The Building Coder

ADN Training Material for Revit Structure 2014

Here comes the final step of migrating the ADN training material and The Building Coder samples to Revit 2014. The previous steps included: ADN Revit API training labs ADN Revit MEP sample AdnRme The Building Coder samples migration and deprecated API usage cleanup Now we turn to the final component, the ADN training material for Revit Structure, consisting of: Revit Structure training labs Revit Structure link sample NewRstLab RstAvfDmu The ADN Revit Structure Training Labs The ADN Revit Structure training... Read more →

What's New in the Revit 2014 API

Here is one post that I prepared well for in advance, by publishing the previous 'What's New in the API' sections two months back: What's New in the Revit 2010 API What's New in the Revit 2011 API What's New in the Revit 2012 API What's New in the Revit 2013 API The information provided here is extracted from the document 'Revit Platform API Changes and Additions.docx' provided with the Revit SDK. It is also included in the 'What's New'... Read more →

Basic File Info and RVT File Version

I presented an initial solution in Python for determining the version of an RVT file on disk from outside Revit making use of its OLE document Structured Storage format back in 2008. David Echols later shared a more full-fledged C# Revit OLE Storage viewer listing more information and displaying the preview image. Since then, the Revit API added support for reading basic RVT file info through the BasicFileInfo class. Victor Chekalin now presents another C# console application showing how some... Read more →

Set Detail Curve Visibility

Mostly, the Revit API limits an add-in to pretty high-level operations, encapsulating and protecting the parametric BIM from reckless modifications. For the nonce, here is a little bit of nitty-gritty bit manipulation anyway, in a utility method provided by Scott Conover: Question: Why is there no DetailCurve.SetVisibility method exposed, similar to ModelCurves.SetVisibility? The UI has this functionality, and I would find very good use for it in reinforcement detailing. I want to programmatically create a detail family representing a certain... Read more →

Roll Your Own Toggle Button

Today I took my first stab at creating, compiling and debugging a new Revit add-in on the Mac. I cannot run Revit or Visual Studio natively on the Mac, of course, so those have to remain in Windows, hosted by the Parallels environment on the Mac. I had to fiddle around quite a bit with the Parallels synchronisation, which seems to be breaking more things than it fixes, for me at least. I managed in the end in spite of... Read more →

Drive Revit through a WCF Service

Today, a special titbit for you: How can I access Revit functionality from an external process? As we have underlined many times in the past, the Revit API does not support any kind of asynchronous access. The Idling event, however, provides a possibility to work around this limitation. Daren Thomas, the author or RevitPythonShell, even presented a neat and clean pattern for semi asynchronous Idling API access. Now Victor Chekalin, aka Виктор Чекалин, presents another very neat sample providing such... Read more →

Beam Bottom Endpoint

Here is a nice little example illustrating different approaches to find the end point of the bottom centre line of an inclined beam. Question: I am trying to find the coordinates of the end points of the bottom centre line of an inclined beam. Depending on the beam angle, these coordinates will change. Here is a 3D view of the kind of situation I am looking at: The front view looks like this with the beam end points marked in... Read more →

Wall Footing Relationship Revisited

In the far distant past, I looked at various ways to programmatically determine relationships between associated objects (also in VB), including references between a host object and its hosted dependent elements, e.g. determining the relationship between a wall and its footing. That was back in the year 2009, using Revit 2010. A few things have changed and been added since then, but the more things change, the more they stay the same, don't they? Anyway, this very question was raised... Read more →

Structural Concrete Setout Point Add-in

I am back from my vacation now, having spent a wonderful relaxing time doing all kinds of things not related to the Revit API or computers at all, such as talking, walking, singing, playing music, painting, swimming, meditating, climbing, caving, canoeing and sharing time with friends... Meanwhile, a whole bunch of interesting issues to share with you have been piling up, new ones keep pouring in, and I still have some long-standing pending posts to get around to as well.... Read more →

Real-World Concrete Corner Coordinates

I mentioned that I worked together with Paul Hellawell of GHD on a full-blown end-user-capable little application for the automatic creation of setout points for on-site location and construction of structural elements at the Melbourne DevLab. Paul provided a description of the task and the initial idea for an implementation approach. We got the application to a useful working state in the two days during the DevLab, and Paul has provided it to his designers to use in real projects... Read more →

