第1个回答 2022-07-28
这个是我根据API及示例整理的历史轨迹播放的demo，其中重要的参数都做了注释，可以直接粘贴到cesium的模拟其中验证或做修改
//设定模拟时间的界限
var start = Cesium.JulianDate.fromDate(new Date(2021, 3, 2, 23,50,20));//朱利安时间=UTC=北京时间-8 2021-03-02 15：50：20
var stop = Cesium.JulianDate.fromDate(new Date(2021, 3, 2, 23,56,20));
//确保查看器在想要的时间
viewer.clock.startTime = start.clone();
viewer.clock.stopTime = stop.clone();
viewer.clock.currentTime = start.clone();
viewer.clock.clockRange = Cesium.ClockRange.CLAMPED; //达到终止时间后停止，LOOP_STOP：达到终止时间后重新循环，UNBOUNDED：达到终止时间后继续读秒
viewer.clock.multiplier = 10;//初始运行速度
//将时间轴设置为模拟边界
viewer.timeline.zoomTo(start, stop);
//生成一个一条线
function computeCirclularFlight() {
var property = new Cesium.SampledPositionProperty();
var dataSource = [{
'id':1,
'time':new Date(2021, 3, 2, 23,50,20),
'lng':120.43413519859315,
'lat':30.238649673375463,
},{
'id':2,
'time':new Date(2021, 3, 2, 23,51,20),
'lng':120.4343605041504,
'lat':30.23831135356134,
},{
'id':3,
'time':new Date(2021, 3, 2, 23,52,20),
'lng':120.43460726737977,
'lat':30.237908148974306,
},{
'id':4,
'time':new Date(2021, 3, 2, 23,53,20),
'lng':120.43478429317476,
'lat':30.237602268529127,
},{
'id':5,
'time':new Date(2021, 3, 2, 23,54,20),
'lng':120.4349720478058,
'lat':30.237282483409622,
},{
'id':6,
'time':new Date(2021, 3, 2, 23,55,20),
'lng':120.4351720478058,
'lat':30.236882483409622,
},{
'id':7,
'time':new Date(2021, 3, 2, 23,56,20),
'lng':120.4353720478058,
'lat':30.236482483409622,
}
];
for (var i = 0; i < 7; i ++) {
var time = Cesium.JulianDate.fromDate(dataSource[i].time);//每个点对应的时间
var position = Cesium.Cartesian3.fromDegrees(dataSource[i].lng,dataSource[i].lat,100);
property.addSample(time, position);
}
return property;
}
//Compute the entity position property.
var position = computeCirclularFlight();
//Actually create the entity
var entity = viewer.entities.add({
//Set the entity availability to the same interval as the simulation time.
availability: new Cesium.TimeIntervalCollection([
new Cesium.TimeInterval({
start: start,
stop: stop,
}),
]),
//Use our computed positions
position: position,
//Automatically compute orientation based on position movement.
orientation: new Cesium.VelocityOrientationProperty(position),
//Load the Cesium plane model to represent the entity
model: {
uri: "../SampleData/models/CesiumAir/Cesium_Air.glb",//模型地址
minimumPixelSize: 64,
},
//Show the path as a pink line sampled in 1 second increments.
path: {
resolution: 1,
material: new Cesium.PolylineGlowMaterialProperty({
glowPower: 0.1,
color: Cesium.Color.YELLOW,
}),
width: 10,
},
});
//添加按钮从顶部查看路径
Sandcastle.addDefaultToolbarButton("View Top Down", function () {
viewer.trackedEntity = undefined;
viewer.zoomTo(
viewer.entities,
new Cesium.HeadingPitchRange(0, Cesium.Math.toRadians(-90))
);
});
//添加按钮从侧面查看路径
Sandcastle.addToolbarButton("View Side", function () {
viewer.trackedEntity = undefined;
viewer.zoomTo(
viewer.entities,
new Cesium.HeadingPitchRange(
Cesium.Math.toRadians(-90),
Cesium.Math.toRadians(-15),
7500
)
);
});
//添加按钮来跟踪实体的移动
Sandcastle.addToolbarButton("View Aircraft", function () {
viewer.trackedEntity = entity;
});
//添加一个组合框来选择每个插值模式.
Sandcastle.addToolbarMenu(
[
{
text: "Interpolation: Linear Approximation",
onselect: function () {
entity.position.setInterpolationOptions({
interpolationDegree: 1,
interpolationAlgorithm: Cesium.LinearApproximation,
});
},
},
{
text: "Interpolation: Lagrange Polynomial Approximation",
onselect: function () {
entity.position.setInterpolationOptions({
interpolationDegree: 5,
interpolationAlgorithm:
Cesium.LagrangePolynomialApproximation,
});
},
},
{
text: "Interpolation: Hermite Polynomial Approximation",
onselect: function () {
entity.position.setInterpolationOptions({
interpolationDegree: 2,
interpolationAlgorithm: Cesium.HermitePolynomialApproximation,
});
},
},
],
"interpolationMenu"
);