The Building Coder

Re-Researching Lighting Family Instance Placement

The placement of family instances can sometimes be a tricky topic in the Revit API. Programmatically, this is always achieved using the NewFamilyInstance method. However, this method provides 13 different overloads to choose from, which can be a non-trivial task: NewFamilyInstance(Face, Line, FamilySymbol) – Inserts a new instance of a family onto a face of an existing element, using a line on that face for its position, and a type/symbol. NewFamilyInstance(Line, FamilySymbol, View) – Add a line based detail family... 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 →

Calculating Gross and Net Wall Areas

Determination of gross and net areas and volumes is fundamental to BIM. Here is an interesting solution to determine the gross and net area of a wall, i.e. with and without its openings, making use of the SpatialElementGeometryCalculator and the temporary transaction trick. The question was raised and solved by Phillip Miller of Kiwi Codes Solutions Ltd, starting with the Revit API discussion forum thread on door/window areas: Question: I need to determine the cut areas of windows and doors... Read more →

Family Instance Area and Auto-Loading a Project File

I have been pretty busy answering queries on the Revit API discussion forum in the last few days. Here are two that I quite like that came up today, on calculating areas occupied by furniture and equipment family instances and loading a project file automatically on Revit start-up. Calculating Areas Occupied by Furniture and Equipment Family Instances This query was raised by Vyom Dixit on how to calculate model group elements area: Question: I am new to the Revit API.... 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 →

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 →

Attached Detail Groups and Inverse Relationships

I am still at the Berlin hackathon, working with the MovieMemory team... In between other tasks, let me mention the interesting discussion and solution by Revitalizer on the Revit API discussion forum to check for attached detail groups: Question: Can someone tell me, please, how I can find out if a Group (Type) has an Attached Detail Group (Type) via the API? Answer: A group of category OST_IOSAttachedDetailGroups has a BuiltInParameter.GROUP_ATTACHED_PARENT_NAME. This way, you will find matching Model groups. Response:... Read more →

Autodesk View and Data API Webinar

I listed a whole bunch of upcoming events last week. Now I have yet another one to announce, a webinar introducing the Autodesk View and Data API, immediately preceding the exchange apps hackathon. Autodesk Exchange Apps Hackathon – September 20-21, 2014 There are less than two weeks left before the Autodesk Exchange Apps Hackathon, a two-day virtual web based coding 'festival' that will run from September 20 through to September 21, 2014. This year's event is bigger and better than... Read more →

Exploring How to Remove a Shared Parameter Definition

Here is yet another example of the importance of the RevitLookup database exploration tool. In this case, Trevor Taylor of ZGF, Zimmer Gunsul Frasca Architects LLP, shows his use of it to discover how to remove a shared parameter definition. Task at Hand When I remove a shared parameter definition, it disappears from the UI. However, the parameter definition isn't truly removed from the model. Its definition persists. Steps to repeat: In a shared parameter definition file, create a parameter... Read more →

Setting the Phase of a View

Here is a quick summary of one of the many issues being discussed on the Revit API forum, on changing the phase of a view, with a quick and happy conclusive result: Question: Is it possible to change the phase of a view? Something like view.phase? I've tried with the created phase but it doesn't work. Thank for your help! Answer: Does this old discussion on creating a room on a level in a phase help? Please look specifically at... 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 →

AdnRme Migrated to Revit MEP 2015 on GitHub

John asked a very relevant question in a comment on the Revit 2015 Update Release 3 that prompted me to complete the rather overdue migration of the ADN Revit MEP sample add-in AdnRme to Revit MEP 2015. I also took this opportunity to create a GitHub repository for it: AdnRme GitHub repository Revit MEP 2014 version 2014.0.0.1 Revit MEP 2015 version 2015.0.0.1 Much easier to share and collaborate on. The enhanced documentation now explains all the basics and points to... 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 →

Project Solon and BipChecker for Revit 2015 on GitHub

One of the handful of Revit database exploration tools that I use on a regular basis is BipChecker, the Revit built-in parameter checker, so that is a pretty obvious candidate for migration to Revit 2015... see below. Before I get to that, let me mention some new Revit energy analysis functionality that you might want to check out: Simple Interactive Energy Analysis in Revit with Project Solon Project Solon beta arrives in Revit, providing more interactive energy analysis results, the... Read more →

