[VBA函数]：完美的三维螺旋线

ahlzl

在efan2000斑竹和各位网友的帮助下，终于完成了这段函数代码，因为我是新手，所以自我感觉特别好！觉得比明经的还好（脸皮真厚）！也许您能用的上。

Public Function AddHelix(pa As Variant, n As Integer, _
R1 As Double, R2 As Double, H As Double) As Acad3DPolyline
'pa是起点，n是匝数，R1是起点半径，R2是终点半径
'H是总高度
Dim polyObj As Acad3DPolyline
Dim points() As Double
Dim a As Integer
Const PI = 3.1415926535

pa = ThisDrawing.Utility.GetPoint(, "请输入基点：")
ReDim points(0 To 3 * 360 * n + 2) As Double

For a = 0 To 3 * 360 * n Step 3
points(a) = pa(0) + (R1 + (a / 3) * (R2 - R1) / 360 / n) _
* Cos(2 * PI * (a / 3) / 360)
points(a + 1) = pa(1) + (R1 + (a / 3) * (R2 - R1) / 360 / n) _
* Sin(2 * PI * (a / 3) / 360)
points(a + 2) = pa(2) + H * (a / 3) / 360 / n
Next

Set polyObj = ThisDrawing.ModelSpace.Add3DPoly(points)
ZoomExtents
End Function

螺旋线各点到中心轴的距离是严格按照线性关系变化的。下面是一段主程序调用示范。

Sub Example_Add3DPoly()
    Dim plineObj As Acad3DPolyline
    Set plineObj = AddHelix(pa, 10, 200, 100, 300)
End Sub

hxg_888

很好