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By Lingwisyer
#324093
Just curious, how would you actually build an elliptical arch?

Also, I believe the Ellipse Top Window Opening object is a three point arch given the math, so no actually and ellipse...



Ling.
By mbl
#324112
As far as I know, it's also not possible to make an elliptical hole in a slab for example ... or basically any 3D Element of elliptical shape.

So I guess Archicad doesn't really like ellipses other than in 2D.
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By borgo1971
#324120
Lingwisyer wrote: Mon Mar 29, 2021 3:16 am Just curious, how would you actually build an elliptical arch?
Do you mean in construction?
Its pretty simple... you start with the two focal points at stills bundled with a taut string. Then start nearing the focal points and elevating the center of the string until you reach the desired arc height and you fix the focal points. After that you take a pencil and holding the string taut with it, you can draw the elliptical arc.
Last edited by borgo1971 on Thu Apr 01, 2021 6:05 pm, edited 2 times in total.
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By borgo1971
#324121
mbl wrote: Mon Mar 29, 2021 3:36 pmSo I guess Archicad doesn't really like ellipses other than in 2D.
In GDL you can create solid ellipse stretching a cylinder with MUL command. And there is an ELLIPS command for hemisphere ellipsoid (but this could be less suitable). But I guess the more feasible option is to calculate mathematically the coordinates of the points that approximate the elliptical arc based on the resolution parameter.