The Building Coder

Handle Category Name Change

Here is a little note I wrote sitting in Washington Dulles airport and did not get around to posting until now, to point out the importance of using language independent category comparisons: Question: Apparently at least one category name changed in the German version of Revit from 2009 to 2010: Revit 2009: "Tragende Stützen" Revit 2010: "Tragwerksstützen" We rely on category names for mapping purposes. In this case we discovered the change that was causing problems for us, but I... Read more →

AU Virtual free for ADN Members

Kean Walmsley just announced that a free Premier Pass to Autodesk University virtual is available for members of the Autodesk Developer Network. Please join us there. We are presenting at both AUv and the non-virtual AU: Kean's F# sessions. AutoCAD-related AU and AUv sessions. The Revit Family and MEP APIs. I am looking forward to seeing or hearing from you in the next couple of days! Read more →

Visible Elements

I am sitting here cramped up in an economy seat crossing the Atlantic Ocean as I write this. I should urgently be practicing and preparing for my sessions at AU, but somehow it feels as if writing a blog post requires slightly less space, so here goes. I would also like to answer some pending comments, but cannot right now due to lack of Internet access... After revisiting the topic of selecting all model elements in the last post, there... Read more →

Select Model Elements 2

We already had several stabs at the topic of selecting all model elements, i.e. all elements in a Revit BIM which contribute to the building geometry. Their main characteristic is that they have a non-null geometry which is visible on the graphics screen and really contributes to the physical building model. Unfortunately, some elements which are not part of the building itself also have valid geometry and need to be eliminated. The latest version of the code that we presented... Read more →

Solid Material

Here is a simple question with a simple answer on materials and solids: Question: Is there a way to retrieve the material of the solid geometry object of a Revit Element, like the door leaf of a door element? Answer: No, I am not aware of any way that a material can be assigned to a solid. The only representation of the solid in the graphical user interface is through its faces, and they can have materials assigned to them.... Read more →

New Project Document

A short and simple question from Nadim on the NewProjectDocument method: Question: I am using Document doc = app.NewProjectDocument( string templateFile ); Revit shows that it is loading the template as it does usually when it creates a new document; however, it does not really create the new document. Any idea why? Answer: I implemented a sample external command CmdNewProjectDoc to test it for you and it works fine for me: const string _template_file_path = "C:/Documents and Settings/All Users" +... Read more →

Change Family Parameter Value

Here is another issue dealing with family parameters, after the notes on how to read the values of family parameters and looking at the family parameter values via the part atom export. Question: I'm using the AutoParameter SDK example to add parameters to my families. It was customized so that only specific parameters from the shared parameters file are added to the families (i.e. we have a large shared parameters file, and we only want certain ones added to these... Read more →

Nested Family

Here is another interesting question that came up on the creation of a nested family. Question: Can you help me to create a nested family via the API? I have a column family and a shelf family stored in RFA files, and I would like to implement a command which creates a new family with column and the shelf, and load it into a project. How can this be achieved? Answer: The solution to this task is quite easy. I... Read more →

Revit API Flavours

Maher raised an interesting question regarding the different flavours of the Revit API: Question: I have a few questions on Revit MEP, Arch, and Structure in general. What are the major highlights of each API? I downloaded the SDK and tried to read through. But could not get my head around it as it is very overwhelming. It would be great if you could post something in the difference between these three flavours both in terms of API and in... Read more →

Extract Part Atoms

Last week, we discussed how to use the Revit API to read the values of family parameters. Another quick way to access all non-empty parameter values in a family file and see some other interesting family data as well is to simply make a call to the Application.ExtractPartAtomFromFamilyFile method. It is mentioned in the What's New section of the Revit 2010 API help file. Its purpose is to export family data to XML for integration with Autodesk Seek. It opens... Read more →

Title Block of Sheet

Here is a question that crops up now and then in different variations, on how to access the title block information of a sheet: Question: My drawing list routine exports various sheet view information to a spreadsheet. I would like to include the name of the title block family that is associated with the view. What is the best way to find it? Do I need to loop through family instances, and do a reverse lookup? My snooping tool freaks... Read more →

Room Occupancy

Shifali asked a question on reading and writing the room occupancy: Question: We get the document from ExternalCommandData object's Application and the project information in document. We need to store the construction type of the current document or project file. Moreover, we get the Room elements of the document but we need to store the occupancy type of each room for applying the International Building Code for compliance reports of the project. We also need access to the BuildingConstruction and... Read more →

Family Parameter Value

Pramod asked an interesting question on obtaining the values of family parameters in a family document which led me to explore this topic and discover a little more complexity than I was originally expecting: Question: We are using the API of Revit Architecture 2010. We want to get all Parameters and their values from the Family document. We are referring to the AutoParameter example from the Revit SDK. With the help of this example, we are able to get parameters... Read more →

Ribbon Embed Image

Previous posts discussed the Revit 2010 Ribbon API, the associated Ribbon SDK Ribbon sample, and my use of it for the MEP sample ribbon panel. Krispy5 very friendlily posted a series of comments to the latter describing a detailed solution to embed the images used in the ribbon buttons into the Revit external application executable assembly. I implemented a sample application RibbonEmbedImage to make Krispy's solution more readable and readily available. This sample is obviously less a demonstration of any... Read more →

Product Support Subscription Videos

I mentioned the Revit 2010 Subscription Pack last week, and Matt Mason highlighted the model review add-in included with it and its little API, which is just one example of all the good stuff in there. Autodesk Product Support has now published a series of 'deeper dive' subscription pack videos which cover the subscription pack features and functionality and provide you with a deeper understanding of their use as well as anticipating and answering potential questions. Read more →

Autodesk University Extension

As already mentioned, I submitted the material for my AU sessions last week, and one of them is a virtual class which will be broadcast live worldwide for those who cannot attend AU in Las Vegas in person. Another option for people not travelling to Las Vegas besides getting the $99 Premier Pass to AU Virtual is provided by the Autodesk University Extension, which is a collection of over 100 completely free training events, held in 35 countries and hosted... Read more →

Model Review

We recently mentioned the subscription pack for Revit 2010. In addition to the product update itself, the subscription page for Autodesk Revit Architecture 2010 includes some new applications to complement Revit workflows to: Validate the accuracy of building information models against pre-determined standards. Import and export data between a Revit project and an external database. Facilitate the creation of 3D models from 2D digital photographs. These areas are obviously of great interest for developers as well. The first of these... Read more →

Adding a Column to RDBLink Export

Probably the most complex Revit SDK sample of all is the RDBLink one. We mentioned it briefly in Anthony Hauck's note on integration with a database or ERP system, but provided no additional details. Like all the SDK samples, RDBLink comes with its own readme document, which is actually a lot more extensive than most others due to the size and complexity of this sample. In brief, RDBLink demonstrates how to export Revit model data into an ODBC database and... Read more →