microstation sdk v8.11 - navigating programmatically through surface type 18

Roberto Cardosi said:

I have a cell containing an element of type Surface(18)

Type 18/19 surface/solid elements are primitive types.  They have been around since the last century.  They are neither B-spline surfaces nor BREP solids.  As a primitive type, they have no components (sub-elements).

One way to analyse a type 18/19 would be to convert it to a SmartSolid and use the SmartSolid API.

As Jan writes, the best API for analysing those primitives is MDL.  It's possible to determine how they were created (e.g. by extrusion or rotation) and the profile used to create that result.  Such methods are not available to you in VBA.

Dear all, many thanks for the answers.

I am a newbye in this community, so please forgive me for having not followed its best practices...

Public Sub NavigateThroughSurface(
        ByVal oApplication As Bentley.Interop.MicroStationDGN.Application
    )
        Dim oEnumerator As Bentley.Interop.MicroStationDGN.ElementEnumerator = oApplication.ActiveModelReference.Scan
        While oEnumerator.MoveNext
            Dim oElement = oEnumerator.Current
            If Not oElement.IsCellElement Then Continue While

            Dim oCellElement As Bentley.Interop.MicroStationDGN.CellElement = oElement.AsCellElement
            Dim lSubElementEnumerator As Bentley.Interop.MicroStationDGN.ElementEnumerator = oCellElement.GetSubElements
            While lSubElementEnumerator.MoveNext
                Dim oSubElement = lSubElementEnumerator.Current
                If oSubElement.Type = Bentley.Interop.MicroStationDGN.MsdElementType.Surface Then
                    'I do not find any "oSubElement.AsSurface" function...
                    'I have already done several tries, but without success:

                    '!!!!following statement throws exception:
                    Dim oBsplineSurfaceElement As Bentley.Interop.MicroStationDGN.BsplineSurfaceElement = oSubElement.AsBsplineSurfaceElement

                    '!!!!following statement throws exception too:
                    Dim lSolids As Bentley.Interop.MicroStationDGN.ElementEnumerator = oApplication.SmartSolid.ConvertToSmartSolidElement(oSubElement)

                    '?????????So how I can point to the surface itself and navigate through its subelements?????????
                End If
            End While
        End While
    End Sub

Jon Summers said:

One way to analyse a type 18/19 would be to convert it to a SmartSolid and use the SmartSolid API.

I have already tried to convert the subelement in SmartSolid, but following statement throws an exception:

'!!!!following statement throws exception too:
                    Dim lSolids As Bentley.Interop.MicroStationDGN.ElementEnumerator = oApplication.SmartSolid.ConvertToSmartSolidElement(oSubElement)

So, please may you better explain what you mean by "convert it to a SmartSolid"?

What is SmartSolid API and where I can find it?

Following screenshots show you the versions I am using:

Thanks in advance

Roberto

Roberto Cardosi said:

What is SmartSolid API?

Use SmartSolid.ConvertToSmartSolidElement(yourElement) to convert your type 18 element to an ElementEnumerator.  Then you can use the methods of SmartSolid and SmartSolidElement to perform your analysis.

Roberto Cardosi said:

following statement throws exception

VBA doesn't have exceptions.  What programming language are you writing?

I suggest that you write your initial program in pure MicroStation VBA.  It's hard for us to reproduce  VBA + some other language code.

That way, you won't get caught out by problems created at the interface of two different programming environments (e.g. VB.NET is not VBA) running in two different processes.  Once your VBA code is working, then you can consider porting to another language.

I have tried both in vba and in vb.net, but it does not work.

Following the link where you can download the very simple dgn file containing surface (type 18):

https://app.box.com/s/6v0ksnpohoskaypskc7s4lmfa89cfe7j

Here is the code in VBA:

Option Explicit

Public Sub Start()
    Dim oEnumerator As ElementEnumerator
    Set oEnumerator = Application.ActiveModelReference.Scan
    
    While oEnumerator.MoveNext
        Dim oElement As Element
        Set oElement = oEnumerator.Current
        
        If oElement.IsCellElement Then
            Dim oCellElement As CellElement
            Set oCellElement = oElement.AsCellElement
            
            Dim lSubElement As ElementEnumerator
            Set lSubElement = oCellElement.GetSubElements
            While lSubElement.MoveNext
                Dim oSubElement As Element
                Set oSubElement = lSubElement.Current
                
                Dim lSolid As ElementEnumerator
                Set lSolid = Application.SmartSolid.ConvertToSmartSolidElement(oSubElement)
                
                MsgBox ("if you read this message, then it works!")
            Wend
        End If
            
    Wend
End Sub

This code throws following error:

Here is the code in VB.net:

Private Sub Button17_Click(sender As Object, e As EventArgs) Handles Button17.Click
        Dim targetPWModel As String = "type1"

        Dim oApplicationObjectConnector As Bentley.Interop.MicroStationDGN.ApplicationObjectConnector = GetObject(, "MicroStationDGN.ApplicationObjectConnector")
        Dim oApplication = oApplicationObjectConnector.Application

