有凸度的多段线问题

pynet

nArrow是半径还是弦心距呀？

能不能把getArrow子函数贴出来呀？

谢谢楼主～

lysgyx

我是用.net写的

是这样算的 

Function GetCenterFromBulge(ByVal Ps() As Double, ByVal Pe() As Double, ByVal Bulge As Double) As Double()
        '***************************************************
        '*     通过圆弧的端点和凸度值解算圆心坐标          *
        '***************************************************
        Dim DirSE As Double, DistSE As Double, DirC As Double
        Dim Radius As Double, Dv As Double, ArcLength As Double
        Dim Angle1 As Double, Angle2 As Double
        Dim P1(2) As Double, P(2) As Double
        If Bulge = 0 Then
            P(0) = 0
            P(1) = 0
            P(2) = 0
            Return P
        Else
            DirSE = Ftn(Pe(0) - Ps(0), Pe(1) - Ps(1))   '解求弦方位
            DistSE = Dist(Pe(0) - Ps(0), Pe(1) - Ps(1))   '解求弦长
            Dv = Bulge * DistSE / 2      '解求弦高
            Radius = Abs(DistSE ^ 2 / Dv / 8 + Dv / 2)  '解求圆半径
            Angle1 = Atan(Bulge)
            Angle2 = PI / 2 - Abs(Angle1) - Abs(Angle1)
            DirC = DirSE + Sign(Bulge) * Angle2
            P(0) = Ps(0) + Radius * Cos(DirC)
            P(1) = Ps(1) + Radius * Sin(DirC)
            P(2) = 0
            Return P
        End If
    End Function

zhang小小

学习了

liub951030

请大侠把代码贴全好吗，这样像我这样的菜鸟也用一下！

3xxx

用炸开法最简单。
Sub addarc2d() '起点和终点加凸度法画圆
Dim usarc As AcadArc
Dim pt1 As Variant
Dim pt2 As Variant
Dim pt3 As Variant
Dim points(0 To 3) As Double

pt1 = ThisDrawing.Utility.GetPoint(, "请输入圆弧起点:")
pt2 = ThisDrawing.Utility.GetPoint(pt1, "请输入圆弧终点:")
pt3 = ThisDrawing.Utility.GetReal("请输入圆弧角度:")
points(0) = pt1(0): points(1) = pt1(1)
points(2) = pt2(0): points(3) = pt2(1)
    Set plineobj = ThisDrawing.ModelSpace.AddLightWeightPolyline(points)
'    ZoomAll
'pt3 = pt3 * 3.1415926535 / 180
'pt3 = Tan(pt3)
    plineobj.SetBulge 0, Tan(0.25 * pt3 * 3.1415926535 / 180) '
    plineobj.Update
    Dim explodedObjects As Variant
    explodedObjects = plineobj.Explode
    Dim center(0 To 2) As Double
    'Dim centerPoint As Variant
    centerPoint = explodedObjects(0).center
    StartA = explodedObjects(0).StartAngle * (180 / 3.14)
    EndA = explodedObjects(0).EndAngle * (180 / 3.14)

End Sub

xchj81

有难度。学习学习[em0]