Cesium剖面分析（获取剖面高程示意图）
1，实现效果如下图所示：
,2，关键代码（获取点击处的高程信息）：
var handler = new Cesium.ScreenSpaceEventHandler(viewer.scene.canvas);
handler.setInputAction(function (event) {
var ray = myApp.baseMap.obj.camera.getPickRay(event.position);
var position = viewer.scene.globe.pick(ray, viewer.scene);
if (Cesium.defined(position)) {
var cartographic = Cesium.Ellipsoid.WGS84.cartesianToCartographic(position);
alert("点击处海拔高度为：" + cartographic.height +"米");
} else {
}
}, Cesium.ScreenSpaceEventType.LEFT_CLICK);3，实现思路：
使用一条线段来进行剖面分析，将线段等分成10个点。使用上面的代码获取每个点的高程信息，将每个点的高程连成一条直线，就能够获得上面的剖面分析示意图了（使用echarts就行可视化）。
线段等分代码实现：
var pointSum = 10; //取样点个数
var addXTT = Cesium.Math.lerp(startX, endX, 1.0/pointSum) - startX;
var addYTT = Cesium.Math.lerp(startY, endY, 1.0/pointSum) - startY;4，零散代码
这部分代码可以不看，通过上面的分析，你完全可以自己进行实现了。可以从这段代码了获得一些你想要的东西。
define(['Cesium','SuperMap','js/analysis/Convert','echartsMin','js/polygonStatistics/tooltip'],function(Cesium, Super, Convert,echarts,tooltip) {
'use strict';
var $ = require('jquery');
/*
* 剖面分析对象
* 画线截取剖面
* 起点信息和终点信息
* 分析结果小窗口显示
*
* */
var handlerLine;
var line;
var profile = function () {
};
var crossProfile;
var htmlStr =
'' +
'
' +
'' +
''+
'';
profile.remove = function(){
$('#profileLong1').val(0.0);
$('#profileLat1').val(0.0);
$('#profileAlt1').val(0.0);
$('#profileLong2').val(0.0);
$('#profileLat2').val(0.0);
$('#profileAlt2').val(0.0);
if(handlerLine){
handlerLine.clear();
}
$("#sceneAttribute").hide();
$("#pro").width(0);
$("#pro").height(0);
if(crossProfile){
crossProfile.destroy();
crossProfile = undefined;
}
};
profile.initializing = function(viewer){
$("#sceneAttribute").empty().append(htmlStr);
$("#sceneAttribute").hide();
$("#closeScene").bind("click",function () {
$("#sceneAttribute").hide();
if(handlerLine){
handlerLine.clear();
}
})
var scene = viewer.scene;
var tooltip = createTooltip(document.body);
if(!crossProfile){
crossProfile = new Cesium.Profile(scene);
}
if(handlerLine){
handlerLine.clear();
}
handlerLine = new Cesium.DrawHandler(viewer,Cesium.DrawMode.Line);
var handler = new Cesium.ScreenSpaceEventHandler(scene.canvas);
handlerLine.activeEvt.addEventListener(function(isActive){
if(isActive == true){
viewer.enableCursorStyle = false;
viewer._element.style.cursor = '';
$('body').removeClass('drawCur').addClass('drawCur');
}
else{
viewer.enableCursorStyle = true;
$('body').removeClass('drawCur');
}
});
handlerLine.movingEvt.addEventListener(function(windowPosition){
if(handlerLine.isDrawing){
console.log("第一个点绘制完成");
tooltip.showAt(windowPosition,'右键单击结束绘制
');
}
else{
tooltip.showAt(windowPosition,'点击绘制第一个点
');
}
});
var leftX = 0;
var leftY = 0;
var rightX,rightY;
handler.setInputAction(function (leftEvent) {
leftX = leftEvent.position.x;
leftY = leftEvent.position.y;
handler.removeInputAction(Cesium.ScreenSpaceEventType.LEFT_CLICK);
handler.setInputAction(function (rightEvent) {
rightX = rightEvent.position.x;
rightY = rightEvent.position.y;
handler.removeInputAction(Cesium.ScreenSpaceEventType.RIGHT_CLICK);
}, Cesium.ScreenSpaceEventType.RIGHT_CLICK);
}, Cesium.ScreenSpaceEventType.LEFT_CLICK);
handlerLine.drawEvt.addEventListener(function(result) {
setTimeout(function () {
console.log("最后一个点绘制完成");
tooltip.setVisible(false);
line=result.object;
var startPoint = line._positions[0];
var endPoint = line._positions[line._positions.length - 1];
//起止点相关信息
var scartographic = Cesium.Cartographic.fromCartesian(startPoint);
var slongitude = Cesium.Math.toDegrees(scartographic.longitude);
var slatitude = Cesium.Math.toDegrees(scartographic.latitude);
var sheight = scartographic.height;
var ecartographic = Cesium.Cartographic.fromCartesian(endPoint);
var elongitude = Cesium.Math.toDegrees(ecartographic.longitude);
var elatitude = Cesium.Math.toDegrees(ecartographic.latitude);
var eheight = ecartographic.height;
$('#profileLong1').val(slongitude);
$('#profileLat1').val(slatitude);
$('#profileAlt1').val(sheight);
$('#profileLong2').val(elongitude);
$('#profileLat2').val(elatitude);
$('#profileAlt2').val(eheight);
$("#sceneAttribute").show();
var pointSum = 10; //取样点个数
var addXTT = Cesium.Math.lerp(slongitude, elongitude, 1.0/pointSum) - slongitude;
var addYTT = Cesium.Math.lerp(slatitude, elatitude, 1.0/pointSum) - slatitude;
var addX = Cesium.Math.lerp(leftX, rightX, 1.0/pointSum) - leftX;
var addY = Cesium.Math.lerp(leftY, rightY, 1.0/pointSum) - leftY;
var heightArr = [];
var dp1,dp2;
for(var i =0; i < pointSum; i++){
var longitude = slongitude + (i+1) * addXTT;
