tdtImgBasicLayer",
style: "default",
format: "image/jpeg",
tileMatrixSetID: "GoogleMapsCompatible",
show: false
}));//卫星影像
// layerone.alpha = 0.3;
// layerone.brightness = 2.0;
var layertwo = viewer.scene.imageryLayers.addImageryProvider(new Cesium.WebMapTileServiceImageryProvider({
url: "http://t0.tianditu.com/cia_w/wmts?service=wmts&request=GetTile&version=1.0.0&LAYER=cia&tileMatrixSet=w&TileMatrix={TileMatrix}&TileRow={TileRow}&TileCol={TileCol}&style=default&format=tiles",
layer: "tdtImgAnnoLayer",
style: "default",
format: "image/jpeg",
tileMatrixSetID: "GoogleMapsCompatible",
show: false
}));//注记图层加载数据，不具体去分开了，因为我自己代码就是写在一起的，来个大集合，.geojson、.KML、tileset.json（3Dtile数据）
3Dtile是什么格式？该知道的总会知道，Cesium加载3Dtile
var URL_MODEL = "/officalCesium/Apps/baseData/";
$('#upLoadFile').change(function () {
var file = $('#upLoadFile').get(0).files[0];
var filename = file.name;
var t = filename.lastIndexOf(".");
var s = filename.substring(t+1,filename.length).toUpperCase();
var dataType = document.getElementById("typeInput");
var value = dataType.options[dataType.selectedIndex].value.toUpperCase();
$('#addLayerModal').modal('hide'); //隐藏对话框
if(s == value){
if(value == "GEOJSON"){
var filepath = URL_MODEL+filename;
var geosonView = viewer.dataSources.add(Cesium.GeoJsonDataSource.load(filepath,{
stroke: Cesium.Color.YELLOW, //设置为TRANSPARENT的时候，透明
fill: Cesium.Color.YELLOW,
strokeWidth: 5,
markerSymbol: '?',
}));
viewer.flyTo(geosonView);
// alert(filepath+"");
}
else if (value == "JSON" && filename.toUpperCase() == "TILESET.JSON"){
var filepath = URL_MODEL+filename;
var tileset = viewer.scene.primitives.add(new Cesium.Cesium3DTileset({
url: filepath, //数据路径
maximumScreenSpaceError: 2,//默认16,最大屏幕空间错误
//maximumNumberOfLoadedTiles: 1000,
maximumMemoryUsage:1024//默认512,内存MB的最大数量
}));
viewer.flyTo(tileset);
// alert(filepath+"");
}
else if(value == "KML"){
var filepath = URL_MODEL+filename;
var kml_view = Cesium.KmlDataSource.load(filepath);
viewer.flyTo(kml_view);
// alert(filepath+"");
}else if(value == "CZML"){
var filepath = URL_MODEL+filename;
var dataRecourse = new Cesium.CzmlDataSource(filepath);
dataRecourse.load();
viewer.dataSources.add(dataRecourse);
viewer.flyTo(data_resouce);
}
}else {
alert("上传失败，不是."+value+"类型的文件");
}
});
飞行、复位等实用工具如下：
//飞行到某个点
function dingwei(lon,lat,height){
viewer.camera.flyTo({
destination : Cesium.Cartesian3.fromDegrees(lon,lat,height), // 设置位置
orientation: {
heading : Cesium.Math.toRadians(20.0), // 方向
pitch : Cesium.Math.toRadians(-90.0),// 倾斜角度
roll : 0
},
duration:5, // 设置飞行持续时间，默认会根据距离来计算
complete: function () {
// 到达位置后执行的回调函数
console.log('到达目的地');
},
cancle: function () {
// 如果取消飞行则会调用此函数
console.log('飞行取消')
},
pitchAdjustHeight: -90, // 如果摄像机飞越高于该值，则调整俯仰俯仰的俯仰角度，并将地球保持在视口中。
maximumHeight:500, // 相机最大飞行高度
flyOverLongitude: 100, // 如果到达目的地有2种方式，设置具体值后会强制选择方向飞过这个经度
});
}
//复位地图
function clearMap(){
// dingwei(115.446105254,22.771558650,2000);
viewer.flyTo(tileset);
clearAllPan();
}
//清空地图
function clearAll(){
clearAllPan();
}然后就是测距测面，测量分两种吧，一直贴地的，一种是3D的那种，贴地量算没问题，3D的我写的代码还是有问题。
//* 测距测面 */
var scene = viewer.scene;
var canvas = viewer.canvas;
var clock = viewer.clock;
var camera = viewer.scene.camera;
//布尔型变量
var isPoint = false;
var isPolyline = false;
var isPolygon_line = false;
//是否开始绘制标识
var isStartDraw = false;
var isclear = false;
var points = viewer.entities.add(new Cesium.Entity());
var polylines = viewer.entities.add(new Cesium.Entity());