Category Support for Shared Type and Instance Parameters

Welcome to my last post on the Revit 2014 API, and one final new external command and update of The Building Coder sample collection before we migrate to Revit 2015. Revit 2015 was released last week, the Revit SDK was posted and updated, RevitLookup for Revit 2015 is available on GitHub and the DevDays Online presentation on the new API functionality is available. Before migrating The Building Coder samples from Revit 2014 to Revit 2015, let's add one last external... Read more →

Cannot Get BindingMap of a Family Document

Here is an issue trying to access the binding map of a family document that just re-arose as a new ADN support case. It took me a while (thank you, Google) to discover that I had actually already answered the very same issue in the past in the Revit API forum discussion thread cannot get binding map of a family document error 2014. Therefore, I think it is best for both you and me if I promote it to a... Read more →

Detach Beam from Plane

Here is a long-standing question raised once again now by Miroslav Schonauer of Autodesk Consulting and solved with help from Sasha Crotty of the Revit development team: Question: Is there a way to programmatically replicate the 'Detach from Plane' functionality accessible in the user interface through the beam context menu? I can right click on a structural beam and select 'Detach from Plane'. Revit removes the parameter 'Work plane', i.e. BuiltInParameter.SKETCH_PLANE_PARAM, and enables the 'Reference Level' parameter, which is read-only... Read more →

Creating an Offset Wall Solution

Happy St. Valentine's Day! As we all know and have known for a long time from the exploration of the wall compound layers, the Revit API wall location line is at the centre of the wall. There is no way to change that, and it is important to note that the API location line is completely separate from the one whose location can be controlled through the user interface, and also through the built-in parameter WALL_KEY_REF_PARAM, but only after the... Read more →

Deleting Unnamed Non-Hosting Reference Planes

Once upon a time, while teaching a Revit API class, the training participants identified a problem that was simple enough to be used as a filtered element collector learning example and did something useful at the same time: deleting reference planes not hosting any elements, implemented as the stand-alone external command DeleteUnnamedNonHostingReferencePlanes. It deletes all reference planes that have not been named and are not hosting any elements. Here is another thread discussing filtering reference planes and explaining the use... Read more →

The GEOM_VISIBILITY_PARAM Visibility Settings

Here is an nice, useful and interesting example of a Revit API forum discussion thread and cooperative research between Remy van den Bor of ICN Solutions, Rudolf Honke of Mensch und Maschine acadGraph, the Revit development team, Joe Ye and your humble scribe on retrieving an element's detail view visibility settings, before wishing you and us all the best for the year of the horse: Remy: Hello Reviteers, Does anybody know how to get to the visibility settings in the... Read more →

Final Rolling Offset Using Pipe.Create

I am writing this on the way back to Switzerland from my hiking trip on La Palma. Actually, lacking good bandwidth during my travels, I actually arrived back before being able to post this... Even before my return, I already have some good news to share: Victor Chekalin provided a working sample of using the static Pipe.Create method, so I can update my rolling offset series to make use of that more modern and flexible method rather than the older... Read more →

Determining Whether Parameter is Type or Instance Bound

Here is a question that came up now and then in the past, on how to determine whether a given parameter retrieved from the document shared parameter bindings is bound to a type or instances. Question: I have not been able to find a way in which to determine if a parameter is a type or instance in the Revit API. The only reference I could find was to the FamilyParameter.IsInstance property. However, this only works if you are in... Read more →

Translated Shared Parameter GUID Consolidation

Obviously, a language independent application is much easier to implement and maintain than a language dependent one, once you have the internationalisation framework for it in place. By the way, I took this opportunity to add the new category I18n to this blog to collect these kind of topics. The Revit API offers support for creating language independent add-ins, e.g. by using the built-in parameter and category enumeration values instead of localised strings. For the inverse operation, the LabelUtils and... Read more →

Max' Revision Wrapper Class

Max posted a comment on what's new in the Revit 2014 API presenting a neat little revision parameter wrapper class that I have taken the liberty of adding to The Building Coder sample collection. In Max' own words: For everyone also looking for the Revision parameters: Here a little wrapper class in C#: using System; using Autodesk.Revit.DB; namespace BuildingCoder { ///

/// A Revision parameter wrapper class by Max. ///

class JtRevision { ///

/// The BIM... Read more →

10.000.000.000th Post and Element Type Parameters

This is the 1024th post on The Building Coder, just to top off our recent 5-year and 1000th post celebration. The decimal number 1024 equals 2^10, i.e. 10.000.000.000 in binary format, hence the large number of zeroes in the title :-) I am also still away on vacation and this is the second post in my absence – or 10th, in binary format :-) – dealing with retrieving ElementType parameters, the ADN Xtra labs built-in parameter checker and a BipChecker... Read more →

