Revit fails to handle indexed poly curve with ifc arc index
- Dominant language
- C#
- Stars
- 637
- Forks
- 225
- PR merge metrics
- No merged PRs in 30d
Description
A little digging in the arcs seem that Revit seems to glitch out when parsing geometry from arcs like this:
```
#16374=IFCCARTESIANPOINTLIST2D(((1010.,60.),(730.286976033,735.286976033),(55.,1015.)));
#16376=IFCINDEXEDPOLYCURVE(#16374,(IFCARCINDEX((1,2,3))),$);
```
I expect a quarter arc like that of a door swing, but I get funny arcs like shown below:

Contributor guide
Research direction
Start by reproducing the supplied IFC Cartesian point list and IFCINDEXEDPOLYCURVE with IFCARCINDEX in Revit, then trace the geometry parsing path for indexed poly curves and arcs. Compare the result with the expected quarter arc shown in the report; done means the example renders as the intended door-swing quarter arc without introducing incorrect curves.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- csharp
- Domain
- computer-graphics, desktop-dev
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Quiet
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100