var Polygons_Line = viewer.entities.add(new Cesium.Entity());
//画多边形过程中展示的线最后要移除或者不显示
var Polygon_Lines_remove = viewer.entities.add(new Cesium.Entity());
var ellipsoid = scene.globe.ellipsoid;
canvas.onclick = function () {
canvas.focus();
};
var handler = new Cesium.ScreenSpaceEventHandler(canvas);
viewer.zoomTo(viewer.entities);
defaultZoomAmount_ = 3000000.0;
var lastPointLon = -999.0;
var lastPointLat = -999.0;
var firstPointLon = -999.0;
var firstPointLat = -999.0;
var measurePointsArray=new Array();
measurePointsArray.splice(0,measurePointsArray.length);
var endCartographic = new Cesium.Cartographic();
var geodesic = new Cesium.EllipsoidGeodesic();
var PolygonPointArray_line = null;
var PolygonPointArray_fill = null;
//鼠标移动时的那条线
var moveLine_first = viewer.entities.add({
id: "moveLine_first",
name: 'line on the surface',
polyline: {
show: false,
width: 2,
material: Cesium.Color.WHITE
}
});
var moveLine_second = viewer.entities.add({
id: "moveLine_second",
name: 'line on the surface',
polyline: {
show: false,
width: 2,
material: Cesium.Color.WHITE
}
});
/* handler.setInputAction(function(){},
Cesium.ScreenSpaceEventType.LEFT_DOUBLE_CLICK);*/
//鼠标移动时做的操作
handler.setInputAction(function (movement) {
//捕获椭球体，将笛卡尔二维平面坐标转为椭球体的笛卡尔三维坐标，返回球体表面的点
var cartesian=viewer.camera.pickEllipsoid(movement.endPosition, ellipsoid);
if(cartesian) {
//将笛卡尔三维坐标转为地图坐标（弧度）
var cartographic = viewer.scene.globe.ellipsoid.cartesianToCartographic(cartesian);
//将地图坐标（弧度）转为十进制的度数
var lat_String = Cesium.Math.toDegrees(cartographic.latitude).toFixed(4);
var log_String = Cesium.Math.toDegrees(cartographic.longitude).toFixed(4);
var alti_String = (viewer.camera.positionCartographic.height / 1000).toFixed(2);
longitude_show.innerHTML = log_String;
latitude_show.innerHTML = lat_String;
altitude_show.innerHTML = alti_String;
}
}, Cesium.ScreenSpaceEventType.MOUSE_MOVE);
function clearAllPan() {
viewer.entities.removeAll();
isStartDraw = false;
isclear = true;
document.body.style.cursor = "pointer";
document.getElementById("map_container").style.cursor = "pointer";
handler.setInputAction(function(){
},Cesium.ScreenSpaceEventType.LEFT_CLICK);
}
var QQ=0;
function clearAllPan1(id) {
if(id!=undefined){
var tempmark = viewer.entities.getById(id);
viewer.entities.remove(tempmark);
}
QQ=1;
}
//双击停止加线面
function shuangji(){
isPolyline = false;
isPolygon_line = false;
isPolygon_fill = false;
isStartDraw = false;
}
//加点
function addPoint() {
isPoint = true;
isPolyline = false;
isPolygon_line = false;
isPolygon_fill = false;
isStartDraw = false;
QQ=0;
}
//加线
function measureLength() {
var select_measure = document.getElementById("selOpt");
var value_measure = select_measure.options[select_measure.selectedIndex].value;
if(value_measure == 2){
isPoint = false;
isPolyline = true;
isPolygon_line = false;
isPolygon_fill = false;
isStartDraw = false;
QQ=0;
document.body.style.cursor = "url(resource/pic/icons/magnifier3.cur) 12 12,crosshair";
document.getElementById("map_container").style.cursor = "url(resource/pic/icons/magnifier3.cur) 12 12,crosshair";
addOnClickListener();
}
}
function addOnClickListener(){
handler.setInputAction(function(){},
Cesium.ScreenSpaceEventType.LEFT_DOUBLE_CLICK);
//鼠标移动时做的操作
handler.setInputAction(function (movement) {
if (isPolyline || isPolygon_line ) {
var cartesian = viewer.camera.pickEllipsoid(movement.endPosition, scene.globe.ellipsoid);
if (cartesian && isStartDraw) {