The Revit 2013 Structure API

I migrated the ADN Revit Structure API training material to Revit 2013, which led me to put together the following summary of the structural API enhancements and some details of the migration steps: API enhancements RstLabs migration NewRstLab migration RstAvfDmu migration Materials Revit Structure 2013 API Enhancements I mentioned a few structure specific enhancements in the Revit 2013 API. They are discussed in somewhat more detail in the DevDays Online presentation on What's New in Revit 2013 and the complementary... Read more →

Create Structural Plan View

Today is the last day of the last week before the AEC DevCamp in Waltham. Here are the complete session list and descriptions. I have to submit my material today. Before doing so, one last post on a pure API topic: I mentioned that Revit 2013 introduced a new view API and now includes the possibility to create schedules and section views. Here is a question that came up regarding the new view creation and Onebox and leads to a... Read more →

Section View Geometry Not Cropped

Here is a nice little chat with some interesting resulting hints that I had with an Australian programmer Bo that clarify the retrieval of geometry from a section view. The main point is that the cutting plane of the section view does affect the retrieved geometry, whereas the view's bounding box does not. Here is the path we took to clarify this in all its gory detail: Question: I am working on a structural concrete design application and would like... Read more →

Curved Analytical Model Approximation and Etabs Link

Here is a note on how to retrieve approximate straight line segments for the analytical model of curved structural elements, and on a free Revit Structural link tool to the Computers and Structures, Inc. (CSI) ETABS building analysis and design environment. A couple of weeks ago Nasser emailed me about a method he was trying to use for his Revit Structure link add-in. He was trying to export floor elements with curved edges to the structural analysis software ETABS. Like... Read more →

REX Content Generator

I had an absolutely magical experience in Israel before leaving Tel Aviv Thursday afternoon. Among many others at the developer conference on Wednesday, we met with Dima Brickmann of Omnitech, and he suggested going for a short visit to Jerusalem before returning to the airport, which is located between Tel Aviv and Jerusalem. Partha and I decided to join him. Dima has a very special relationship with the city and a deep philosophical and photographical view of it, so he... Read more →

Project Structure Generator on Autodesk Labs

I arrived safely in Las Vegas after a 12:40 hour flight to Los Angeles, 3:30 hour wait, und another flight of 1:05 hours. Pretty crazy. I had a headache after that, but not too bad, and I slept well out in the desert. Just like in previous years (08, 09, 09b, 10), my daytime jetlag therapy consists of climbing in Red Rock, this time with Sergio Colombo again, whom I first met and climbed with in 2008. We did the... Read more →

Analytical Model IsEnabled Method and Parameter

I recently mentioned the changes in accessing the analytical model in the Revit Structure 2012 API. We just discovered a little issue and an effective workaround related to the AnalyticalModel IsEnabled method, which reports whether the analytical model is currently enabled or disabled. Right now, it does not do that, but throws an exception for all members except walls. The Enable and CanDisable methods have similar problems. This will soon be resolved. Meanwhile, here is a simple workaround to avoid... Read more →

Bevelled Steel Beams

I recently mentioned a couple of options for performing Boolean operations. Here is another question which initially seemed related to that, from Simon Jones of Autodesk UK, on creating a mitre joint between steel beams, i.e. bevelling the two parts to be joined. It turns out to have a satisfyingly simple and automatic answer with no need for any explicit Boolean operations after all. Simon returned to a technical role in consulting after a period as Technical Sales Manager of... Read more →

Reference to Analytical Curve

The Autodesk University 2011 Class Catalog is now live and includes a full listing of both AU Las Vegas and AU Virtual Classes. Here are the my three classes: Lecture CP4451: Extensible Storage in the Revit 2012 API Hands-On Lab CP6760-L: Revit 2012 API Extensible Storage Virtual CP4453: Everything in Place with Revit MEP Programming So I have lots to prepare. For a full list of the classes presented by my colleagues in the ADN team, please refer to Kean's... Read more →

