The Building Coder

No Geometry, Touching Geometry and Cut Geometry

Discussions of BIM, geometry, pyRevit and AI news – pyRevit discourse – The BIM has no geometry – Get touching elements – What is a stable representation of a reference? – CUT_EDGE reference voodoo – Revit and IFC coordinate systems – Chinese influencer deepfakes livestreaming 24/7 – Generative AI use and misuse... Read more →

IFC, Dimension and Reference Intersector with Links

Pros and cons of the reference intersector and how to use it with linked files and filtered element collectors, a design automation IFC exporter, dimensioning linked elements using the reference stable representation and new forays with large language models – Reference intersector with filters and links – Revit IFC exporter for APS DA – Stable representation voodoo with links – Running Dalai LLaMa locally – ChatGPT invented a game... Read more →

Element Level and IFC Properties

Tips on handling IFC and recent discussions on controlling the level of BIM elements – TwentyTwo add-ins and tutorials – IFC tips for APS and Forge – IFC custom properties in Revit – Set level id of existing element – Set level in NewFamilyInstance... Read more →

Deleting Storage and Picking a Symbol

Interesting hints from the forum and thoughts on feedback, community and communication – Unload IFC links to delete extensible storage – Picking, selection and UI design – Feedback is always a great gift – Scott Peck and community building... Read more →

Unique Id and IFC GUID Parameter

We take yet another look at element ids and maintaining connectivity with IFC GUIDs – Linking IFC export with modified BIM – You cannot control the unique id – You can control the IFC Export GUID... Read more →

Purge Unused and eTransmit for DA4R

Today, we return for a summary and a new, deeper look at a recurring topic – eTransmit documentation – Purge via performance advisor – eTransmit functionality in DA4R – Updated Autodesk Revit IFC manual – AI solves programming tasks... Read more →

Addin File, Learning Python and IFC.js

Today, we look at the add-in manifest, learning Python and Dynamo, the status of the Revit Python shell and a useful stand-alone IFC viewer – Personalised add-in manifest – Learning Python and Dynamo – Quo vadis, RevitPythonShell? – IFC.js... Read more →

IFC 21.1 and AEC Hackathon Presentations

More on Revit 2021.1, IFC 21.1, and nearing the end of the AEC Hackathon – Revit 2021.1 questions – IFC 21.1 released – AEC Hackathon final presentations... Read more →

Unit Testing and the UsesInstanceGeometry Method

Quick notes on two recent interesting Revit API discussion forum threads – Unit testing – UsesInstanceGeometry IFC utility method... Read more →

Curve Projection, Detach and FBX in DA4R

Two little hints on Forge Design Automation for Revit or DA4R issues, projecting a curve onto a planar surface and an impressive list of add-in video samples – DA4R supports FBX and IFC – DA4R wrong user – Projecting curves onto a plane – Revit add-in versus Dynamo zero-touch node – Revit add-in sample videos... Read more →

IFC Update, Instance Geometry, Parameters

I completed the move to my new computer, and happily all systems go now. Here are some other topics that came up in the past few days – Revit-IFC Release 20.1.0 – Community discussion on Revit – Solid or instance, depending – Exporting parameters to Access – Store globals on custom DataStorage, not ProjectInfo – Iranian civil engineering project video... Read more →

Element Identifiers in RVT, IFC, NW and Forge

A recent internal discussion clarifies Revit element identification in Forge, Navisworks and IFC, some new thoughts on consciousness versus AI, and a couple of topics of personal interest – Two Nice summer mountain hikes – Revit element ids in Forge via Navisworks and IFC – Some aspects of consciousness may be beyond reach of ai – Trees might help against global warming – Holidays ahead... Read more →

Room Closed Shell DirectShape for Forge Viewer

I explored three main topics here at the Forge accelerator – Room closed shell solid visibility in the Forge viewer – Rebar simplification: replace rebar elements with simplified solids or model curves – glTF export – Today, I'll dive deeper into the first – IFC exporter utility adds new built-in parameter – Barcelona Forge accelerator – Room closed shell in the Forge viewer – Triangulate the solid face by face – Triangulate entire solid – Tessellation accuracy control documentation error... Read more →

Forge DA4R IFC Support and Snoop Enhancements

Let's close this eventful week with two important enhancements added to the Forge Design Automation API for Revit and our beloved RevitLookup tool – IFC Support in the Design Automation for Revit API – RevitLookup Snoop Enhancements... Read more →