//做清除工作把全局变量moveLine清除掉了 ，需要重新加到entities上 否则显示不正常
if (isclear) {
viewer.entities.add(moveLine_first);
viewer.entities.add(moveLine_second);
isclear = false;
}
var cartographic = Cesium.Cartographic.fromCartesian(cartesian);
var curMovementLon = Cesium.Math.toDegrees(cartographic.longitude).toFixed(12);
var curMovementLat = Cesium.Math.toDegrees(cartographic.latitude).toFixed(12);
viewer.entities.getById("moveLine_first").polyline.positions = Cesium.Cartesian3.fromDegreesArray([lastPointLon, lastPointLat ,curMovementLon,
curMovementLat]);//修改属性
viewer.entities.getById("moveLine_first").polyline.show = true;
if (PolygonPointArray_line != null) {
if (PolygonPointArray_line.length >= 3) {
viewer.entities.getById("moveLine_second").polyline.positions = Cesium.Cartesian3.fromDegreesArray([curMovementLon, curMovementLat, firstPointLon, firstPointLat]);//修改属性
viewer.entities.getById("moveLine_second").polyline.show = true;
}
}
}
}
//捕获椭球体，将笛卡尔二维平面坐标转为椭球体的笛卡尔三维坐标，返回球体表面的点
var cartesian=viewer.camera.pickEllipsoid(movement.endPosition, ellipsoid);
if(cartesian){
//将笛卡尔三维坐标转为地图坐标（弧度）
var cartographic=viewer.scene.globe.ellipsoid.cartesianToCartographic(cartesian);
//将地图坐标（弧度）转为十进制的度数
var lat_String=Cesium.Math.toDegrees(cartographic.latitude).toFixed(4);
var log_String=Cesium.Math.toDegrees(cartographic.longitude).toFixed(4);
var alti_String=(viewer.camera.positionCartographic.height/1000).toFixed(2);
longitude_show.innerHTML=log_String;
latitude_show.innerHTML=lat_String;
altitude_show.innerHTML=alti_String;
}
}, Cesium.ScreenSpaceEventType.MOUSE_MOVE);
//鼠标左击做的操作
handler.setInputAction(function (click) {
if(QQ==1){
var pickedObject = viewer.scene.pick(click.position);
if (Cesium.defined(pickedObject) && (pickedObject.id != undefined)) {
actEntity = pickedObject.id;
clearAllPan1(actEntity._id);
}
}
if (isPoint || isPolyline || isPolygon_line ) {
var cartesian = viewer.camera.pickEllipsoid(click.position, scene.globe.ellipsoid);
if (cartesian) {
var cartographic = Cesium.Cartographic.fromCartesian(cartesian);
var currentClickLon = Cesium.Math.toDegrees(cartographic.longitude).toFixed(12);
var currentClickLat = Cesium.Math.toDegrees(cartographic.latitude).toFixed(12);
/* var currentClickHeight = cartographic.height;
console.log(currentClickHeight); */
if (!isStartDraw) {
viewer.entities.add({
position: cartesian,
point: {
parent: points,
pixelSize: 5,
color: Cesium.Color.YELLOW
}
});
firstPointLon = currentClickLon;
firstPointLat = currentClickLat;
PolygonPointArray_line = null;
PolygonPointArray_fill = null;
measurePointsArray.splice(0,measurePointsArray.length);
// var startCartographic = Cesium.Cartographic.fromDegrees(firstPointLon, firstPointLat);
measurePointsArray.push(cartographic);
isStartDraw = true;
} else {
if (isPoint) {
viewer.entities.add({
position: cartesian,
point: {
parent: points,
pixelSize: 5,
color: Cesium.Color.YELLOW
}
});
}
if (isPolyline || isPolygon_line )
{
// endCartographic = Cesium.Cartographic.fromDegrees(currentClickLon, currentClickLat,currentClickHigh);
endCartographic = Cesium.Cartographic.fromDegrees(currentClickLon, currentClickLat);
console.log(endCartographic);
measurePointsArray.push(endCartographic);
var arrLength=measurePointsArray.length;
var tmpDis=0;
var sumDis=0;
for(var i=1;i<arrLength;i++)
{
geodesic.setEndPoints(measurePointsArray[i-1], measurePointsArray[i]);
tmpDis=Math.round(geodesic.surfaceDistance);
sumDis=sumDis+tmpDis;
}
if(sumDis>1000)