Creating an Offset Wall

Here is an issue we have not looked at in a long time, brought up again by the following query: Question: I am creating a tool to generate a BIM from CAD data. One of the steps involves generating a floor slab, and then placing exterior walls along its edge. The tool begins by using model lines and arcs as a profile to generate the floor. Unfortunately, that generates walls that resting half on and half off the slab: How... Read more →

Determining Maximal Flow in HVAC Duct Connectors

A colleague came up with a request for a simple Revit MEP HVAC utility add-in that I would like to present. Question: We need to extract some specific ductwork values in Revit MEP and report them to the user. To begin with, all we need is the largest flow value on each duct, exported to a shared parameter on the duct. The purpose of the routine is for the users to confirm their duct sizing with this data reflecting the... Read more →

View Filter API

One long-standing developer wish list item that was fulfilled by the Revit 2014 API is the ability to access, add and control the view filters listed in the visibility dialogue. The Revit API now provides the following methods supporting this: View.AddFilter() View.SetFilterVisibility() View.SetFilterOverrides() Here are several variations of the request for this functionality that help understand the need and new possibilities by highlighting the numerous ways in which it can be used: Question 1: We want to programmatically achieve what... Read more →

Family API – Nested Type, Instance and Symbol Retrieval

Welcome to the third and final part of the detailed discussion on use of the Family API in the project environment, covering scenario 3 and the remainder from the following list of topics: Family editor product functionality Key family concepts Building your first parametric Revit family Slide deck bullets Complete slide decks Family API topics API scenario 1 – load family and place instances Checking whether a family is loaded Find a database element by type and name Loading a... Read more →

Migrating a Built-in Category and Other Things

Here is a category related issue that appeared when migrating from the Revit 2013 to the Revit 2014 API, plus a several other typical simple little Revit API questions from the last day or two: Migrating the room separation lines built-in category Storage of RGB colour values for materials Updating a DXF link Retrieving truss family elements Retrieving stair stringer data Storing custom data Migrating the Room Separation Lines Built-in Category Question: I get the following error while migrating my... Read more →

Changing a Family Parameter from Type to Instance

Here is a short and simple question that just cropped up and required some digging around until my colleague Phil Xia came up with the right answer: Question: Is it possible to change the type of a family parameter programmatically? This is possible in the family editor. I only see the IsInstance property, though, and it is read-only. I could achieve the same effect by deleting the parameter and creating a new one. Obviously that would require updating all the... Read more →

Parameter DisplayUnitType, Bretagne and Decompilers

After looking at several performance enhancement possibilities last week, e.g. the sweep family performance enhancement and LoadFamily and collector iteration performance, here is another exciting and pretty sophisticated exploration of internal Revit API implementation details by Victor Chekalin that can be used to achieve a significant speed improvement when accessing large numbers of parameters and checking their DisplayUnitType property. Brittany Before getting to that, though, here is an update on my current whereabouts. Yesterday I spent travelling to Brest and... Read more →

Units and RevitLookup

Here is a typical question from a Revit API newbie that prompts me to reiterate some important basic beginner information on units and the RevitLookup tool for exploring the Revit database: Question: How can I retrieve the length and mass units from a Revit document? Answer: The internal Revit database length unit is always imperial feet. That cannot be changed, so there is you answer for that. Similarly, the internal database unit for weight is kg, as far as I... Read more →

Content Localisation

How to manage families and content creation is a crucial topic for a large number of Revit add-ins. Brian Johnson, technical specialist on structural engineering solutions at Autodesk in Austin, Texas, discusses how to efficiently address some important aspects of this below. First, however, let me wish everybody a Happy New Year of the Snake! A year for reflection, planning and searching answers. A good time for shrewd dealings, political affairs and coups d'état. People will be more likely to... Read more →

Parameters versus Properties

In his comment on reading material asset data, Alexander Buschmann points out that this same information can be accessed without retrieving, reading and converting the data directly from the undocumented built-in parameters. Instead and more comfortably, you can use the following official properties on the appropriate classes: Material material = null; foreach( Material mat in e.Materials ) { material = mat; break; } PropertySetElement pse = doc.GetElement( material.StructuralAssetId ) as PropertySetElement; StructuralAsset asset = pse.GetStructuralAsset(); double a = asset.WoodBendingStrength; double... Read more →

