Intersecting Elliptical Vault Ceiling

Yesterday, I read the news (oh boy) about a lucky man who made the grade…

Photos of the “Italianate villa” showed rooms with intersecting vaulted ceilings that inspired a GH quest:

My first effort used mirrored BiArc curves that worked fairly well but could produce wiggly lines at the intersections, depending on parameters. So today I tried half ellipses instead and discovered magic! With ellipses, the diagonal intersections in top view are always straight lines. This is wonderful!! The X and Y arches can have different widths but all have the same height.

These are the inputs:


“gap” is the dimension of square columns, not included in the model though easily could be:

Kind cool, eh? (35.1 KB) (fixed divide-by-two error in ‘height’)

P.S. Here is the BiArc version, deprecated: (33.2 KB)


As a cross reference to a recent thread, this simplified version should be considered: (19.3 KB) (20.8 KB)


Inspired by a recent thread, I developed a pEllipse cluster to create “pointed ellipse” curves. It took some hacking to make it a “well behaved”(?) drop-in replacement for the standard Ellipse component. (35.4 KB)

pointed_arch_2022Sep24b (18.0 KB)