{
var polylineDis= (sumDis / 1000).toFixed(1) + " km";
}
else{
var polylineDis= sumDis + " m";
}
// console.log(dis);
viewer.entities.add({
parent: polylines,
polyline: {
// positions: Cesium.Cartesian3.fromDegreesArray([lastPointLon, lastPointLat,lastPointHigh, currentClickLon, currentClickLat,currentClickHigh]),
positions: Cesium.Cartesian3.fromDegreesArray([lastPointLon, lastPointLat, currentClickLon, currentClickLat]),
width: 2,
material: Cesium.Color.RED
},
label: {
text: polylineDis.toString(),
font: '20px SimHei ',
Width: 10,
style: Cesium.LabelStyle.FILL_AND_OUTLINE,
fillColor: Cesium.Color.YELLOW,
outlineColor : Cesium.Color.GRAY,
outlineWidth :5,
horizontalOrigin: Cesium.HorizontalOrigin.CENTER,
verticalOrigin: Cesium.VerticalOrigin.BOTTOM
},
/* label : {
// This callback updates the length to print each frame.
text: polylineDis.toString(),
font : '25px',
pixelOffset : new Cesium.Cartesian2(1, 20)
},*/
// position: Cesium.Cartesian3.fromDegrees(currentClickLon, currentClickLat,currentClickHigh)
position: Cesium.Cartesian3.fromDegrees(currentClickLon, currentClickLat)
});
viewer.entities.getById("moveLine_first").polyline.show = false;
viewer.entities.getById("moveLine_second").polyline.show = false;
}
}
//记录鼠标点击的当前位置 作为下一次画线的起始点位置
lastPointLon = currentClickLon;
lastPointLat = currentClickLat;
// lastPointHigh = currentClickHigh;
if (isPolygon_line) {
if (PolygonPointArray_line == null)
PolygonPointArray_line = new Array();
PolygonPointArray_line.push(currentClickLon);
PolygonPointArray_line.push(currentClickLat);
// PolygonPointArray_line.push(currentClickHigh);
}
}
}
}, Cesium.ScreenSpaceEventType.LEFT_CLICK);
//鼠标双击时做的操作
handler.setInputAction(function (click)
{
if (isPolyline || isPolygon_line )
{
var cartesian = viewer.camera.pickEllipsoid(click.position, scene.globe.ellipsoid);
if (cartesian && isStartDraw)
{
var cartographic = Cesium.Cartographic.fromCartesian(cartesian);
var endPointLon = Cesium.Math.toDegrees(cartographic.longitude).toFixed(12);
var endPointLat = Cesium.Math.toDegrees(cartographic.latitude).toFixed(12);
var endPointHigh = Cesium.Math.toDegrees(cartographic.height).toFixed(12);
measurePointsArray.push(cartographic);
var arrLength=measurePointsArray.length;
var tmpDis=0;
var sumDis=0;
for(var i=1;i<arrLength;i++)
{
geodesic.setEndPoints(measurePointsArray[i-1], measurePointsArray[i]);
tmpDis=Math.round(geodesic.surfaceDistance);
sumDis=sumDis+tmpDis;
}
//考虑多边形最后显示距离
geodesic.setEndPoints(measurePointsArray[0], measurePointsArray[arrLength-1]);
tmpDis=Math.round(geodesic.surfaceDistance);
sumDis1=sumDis+tmpDis;
if(sumDis>1000)
{
var polylineDis= (sumDis / 1000).toFixed(1) + " km";
var polygonDis = (sumDis1 / 1000).toFixed(1) + " km";
}
else{
var polylineDis= (sumDis) + " m";
var polygonDis = (sumDis1) + " m";
}
if (isPolyline || isPolygon_line )
{
//画末线段
viewer.entities.add({
name: 'line on the surface',
parent: polylines,
polyline: {
positions: Cesium.Cartesian3.fromDegreesArray([lastPointLon, lastPointLat, endPointLon, endPointLat]),
width: 5,
material: Cesium.Color.RED
},
label: {
text: polylineDis.toString(),
font: '20px SimHei ',
Width: 10,
style: Cesium.LabelStyle.FILL_AND_OUTLINE,
fillColor: Cesium.Color.YELLOW,
outlineColor : Cesium.Color.GRAY,
outlineWidth :5,
horizontalOrigin: Cesium.HorizontalOrigin.CENTER,
verticalOrigin: Cesium.VerticalOrigin.BOTTOM
},
/*label : {
// This callback updates the length to print each frame.