var latitude = slatitude + (i+1) * addYTT;
if (i == 0){
dp1 = new Cesium.Cartesian3(longitude, latitude, 0);
} else if (i == 1){
dp2 = new Cesium.Cartesian3(longitude, latitude, 0);
}
var x = leftX + (i+1) * addX;
var y = leftY + (i+1) * addY;
var eventPosition = {x:x,y:y};
var ray = viewer.camera.getPickRay(eventPosition);
var position = viewer.scene.globe.pick(ray, viewer.scene);
if (Cesium.defined(position)) {
var cartographic = Cesium.Ellipsoid.WGS84.cartesianToCartographic(position);
console.log("点击处海拔高度为：" + cartographic.height +"米");
heightArr[i] = cartographic.height.toFixed(2); //保留两位小数
}
}
//计算两个三维坐标之间的距离
var juli = Math.round(Cesium.Cartesian3.distance(dp1,dp2) * 100000); //dp1、dp2 都是三维坐标系
var yData = heightArr;
var xData = [];
for (var i = 0; i < pointSum;i++){
if(i == 0){
xData[i] = 0;
}else {
xData[i] = xData[i - 1] + juli;
}
}
var myChart = echarts.init(document.getElementById("pro"));
var option = {
title : {
text: '剖面示意图',
left: 'center',
subtext: '',
textStyle: {
color: 'white',
fontSize:15
}
},
tooltip : {
trigger: 'axis'
},
legend: {
data:['']
},
//右上角工具条
toolbox: {
show : false,
feature : {
mark : {show: true},
dataView : {show: true, readOnly: false},
magicType : {show: true, type: ['line', 'bar']},
restore : {show: true},
saveAsImage : {show: true}
}
},
calculable : true,
xAxis : [
{
type : 'category',
name:"长度(米)",
boundaryGap : false,
data : xData,
axisLabel : {
textStyle: {
color: 'white'
}
},
axisLine:{
lineStyle:{
color:"white"
}
}
}
],
yAxis : [
{
type : 'value',
name:"高程（米）",
axisLabel : {
// formatter: '{value} 米',
textStyle: {
color: 'white'
}
},
axisLine:{
lineStyle:{
color:"white"
}
}
}
],
series : [
{
name:'高程',
type:'line',
data:yData,
markPoint : {
data : [
{type : 'max', name: '最大值'},
{type : 'min', name: '最小值'}
]
},
markLine : {
data : [
{type : 'average', name: '平均值'}
]
}
}
]
};
// 为echarts对象加载数据
myChart.setOption(option);
},5);
});
handlerLine.activate();
$('#profileLong1').on('input propertychange',function(){
var cartesian = Cesium.Cartesian3.fromDegrees(parseFloat($('#profileLong1').val()), parseFloat($('#profileLat1').val()), parseFloat($('#profileAlt1').val()));
line._positions[0] = cartesian;
line._polylineCollection._polylines[0]._positions[0] = cartesian;
crossProfile.startPoint = [parseFloat($('#profileLong1').val()), parseFloat($('#profileLat1').val()), parseFloat($('#profileAlt1').val())];
})
$('#profileLat1').on('input propertychange',function(){
var cartesian = Cesium.Cartesian3.fromDegrees(parseFloat($('#profileLong1').val()), parseFloat($('#profileLat1').val()), parseFloat($('#profileAlt1').val()));
line._positions[0] = cartesian;
crossProfile.startPoint = [parseFloat($('#profileLong1').val()), parseFloat($('#profileLat1').val()), parseFloat($('#profileAlt1').val())];
})
$('#profileAlt1').on('input propertychange',function(){
var cartesian = Cesium.Cartesian3.fromDegrees(parseFloat($('#profileLong1').val()), parseFloat($('#profileLat1').val()), parseFloat($('#profileAlt1').val()));
line._positions[0] = cartesian;
crossProfile.startPoint = [parseFloat($('#profileLong1').val()), parseFloat($('#profileLat1').val()), parseFloat($('#profileAlt1').val())];
})
$('#profileLong2').on('input propertychange',function(){
var cartesian = Cesium.Cartesian3.fromDegrees(parseFloat($('#profileLong2').val()), parseFloat($('#profileLat2').val()), parseFloat($('#profileAlt2').val()));
line._positions[line._positions.length - 1] = cartesian;
crossProfile.endPoint = [parseFloat($('#profileLong2').val()), parseFloat($('#profileLat2').val()), parseFloat($('#profileAlt2').val())];
})
$('#profileLat2').on('input propertychange',function(){
var cartesian = Cesium.Cartesian3.fromDegrees(parseFloat($('#profileLong2').val()), parseFloat($('#profileLat2').val()), parseFloat($('#profileAlt2').val()));
line._positions[line._positions.length - 1] = cartesian;
crossProfile.endPoint = [parseFloat($('#profileLong2').val()), parseFloat($('#profileLat2').val()), parseFloat($('#profileAlt2').val())];
})
$('#profileAlt2').on('input propertychange',function(){
var cartesian = Cesium.Cartesian3.fromDegrees(parseFloat($('#profileLong2').val()), parseFloat($('#profileLat2').val()), parseFloat($('#profileAlt2').val()));
line._positions[line._positions.length - 1] = cartesian;
crossProfile.endPoint = [parseFloat($('#profileLong2').val()), parseFloat($('#profileLat2').val()), parseFloat($('#profileAlt2').val())];
})
$("#profileDel").bind("click",function () {
profile.remove();
})
}
return profile;
});