The Building Coder

Aborting Filtered Element Collection

I just discovered an interesting and not completely obvious aspect of using a filtered element collector in the Revit API discussion forum thread on aborting a long running filtered element collector. Question: I have really large models where I use an ElementIntersectsElementFilter that can take a long time to process, and sometimes I want to abort it in a graceful way. Is this possible? Read more →

Purge Unused using Performance Adviser

Matt Taylor of WSP shares a solution to Purge Unused using the Performance Adviser – PurgeTool.vb implements GetPurgeableElements – PurgeUnused.vb external command... Read more →

Colleagues Deleting Non-Shared Project Parameter

Some happy news about two new Revit API supporter colleagues, Naveen Kumar and Zhong Wu. They already reached second and third place in the list of top solution providers. Here is also a very relevant recent case handled by Zhong – Top solution authors – Naveen on Naveen – Zhong shifts to AEC – Zhong on Zhong – Deleting a non-shared project parameter... Read more →

REX SDK Templates for Revit Structure 2019

Apparently, the Revit SDK REX Visual Studio templates are obsolete. Let's fix that problem. Also, two little notes on a C# optimisation trick for math-heavy code, and the current status of the Forge Design Automation API for Revit – Revit Structure 2019 REX Extension SDK Visual Studio Templates – Improve C# Performance Using Struct Instead of Class – Update on the Forge Design Automation API for Revit... Read more →

Forge Tutorials and Filtering for a Parameter Value

Today, let's revisit the topic of filtering for a parameter value, and mention the updated Forge tutorials – Learning Forge tutorials – Filtering for a specific parameter value – Filtered element collector optimisation... Read more →

Create 2D Arc and Filter for Intersecting Elements

Several questions on filtering for intersecting elements came up recently. It is pretty easy as long as a bounding box can be used. However, the bounding box is generally aligned with the cardinal X, Y and Z axes. If the containing volume of interest is not, too many elements may be selected – Family instances in a diagonal room – Conduits intersecting a junction box – Generate 2D arc from radius, start and end points... Read more →

Efficiently Retrieve Crop Box for Given View

Konrads Samulis shared a very nice solution to retrieve the crop box for a given view using a highly efficient parameter filter in his comment on rotating a plan view. In digging up this old thread, I found something quite curious in the API in 18.1, that I'm not sure was there before. The method of using a temporary transaction (with rollback) to find the element id of the crop box was taking a very long time on a large model, so I did a bit of digging to see how I could improve it. I noticed that in the built-in parameter ID_PARAM of the crop box contains the element id of the view it's in. E.g., the crop box 'points' to the id of the view it is in using ID_PARAM... Read more →

Forge, Installed Version, Move Group, Name Filter

A biggish post rather late in the week... still answering too many cases – Forge for AEC demos and sample code – Determining the starting view – Detecting installed Revit version – Detecting installed C3D version – Moving items inside a detail group – Filtering for family instances and types by family name... Read more →

Retrieving Elements Visible in View

Minho re-opened the Revit API discussion forum thread on getting the ElementId of all visible entities in a viewport, providing a good opportunity to mention Colin Stark's answer to the StackOverflow thread on determining whether a FamilyInstance is visible in a View. Question: I am looking for code to get the ElementIds of all entities inside a viewport. A viewport is a region of a big view plan... Read more →

Revit Future Direction and Public Roadmap

Here I am in Munich, supporting the one-week Forge accelerator workshop – Pizza and Isar – Public Revit Roadmap – Revit Idea Station – Revit Today and Tomorrow... Read more →

Avoid CAD Import in RFA, AAG16 and Endtrip

Some interesting topics of the day for this first cloudy one after a truly wonderful Indian summer – Avoid imported CAD content in RFA family definitions – Advances in Architectural Geometry 2016 – Endtrip full sound replacement... Read more →

