Approximate Ellipse to Arcs

Sharing this script which uses “French’s construction” to convert a Revit ellipse (drawn in plan) into four arcs which are cotangent at their end points:

Approximate Ellipse with Arcs.dyn (138.8 KB)

The resulting arcs can be used as a guide - via pick-lines - to draw walls (something not currently possible with Revit’s ellipse curves), or simply to provide a more rational shape for construction drawings (slab edges etc.)