Change Element Workset

We discussed reading the workset of an element, either using the built-in parameter ELEM_PARTITION_PARAM or, more easily, the dedicated document GetWorksetId method. This is actually another example of the possibility to choose your data access method by using either a dedicated property or a parameter, as we recently explored to achieve changing the viewport type. Although the Revit API provides a dedicated property to read an element workset, it does not do so for changing it, which begs the question:... Read more →

Read Material Asset Parameter

Even though it is still January, the days are already getting a little bit lighter, the sun has broken through now and then, sets half an hour later, some birds are starting to tweet around, and one can imagine spring coming... Meanwhile, in the Revit API, accessing materials tends to be tricky, so here is one little sample that hopefully helps clarify by demonstrating how to read a parameter value from a PropertySetElement attached to a physical material asset. Question:... Read more →

Duplicate Built-in Parameter Values and BipChecker Update

BipChecker is a tool that I would recommend every Revit developer to install, just like RevitLookup. It simply lists the values of all parameter data stored on a selected element. Similar access is also offered within RevitLookup by the option Parameters > Built-in Enums Snoop... BipChecker offers much more functionality, though, and is a really powerful Revit database exploration and debugging tool. The built-in parameter checker has been part of the ADN sample labs for ages now, and the original... Read more →

Changing Viewport Type

Here is a question on setting the type of an element by using the built-in ELEM_FAMILY_AND_TYPE_PARAM parameter value, explored by Bettina Zimmermann of NTI Cadcenter A/S: Question: I'm inserting viewports on sheets and I'd like to change the viewport type to my own defined type. How can I this programmatically? By default, the API call creates a new viewport with type "Title w Line". I'd like to change that to e.g. my own type "Test". Here is my own self-defined... Read more →

Revit 2013 Unit Conversion Utility

Here is a Revit 2013 update of the Revit 2011 unit conversion utility, originally posted and described for Revit 2010, by Harry Mattison. In his own words: I was looking at the great unit conversion utility and created a new version upgraded to Revit 2013 that I thought you readers might enjoy. I ran into one issue that required a code enhancement to catch an exception thrown by many parameters, such as HVAC_Temperature, HVAC_Slope, etc. The rest of the code... 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 →

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 →

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 →

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 →

Group My Own Commands in the Ribbon

Here is an issue that has been presented numerous times in the past, and apparently needs to be highlighted again for newbies. Question: I have implemented a Revit add-in which implements several commands. Currently, I have added all my commands to the add-in manifest file, as recommended by various examples I found on the Internet. It works and they do indeed appear in the Add-Ins ribbon tab under the 'External Tools' pull-down menu. The problem with this is that other... Read more →

ADSK File Import and Phase of Room

I already had one look at loading an Inventor ADSK component using the OpenBuildingComponentDocument method. Ishwar Nagwani of Autodesk Consulting now revisited this topic from a different perspective and explains: I came across another tricky issue while developing Revit add-in to import an ADSK file. I looked at your previous post on this when I started looking for way to open ADSK file in Revit and it helped me lot. The ADSK file is created in Inventor and then processed... Read more →

Change Section View Type and Hide Cut Line

Leo raised a couple of questions on section view creation in his comment which Rudolf Honke very kindly answers thus: 1. Hide view: To hide the cutting line in a plan view, you can use this parameter: viewSection.get_Parameter( BuiltInParameter .SECTION_COARSER_SCALE_PULLDOWN_METRIC ) .Set( 1 ); 2. Generate section view: In Revit 2013, you can use the static method public static ViewSection CreateSection( Document document, ElementId viewFamilyTypeId, BoundingBoxXYZ sectionBox ) In Revit 2012, you can use document.Create.NewViewSection( BoundingBoxXYZ ); 3. Change the... Read more →

Create a Pipe Cap

Happily mixing the different Revit versions, let me follow up my work on the Revit MEP 2013 API and the updated AdnRme sample by another MEP related topic. Before getting to that, though, here is a brief heads-up for a new technology preview on Autodesk Labs: BIM Coordinator The effective organization of project data in shared or related coordinates is essential to effective collaboration across disciplines and good quality project information. BIM Coordinator for AutoCAD Civil 3D and Revit is... Read more →

The ADN MEP Sample AdnRme for Revit MEP 2013

Yesterday I discussed the Revit 2013 MEP API and the external services framework. In preparation for my Revit MEP API presentation at the upcoming AEC DevCamp in Boston in June, I also migrated the ADN MEP API sample AdnRme to Revit MEP 2013. The initial flat migration was extremely straightforward with zero code changes required. I obviously had to change the Revit API assembly references, which forces an update of the .NET framework version to 4.0. After bumping the framework... Read more →