The Building Coder

Display a Geometry Debugging Point in the Model

Here are some pointers from a conversation I had with Daren Thomas on how to display a reference point in the model for debugging purposes that may be on general interest. Question: I am playing around with the FindReferencesWithContextByDirection method and would like to display the references found as coloured blobs or something in the model. How can I achieve this, please? This question could also be simplified into: how to create an easily visible dot at a 3D point... Read more →

The Temporary Transaction Trick for Gross Slab Data

Last week I provided an updated version of the CmdSlabBoundary external command to determine a floor slab boundary. Here is a follow-up to that issue: Question: The solution provided to retrieve the slab boundary works fine for me if no openings are cut out. I have a situation where my slabs are cut by openings, however, and I need to retrieve the original uncut gross slab boundary. Here is an example with two slabs A and B and an opening... Read more →

Ensure WPF Add-in Remains in Foreground

Autumn arrived and passed in a flash. The woods are beautifully coloured, and, unusually, the first snow is already lying on the surrounding hills. Here are some items of interest from cases we looked at last week: Ensure WPF add-in remains in foreground Retrieve all model lines Set linked file visibility Access linked file elements and data Visual Studio 2012 Model Editor Supports OBJ and FBX Sie Mögen Sich Ensure WPF Add-in Remains in Foreground Here is an issue concerning... Read more →

Stair Geometry and Roombook

A long time back we touched on the difficulties and challenges in retrieving column and stair geometry. From Revit 2013 onwards, you have full API access to create and read data from stairs and railings, as well as their separate subcomponents, as you can see from this excerpt of the What's New section in the Revit API help file RevitAPI.chm: Stairs and Railings API – Stairs and Stair Components The new Stairs and StairsType classes in the Autodesk.Revit.DB.Architecture namespace provide... Read more →

PowerPoint Slide Deck Text Extractor Ppt2txt

Here is another longish post that is not directly related to the Revit API, but rather Microsoft Office programming, more specifically PowerPoint. However, the sample material I present at the end is very directly related to Revit programming, so rest assured that all is well and hopefully interesting. Contents: Slide deck and handout document Slide deck comparison and text extraction Alternative comparison method Ppt2txt usage Ppt2txt implementation Ppt2txt download Formatting in Word Sample run Slide Deck and Handout Document The... Read more →

Revit 2013 Update Release 2

Revit 2013 Update Release 2 is now available. I found a path to the Revit Architecture update via Autodesk Revit Products > Services & Support > Service Packs & Downloads > Autodesk Revit Architecture > Updates > Revit Architecture 2013 Update Release 2. Phew. That was rather hard. A much easier way to reach the exact download I am after is to enter the appropriate string in Google. That takes me directly to the download page with no need to... Read more →

Room Polygon and Furniture Picker in SVG

I documented a number of personal and possibly naive ideas and experiments regarding mobile device room location as a result of my previous so-called education day four weeks back. Well, last Friday I had another one :-) This time I took a deeper and hopefully very slightly wiser look at ideas for enabling the following kind of workflow: Extract relevant data from the BIM. Populate a cloud database to provide ubiquitous access to relevant data. Serve up relevant data in... 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 →

Deleting a GraphicStyle Element

Here is a short and sweet deletion question handled by Joe Ye: Question: I am trying to delete a GraphicStyle object in a RFA family document. I tried to achieve this using the following code, but it was not successful: Dim elem As Element = m_rvtDoc.Element( "5ad9f0cf-6eff-4c63-8a44-9f3a87881dd7-00000b22") m_rvtDoc.Delete(elem) How can I delete this object? Answer: Some internal line style objects cannot be deleted, because the model requires their presence. As you can see in the following image, the Delete and... Read more →

Sweep PickPath Tolerance Criteria

Here is a rather specialised and hitherto undocumented topic of great importance to anyone trying to model precise complex swept geometry. The issues below arose exploring the tolerance requirements of the 'Pick Path' options in the Revit UI, which map to the ReferenceArray and Reference input to the two FamilyItemFactory API calls for generating this kind of geometry: Sweep NewSweep( bool isSolid, ReferenceArray path, SweepProfile profile, int profileLocationCurveIndex, ProfilePlaneLocation profilePlaneLocation ); SweptBlend NewSweptBlend( bool isSolid, Reference path, SweepProfile bottomProfile, SweepProfile... Read more →

Porting an AutoCAD Application

AutoCAD and Revit are very different animals, as we already pointed out a couple of times in the past. Exaggerating just a little, you might say that Revit manages a BIM and ensures its consistency at all times, so there are no exceptions to anything ever, meaning nothing can be overridden. Moreover, almost all Revit geometry is parametrically driven, so there is no way to tweak the model geometry either, except of course by changing the official parameter values. This... Read more →

Point Cloud Request Batching

Here is some important information for point cloud engine developers, who may be confused by the SDK samples provided. Question: We have taken the Revit point cloud engine example provided and modified it to create three cells, each loading its points from an ASCII file. The cell boundary is then drawn as blue random points. We noticed that the maximum number of points ever requested is 512 * 512 and decreases as you zoom out. This number is applied to... Read more →

UIView, Windows Coordinates, ReferenceIntersector and My Own Tooltip

Here is my well-meant contribution to making this the most exciting Wednesday of your entire week. For the first time in history, the Revit 2013 UIView class provides a possibility to convert back and forth between Revit model coordinates and Windows device screen points. I imagined making use of that right away when I read about the UIView class, and mentioned it when discussing UIView and Windows device coordinates. I am still a bit surprised that I have not yet... Read more →

Slab Boundary Revisited

After yesterday's rejuvenation of the old wall footing host reference relationship detection, today raises another old question prompting me to update and retest The Building Coder samples yet again: Question: How can I obtain the boundary of a floor slab using the Revit API, please? Answer: I implemented a CmdSlabBoundary external command to determine the slab boundary back in the dawn of time, in 2008, in one of the first posts on this blog. It determines the boundary edges of... 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 →

Detach Workset and TaskDialog Command Link Order

Here is a neat and simple solution using the DialogBoxShowing event to detach and discard worksets by Erik Eriksson of White Arkitketer AB, who already provided a useful workaround to synchronize with central using SendKeys in combination with the Idling and DocumentSynchronizedWithCentral events. Here is the issue: Question: We have a need to detach project files without worksets. For instance, it would be great to just have an option to detach and discard worksets. Why do we need this? This... Read more →

Ribbon Creation Utility

Creating and populating a ribbon panel is not a very complicated matter, although it normally does require instantiating and manipulating quite a number of different cooperating class instances. Now Victor Chekalin, or Виктор Чекалин, presents a much simpler solution for this using dedicated wrapper classes. In his own words: Create Buttons without Effort As you know, you can create your own buttons or even your own tab in the Revit ribbon to perform a command. For me, creating button always... Read more →

Element Intersection

A common question when analysing a BIM is determining whether any of its elements intersect. This was actually surprisingly difficult to answer programmatically in Revit a few releases back, as some of the interesting uses of the FindReferencesByDirection method show, for example the FindColumns SDK sample. Later, that method was enhanced to lead to FindReferencesWithContextByDirection. The FindColumns sample searches for intersections between walls and columns by shooting a ray along the wall centre line, raised above the bottom level by... Read more →