Assigning a Level to an Element Missing It

I recently implemented the IfcSpaceZoneBoundaries add-in to link in and analyse IFC file zones and spaces, then prepared it for use in Forge Design Automation. Now I want to add level information to the CSV export. However, the DirectShape elements created to represent the rooms and zones have no valid level assigned, so their Level property is invalid. Happily, we can easily analyse the BIM and generate the equivalent information ourselves – Retrieve levels sorted by elevation – Determine level from element elevation – Carl Bass and Zoox autonomous vehicles – Physical reasons to be happy to be alive... Read more →

Preparing a Revit Add-in for Design Automation

Today I discuss the next step in my IfcSpaceZoneBoundaries project, how to prepare a Revit add-in for use in the DA4R or Design Automation for Revit environment and figuring out how to best handle it in the VS solution – Context, add-in functionality and history – Preparing the add-in for DA4R – Local testing versus live deployment – User defined input arguments for DA4R – Logging of results... Read more →

Link in and Analyse IFC File Zones and Spaces

I am working on extracting room and zone information from IFC files, both geometry and relationships, specifically room and zone boundaries and containment. My new IfcSpaceZoneBoundaries add-in project retrieves this information, exports it to CSV and demonstrates a host of other important aspects – What happens on linking in an IFC file? – Read user configuration input settings from a file – Log messages, warnings and errors to an output file – Read the IFC properties stored as shared parameters – Extract the horizontal boundary information from a DirectShape element – Export the relevant data to CSV – Programmatically link in an IFC file into a Revit RVT project – Retrieve all currently linked-in IFC files from the Revit application... Read more →

Retrieving Linked IfcZone Elements Using Python

Today, I present a little exploration of how to access zones defined in an IFC file in Revit. If you are following this blog closely, you might guess that this is related to the room boundary CSV exporter project that I recently discussed. For this exploration, I installed and used RevitPythonShell. Here are the detailed steps – Importing IFC zones into Revit – Installing and using RevitPythonShell – Programmatically accessing IFC zones in Revit... Read more →

Tailor Your BIM with F#, Forge, IFC and Takeoffs

I have a whole bunch of exciting overdue topics lined up. Let's start with these – Tailor Your BIM sums room areas with F# – Control view for design option elements with F# – Copy legend view and component from background file – Forge RVT to IFC translation defaults to 2x3 – Latitude and longitude in Revit IFC export – Takeoff creation requires branch duct... Read more →

Wall Profile Command Update

I returned from my time off in July. I dived in deep into the Revit API again to resolve an issue retrieving wall profile curves. Here are some other noteworthy items to keep company with my debugging report – CmdWallProfile update – Access to the IUpdater original value – Getting element dimensions from IFC files – Creative workaround to rotate elevation marker in chunks... Read more →

Forge RVT to IFC, ADN Xtra, TBC, AdnRme Updates

I already described how I installed Revit 2019, compiled the Revit 2019 SDK samples and migrated RevitLookup to the new version. I now migrated some of the other basic samples and utilities and have some Forge news to share – The Building Coder samples for Revit 2019 – The AdnRme MEP HVAC and electrical samples for Revit 2019 – AdnRevitApiLabsXtra for Revit 2019 – Convert RVT to IFC via Forge – Forge accelerators – Forge webinars – Open position for an infrastructure BIM implementation consultant... Read more →

Copy Local False and IFC Utils for Wall Openings

New important issues are researched and brilliant solutions shared daily in the Revit API discussion forum. Here are two from the current crop – IFC helper returns outer CurveLoop of door or window – Setting Copy Local to False resolves AddIn Manager issue... Read more →

Forge Formats Python Script and IFC Open Shell

I went back to answering way too many questions in the Revit API discussion forum yesterday. However, two other interesting topics also cropped up when I finally let go of that pastime, and I just finished a good book – The Sellout by Paul Beatty – IFC Ids and Open Shell – Forge Python scripts – py_forge_formats.py – forge_authenticate_app – forge_formats – jprettyprint – Mainline... Read more →

AU Day Two, IFC and Revit API Panel

The second day. I finally got to attend Angel Velez' IFC class – it always clashed with my own in previous years – followed by the product keynote and the Revit API panel discussion – Angel Velez on IFC – Product keynote – Revit API panel – Panel members – Questions and answers – Notes from previous Revit API panel sessions – Session materials... Read more →

Consistency of IFC GUID and UniqueId

Angel Velez provided further clarification on the relationship between the Revit element UniqueId and the IFC GUID generated from it, prompted by the Revit API discussion forum thread on abnormal modification of Element.UniqueId... Read more →