Retrieving Materials

Some people have reported issues using the Document.Settings.Materials collection. For instance, its Contains method may throw an exception when used with Revit Structure 2012, while it works fine with Revit Architecture 2012. The problem actually probably has nothing to do with the flavour of Revit being used, but is caused by the template file that the project is based on. If you retrieve materials in a project based on the architectural template in Revit Structure, it also works fine. In... Read more →

No Multithreading in Revit

I repeatedly hear from developers asking whether multithreading can be used in conjunction with the Revit API. The short answer is no. To our surprise, we just noticed that the Truss SDK sample does demonstrate a use of multithreading. That is an oversight and you should not rely on this working properly. Here is the considered statement of Scott Conover, Software Development Manager of the Revit API, on the current state of multithreading and Revit: "Revit's internals make use of... Read more →

The Revit Structure 2012 API

Sangsen recently submitted a couple of comments which made it clear that a short overview of the new features of the Revit Structure 2012 API is overdue (see below for the Q & A). Here is a description written by Joe Ye for our Spring 2011 ADN AEC newsletter: Autodesk Revit Structure 2012 API Migration Tips This article discusses changes made to the Revit Structure 2012 API. We will quickly go over the list of items which have been changed,... Read more →

Creating and Inserting an Extrusion Family

Today is the Pentecost or Whit Monday holiday in Neuchâtel, which gave me some time to explore an interesting and important issue in a bit more depth. Several developers recently asked about creating families programmatically, so here is a first simple example to demonstrate this. It creates a new structural stiffener family as an extrusion of a profile based on a list of XYZ points and inserts an instance of it into the current document. Here are the required steps... Read more →

Placing a Line Based Detail Item Instance

We already talked in depth about placing a detail family instance and the difficulties in selecting the right overload of the NewFamilyInstance method for that, a topic also discussed in the developer guide section 12.3.5 Creating FamilyInstance Objects, and its tables 34 and 35. As we already stated in that post, the exploration continues... Here is an interesting update to the issue by Frode Tørresdal of Norconsult Informasjonssystemer, which also highlights a new overload added in the Revit 2012 API:... Read more →

Wiki API Help, View Event and Structural Material Type

I am back again from my trip to Turkey and the attempt to climb Mount Ararat. Unfortunately, we were a bit unlucky with the weather on the day of our summit bid and forced to turn back at 4900 m, less than 200 m below the top, after spending several days on the mountain. We established a base camp just below the snow limit at about 2500 m, and a high camp in the snow at around 3500 m, and... Read more →

Slanted Column Cross Section Rotation

Here is a question that will be of most interest to people working with Revit Structure, on the different definitions of the cross section coordinate system of vertical versus slanted columns, with several people chipping in to answer it from various perspectives. The solution is illuminating and highlights one significant difference between objects whose Location property is a LocationCurve versus a LocationPoint. Question: Is there any rule or documentation on the definition of the cross section coordinate system orientation for... Read more →

Structural Analysis Links to Revit Structure

We had a look at available Revit Structure API resources almost a year ago, and also published the ADN Revit Structure labs and an analysis link sample. Furthermore, we discussed the enhancements made in the Revit Structure 2011 API, but the labs and link samples published are still based on Revit 2010. Let's update that to Revit Structure 2011 right here and now: here is rst_src_2011-03-01.zip. It includes the ADN DevTech labs and link sample code previously discussed, as well... Read more →

Joined Beam Geometry Access

We have already discussed situations where an element's geometry needs to be accessed in various ways depending on the circumstances, such as the retrieval of unmodified element geometry or the different approaches required to access column and stair geometry, depending on whether the element has its own solid definition or is reusing the solid defined by the symbol it references. Here is a similar solution to obtain the geometry of a beam joined with columns from my colleagues Katsuaki Takamizawa... Read more →

Optimisation using Robot Structural Analysis API

After mentioning a very simple example of using the Revit Structural analytical model to find connected structural elements two days ago, here is a presentation of some more advanced structural optimisation in case you are interested in going further in this area, beyond the pure Revit API: Al Fisher and Shrikant Sharma of UK-based Buro Happold Engineers published a whitepaper on exploiting the Autodesk Robot Structural Analysis Professional API for structural optimisation. Its introduction says: Access to an open API... Read more →

