Class MathUtils

constructor

• new MathUtils(): MathUtils

• Returns MathUtils

Static getCircleCenterOfThreePoints

Static getRightMostControlPoint

Static computeEllipseAxes

• computeEllipseAxes(center, pnt2): {
      semiMajorAxis: number;
      semiMinorAxis: number;
  }

• Parameters

  • center: ProjectionPoint
  • pnt2: ProjectionPoint

  Returns {
      semiMajorAxis: number;
      semiMinorAxis: number;
  }

  • semiMajorAxis: number

  • semiMinorAxis: number

Static computePointInPolygon

• computePointInPolygon(point, polygon): boolean

• 判断点是否在多边形内部

  Parameters

  • point: ProjectionPoint

    要检测的点 [x, y]
  • polygon: ProjectionPoint[]

    多边形顶点集合 [[x1, y1], [x2, y2], ...]

  Returns boolean

  boolean 如果点在多边形内返回true，否则返回false

Static computePolygonArea

• computePolygonArea(points): number

• Parameters

  • points: ProjectionPoint[]

  Returns number

Static computeQuadraticBSplineFactor

• computeQuadraticBSplineFactor(t, o): number

• @descripttion: 计算二次B样条曲线插值中的特定因子

  Parameters

  • t: number
  • o: number

  Returns number

  @author: Xiaohu.Shen

Static computeQuadraticBSplinePoints

• computeQuadraticBSplinePoints(points): ProjectionPoint[]

• 计算二次B样条曲线点集

  Parameters

  • points: ProjectionPoint[]

    控制点数组，每个元素是[x,y]坐标

  Returns ProjectionPoint[]

  返回平滑后的B样条曲线点集

Static getAngleOfThreePoints

• getAngleOfThreePoints(left, origin, right): number

• @descripttion: 根据三个点计算夹角

  Parameters

  • left: ProjectionPoint
  • origin: ProjectionPoint
  • right: ProjectionPoint

  Returns number

  @author: Xiaohu.Shen

Static getArcPoints

• getArcPoints(center, radius, startAngle, endAngle, clockwise?): ProjectionPoint[]

• @descripttion: 计算弧线段的点集

  Parameters

  • center: ProjectionPoint
  • radius: number
  • startAngle: number
  • endAngle: number
  • Optional clockwise: boolean

  Returns ProjectionPoint[]

Static getAzimuth

• getAzimuth(origin, target): number

• @descripttion: 获取方位角（地平经度，弧度制）

  Parameters

  • origin: ProjectionPoint
  • target: ProjectionPoint

  Returns number

  @author: Xiaohu.Shen

Static getBinomialFactor

• getBinomialFactor(x, y): number

• @descripttion: 二项式分布

  Parameters

  • x: number
  • y: number

  Returns number

  @author: Xiaohu.Shen

Static getBisectorNormals

• getBisectorNormals(t, pnt1, pnt2, pnt3): ProjectionPoint[]

• @descripttion: 计算经过三个点的外接圆在中间点处的切线方向的左右两个法向量

  Parameters

  • t: number

    控制切线法向量长度的缩放因子，值越大法向量点离中间点越远
  • pnt1: ProjectionPoint

    第一个点
  • pnt2: ProjectionPoint

    中间点
  • pnt3: ProjectionPoint

    第二个点

  Returns ProjectionPoint[]

  [右法向量, 左法向量] @author: Xiaohu.Shen

Static getCircleTangentNormalAtPoint2

• getCircleTangentNormalAtPoint2(pnt1, pnt2, pnt3): ProjectionPoint

• @descripttion: 计算经过三个点 pnt1、pnt2 和 pnt3 的外接圆在 pnt2 处的切线方向的法向量

  Parameters

  • pnt1: ProjectionPoint
  • pnt2: ProjectionPoint
  • pnt3: ProjectionPoint

  Returns ProjectionPoint

  法向量 @author: Xiaohu.Shen

Static getCubicBezierPoints

• getCubicBezierPoints(points, numberOfPoints?): ProjectionPoint[]

• @descripttion: 三次贝塞尔插值

  Parameters

  • points: ProjectionPoint[]

    轨迹关键点
  • Optional numberOfPoints: number

    插值点数

  Returns ProjectionPoint[]

  @author: Xiaohu.Shen

Static getCurvePoints

• getCurvePoints(t, controlPoints): ProjectionPoint[]

• @descripttion: 计算一条经过控制点集的曲线上的点

  Parameters

  • t: number
  • controlPoints: ProjectionPoint[]

  Returns ProjectionPoint[]

  @author: Xiaohu.Shen

Static getFactorial

• getFactorial(origin): number

• @descripttion: 阶乘

  Parameters

  • origin: number

  Returns number

  @author: Xiaohu.Shen

Static getHeading

• getHeading(posA, posB): number

• @descripttion: 计算两点间偏航角

  Parameters

  • posA: Geographic

    A点坐标
  • posB: Geographic

    B点坐标

  Returns number

  @author: Xiaohu.Shen

Static getIntersectPoint

• getIntersectPoint(lineA, lineB): Point

• @descripttion: 计算两条线的交点

  Parameters

  • lineA: [Point, Point]
  • lineB: [Point, Point]