IFC Import and Open Source

Quite a few issues revolving around IFC came up lately in various ADN cases and in the Revit API discussion forum. Before getting to the technical stuff, some pictures from my latest mountaineering trip to climb Gross Spannort – Autodesk Forge Platform — Little machines – IFC import scaling issue – IFC open source C# library – Customising IFC import – IFC family support... Read more →

IFC Import Levels and MEP Element Shapes

I answered far too many threads on the Revit API discussion forum in the past few days to list them all, so I'll just pick out two cases of special interest today – Levels generated by IFC import – Determining MEP duct and pipe element shape... Read more →

Sharing, Dynamo and a Chinese Book

I returned from the Autodesk Cloud Accelerator in Prague, where I finished off cleaning up the FireRating in the Cloud sample and made some good inroads into the new CompHound project. Some learning resources and sharing philosophy – Håvard Vasshaug on Learning Dynamo and Sharing Content – Open Source BIM, IFC and FreeCAD – Chinese Revit API Book... Read more →

IFC GUID Access, Life Span and Cloning of Geometry

Today, let's talk about the life span of Revit geometry and accessing the IFC GUID of an imported element: Life span and cloning of solids and faces Accessing the IFC GUID of an imported wall First, I'll just mention that I returned safe and sound from the successful fourth and last day of the Milano WebGL workshop, which we concluded with a group session guiding through the View and Data API tutorial. I wrote is a short report on that... Read more →

IFCExportUtils Determine Door and Window Area

Last week we discussed the SpatialElementGeometryCalculator sample for calculating gross and net wall areas that in turn led to the discovery of the FindInserts method to retrieve all openings in a wall. Both of these were prompted by the Revit API discussion forum thread on door/window areas raised by Phillip Miller of Kiwi Codes Solutions Ltd. Another question that arose in that thread regards the meaning of the built-in parameter HOST_AREA_COMPUTED and how to best calculate the area of a... Read more →

Getting the Wall Elevation Profile

I am back from the vacation in Italy, which I enjoyed very much, especially another visit to the wonderful coast of Amalfi. To quickly share an interesting new result using the Revit API, here is a solution by Katsuaki Takamizawa to retrieve the wall elevation profile. It also provides a nice little example of using the ExporterIFCUtils.SortCurveLoops method that we just recently documented. Says Katsu: I created some sample code for finding the wall elevation profile and determining its outer... Read more →

ExporterIfcUtils Curve Loop Sort and Validate

Joel Spahn raised a pertinent question on sorting face loop edges that was kindly picked up and answered by Scott Conover and Angel Velez from the Revit development team: Question: It would be nice to know exactly what the following methods do: SortCurveLoops: sorts a set of curve loops such that outer and inner loops are separated. Remarks: Outer loops are separated and inner loops are grouped according to their outer loop. Loops are assumed to be non-intersecting, and there... Read more →

Cloud Accelerator and More Revit Stuff

Last opportunity to make one more New Year's Resolution! Submit a proposal for the cloud accelerator: Cloud Accelerator Revit API Discussion Forum Activity C# Samples and Getting Started with the Revit API 2D Coordinates of Curve Endpoints in View3d Edit IFC Import to Write Extensible Storage Cloud Accelerator Talking about opportunities to dive deep and fast into cool web oriented technology, check out the Autodesk Cloud Accelerator, a two-week workshop in March 2015 in our San Francisco office for up... Read more →

Embedding an Interactive View and Data IFC Model

Here is an interactive 3D sample embedding of an IFC file uploaded to A360 to answer a question in this morning's DevDays conference here in Munich: Click to navigate, rotate, pan and zoom as you like. I was prompted to upload and test the IFC file format translation by Adam Nagy, sitting together in the back row, after taking neat pictures of Cyrille's new headset: I simply grabbed an old sample IFC file (6.5 MB) I had sitting on the... Read more →

DirectShape versus Families, Category and Texture

Let's begin this week with a discussion of several aspects of direct shapes: Direct shapes, part families and application porting DirectShape categories DirectShape texture assignment Direct Shapes, Part Families and Application Porting Question: I am looking for some guidance related to porting my application to Revit. I have a parametric part engine that lives outside of Revit with a large set of existing library content. It would be very costly to rebuild from scratch using the Revit Part Family editor... Read more →

IFC GUID Algorithm Update and Family Modification

Two short topics for today, an important little IFC GUID algorithm bug fix and some thoughts on detecting family modification. IFC GUID Algorithm in C# Update Håkon Clausen implemented a bug fix update and created a GitHub repository for the IFC GUID algorithm in C# that he originally published back in June 2010. Here are the details on the update and a direct link to his IfcGuid GitHub repository. Detecting Family Modification For ages, content creators and developers have been... Read more →

