sdk4.0/src/Measure/MeasureTdArea/index.js

import Measure from "../index"

/**@extends Measure*/
class MeasureTdArea extends Measure {
  /**
   * @constructor
   * @param sdk 
   * @description 贴地面积测量
   * */
  constructor(sdk, options = {}) {
    super(sdk, options);
    this.options.lineColor = '#ffdf53'
    this.polygon_id = ""
  }

  static create_polygon(that) {
    let id = that.randomString()

    let scaleByDistance = new Cesium.NearFarScalar(2000, 1, 100000, 0)

    let e = that.viewer.entities.add(
      new Cesium.Entity({
        id: id,
        label: {
          text: new Cesium.CallbackProperty(() => {
            return that.text
          }, false),
          //标注文字描述
          font: '20px Microsoft YaHei',
          fillColor: Cesium.Color.fromCssColorString('#ffffff'),
          style: Cesium.LabelStyle.FILL_AND_OUTLINE,
          //标注的遮挡距离设置为100则视角与标注的距离大于100米时会有遮挡
          // distanceDisplayCondition: this.distanceDisplayCondition,

          disableDepthTestDistance: Number.POSITIVE_INFINITY,

          // scaleByDistance,
          scale: 1,
          horizontalOrigin: Cesium.HorizontalOrigin.CENTER,
          verticalOrigin: Cesium.VerticalOrigin.BOTTOM,
        },
        position: new Cesium.CallbackProperty(() => {
          return that.center
        }, false),
        polygon: {
          classificationType: Cesium.ClassificationType.BOTH,
          hierarchy: new Cesium.CallbackProperty((e) => {
            return new Cesium.PolygonHierarchy(that.positions)
          }, false),
          material: new Cesium.Color.fromCssColorString(that.options.color || that.defaultColor),
          zIndex: 99999999
        },
        polyline: {
          positions: new Cesium.CallbackProperty(() => {
            if (that.positions.length)
              return that.positions.concat(that.positions[0])
            return that.positions
          }, false),
          width: 2,
          material: new Cesium.PolylineDashMaterialProperty({
            color: new Cesium.Color.fromCssColorString(that.options.lineColor || that.defaultColor),
            dashLength: 20, //短划线长度
          }),
          clampToGround: true,
          zIndex: 99999999
        }
      })
    )
    return id
  }

  /**
   * 开始测量
   */
  start() {
    if (!YJ.Measure.GetMeasureStatus()) {
      super.start()
      this.ids = []
      this.positions = []
      this.text = ""
      this.center = new Cesium.Cartesian3()
      this.cachePositions = []
      let height = 0
      let text

      let leftEvent = (movement, car) => {
        if (this.ids.length === 0) {
          this.polygon_id = MeasureTdArea.create_polygon(this)
        }
        this.cachePositions.push({ ...car })
        this.ids.push(this.create_point({ ...car }, false))
        let po = this.cartesian3Towgs84({ ...car }, this.viewer)
        if (po.alt > height) {
          height = po.alt
        }

        this.positions = this.cachePositions.concat({ ...car })
        this.tip.setPosition({ ...car }, movement.position.x, movement.position.y)
      }
      let rightEvent = (movement, car) => {
        this.positions = this.cachePositions
        if (this.positions.length > 2) {
          let arr = []
          this.positions.forEach(item => {
            let p = this.cartesian3Towgs84(item, this.viewer)
            arr.push({ lng: p.lng, lat: p.lat })
          })
          setTimeout(() => {
            let center = this.computeCenter(arr)
            let area = this.computeSignedArea(this.viewer, arr)
            this.center = new Cesium.Cartesian3.fromDegrees(center.lng, center.lat, height)
            this.text = "贴地面积：" + area + " ㎡"
          }, 0);
        }
        else {
          let error = '面积计算至少需要三个坐标！'
          console.warn(error)
          window.ELEMENT && window.ELEMENT.Message({
            message: error,
            type: 'warning',
            duration: 1500
          });
          this.destroy()
        }
        this.end()
      }
      this.event.mouse_left(leftEvent)
      this.event.mouse_move((movement, car) => {
        this.tip.setPosition({ ...car }, movement.endPosition.x, movement.endPosition.y)
        this.positions = this.cachePositions.concat({ ...car })
      })
      this.event.mouse_right(rightEvent)
      this.event.gesture_pinck_start((movement, cartesian) => {
        let startTime = new Date()
        let pos = {
          position: {
            x: (movement.position1.x + movement.position2.x) / 2,
            y: (movement.position1.y + movement.position2.y) / 2
          }
        }
        this.event.gesture_pinck_end(() => {
          let endTime = new Date()
          if (endTime - startTime >= 500) {
            // 长按取消
            rightEvent(pos, cartesian)
          }
          else {
            leftEvent(pos, cartesian)
          }
        })
      })
    }
  }

  /**
   * 清除测量
   */
  destroy() {
    [this.polygon_id, ...this.ids].forEach(id => {
      this.remove_entity(id)
    })
    super.destroy()
  }

  /**
   * 结束测量
   */
  end() {
    super.end()
  }
}

export default MeasureTdArea