Implementing the TrackChangesCloud External Event

Today, I'll discuss this morning's work – TrackChanges enhancement idea – The TrackChangesCloud add-in – The TrackChangesCloud external event – Creating and raising an external event – Raising the external event from a separate thread – First test run – Trigger immediate execution by setting Revit foreground window – Complete external application module – Next steps – Download... Read more →

API, SDK and View Section Box Element Intersection

Trying to keep track of the overwhelming information flow provided by the numerous discussions on the Revit API discussion forum is impossible. Here are two little titbits from the past few days – Basic Revit API and SDK Access, Online and Offline – Filtering for Elements Intersecting a View Section Box... Read more →

EstoreFile, Group Preview and RoomScheduleCloud

Lots of exciting topics for today – EstoreFile, extensible storage and embedding a raster image – Preview Image for a Group – Thoughts on migrating the Room Schedule sample to 64-bit: Request, Implementation suggestion, Problem, Response – Autodesk 2016 AEC showreel call for submissions... Read more →

Tracking Element Modification

How to determine and track element modification? I implemented a solution! – Two approaches – Task analysis – Modification tracker – Creating an element state snapshot – Determining which elements to track – Implementation – Geometrical comparison – String formatting – Retrieve solid vertices – GetTrackedElements – retrieve elements of interest – GetElementState – store element state – Creating a database state snapshot – Report differences – External command mainline Execute method – Sample runs – Demo recording – Download... Read more →

Idling, DMU, DocumentChanged and Need for Regen

Today we have two ever-recurring topics to revisit: a discussion on how to react to a document modification and yet another example of the need for regeneration – Idling and external events, DMU and DocumentChanged – Need for regen in an updater... Read more →

Retrieving Wall Openings and Sorting Points

I continue my rather active involvement in the Revit API discussion forum. Lets look at one of them, and an associated point or two – Retrieving wall openings – Ray shooting solution – CmdWallOpenings implementation – Faster lexicographical point sorting... Read more →

Quick, Slow and LINQ Element Filtering

I arrived back safe and sound in Switzerland after the exciting week at Autodesk University. Another happy arrival is my first grandson: He was preceded by his big sister almost two years ago. Life goes on. I have been wanting to highlight the difference between quick and slow element filters for quite a while, and now a query came in that provides an ideal opportunity – Use of LINQ with filtered element collectors – Revit element filter classification – Filter types – Efficiency guidelines – Logical filters – Quick filters – Slow filters... Read more →

Change Type, Iterate Elements, Create Family

Let's wrap up this hectic week with a couple more recently answered issues and one non-Revit note – Changing element type – Iterating over elements – Creating an electrical family – La costola di Adamo... Read more →

DirectShape From Face and Sketch Plane Reuse

The creation of a DirectShape element on an interactively selected existing element face requires a transformation to be applied to the face of a family instance returned by the PickObject method to convert it from the family symbol space to the family instance real world coordinates – Creating DirectShape from face mesh – Determining real world transform of a family instance face returned by PickObject – Iterating over element geometry to find a specific target geometry object – Reusing sketch planes for model curve creation... Read more →

Revit Future and Saving User Configuration Settings

I encountered the need and implemented solutions to save user configuration data several times over in the past. Today, prompted by a recent query, I'll point out two of them, and some other exciting and interesting stuff as well: Anthony Hauck on Futures for Revit. The Most Popular Programming Languages 2015. Saving User Configuration Settings. Text Format Configuration File Storage and Parsing. .NET XML Configuration File Storage and Parsing. Anthony Hauck on Futures for Revit BIMThoughts is a podcast platform... Read more →

CopyElements, Revit 2016 Scalability, Python and Ruby

Here are a bunch of infos on and updates for Revit 2016, as well as some important hints on the use of the ElementTransformUtils.CopyElements method: CopyElements view argument is for 2D only Revit 2016 scalability enhancements Revit 2016 Python shell Revit 2016 Ruby shell RevitLookup for Revit 2016 CopyElements View Argument is for 2D only You should only use the ElementTransformUtils.CopyElements views argument when working with view dependent elements, i.e., 2D elements. This was pointed out by Arnošt Löbel in... Read more →

