FlowAlongSrf doesn’t care about trimmed edges. Untrim your source and target surfaces and you’ll see what it’s doing.
Thanks Jim. I’d tried shrink trimmed surfaces and it didn’t make any difference. So I just tried untrim sad you suggest, but it didn’t make any difference either.
I’m having some success cage editing the shingle group after a flowalongsrf, but the result is a bit clunky.
A number of objects in this project, including these shingle objects, originated in Vectorworks and some of them don’t behave as expected in some cases (they won’t add to a block unless I explode them first, for example). This may be the source of the issue; I haven’t had this issue within Rhino before.
I meant, if you Untrim your surfaces, you’ll see why it’s not “filling it in,” it doesn’t care about your trimmed edges, your geometry gets mapped from untrimmed input to untrimmed output.
If that were the case – and if I’m following you – and I untrimmed the source and target surfaces, wouldn’t they change and the result of the flowalongsrf would be different? But when I do that nothing changes and the flowalongsrf result is the same… Maybe I’m missing something here.
what he probably, most likely meant but was unable to explain (
) is that you should use untrimmed surfaces. just rebuild this with edge surface for instance.
That’s what I’m saying, it doesn’t change because it doesn’t care about the trimmed edges.
Thankyou. If the base and target surfaces are trimmed (I don’t know if they are or not…) they would change when I perform an untrim or shrink trimmed surface on them, wouldn’t they?
ShrinkTrimmedSrf does not usually make an untrimmed surface, maybe in special cases where it really finds the edges. also ShrinkTrimmedSrfToEdge has the same fait.
you really have to build the base and the target surface from 4 edges without having it trimmed. Loft, EdgeSrf for instance.
what @JimCarruthers also meant but not explain properly probably, is that you can use trimmed surfaces, but flow always takes the untrimmed boundary as base and target which makes it difficult to target the outcome in some cases.
No.
Trim curves are additional information that is added on top of the original untrimmed surface, they don’t change it. And FlowAlongSrf does not pay any attention to them. So you need your start and target surfaces to be more “alike” in their untrimmed structure.
I think you can achieve it with RefitTrim + ShrinkTrimmedSrfToEdge, fyi,
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i wonder why flowalongsrf is so much slower on mac, or did you speed the clip up?
Yes, FlowAlongSrf takes over 30 seconds, where it needs to process 23 polysurfaces and 322 surfaces.
Thanks Jessen. I see how that works on the example I first uploaded. (I had to figure out that it’s Pointson and not SOlidPtsOn that shows the untrimmed configuration.)
I’m working on another part of the project now, and I get “ReFitTrim failed” when I attempt it on each of the target and base surfaces on the attached.
Yes, it’s PointsOn
Provide a new solution for you current case, how to create the untrimmed surface based on the trimmed surface. I hope it helps you.
Thanks again Jessesn. To keep going I had to do it with a weird flowalongsrf corrected by cage editing the source object but I see there are some things for me to learn about what separates surfaces from surfaces from surfaces. Too easy to assume what’s visible is all there is. Some learning ahead.
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It is important to remember that RefitTrim will usually change the shape of the surface. (There are special cases such as planar surfaces with straight trimmed edges where the result of RefitTrim will be the same shape as the input.)
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