  Returns Point

  交点 @author: Xiaohu.Shen

Static getLeftMostControlPoint

• getLeftMostControlPoint(controlPoints, t): ProjectionPoint

• @descripttion: 获取曲线控制点集起始坐标的左侧

  Parameters

  • controlPoints: ProjectionPoint[]
  • t: number

  Returns ProjectionPoint

  @author: Xiaohu.Shen

Static getPointOnCubicBezier

• getPointOnCubicBezier(t, startPnt, cPnt1, cPnt2, endPnt): ProjectionPoint

• @descripttion: 计算三次贝塞尔曲线上的点

  Parameters

  • t: number
  • startPnt: ProjectionPoint
  • cPnt1: ProjectionPoint
  • cPnt2: ProjectionPoint
  • endPnt: ProjectionPoint

  Returns ProjectionPoint

  @author: Xiaohu.Shen

Static getPointOnLine

• getPointOnLine(t, startPnt, endPnt): Point

• 获取线上的点

  Parameters

  • t: number
  • startPnt: Point
  • endPnt: Point

  Returns Point

Static getQuadricBezierPoints

• getQuadricBezierPoints(points): ProjectionPoint[]

• @descripttion: 二次贝塞尔插值

  Parameters

  • points: ProjectionPoint[]

  Returns ProjectionPoint[]

  @author: Xiaohu.Shen

Static getSymmetricalPoint

• getSymmetricalPoint(basicPnt1, basicPnt2, originPnt): ProjectionPoint

• @descripttion: 获取对称点

  Parameters

  • basicPnt1: ProjectionPoint
  • basicPnt2: ProjectionPoint
  • originPnt: ProjectionPoint

  Returns ProjectionPoint

  @author: Xiaohu.Shen

Static getThirdPoint

• getThirdPoint(origin, target, radians, distance, clockwise): ProjectionPoint

• @descripttion: 根据起止点和旋转方向求取第三个点（在目标点基础上进行旋转）

  Parameters

  • origin: ProjectionPoint

    源点
  • target: ProjectionPoint

    目标点
  • radians: number

    旋转弧度
  • distance: number

    距离
  • clockwise: boolean

    顺时针

  Returns ProjectionPoint

  @author: Xiaohu.Shen

Static getVector

• getVector(left, right): Cartesian3

• @descripttion: 计算两点间向量（三维）

  Parameters

  • left: Cartesian3

    左边点
  • right: Cartesian3

    右边点

  Returns Cartesian3

  单位向量 @author: Xiaohu.Shen

Static isPathClockwise

• isPathClockwise(pointA, pointB, pointC): boolean

• @description: 判断三点组成的路径方向是否为顺时针（A->B->C）

  Parameters

  • pointA: ProjectionPoint

    路径起点
  • pointB: ProjectionPoint

    路径中间点
  • pointC: ProjectionPoint

    路径终点

  Returns boolean

  true 表示顺时针，false 表示逆时针或共线 @author: Xiaohu.Shen

Static isPositiveNumber

• isPositiveNumber(value, includeZero?): boolean

• Parameters

  • value: number
  • Optional includeZero: boolean

  Returns boolean

Static mid

• mid(t, o): Point

• @descripttion: 计算中点

  Parameters

  • t: Point
  • o: Point

  Returns Point

  @author: Xiaohu.Shen

Static projectionDistance

• projectionDistance(target, origin): number

• @descripttion: 两点间的投影距离（二维）

  Parameters

  • target: ProjectionPoint
  • origin: ProjectionPoint

  Returns number

  @author: Xiaohu.Shen

Static randomWithRange

• randomWithRange(min, max, isInt?): number

• @descripttion: 根据边界获取随机数

  Parameters

  • min: number

    最小值
  • max: number

    最大值
  • Optional isInt: boolean

    是否整型(默认true)

  Returns number

  @author: Xiaohu.Shen

Static secondsToHMS

• secondsToHMS(value, withDay?): {
      H: string | number;
      M: string | number;
      S: string | number;
  }

• Parameters

  • value: number
  • Optional withDay: boolean

  Returns {
      H: string | number;
      M: string | number;
      S: string | number;
  }

  • H: string | number

  • M: string | number

  • S: string | number

Static secondsToHMSInCHN

• secondsToHMSInCHN(value, withDay?): string

• Parameters

  • value: number
  • Optional withDay: boolean

  Returns string

Static secondsToHMSInStr

• secondsToHMSInStr(value, withDay?): string

• Parameters

  • value: number
  • Optional withDay: boolean

  Returns string

Static toDMS

• toDMS(degree): {
      degree: number;
      minute: number;
      second: number;
  }

• @descripttion: 度转度°分′秒″

  Parameters

  • degree: number

    角度（-180-180）

  Returns {
      degree: number;
      minute: number;
      second: number;
  }

  @author: Xiaohu.Shen

  • degree: number

  • minute: number

  • second: number

Static toDegree

• toDegree(degree, minute, second, precision?): number

• @descripttion: 度°分′秒″转度

  Parameters

  • degree: number

    度（0-180）
  • minute: number

    分（0-60）
  • second: number

    秒（0-60）
  • Optional precision: number

    数值精度（默认为最高精度6）

  Returns number

  @author: Xiaohu.Shen

Static wholeProjectionDistance

• wholeProjectionDistance(path): number

• @descripttion: 各点间的距离累计和（二维）

  Parameters

  • path: Point[]

  Returns number

  @author: Xiaohu.Shen