FindInserts Retrieves All Openings in All Wall Types

On Tuesday, I presented the new SpatialElementGeometryCalculator sample for calculating gross and net wall areas. It discusses a whole bunch of interesting aspects, e.g.: Use of the SpatialElementGeometryCalculator class. Porting a VB.NET Revit add-in to C#. Use of the temporary transaction trick. Use of filtered element collectors to determine all openings in a wall. Filtered element collector optimisation possibilities, e.g. integer instead of string comparison, use of a parameter filter instead of .NET post-processing. Vilo submitted a very relevant comment... Read more →

WebGL Goes Mobile and Sorted Level Retrieval

Today, let's look at a generic WebGL and a specialised Revit API issue: WebGL on all Apple platforms and sorted level retrieval. WebGL Goes Mobile Apple announced full support of WebGL for its desktop and mobile browsers, so WebGL goes truly cross platform, as pointed out by Paul Flanagan: Previous claims of cross-platform support for this HTML5 standard were largely worthless because they did not include the iPhone, iPad, or desktop Safari. That has changed, and this standard for 3D... Read more →

The Revit API is Never Ever Thread Safe

Let us summarise and preserve this interesting Revit API forum discussion between Erik Eriksson, Ollikat and Arnošt Löbel on why the Revit API cannot safely be used from multiple threads under any circumstances whatsoever, even for read-only operations: Question: I've been using the Revit API for some years now, but I have never tried multithreaded requests. Basically because Autodesk told me that it will never work. I've now grown a little more confident and started testing a bit. So I... Read more →

TessellateSolidOrShell – Holes Versus Wholes

Let's try to clarify further the various options to retrieve closed faceted shells from a Revit BIM. When processed face by face, the Revit API will return gaps. This issue was addressed by the introduction of the TessellateSolidOrShell method. Let's look at some pros and cons of it, raised by the Revit API discussion forum thread on mapping the triangles it generates to faces. We already looked at the topics of gaps in shells and the TessellateSolidOrShell method now and... Read more →

Views Displaying Given Element, SVG and NoSQL

I am slowly getting back to normal working mode after the AEC Hackathon last weekend and the neat project that we worked on there, so I finally get around to publishing this post that I started working on last week. The only remaining issue is of a physical nature: my feet are still swollen after flying to New York on Friday, sitting and working non-stop at the Hackathon from Saturday morning until Sunday afternoon, standing for a couple of hours... Read more →

DirectShape Performance and Minimum Size

One of the exciting API enhancements in Revit 2015 is the Import API functionality providing the new DirectShape and TessellatedShapeBuilder classes. These enable significant performance enhancements and powerful new possibilities for generating libraries and importing geometry, especially repetitive shapes. On the other hand, the same limitations on minimum size apply as in the past. DirectShape Performance Regarding the performance, here is a first enthusiastic reaction and quick report from a developer after the initial introduction during the beta phase last... Read more →

WPF Fill Pattern Viewer Control Benchmark

I recently presented Victor Chekalin's WPF control for viewing Revit fill patterns. In his comment, Victor already mentioned some worries about performance of this control and his intention to create a simple benchmark to monitor it. Well, here it is. At the same time, I also took the opportunity to migrate the fill pattern control to Revit 2015. Migrate the Fill Pattern Viewer Control to Revit 2015 The migration to the Revit 2015 API was extremely straightforward, just like the... Read more →

Profiling Revit Add-ins and RoomEditorApp Enhancements

Today we take a look a profiling tool that works with Revit add-ins, and a few small new enhancements to my RoomEditorApp. The entire following article was contributed by Ben Bishoff of Ideate Software: Profiling Revit Add-ins using GlowCode Performance profiling tools allow you to increase the speed of your code by pinpointing slow methods and methods that are called excessively. For the past several releases, we have successfully used GlowCode real-time performance profiler (www.glowcode.com) to analyse and improve the... 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 →

