使用new mars3d.graphic.PolylinePrimitive({的时候报错 At least two positions are required.

问题：

1.使用new mars3d.graphic.PolylinePrimitive({的时候报错 At least two positions are required.

解决：

1.提示十分明确：坐标数量少于2个无法渲染线

此时参考mars3d官网的示例，传入指定数据在按需修改即可。

效果：

相关代码：

function addDemoGraphic1(graphicLayer) {

const graphic = new mars3d.graphic.PolylinePrimitive({

positions: [

[117.220337, 31.832987],

[117.220242, 31.835234],

[117.216263, 31.835251],

[117.217219, 31.819929],

[117.223096, 31.818342],

[117.249686, 31.818964],

[117.263171, 31.816664],

[117.278695, 31.816107],

[117.279826, 31.804185],

[117.286308, 31.804112],

[117.28621, 31.801059]

style: {

width: 4,

materialType: mars3d.MaterialType.LineTrail,

materialOptions: {

color: Cesium.Color.CHARTREUSE,

speed: 5

clampToGround: true,

label: {

text: "我是线",

font_size: 18,

color: "#ffffff",

distanceDisplayCondition: true,

distanceDisplayCondition_far: 500000,

distanceDisplayCondition_near: 0

}

attr: { remark: "示例1" }

})

graphicLayer.addGraphic(graphic)

}

官网链接：

功能示例(Vue版) | Mars3D三维可视化平台 | 火星科技