选定线的最近端点

Public Sub testGetClosestEndpoint()
    Dim oEnt As AcadEntity
    Dim vPickedPoint As Variant
    Dim vPoint As Variant
    Dim vResult As Variant
    
    ThisDrawing.Utility.GetEntity oEnt, vPickedPoint, "Pick (p)Line: "
   
    vResult = GetClosestEndPt(oEnt, vPickedPoint, False)
    Debug.Print vResult(0), vResult(1), vResult(2)
End Sub
Public Function GetClosestEndPt(pLineEnt As AcadEntity, pPoint As Variant, p3dIfTrue As Boolean) As Variant
    Dim vTemp1 As Variant
    Dim oLine As AcadLine
    Dim oLwPline As AcadLWPolyline
    Dim oPline As AcadPolyline
    Dim o3dPline As Acad3DPolyline
    Dim maxVert As Integer
    
    Dim dist1 As Double
    Dim dist2 As Double
    Dim retVal As Variant
    
    If TypeOf pLineEnt Is AcadLine Then
        Set oLine = pLineEnt
        dist1 = CalcDist(oLine.StartPoint, pPoint, p3dIfTrue)
        dist2 = CalcDist(oLine.EndPoint, pPoint, p3dIfTrue)
        If dist1 <= dist2 Then
            retVal = oLine.StartPoint
        Else
            retVal = oLine.EndPoint
        End If
    ElseIf TypeOf pLineEnt Is AcadLWPolyline Then
        Set oLwPline = pLineEnt
        maxVert = (UBound(oLwPline.Coordinates) - 1) / 2
        dist1 = CalcDist(oLwPline.Coordinate(0), pPoint, p3dIfTrue)
        dist2 = CalcDist(oLwPline.Coordinate(maxVert), pPoint, p3dIfTrue)
        If dist1 <= dist2 Then
            retVal = oLwPline.Coordinate(0)
        Else
            retVal = oLwPline.Coordinate(maxVert)
        End If
    ElseIf TypeOf pLineEnt Is AcadPolyline Then
        Set oPline = pLineEnt
        maxVert = (UBound(oPline.Coordinates) - 2) / 3
        dist1 = CalcDist(oPline.Coordinate(0), pPoint, p3dIfTrue)
        dist2 = CalcDist(oPline.Coordinate(maxVert), pPoint, p3dIfTrue)
        If dist1 <= dist2 Then
            retVal = oPline.Coordinate(0)
        Else
            retVal = oPline.Coordinate(maxVert)
        End If
    ElseIf TypeOf pLineEnt Is Acad3DPolyline Then
        Set o3dPline = pLineEnt
        maxVert = (UBound(o3dPline.Coordinates) - 2) / 3
        dist1 = CalcDist(o3dPline.Coordinate(0), pPoint, p3dIfTrue)
        dist2 = CalcDist(o3dPline.Coordinate(maxVert), pPoint, p3dIfTrue)
        If dist1 <= dist2 Then
            retVal = o3dPline.Coordinate(0)
        Else
            retVal = o3dPline.Coordinate(maxVert)
        End If
    End If
    
    GetClosestEndPt = retVal
    
    
End Function
Public Function CalcDist(pPt1 As Variant, pPt2 As Variant, p3dIfTrue As Boolean) As Double
    Dim temp As Double
    
    If p3dIfTrue Then
        temp = Sqr((pPt1(0) - pPt2(0)) ^ 2 + (pPt1(1) - pPt2(1)) ^ 2 + (pPt1(2) - pPt2(2)) ^ 2)
    Else
       temp = Sqr((pPt1(0) - pPt2(0)) ^ 2 + (pPt1(1) - pPt2(1)) ^ 2)
    End If
    
    CalcDist = temp
End Function