Ellipse - Offseted as Ellipse, not as a spline.

[harilalmn]

Guys,
In AutoCAD if you offset an ellipse, the new object formed would be a spline, not an ellipse. I had a project in which I have to offset so many ellipses. It was too sad that I used to get splines instead of ellipse. So, I thought of writing a macro.

It is working perfectly and thought of sharing it. You will defenitely be able to have better suggestions after seeing the code, as I am not a master in VBA. Please feel free to feedback.

Here is the code.

Public Sub EllipseOffset()
On Error Resume Next
Dim El As AcadEllipse
Dim NEL As AcadEllipse
Dim C As Variant
Dim Center(0 To 2) As Double
Dim MjAx As Variant
Dim MiAx As Variant
Dim MajorAx(0 To 2) As Double
Dim MinorAx(0 To 2) As Double
Dim RadRatio As Double
Dim MajorRad, MinorRad As Double
Dim En As AcadEntity
Dim PkPnt As Variant
Dim Offset As Double
Dim InOut As String
Dim kwordList As String
Dim RepeatMacro As Boolean
Dim RepNum As Integer
Dim ConVal As Double
RepeatMacro = False
kwordList = "Inside Outside Multiple Repeat"
Repeat:
ThisDrawing.Utility.GetEntity En, Pk, "Select Ellipse:"
If Err Then Exit Sub
Offset = ThisDrawing.Utility.GetDistance(, "Offset:<" & ConVal & ">")
If Err Then Err.Clear
If Offset = 0 Then
Offset = 1
Else
ConVal = Round(Offset, 4)
End If
If Offset < 0 Then
Offset = Offset * -1
End If
    If TypeOf En Is AcadEllipse Then
        Set El = En
        C = El.Center
        Center(0) = C(0)
        Center(1) = C(1)
        Center(2) = C(2)
        MjAx = El.MajorAxis
        MiAx = El.MinorAxis
        MajorAx(0) = MjAx(0)
        MajorAx(1) = MjAx(1)
        MajorAx(2) = MjAx(2)
        MinorAx(0) = MiAx(0)
        MinorAx(1) = MiAx(1)
        MinorAx(2) = MiAx(2)
        MajorRad = El.MajorRadius
        MinorRad = El.MinorRadius
        RadRatio = El.RadiusRatio
Break:
        ThisDrawing.Utility.InitializeUserInput 1, kwordList
        If RepeatMacro = False Then
        InOut = ThisDrawing.Utility.GetKeyword("Enter an option (Inside,Outside,Multiple, Repeat): ")
        End If
        
        If RepeatMacro = True Then
        InOut = ThisDrawing.Utility.GetKeyword("Enter an option (Inside,Outside,Multiple): ")
        End If
        
        If InOut = "Repeat" Then
        kwordList = "Inside Outside Multiple"
        RepeatMacro = True
        GoTo Break
        End If
        
        If InOut = "Inside" Then
        Set NEL = ThisDrawing.ModelSpace.AddEllipse(Center, MajorAx, RadRatio)
        NEL.MajorRadius = MajorRad - Offset
        NEL.MinorRadius = MinorRad - Offset
        NEL.RadiusRatio = (MinorRad - Offset) / (MajorRad - Offset)
        End If
        
        If InOut = "Outside" Then
        Set NEL = ThisDrawing.ModelSpace.AddEllipse(Center, MajorAx, RadRatio)
        NEL.MajorRadius = MajorRad + Offset
        NEL.MinorRadius = MinorRad + Offset
        NEL.RadiusRatio = (MinorRad + Offset) / (MajorRad + Offset)
        End If
        
        If InOut = "Multiple" Then
        RepNum = ThisDrawing.Utility.GetInteger("Number of Offsets: ")
        ThisDrawing.Utility.InitializeUserInput 1, kwordList
        InOut = ThisDrawing.Utility.GetKeyword("Enter an option (Inside,Outside): ")
        Set NEL = ThisDrawing.ModelSpace.AddEllipse(Center, MajorAx, RadRatio)
        MjAx = NEL.MajorAxis
        MiAx = NEL.MinorAxis
        MajorAx(0) = MjAx(0)
        MajorAx(1) = MjAx(1)
        MajorAx(2) = MjAx(2)
        MajorRad = NEL.MajorRadius
        MinorRad = NEL.MinorRadius
        RadRatio = NEL.RadiusRatio
        If Not RepNum = 1 Then
            For i = 1 To RepNum
                If InOut = "Inside" Then
                    Set NEL = ThisDrawing.ModelSpace.AddEllipse(Center, MajorAx, RadRatio)
                    NEL.MajorRadius = MajorRad - Offset
                    NEL.MinorRadius = MinorRad - Offset
                    NEL.RadiusRatio = (MinorRad - Offset) / (MajorRad - Offset)
                        MjAx = NEL.MajorAxis
                        MiAx = NEL.MinorAxis
                        MajorAx(0) = MjAx(0)
                        MajorAx(1) = MjAx(1)
                        MajorAx(2) = MjAx(2)
                        MajorRad = NEL.MajorRadius
                        MinorRad = NEL.MinorRadius
                        RadRatio = NEL.RadiusRatio
                End If
                If InOut = "Outside" Then
                    Set NEL = ThisDrawing.ModelSpace.AddEllipse(Center, MajorAx, RadRatio)
                    NEL.MajorRadius = MajorRad + Offset
                    NEL.MinorRadius = MinorRad + Offset
                    NEL.RadiusRatio = (MinorRad + Offset) / (MajorRad + Offset)
                        MjAx = NEL.MajorAxis
                        MiAx = NEL.MinorAxis
                        MajorAx(0) = MjAx(0)
                        MajorAx(1) = MjAx(1)
                        MajorAx(2) = MjAx(2)
                        MajorRad = NEL.MajorRadius
                        MinorRad = NEL.MinorRadius
                        RadRatio = NEL.RadiusRatio
                End If
            Next
        End If
        End If
        Update
    End If
If RepeatMacro = True Then
GoTo Repeat
End If
End Sub

[RobertB]

Please consider the following comments as constructive criticism.

Your command prompts are formatted incorrectly. Options are supposed to be enclosed in square brackets ([ ]) and separated by forward slashes (/), e.g.:

"Enter an option [Inside/Outside/Multiple/Repeat]: "

You also have not provided the default condition. How does the user know what happens if they hit Enter? The default should be part of the option list and also included in angled brackets (< >) after the option list's square brackets.

The prompts should also display on a new line, e.g. vbCrLf & <string>.

Using GoTo statements is an indication that the code could use restructuring.