Finding Connected Structural Elements

We had some glimpses in the past of the structural analytical model maintained by Revit Structure, e.g. when looking at The AnalyticalViewer SDK sample Revit Structure API Resources The NewLineLoad method Analytical support tolerance An overview of geometry options The Revit Structure 2011 API Here is a very basic question that can be addressed using the analytical model: Question: Is there any way to find connected structural elements? For example, to find columns from a connected beam, or beams from... Read more →

Find Intersecting Elements

Right now I am sitting in the Tel Aviv Ben Gurion airport, which very friendlily provides free public wifi Internet access, unlike the also very friendly staff with an unfortunately less generous wifi policy in the Sheraton hotel we stayed at, who (try to) charge USD 20 per day for the same service. Yesterday we looked at the XML family usage report from Kevin Vandecar's filtering and optimisation presentation at the AEC DevCamp conference in Boston in June, which formed... Read more →

Bienvenue à StructureBIM

A new French language Structural Engineering BIM blog is born: StructureBIM. It is mainly focused on Autodesk Revit Structure, Autodesk Robot Structural Analysis, AutoCAD Structural Detailing, and authored by Alexandre Mihalache, Olivier Bayle, Stéphane Balmain and Emmanuel Lagardette. Welcome to the Revit blogosphere! Read more →

Adding a Rebar inside a Rebar Cover

The Pantagruel arrived safely in Göteborg last night after our week-long tour of Norway, Denmark and the Swedish west coast, and our last day has arrived. Time to clean up, disembark, go to the airport and return home again. Meanwhile, here is an interesting structural rebar issue raised by my colleagues Katsuaki Takamizawa and Tim Culver: Question: Here are some rebars that were created using the Revit API NewRebar method: In the user interface, rebars can only be added inside... Read more →

Immutable PointLoad Force

Today we crossed the Kattegat from Læsø in Denmark to Rörö in Sweden, north of Göteborg, so we have finally arrived in the archipelago on the west coast of Sweden. As said, you can follow our exact route on the Pantagruel tracker. We spent more than 48 hours at sea when going from Norway to Denmark, with some very beautiful moments, among others the night watches with more stars than you can imagine. I saw four shooting stars the first... Read more →

Structural Dynamic Model Update Sample

I am away again on the next leg of my extensive vacations this summer, travelling a bit further afield this time. After one night in a plane and another night in a bus I find myself on the island of Ko Tao in Thailand, where I completed my first open sea water dive in the Japanese Garden with Boris of Alvaro Diving. Since I will be away for the whole month of August, I decided to take the computer with... Read more →

Retrieve Structural Elements

I recently discussed the retrieval of all Revit MEP elements and their connectors. Here is a similar question on retrieving structural elements: Question: How can I get all the structural elements like structural walls, slabs, columns, and beams from the model? I have a problem with the columns and beams because they are family instances and I cannot just check only their type. I currently have to go through all the family instances and check whether they are a column... Read more →

The Revit Structure 2011 API

Since I talked about the Revit MEP API yesterday, I should be fair and mention the Revit Structure API as well, shouldn't I? Last year, we provided an overview over a number of Revit Structure resources, including pointers to the structure related webcasts, samples, trainings and Autodesk University classes available in the Revit 2010 timeframe. Here is a quick tour by Joe Ye of what has changed in the Revit Structure 2011 API as well as new enhancements. Changes in... Read more →

Revit 2011 API Webcast

Here is a last-minute reminder to register for the Revit 2011 API webcast that we are holding on Wednesday April 21st, in eleven hour's time. To register, you can visit the Autodesk Developer Network (ADN) DevTech API training schedule site, filter for 'Revit 2011 New APIs', and click on the register link. This webcast is open to all developers, regardless of ADN membership. Sorry for the late notice, I was too caught up in the discussion on the regeneration option... Read more →

Beam Requires Curve

We discussed the issue of inserting a beam and also creating a curved beam in some depth already. The former discussion includes a pretty detailed analysis showing that you really do have to specify a curve in order to generate a valid beam instance, and all other overloads of the NewFamilyInstance will fail in one way or the other. In spite of this, people continue having problems inserting beam instances. My colleague Joe Ye just encountered another case like this:... Read more →

