by Demetris Kekatos:     demetris.kekatos@gmail.com

This is a tutorial for amateur users of the VSTA Macro tools in Revit. After this tutorial you will be able to draw structural linear elements in Revit (beams, columns and braces) retrieving the geometry data from an open Excel spreadsheet.

     When transferring geometry from one software to another, Excel can become the mid step between the two software. For instance you can retrieve the start and end point of all the elements from a Grasshopper building model, print this data to an Excel Spreadsheet and then make the VSTA macro read this data  and draw the elements in Revit.

Even if you don’t have in mind to transfer elements from whatever software to Revit, this tutorial shows the way to draw beams, column and braces in general. So then you can use these tools to create a macro that draws towers  automatically for instance.

So we are going to start from the very beginning :   

Open a new Revit 2011 project and Save you project as importingGeometry

- In the Revit environment:

Go to the  “Manage” tab, click on the Macros icon and choose Macro Manager

 

-     The Macro Manager window pops up and here you can see two tabs . Application and a Tab with the name of the file. We will create a macro in the importingGeometry Tab, that means that the macro can only be used from this specific file.

Click on Create > Module

 Note: If we want to create a macro and it in different projects you have to create the same macro into the Application tab.

 

- Enter a name for the Module (continuous name with no gaps).  Select VB.NET as the programming language and before clicking OK you may add a description of what the macro does.

This will later help you when you have a list of different macros in Revit.

Now you are able to see your empty macro.

- Next step click on > Edit, in order to get into the macro and write our code.

 

- So our subroutine  “create Beams”  will be placed between the default subroutines that Revit places in this Class (called: ThisDocument)

Here we just imported a message box

 

- In order to make this simple macro work, we have to compile this first.

 Go to > Build > Build import_geometry

 

- After compiling the macro, we are able to use and Run it from the Macro Manager window.

 - Click on Run and a message will pop out:

Now we are sure that everything went through..

 back to the drawBeams tutorial, next steps:

Get access to Microsoft Excel from the VSTA Macro environment :

- The first step is to add the proper Reference file, that Revit will use in order to “talk” with Excel.

  Go to > Project > Add Reference…

On the COM tab choose the Microsoft Excel Reference as shown to the image below

 

- Next we have to import the namespace of Excel. Attention the best place to import namespaces in Revit VSTA is above all the default code that Revit imports in each macro

 

Before presenting the needed code I just want to refer what Revit needs to draw an element like a beam:

1. Start and End point of the element
2. The section of the element and
3. The level placed to the project

When coding it’s really important to know exactly what you need in order to achieve your goal… Now we are ready to write some code

Getting access to Revit model and the open Excel Spreadsheet:

'' method for creating Beams in Revit
Public Sub createBeams()
     MsgBox("Retrieve Beam Data")

     ''the first thing to do is get access to the Revit project
     Dim myModel As Autodesk.Revit.DB.Document
     myModel = Me.Document

     ''Get access to the active Excel Document
     Dim myExcel As Microsoft.Office.Interop.Excel.Application
     Dim myWorkBook As Microsoft.Office.Interop.Excel.Workbook
     myExcel = CType(GetObject(, "Excel.Application"), Application)
     myWorkBook = myExcel.ActiveWorkbook

     ''get access to the right spreadsheet
     Dim beam_sheet As Microsoft.Office.Interop.Excel.Worksheet
     beam_sheet = myWorkBook.Worksheets(1)
     'the number of the parenthesis sets the sheet we want to reach

 

Retrieve Element data from Excel:

''InputBox where the user is called to type the number of beams
Dim num_beams As Integer
num_beams = InputBox("Please enter the number of Beams...")