Lots of Views, Families and Booleans

Certain applications require large numbers of similar but different objects, e.g. for framing, scaffolding, steel detailing etc. Every one of the past few years, Revit has been further enhanced to better still support these kinds of applications and handle larger numbers of families and instances gracefully and performantly. This work is still on-going. Below, we address a bunch of questions related to creating a new wooden structural BIM application. One aspect of such applications is the need to generate a... Read more →

Triggering Immediate External Event Execution

We held our first West European Devday in Paris on Monday and I am now sitting in the airport headed for Milano. En route to Milano, I worked at testing Joe Ye's trick to trigger the Idling event (potential SetRaiseWithoutDelay workaround) to force an immediate execution of my external event. I also added a comment from Guy Robinson on Revit requiring focus that had me worried for a moment. However, the solution is easy! Before we get to that, here... Read more →

Replacing an Idling Event Handler by an External Event

I arrived back in Europe safe and sound from America. Healthy, as well, in spite of air conditioning and the freezing temperatures in some of the Autodesk University conference rooms. Thank God, I went well prepared with long-sleeved woollen underwear and thick heavy sweaters to face the arctic challenges of the desert town. As I hinted at when describing my last day at AU, I realised that I can significantly improve the implementation of the RoomEditorApp subscription to real-time database... Read more →

RoomEditorApp Idling and Benchmarking Timer

I solved my two RoomEditorApp Idling issues! They were especially worrying due to the fact that I am planning to present this application in my Autodesk university class DV1736 on Cloud-Based, Real-Time, Round-Trip, 2D Revit Model Editing on Any Mobile Device. By the way, you should now enrol in the AU classes you are interested in – unless you already did :-) Go to the AU class catalogue, sign in, click 'View All Classes', use the filters or keyword search... Read more →

The Dynamo Revit Unit Test Framework

I have repeatedly underlined the importance of unit testing, and recently presented the RvtUnit project enabling the use of the NUnit unit testing tool for Revit add-ins. The Dynamo team now presents another one; in case you have not already heard of and explored it, Dynamo is an exciting visual programming tool on top of Revit. The best explanation of Dynamo is provided in the Dynamo GitHub repository. Much of the discussion and suggestions for new features etc., is happening... Read more →

Load Your Own External Command on the Fly

How to reload an external Revit command without having to restart the Revit session has been a subject of discussion many times in the past, e.g. in reloading an add-in for debug without restart, which lists four possibilities: Set up Visual Studio to efficiently load the desired project and the debugee, use the standard cycle hitting F5 to start debugging, and stop debugging when you need to make code changes. Use the RevitRubyShell or RevitPythonShell to work interactively with the... Read more →

Filter for Family Instances in a Room

I wish you a Good Friday. Continuing the research and development for my cloud-based round-trip 2D Revit model editing project, I need to determine the boundary loop polygons to represent the furniture and equipment family instances for manipulation on the mobile device. Before I can start extracting their geometry, I need to access the objects themselves, i.e. determine which family instances are contained in the selected room. As always, we use a filtered element collector to access the Revit database... Read more →

Determining Purgeable Elements

A question that crops up from time to time and is rather hard to answer exactly and exhaustively is on purgeable elements: Question: What is the best way to get all of the elements that can be purged? I can use WhereElementIsElementType filter to return all types, and WhereElementISNotElementType to return instances, but comparing the two lists does not leave me with the purgeable result. I could compare individual lists of types (i.e. family symbol and family instance), but that... Read more →

LoadFamily and Collector Iteration Performance

Since we are into the topic of family loading performance anyway, after yesterdays discussion on efficient sweep creation, here is another interesting discussion with some useful family loading and symbol filtering benchmarking results and observations by Thomas Jarzyna and an in-depth analysis of the effects of converting a filtered element collector to a .NET collection by Scott Conover: Question: I need to load some family symbols into my project. I have a lot of different families and even more symbols,... Read more →

