When flowing an object onto a curvong plane much larger than the base surface, rhino modifies the thickness. Can I preserve the thickness?
It is suggested that you use the FlowAlongSrf before creating thickness, and then use OffsetSrf to create the thickness.
Thanks Jessesn, I have been considering that. Unfortunately it seems to point to an overwelming number of operations in this case. The object I am flowing has many tapered serrated edges, and I am flowing many iterations of this same object onto surfaces of different size and (compund) curvature. For each iteration I would need to flow two coplanar planes (front and back of the sheet) offset each one (the inside one as a solid as the object doesn’t taper to a knife edge), delete the outside face of the inner solid offset srf, and blendsrf each pair of edges to create each of several compound curving facets. I would essentially have to build each iteration.
I see the option to preserve the normal direction; how I would like to be able to have the option to preserve the normal distance.
Sorry, FlowAlongSrf does not has this option now. the ConstrainNormal option, Specifies how the normal direction of the base surface is mapped onto the target surface.
Yes, Pick two points to define the constraint direction.
No, Use the target surface normal
.
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Yes that preserves a direction of the normal, but I need to preserve the distance of the normal.
I’m not sure this will work for you, but you might be able to use two surfaces: one for the top and one for the bottom. You would need a base surface and a target surface for both the top and bottom surface. After flowing the two surfaces, you can use duplicate border and then use either loft or sweep-two-rails to construct the edge.
Yes thanks WD, that’s what I was attempting to describe previously. It’s a bit overwhelming to face this for each iteration but I’m going to try.
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Here’s two slightly different ways of doing something like what I was trying to describe. It could be modified several ways. Here exactly the same shape is used for both the top and bottom so I only need one base surface, but two target surfaces.
This is the first method.
This is the second method. This will probably have more distortion, but you don’t have to build the edges.
I am not understanding something here. Can you post an example file where you feel it is flowing incorrectly?
FlowAlongSrf maps a base UV to a target UV. The object is deformed in the U and V as it maps from the physical space of one surface to another, but those surfaces don’t have a thickness. The Normal is a unit vector.
So while the physical size of the U and V change, the only change to N is the direction.
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Well, so much for that perceived issue, thanks Eric. The results of my flows were difficult to view other than very obliquely which gave the impression that the normal distance was stretched. ON cutting a careful section through these flowed objects I see that their thickness is indeed consistent. Many thanks.
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