'' a loop to read data for each element from excel and draw it in Revit
    For i As Integer = 2 To num_beams + 1

    '' retrieve Start Point x,y,z
    Dim my_x1 As Double
    Dim my_y1 As Double
    Dim my_z1 As Double
    my_x1 = beam_sheet.Cells(i, 2).value
    my_y1 = beam_sheet.Cells(i, 3).value
    my_z1 = beam_sheet.Cells(i, 4).value
    '' retrieve End Point x,y,z
    Dim my_x2 As Double
    Dim my_y2 As Double
    Dim my_z2 As Double
    my_x2 = beam_sheet.Cells(i, 5).value
    my_y2 = beam_sheet.Cells(i, 6).value
    my_z2 = beam_sheet.Cells(i, 7).value

    '' retrieve beam section
    Dim section As String
        section = beam_sheet.Cells(i, 8).text

 

Finally draw elements into the Revit project:

''Transaction(in order to change the existing Revit model we always have to start a transaction)
Dim structure_builder As Autodesk.Revit.DB.Transaction
structure_builder = New Autodesk.Revit.DB.Transaction(myModel, "create Beams")

    '' lets create some beams
    If (structure_builder.Start() = Autodesk.Revit.DB.TransactionStatus.Started) Then

    ''set start point and end point of the element
    Dim start_point As Autodesk.Revit.DB.XYZ = Nothing
   Dim end_point As Autodesk.Revit.DB.XYZ = Nothing
   start_point = New Autodesk.Revit.DB.XYZ(my_x1, my_y1, my_z1)
   end_point = New Autodesk.Revit.DB.XYZ(my_x2, my_y2, my_z2)

   'define the element line
   Dim myBeamLine As Autodesk.Revit.DB.Line = Nothing
   myBeamLine = Autodesk.Revit.DB.Line.Bound(start_point, end_point)

   'load the Section of the element from Revit Structural Library
   Dim beamLibrary As String
   beamLibrary = "C:\ProgramData\Autodesk\RST 2011\Imperial Library\Structural\Framing\I_W_Wide Flange.rfa"
   Dim beam_sym As Autodesk.Revit.DB.FamilySymbol = Nothing
   Dim loaded As Boolean
   loaded = myModel.LoadFamilySymbol(beamLibrary, section, beam_sym)

   'define Levels
   Dim my_level As Autodesk.Revit.DB.Level

   'finally draw the beam
   Dim myBeam As Autodesk.Revit.DB.FamilyInstance = Nothing
   myBeam = myModel.Create.NewFamilyInstance(myBeamLine, beam_sym, my_level, Autodesk.Revit.DB.Structure.StructuralType.Beam)

   ''finalize the transaction and update model
   structure_builder.Commit()

   End If
Next

MsgBox("Macro Completed")

End Sub

Notes:

a. In order to draw the beam we have to load the right family of sections that Revit has in its database.  C:\ProgramData\Autodesk\RST 2011\Imperial Library\Structural\Framing\I_W_Wide Flange.rfa… So you have to find where Revit keeps the structural families in your system and paste the right path to this code.

b. About levels. We can realise that the levels are used in the code without defining a value. Giving the start and end point of the element Revit doesn’t need a level to place the element to the correct elevation

After importing the code we have to “Build” the macro and then run it from the Macro Manger Window

Don’t forget to create an excel spreadsheet with the proper info, because the macro will fail if it doesn’t find the source to read data

This is what you should get in Revit after running this macro…

 

To Conclude: This is the main body on how to create elements In Revit. For instance if you want to create braces or columns the whole logic is the same the only thing that changes is the last command:

''draw columns
Dim myColumn As Autodesk.Revit.DB.FamilyInstance = Nothing
myColumn = myModel.Create.NewFamilyInstance(myColumnLine, column_sym, my_level, Autodesk.Revit.DB.Structure.StructuralType.Column)

The part of levels is a bit tricky when creating columns.. This will probably be a subject in a following tutorial…

There are numerous ways to define the start and end point of an element and draw elements in Revit through VSTA macros. Hope this tutorial was informative…

Welcome to Revit Macros…