text: polylineDis.toString(),
font : '25px',
pixelOffset : new Cesium.Cartesian2(1, 20)
},*/
position: Cesium.Cartesian3.fromDegrees(endPointLon, endPointLat)
});
if ( isPolygon_line )
{
viewer.entities.add({
name: 'line on the surface',
parent: polylines,
polyline: {
positions: Cesium.Cartesian3.fromDegreesArray([endPointLon, endPointLat, firstPointLon, firstPointLat]),
width: 5,
material: Cesium.Color.RED
}
});
viewer.entities.getById("moveLine_second").polyline.show = false;
}
viewer.entities.getById("moveLine_first").polyline.show = false;
}
//画多边形 不带填充
if (isPolygon_line)
{
if (PolygonPointArray_line != null) {
PolygonPointArray_line.push(endPointLon);
PolygonPointArray_line.push(endPointLat);
}
//当多边形数组中点的个数大于等于3时添加多边形
if (PolygonPointArray_line.length >= 3) {
viewer.entities.add({
name: 'polygon on surface',
polygon: {
hierarchy: Cesium.Cartesian3.fromDegreesArray(PolygonPointArray_line),
material: Cesium.Color.RED,
fill: false, //不显示填充
outline: true,
outlineWidth: 5.0,
outlineColor: Cesium.Color.RED
},
label: {
text: polygonDis.toString(),
font: '20px SimHei ',
Width: 10,
style: Cesium.LabelStyle.FILL_AND_OUTLINE,
fillColor: Cesium.Color.YELLOW,
outlineColor : Cesium.Color.GRAY,
outlineWidth :5,
horizontalOrigin: Cesium.HorizontalOrigin.CENTER,
verticalOrigin: Cesium.VerticalOrigin.BOTTOM
},
/* label : {
// This callback updates the length to print each frame.
text: polygonDis.toString(),
font : '25px',
pixelOffset : new Cesium.Cartesian2(1, 1)
},*/
position: Cesium.Cartesian3.fromDegrees(firstPointLon, firstPointLat)
});
}
PolygonPointArray_line = null;
viewer.entities.getById("moveLine_first").polyline.show = false;
viewer.entities.getById("moveLine_second").polyline.show = false;
}
isStartDraw = false;
}
}
}, Cesium.ScreenSpaceEventType.LEFT_DOUBLE_CLICK);
}
//加多边形不带填充
function measureArea() {
var select_measure = document.getElementById("selOpt");
var value_measure = select_measure.options[select_measure.selectedIndex].value;
if(value_measure == 2){
isPoint = false;
isPolyline = false;
isPolygon_line = true;
isPolygon_fill = false;
isStartDraw = false;
QQ=0;
document.body.style.cursor = "url(resource/pic/icons/magnifier3.cur) 12 12,crosshair";
document.getElementById("map_container").style.cursor = "url(resource/pic/icons/magnifier3.cur) 12 12,crosshair";
addOnClickListener();
}
}唔，大概主要功能就是这些了。给自己备忘，代码包我就不传了，如果有问题或者想了解更多的童鞋可以私信或者微我 ^V^
Life is like a box of chocolate，you never know what you're gonna get next.
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