vue3如何使用cesium实现钳式箭头

要使用Vue3和Cesium实现钳式箭头，可以按照以下步骤进行：

1. 在Vue项目中安装Cesium，并在组件中引入Cesium

npm install cesium --save

import * as Cesium from 'cesium/Cesium'

2. 在组件中创建Cesium Viewer，并设置其容器和其他属性

this.viewer = new Cesium.Viewer(this.$refs.cesiumContainer, {
  animation: false,
  baseLayerPicker: false,
  fullscreenButton: false,
  geocoder: false,
  homeButton: false,
  infoBox: false,
  sceneModePicker: false,
  selectionIndicator: false,
  timeline: false,
  navigationHelpButton: false,
  navigationInstructionsInitiallyVisible: false,
  scene3DOnly: true
})

3. 创建钳式箭头的函数，该函数接受起点、终点和钳式箭头的长度和宽度作为参数，并返回一个Cesium Entity

function createClawArrow(start, end, length, width) {
  // 创建一个直线Entity
  var lineEntity = viewer.entities.add({
    polyline: {
      positions: [start, end],
      width: 2,
      material: Cesium.Color.RED
    }
  })

  // 计算箭头的方向向量
  var direction = Cesium.Cartesian3.subtract(end, start, new Cesium.Cartesian3())
  Cesium.Cartesian3.normalize(direction, direction)

  // 计算箭头的两个钳子的向量
  var left = new Cesium.Cartesian3(-direction.y, direction.x, 0)
  var right = new Cesium.Cartesian3(direction.y, -direction.x, 0)

  // 计算钳子的起点和终点
  var leftStart = Cesium.Cartesian3.add(end, Cesium.Cartesian3.multiplyByScalar(left, length, new Cesium.Cartesian3()), new Cesium.Cartesian3())
  var leftEnd = Cesium.Cartesian3.add(end, Cesium.Cartesian3.multiplyByScalar(left, width, new Cesium.Cartesian3()), new Cesium.Cartesian3())
  var rightStart = Cesium.Cartesian3.add(end, Cesium.Cartesian3.multiplyByScalar(right, length, new Cesium.Cartesian3()), new Cesium.Cartesian3())
  var rightEnd = Cesium.Cartesian3.add(end, Cesium.Cartesian3.multiplyByScalar(right, width, new Cesium.Cartesian3()), new Cesium.Cartesian3())

  // 创建箭头的两个钳子
  var leftEntity = viewer.entities.add({
    polyline: {
      positions: [leftStart, leftEnd],
      width: 2,
      material: Cesium.Color.RED
    }
  })

  var rightEntity = viewer.entities.add({
    polyline: {
      positions: [rightStart, rightEnd],
      width: 2,
      material: Cesium.Color.RED
    }
  })

  // 返回箭头的Entity
  return new Cesium.Entity({
    name: 'Claw Arrow',
    show: true,
    polyline: {
      positions: [start, end],
      width: 2,
      material: Cesium.Color.RED
    },
    children: [leftEntity, rightEntity]
  })
}

4. 在组件中调用createClawArrow函数，并将返回的Entity添加到Cesium Viewer中

var start = Cesium.Cartesian3.fromDegrees(-75.59777, 40.03883, 0)
var end = Cesium.Cartesian3.fromDegrees(-75.58777, 40.04883, 0)
var length = 100
var width = 50
var clawArrow = createClawArrow(start, end, length, width)
viewer.entities.add(clawArrow)

这样就可以在Cesium Viewer中显示钳式箭头了。