The Building Coder

Picked Instance Face Geometry in LCS Versus WCS

Depending on circumstances, interactively picked family instance geometry may be returned in the global Revit world coordinate system WCS, or in the family instance definition local coordinate system LCS. A family instance may have its own non-empty solid, or use the symbol geometry. The symbol geometry requires keeping track of the instance transform to map it to the actual instance project location – Question on Incorrect Face Normal – Working Plane has no Effect – Non-Picked Face Normals are Correct – Solution – Detecting When to Use LCS versus WCS – Retrieval of Picked Geometry Face from Instance is Untransformed... 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 →

FindInserts Determines Void Instances Cutting Floor

Here is another brilliant and super succinct solution provided by Fair59, answering the Revit API discussion forum thread on how to get cutting void instances in the floor using the HostObject FindInserts method – Question: I have a floor on which a family instance is inserted on the face of the floor (the instance host is also the floor). I checked in the family the "Cut with Void When Loaded" parameter, so that the void is created in the floor. Now, I want to retrieve all the instances that create voids in the floor... Read more →

Determining RVT File Version Using Python

We discussed several approaches to read the BasicFileInfo and RVT OLE storage, aka COM Structured Storage, to retrieve stuff like the file version and preview image, and, more lately, alternative access to BIM data via Forge... Read more →

Finding an Exit Path and ElementId Parameter Values

As usual, lots of exciting discussions are being conducted in the Revit API discussion forum. I'll just highlight two of them going on right now – Finding a path through the BIM – Finding all possible ElementId values for specific Parameter... Read more →

Determining Dimension Segment Endoints

A rather hard struggle led to a rather simple solution for determining the start and end points of dimension segments. In summary, the solution looks like this – A Dimension element is either single- or multi-segment; these two cases need to be handled separately – In case of a single segment, the dimension element itself has a line, an origin and a value; the line is indeed the dimension line. However, it may be unbounded... Read more →

Handling Third Party Library DLL Conflicts

A recurring question just came up again, on handling conflicts between DLLs loaded by Revit add-ins. For instance, this can be caused by a scenario in which add-ins A and B both make use of library DLL C, but specify different versions. A soon as the first add-in has loaded its version of C, the second add-in is prevented from loading the version it requires and cannot run... Read more →

Aligning a Slightly Off-Axis Grid

Here is a follow-up on the recent discussion on how to modify a grid curve end point using Grid.SetCurveInView. In the Revit API discussion forum thread on off-axis grids causing warnings in Revit, an attempt to use the same approach fails. Instead, Fair59 presents a solution using RotateElement to align an almost horizontal or almost vertical grid that is slightly off-axis... Read more →

Hatch Line Dimensioning Voodoo

Reporting on a very exciting topic from the Revit API discussion forum from the Forge accelerator in Barcelona – Barcelona Forge accelerator – Retain the Add-In GUID – Dimension on hatch pattern... Read more →

Sensors, BIM, AI, RevitLookup, Fuzzy Comparison

We continue patrolling the well-trodden paths of BIM, AI, Revit precision and RevitLookup – Connected BIM – Intuitive AI – Fuzzy Comparison – RevitLookup 2018.0.0.1... Read more →

AI News and Sub-Transaction Regen

Things continue moving fast in AI, and the need to regenerate in the Revit API remains unchanged – AI News – Subtransaction Requires Regeneration... Read more →