Revit versions 2023 up to 2024.2 (I don’t have anything newer)
The family uses the concave arc length of a specified circle as part of the revolve shape.
When you attempt to pull the geometry into the Dynamo environment, the resulting solid seems to be taking the convex arc length instead, giving you a much, much larger form.
Not my family file (this is from the Autodesk forums), but this is reproducible with a simplified family file.
Is there an alternate method of getting the solid geometry here?
Shameless bump for visibility.
Is this just a general issue with revolved forms? Would it be more practical to use a non-Revolve method and approximate the geometry for compatibility purposes?
Depends - what is the use case for the geometry in Dynamo?
1 Like
Wow I posted this a long time ago.
I didn’t know what the original autodesk forum poster’s use case was and so neglected to comment, but as luck would have it this happened to come up again while I was working on a campus line-of-sight equipment visualization script.
In my particular case, the script takes the rotation-corrected bounding box of mechanical equipment, and collects test points along the top surface perimeter. It later uses these points against a similar collection of edge points around the roof and does simplified projection down to a test surface (end result is a plan view region that describes the portion of the site where no equipment can be seen).
It worked well on basic equipment types - packaged RTUs (rectangular cuboids), roof fans (domes), and small unitary equipment. Where it started to fail was with manufacturer-supplied VRF heat pump families - they use sweeps to model the concave shape of the condenser fans on top.
When pulling the geometry into Dynamo, rather than get what should be a yo-yo shape on its side, the sweep is somehow split in half and creates two toruses that extend far beyond the equipment. Unless I can somehow exclude or reconcile this type of geometry, the BoundingBox is no longer an accurate representation of the equipment.
Think you’ll have to shift to a Revit API solution, pulling the bounding box of the family type and transform that by the coordinate system of the instance.