Sweep Family Performance Enhancement

Now I am back at work again, enjoying the queries coming in from developers, postponing other important things such as my own long-term class and presentation preparations etc. Addicted to helping, that's me. Anyway, here is a piece of doubly good news, in that the developers mentioned below did a good job of helping themselves, in addition to achieving a radical speed improvement from 40 hours down to 3 minutes, i.e. just 0.125% of the original time, to programmatically generate... Read more →

ToElementIds Performance

Conversion of a filtered element collector to an explicit .NET collection of elements or element ids is always costly and mostly avoidable and unnecessary. Before getting to the details of that issue, here is another quick snapshot from our travels to the West European developer conferences. As you either know or might guess, one of the main topics of these is cloud and mobile development, e.g. looking at topics such as the BIM 360 Glue REST API and SDK and... 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 →

FindElement and Collector Optimisation

As I recently mentioned, Mikako Harada published a very nice article on programmatically adjusting beam cutback. It was followed it up by a description of some commonly used helper methods to find certain named elements and family symbols in a project. One of them is FindElement, implemented as follows in that post: public static Element FindElement( Document doc, Type targetType, string targetName ) { // Get the elements of the given class FilteredElementCollector collector = new FilteredElementCollector( doc ); collector.WherePasses(... Read more →

FamilyParameter IsShared Property

A long time ago, we discussed a workaround to access the shared family parameter GUID using reflection, more specifically (and obviously) .NET Reflection. If you are new to this, here is an in-depth Code Project article on Reflection in .NET. Now Victor Chekalin, or Виктор Чекалин, ran into this issue as well and presents a much improved solution. Here is the background and our discussion on this: Question: Why does the FamilyParameter class have no IsShared Property, like the Parameter... Read more →

Exporting Parameter Data to Excel, and Re-importing

Did you observe the international talk like a pirate holiday yesterday? I did not, I'm sorry to say. I only became aware of it this morning trying to find some reason why it was so quiet yesterday. Aaarrr! Anyway, here is an update of an age-old sample application, originally created by Miroslav Schonauer for the very first Revit API training classes after the first introduction of the Revit API back in the Revit 2008 timeframe. Miro put together a whole... Read more →

DocumentChanged versus Dynamic Model Updater

Here is an interesting little overview and comparison of possibilities to react efficiently to the addition of certain elements to the database. Two easy ways to achieve this are by subscribing to the unspecific DocumentChanged event, or by registering a more specific DMU dynamic model updater. If you subscribe to an event or register an updater, it is also important to keep in mind to unsubscribe or unregister when you are done with it. We discussed both of these repeatedly... Read more →

Family Usage Filtered Element Collector Performance

Since all access to the Revit database and its elements takes place through the filtered element collectors, it is extremely important to make efficient use of them. We have not looked at that topic for quite a while now. Here is an issue that recently cropped up which illustrates some interesting points. I presented a filtered element sample for creating an XML family usage report which iterates over all the loaded families and launches a new filter for each of... Read more →

The Performance Adviser API

Unbelievable as it may seem, there are still a number of new areas of functionality added in the Revit 2012 API that we have not even got around to covering here yet at all. One of these is the performance adviser. Here is an article on that by my colleague Saikat Bhattacharya from the ADN AEC newsletter. The Performance Adviser API added in Revit 2012 allows developers to execute a set of built-in or custom rules against a given model,... Read more →

Timer Code for Benchmarking

Two topics today: Benchmarking add-ins Hands-on training Benchmarking Add-ins Just like most programming issues, many Revit API tasks can be achieved in numerous different ways. The optimal approach often depends on your individual needs. The only way to find out which one that may be is to test it. In order to test it effectively, you need to measure the results. One of the most important aspects is often the time required, the execution performance. Measuring a short duration of... Read more →