How do I create a swept surface with one rail and an planar section curves in parallel planes which has all V isocurves exactly in planes parallel to the section curves?
Here is a simple example of curves and rails: SweepQuestion1.3dm (32.5 KB) Please note that the rail and section curves may be more complex than this simple example.
Sweep1 with the "Roadlike Top"option should create the desired surface for the example rail and curves based on the description in Rhino Help.
Roadlike Front
The shape curve maintains its angle to the Front construction plane throughout the sweep.
The shape curves in the attached example are all in planes normal to the Front construction plane. Unfortunately the shape curve using Sweep1 with the Roadlike Front option does not maintain its angle to the Front construction plane throughout the sweep. See the attached file for what it does.
SweepQuestion2.3dm (42.7 KB)
Hi David - Roadlike ⌠it does not mean the sections stay parallel to the selected plane, even though that is also a legitimate way to handle the sections - it is a little hard to describe other than âroadlkeâ but hereâs an image of some rectangles arrayed âroadlike;â (red) and âfreeformâ (cyan) on a wiggly curve- the original is on the right:
I think you can get what you want by -
-Pascal
I probably should not have mentioned the mysterious âRoadlikeâ, too much of a distraction. I wonât mention it again in this thread.
[quote=âpascal, post:3, topic:33855â]
I think you can get what you want by -
ExtrudeCrv the path level with the Top plane.
Sweep1 along the edge of the surface using the âAlign with surfaceâ style in sweep 1:
[/quote]That gives me what I want. Not at all obvious. Thanks. Much appreciated.
An option for the section/shape curve direction in Sweep1 and also in Sweep2 to use simple blending/interpolation of the section/shape based on the input section/shape curve direction only and not the shape of the rail(s) would be very useful. It is not at all obvious why in a simple sweep the shape/section curve wiggles around between the input shape/section curves.
Just to add to the discussion, since this was the first result that popped up when I searched:
It seems that in Rhino 6 you can now use ExtrudeCrvAlongCrv to get a parallel sweep.
Weird that itâs not a part of the Sweep command, and I donât know the icon for it, but there you go.
ExtrudeCrvAlongCrv is not new in Rhino 6. It has been available in previous versions of Rhino. However it only works with a single section curve, not multiple section curves.
