hallo at @pascal or all others:
what is the background of _sweep1 Framestyle = Freeform ?
(the option Framestyle = Roadlike is well explained in the help-files)
What is the background / how is the rotation of the cross curve defined - for Freestyle ?
I always thought, there is some relation between the unit tangent, normal and Bi-normal / osculating plane / Frenet-Serret-Frame.
But the following simple example doesn’t look like the the cross curves follows the osculating plane:
at the start the cross curve is parallel to the curve 's Normal, later it looks like a arbitrary Rotation.
Thanks for some info, that explains this result.
Tom Sweep1_Freeform.3dm (47.0 KB)
rhino 5 help:
“The Freeform option generally uses the rail-tangent cross-rail curvature direction.”
rhino 7 help:
“The cross-section curve rotates to maintain its angle to the rail throughout the sweep.”
with my little geometry-knowledge, and not being a native english speaker - either i still don 't understand both sentences,
or i would expect another result:
The cross section should stay in the same angle inside the curves Frenet-Serret-Frame.
sorry to reactivate this old topic, but i found another sweep1 issue here:
and still _sweep1 freeform does not behave in a nice and predictable way for freeform curves with a single cross-section.
so maybe someone can have a look at both aspects… thanks
