Which method is used for 'Export rooms, spaces and areas as polylines'?

[loren_routh]

I am hoping to understand exactly how the .DWG export feature works when you check the box for 'Export rooms, spaces and areas as polylines'.

In the Area Class, there is:

• GetBoundarySegments(), which returns an array of 'segments'. 
• The Geometry property, which returns a solid object and also curves. 

It is my understanding that these are separate from AreaBoundaryLines, which can extend beyond the Area, overlap, etc., and does not reflect the true geometry of the Area.

None of these are polylines.  Is this something that isn't exposed (yet), or some other mechanism?

Why do I ask?  We have been having issues exporting AreaPlans where not every Area polyline comes through in the CAD drawing.  Strangely, the same AreaPlan will export fine in Revit 2021, but have missing Area polylines (with only the tag showing) in Revit 2023.   We use AreaPlans that consist solely of AreaBoundary Lines, no Walls at all.  This is on purpose (and another conversation).  Additionally, these exports contain Line geometry that I assume are the AreaBoundary model Lines.  They are not helpful and have to be removed.  These exports are used in an external process and must be either polylines or regions in CAD.  

Also, one of my goals is to use Area Gross Building geometry to create Generic Model extrusions that mimic the mass of the building envelope (by level).  For moderately complicated 2D geometry, I have yet to find a way to convert Areas (or Boundaries) into closed PolyCurves, Surfaces, or anything that can reliably be turned into a Generic Model Family object.

Could anyone give me some insight into this?

Thanks,

Loren

[jeremy_tammik · Accepted solution]

Use the Room or Space GetBoundarySegments method to retrieve the curve segment data and export that as you please::

• https://www.revitapidocs.com/2024/8e0919af-6172-9d16-26d2-268e42f7e936.htm

[loren_routh]

Yes, GetBoundarySegments does work. It gets the boundary segments. To get a closed polyline/polycurve that can be exported as .dwg or used in an extrusion, that is another matter. I will do a separate post for that. Thanks for clearing things up a bit.

[cmuldoonZMYQT]

Did you ever make that post about getting a .dwg of polylines?

[jeremy_tammik]

Here are some articles by The Building Coder that may help shed light:

• Revit 2014 API and Room Plan View Boundary Loops
• Determining Room Boundary Segment Generating Element
• Sending a Room Boundary to an SVG Node Web Server
• Room Boundaries to CSV and WPF Template
• AI, Boundaries, Loops and RevitApiDocs 2020
• Exterior Walls and Room Bounding Elements
• Exterior Walls and Room Bounding Elements
• Journal Magic, Adjacent Rooms and Room Boundary

[cmuldoonZMYQT]

Thank you.

[loren_routh]

Oh yeah! Check this out: https://forums.autodesk.com/t5/revit-api-forum/creating-a-generic-model-from-area-boundaries/m-p/123...