Properties in DWF, IFC, Tables and Extensible Storage

Let's discuss a couple of questions that accumulated recently on various aspects of properties in general: Properties in DWF export Mapping Revit and IFC properties Storing a table in a project Updating versus adding new extensible storage schemas Before getting to that, I'll briefly mention the happy fact that I yesterday went on my first outdoor climb for a while, up the Balmflue south ridge, a nice long route of 16 rope lengths in the Swiss Jura hills close to... Read more →

IFC Exporter Open Source Wiki

As you certainly know, the Revit IFC exporter is open source and available from the sourceforge IFC Exporter for Revit project repository. It has now been updated to Revit 2015, obviously, covers import as well as export, and enhanced with a FAQ wiki to address the most frequently asked questions. Below, I would like to present both the main IFC exporter project description and its new FAQ. Autodesk Revit Wikipedia Entry Before getting to that, let me briefly add that... Read more →

Element Id – Export, Unique, Navisworks and Other Ids

Here are a couple of discussions on the topic of Revit element ids, unique ids, and export ids. Some have been hanging around for a while, while others are more recent. We already looked at some aspects of this in the discussion on IFC GUID generation. Let's go through another iteration now: Unique Id versus ElementId to store in external database Local Uniqueness of the Revit Unique Id Navisworks versus Revit Object Unique Ids Negative element ids and property drop-down... Read more →

More on Revit API Aspects and Features

Yesterday, I mentioned a couple of Revit API aspects and features that triggered follow-up comments. Seeing as the topic appears to be of general interest, let's pick them up and continue this. I'll add a few other little titbits first, as well, though, related to meat, BIM, and the Revit API, in that order: Help escape the Meatrix Autodesk BIM interoperability landing page BIM acronyms and dictionary Creating non-rectangular openings in walls Reactions on the Revit API abomination Help Escape... Read more →

Texture Bitmap and UV Coordinates

Yesterday, I mentioned the new custom exporter framework providing direct access to the Revit viewing and rendering graphics pipeline. That brings new possibilities to a related area that we discussed way back in 2010: how to obtain texture data UV coordinates. At the time, the Revit API did not provide this information, and a work-around based on the Revit FBX export helped a little. Happily, the custom exporter framework opens that up a bit more. Let us look at that... Read more →

IFC Export Area Calculation and Other Enhancements

Here is a typical question that may arise when working with IFC export and shows the importance of the extension possibilities provided by the IFC export open source project: Question: How are the areas and volumes of walls, rooms, floors, etc. calculated for the IFC export? Are any standards being used? Some examples of values and parameters in question when we export IFC files from Revit: For rooms IfcSpace under BaseQuantities: GrossFloorArea, NetFloorArea; these values are the same in my... Read more →

IFC GUID Generation and Uniqueness

We looked at IFC GUIDs a couple of times already, e.g. to discuss the relationship between UniqueId, DWF and IFC GUID, the ExportUtils.GetExportId method, and the IFC GUID representation algorithm. The Revit 2012 API introduced the ExporterIFCUtils class for customizing IFC export, and the IFC exporter was released as open source. In Revit 2013, the IFC export implementation switched to a more generic toolkit, many of the APIs introduced in Revit 2012 were removed and replaced, and new interfaces introduced... Read more →

Graphically Display Area Boundary Loops

I recently worked on a case from a developer struggling with area boundary loops and attempting to determine whether they were closed or not by looking at the coordinate values in RevitLookup. I hold that the average human brain is overtaxed by trying to analyse graphics manually, or rather, cerebrally. I therefore implemented a sample command DisplayBoundary to display them graphically instead. It iterates over the boundary segments of selected areas, or all areas in the model, and creates a... Read more →

DevCamp Day Two

This morning I presented my second session, on some of the Revit 2013 UI API enhancements, in the Revit API beginner track. After that, I returned back to the Revit API expert one to attend the presentations on modeless interaction and IFC before presenting my final session on the Revit MEP API. Here then are my sessions of today, in chronological order: 1-4 Revit 2013 UI API enhancements 2-3 Asynchronous interactions 2-2 IFC export open source 2-7 Revit MEP API... Read more →

Revit IFC Exporter Released as Open Source

In June, Autodesk released the Revit STL exporter as open source. Now we are kicking of another even more exciting new open source project, really hot news for all Revit developers, especially if you are interested in IFC. Before we get to that, here is another little snippet on my weekend activities. Clariden Mountain I spent last Saturday in the Swiss Alps, climbing the Clariden Mountain with my friend Martin. It was not really a climb, just a hike up... Read more →