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Public Sub getPlEachPartInfo(ByRef objPL As AcadLWPolyline, dblDistArr() As Double, dblMidPt() As Double, dblMidPt_NormalVector() As Double, dbl_Bugle_Radius() As Double)
'取得多线段本身不提供的各段属性
On Error GoTo ToExit '打开错误陷阱
'------------------------------------------------
'dblDistArr 各段距离
'dblMidPt 各段中点
'dblMidPt_NormalVector 各段中点法向量角度
'dbl_Bugle_Radius 各段bugle的半径
If objPL Is Nothing Then Exit Sub
Dim i As Long
Dim k As Double '斜率
Dim dblA As Double, dblB As Double, dblC As Double '直线方程三系数
Dim dblP1(2) As Double, dblP2(2) As Double, B_0_flag As Boolean '直线两点，及b=0标志
Dim dblChordAs Double, dblSagitta As Double '弦长，拱高
Dim dblMidPt_tmp As Variant, dblMidPt_tmp2(2) As Double '临时用中点
Dim dblAngle_tmp As Double'临时用角度
ReDim dblDistArr((UBound(objPL.Coordinates) - LBound(objPL.Coordinates) + 1) \ 2 - 2)
ReDim dblMidPt(UBound(objPL.Coordinates) - 2)
ReDim dblMidPt_NormalVector((UBound(objPL.Coordinates) - LBound(objPL.Coordinates) + 1) \ 2 - 2)
ReDim dbl_Bugle_Radius((UBound(objPL.Coordinates) - LBound(objPL.Coordinates) + 1) \ 2 - 2)
Dim objDoc As AcadDocument
Set objDoc = ThisDrawing()
For i = 0 To UBound(dblDistArr)
dblP1(0) = objPL.Coordinates(2 * i)
dblP1(1) = objPL.Coordinates(2 * i + 1)
dblP2(0) = objPL.Coordinates(2 * i + 2)
dblP2(1) = objPL.Coordinates(2 * i + 3)
If objPL.GetBulge(i) = 0 Then
dblDistArr(i) = GetDist2D(dblP1(0), dblP1(1), dblP2(0), dblP2(1))
dblMidPt(2 * i) = (dblP1(0) + dblP2(0)) / 2
dblMidPt(2 * i + 1) = (dblP1(1) + dblP2(1)) / 2
dblAngle_tmp = objDoc.Utility.AngleFromXAxis(dblP1, dblP2)
dblMidPt_NormalVector(i) = PI / 2 + dblAngle_tmp
dbl_Bugle_Radius(i) = 0
ElseIf objPL.GetBulge(i) <> 0 Then
dblChord = GetDist2D(dblP1(0), dblP1(1), dblP2(0), dblP2(1)) '求出弦长
dblSagitta = Abs(dblChord / 2 * objPL.GetBulge(i)) '求出拱高
dbl_Bugle_Radius(i) = (dblSagitta ^ 2 + (dblChord / 2) ^ 2) / dblSagitta / 2 '求出半径
dblAngle_tmp = objDoc.Utility.AngleFromXAxis(dblP1, dblP2)
dblMidPt_NormalVector(i) = -Sgn(objPL.GetBulge(i)) * PI / 2 + dblAngle_tmp '始终在圆弧外面
dblMidPt_tmp2(0) = (dblP1(0) + dblP2(0)) / 2
dblMidPt_tmp2(1) = (dblP1(1) + dblP2(1)) / 2
dblMidPt_tmp = objDoc.Utility.PolarPoint(dblMidPt_tmp2, dblMidPt_NormalVector(i), dblSagitta)
dblMidPt(2 * i) = dblMidPt_tmp(0)
dblMidPt(2 * i + 1) = dblMidPt_tmp(1)
'''''
dblDistArr(i) = dbl_Bugle_Radius(i) * Abs(Atn(objPL.GetBulge(i))) * 4
End If
Next i
'------------------------------------------------
Exit Sub
'----------------
ToExit:
Resume Next
End Sub