Vertical Projection of Beam Analytical Model

We tried to fly from Milano to Paris this evening for the last DevDays conference, but unfortunately our flight was cancelled due to snow in Paris. Now we are stuck at the Milano airport and hoping that the first flight in the morning will not be cancelled as well. If it is, we will not be able to make it at all. Otherwise, we will arrive rather late and have to reschedule the agenda, but at least then we will... Read more →

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 →

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 →

Analytical Support Tolerance

Here is an interesting issue dealing with the analytical model in Revit Structure. As we see below, the issue is not really API related, but since one symptom is the missing data obtainable through the API, it is worth an explanation. Question: We have created two columns over a three-pile cap foundation and are trying to retrieve the support data from their analytical models: Unfortunately, the support data of the column is available only if its centre line is exactly... Read more →

Practical Notes on Impractical Things

I just learned that the two introductory images presented in the article on the Revit form creation API came from Zach Kron, whose blog Buildz presents lots of interesting 'practical notes on making impractical things' in Revit. Here is a pointer to a completely different kind of practical note on another blog: Disable Auto Setback in Framing Template Several developers have been struggling with some of the hard-coded Revit behaviour. Miroslav Schonauer just pointed out that he and Sarah Capes... Read more →

NewLineLoad

In Revit Structure, a new line load is created using the NewLineLoad method. It provides four different overloads, which we wish to explore here in a little more detail: NewLineLoad(XYZ, XYZ, XYZ, XYZ, XYZ, XYZ, Boolean, Boolean, Boolean, LineLoadType, SketchPlane): unhosted line load using data at two points. NewLineLoad(XYZArray, XYZArray, XYZArray, Boolean, Boolean, Boolean, LineLoadType, SketchPlane): unhosted line load using data at an array of points. NewLineLoad(Element, XYZArray, XYZArray, Boolean, Boolean, Boolean, LineLoadType, SketchPlane): hosted line load using data at... Read more →

Language Independent Category Access

I recently discussed category comparison, and I keep stressing the importance of keeping the application implementation language independent as far as possible. Jiri Smerak of Ing.-Software Dlubal GmbH now uncovered a situation in which due to a localisation issue the language independent category comparison is in fact the only way to access certain categories in the German version of Revit Structure. The issue has to do with the following built-in categories: OST_LoadCasesLive OST_LoadCasesRoofLive OST_LoadCasesSnow OST_LoadCasesWind When trying to access these... Read more →

Creating a Curved Beam

Here is a solution from my colleague Joe Ye on how to create a curved beam. This is also the first and so far only Building Coder sample that demonstrates the use of the Revit API DoubleArray and NurbSpline classes. Question: I am creating curved beams using NURBS. When the spline in parallel to the XY plane, all works well: When the curve is lying in the YZ or XZ plane, however, the resulting beam is straight: How can I... Read more →

Creating a Slanted Column

We already discussed the creation of beam and column instances in previous posts. In that post on the beam insertion, we explore setting arbitrary start and end points, but the column is left in its default vertical alignment. Here is a question specifically targeted at the creation of slanted structural columns handled recently by our DevTech AEC workgroup leader Mikako Harada: Question: I cannot find any help to explain how to create a slanted column through the API. Please explain... Read more →

Host Reference

Still enjoying my climbing and sunshine holiday with my sons in Avignon. Yesterday we went climbing and exploring the cliffs or 'calanque' of Cassis, east of Marseille (more images): Besides climbing, swimming in the Gard river and Mediterranean Sea, and blogging now and then, my sons are also artistically active: Returning to the Revit API, however: We already touched on the relationship between a host and its hosted elements in some previous posts. The first such topic was the relationship... Read more →

Core Structural Layer

Question: How can I identify the core structural layer in a Revit host element such as a floor or a wall? Answer: A heuristic method for this might be searching for the thickest layer. Here is a VB example of searching for the thickest layer of a given floor type and identifying its material, using its CompoundStructureLayerArray layers: Dim m As Material = Nothing Dim layers as CompoundStructureLayerArray = floorType.CompoundStructure.Layers Dim thicknesses(layers.Size) As Single For i As Integer = 1... Read more →