        Dim oDesignFile = oApplication.ActiveDesignFile

        Dim oEnumerator As Bentley.Interop.MicroStationDGN.ElementEnumerator = oApplication.ActiveModelReference.Scan
        While oEnumerator.MoveNext
            Dim oElement = oEnumerator.Current
            If Not oElement.IsCellElement Then Continue While

            Dim oCellElement As Bentley.Interop.MicroStationDGN.CellElement = oElement.AsCellElement
            Dim lSubElementEnumerator As Bentley.Interop.MicroStationDGN.ElementEnumerator = oCellElement.GetSubElements
            While lSubElementEnumerator.MoveNext
                Dim oSubElement = lSubElementEnumerator.Current
                If oSubElement.Type = Bentley.Interop.MicroStationDGN.MsdElementType.Surface Then
                    'I do not find any "oSubElement.AsSurface" function...
                    'I have already done several tries, but without success:

                    Dim lSolids As Bentley.Interop.MicroStationDGN.ElementEnumerator = oApplication.SmartSolid.ConvertToSmartSolidElement(oSubElement)

                    MsgBox("if you read this message, then it works!")
                End If
            End While
        End While

        MsgBox("done")
    End Sub

And this is the error it throws:

Any other ideas?

Thanks again.

Roberto

I have tried both in vba and in vb.net, but it does not work.

Following the link where you can download the very simple dgn file containing surface (type 18):

https://app.box.com/s/6v0ksnpohoskaypskc7s4lmfa89cfe7j

Here is the code in VBA:

Option Explicit

Public Sub Start()
    Dim oEnumerator As ElementEnumerator
    Set oEnumerator = Application.ActiveModelReference.Scan
    
    While oEnumerator.MoveNext
        Dim oElement As Element
        Set oElement = oEnumerator.Current
        
        If oElement.IsCellElement Then
            Dim oCellElement As CellElement
            Set oCellElement = oElement.AsCellElement
            
            Dim lSubElement As ElementEnumerator
            Set lSubElement = oCellElement.GetSubElements
            While lSubElement.MoveNext
                Dim oSubElement As Element
                Set oSubElement = lSubElement.Current
                
                Dim lSolid As ElementEnumerator
                Set lSolid = Application.SmartSolid.ConvertToSmartSolidElement(oSubElement)
                
                MsgBox ("if you read this message, then it works!")
            Wend
        End If
            
    Wend
End Sub

This code throws following error:

Here is the code in VB.net:

Private Sub Button17_Click(sender As Object, e As EventArgs) Handles Button17.Click
        Dim targetPWModel As String = "type1"

        Dim oApplicationObjectConnector As Bentley.Interop.MicroStationDGN.ApplicationObjectConnector = GetObject(, "MicroStationDGN.ApplicationObjectConnector")
        Dim oApplication = oApplicationObjectConnector.Application

        Dim oDesignFile = oApplication.ActiveDesignFile

        Dim oEnumerator As Bentley.Interop.MicroStationDGN.ElementEnumerator = oApplication.ActiveModelReference.Scan
        While oEnumerator.MoveNext
            Dim oElement = oEnumerator.Current
            If Not oElement.IsCellElement Then Continue While

            Dim oCellElement As Bentley.Interop.MicroStationDGN.CellElement = oElement.AsCellElement
            Dim lSubElementEnumerator As Bentley.Interop.MicroStationDGN.ElementEnumerator = oCellElement.GetSubElements
            While lSubElementEnumerator.MoveNext
                Dim oSubElement = lSubElementEnumerator.Current
                If oSubElement.Type = Bentley.Interop.MicroStationDGN.MsdElementType.Surface Then
                    'I do not find any "oSubElement.AsSurface" function...
                    'I have already done several tries, but without success:

                    Dim lSolids As Bentley.Interop.MicroStationDGN.ElementEnumerator = oApplication.SmartSolid.ConvertToSmartSolidElement(oSubElement)

                    MsgBox("if you read this message, then it works!")
                End If
            End While
        End While

        MsgBox("done")
    End Sub

And this is the error it throws:

Any other ideas?

Thanks again.

Roberto

Roberto Cardosi said:

This code throws following error

CardosiEllipticalHead.dgn

I simplified your DGN model (removed the cell) and VBA code...

Option Explicit

Public Sub Main()
    Dim id As DLong
    id = DLongFromLong(4090)
    Dim oHead As Element
    Set oHead = ActiveModelReference.GetElementByID(id)
    Debug.Assert Not oHead Is Nothing
    Analyse oHead
End Sub

Public Sub Analyse(ByVal oHead As Element)
    Dim oSolidComponents As ElementEnumerator
    ' Next line throws 'unknown error'
    Set oSolidComponents = SmartSolid.ConvertToSmartSolidElement(oHead)
    Debug.Assert Not oSolidComponents Is Nothing
    Do While oSolidComponents.MoveNext
        Debug.Print "Found component type " & _
           CStr(oSolidComponents.Current.Type)
    Loop

End Sub

The code fails to convert the Type 18 to a SmartSolid in the line below my comment.

The DGN file and the VBA code provide evidence for a Trouble Report (TR) or Service Request (SR) you can file with Bentley Systems.  Or possibly Artur Goldsweer or Yongan.Fu can help?