From: AlanB (ABRADERS)
I have tried two different methods to flow the simple clip in the attachment. How do I create a flow without the distortion circled?
Thanks.
Attachments:
Flow anomaly.3dm
From: Frenchy Pilou (PILOU)
Take just a Straight Line as Start and and Arc Circle as Target! ;)
Or a filled rectangle as Start and a filled curvated rectangle as Target! ;)
From: bemfarmer
I tried planar base rectangle, and planar curved rectangle as target, but am not getting any curvature from flow.
(selection area important?)
No more time to play now...
- Brian
From: Frenchy Pilou (PILOU)
With a line and curvated curve ;)
Seems do not working with a start rectangular surface & a curvated rectangular surface as target! ???
Makes nothing!
From: Phiro
Hi,
I think the problem is from the construction of your surfaces (source and target)
If I do planar with your surfaces, I have something strange.
I redo the surfaces with a sweep process and the problem is fixed.
My result and the surfaces made with sweep function.
Your construction and the surfaces made with them.
From: Michael Gibson
Hi Alan,
re:
> I have tried two different methods to flow the simple clip in the attachment.
> How do I create a flow without the distortion circled?
I'm a little confused because you seem to have the answer to your question right in your file - use the 2nd method you have there that does not have the distortion.
The anomaly on the left one is because curve to curve flow works by treating the curves as a kind of "backbone". The rectangle curve you have as the base curve for the anomalous one is not positioned as a backbone like a centerline on the object, it's a path going around the exterior of the object.
To do a flow with that type of setup you would need to build surfaces for the base and target for the flow, not a closed curve. See attached model.
- Michael
Attachments:
Flow anomaly2.3dm
From: Michael Gibson
Hi Brian,
re:
> I tried planar base rectangle, and planar curved rectangle as target, but
> am not getting any curvature from flow.
Flow works with the "underlying surface" structure.
If you turn on control points for the surface you made from the planar base rectangle (select it and use Edit > Show pts), you'll see that it's a trimmed surface with the underlying surface being a large rectangle.
If you turn on control points for the other surface that you made from the "curved rectangle" you should see that it is also a a trimmed surface with the underlying surface being a large non curved rectangle. With the underlying surfaces both being the same you will not see any curvature imposed on the flow result.
So for the particular use of Flow you can't construct the curved one using the Construct > Planar command since that makes trimmed surfaces with the base surface being a large rectangle.
You would need to use something like Loft between the 2 curved pieces, or sweep or network - something that will generate an underlying surface that is curved instead of only a trim boundary that is curved.
- Michael
From: Michael Gibson
@Pilou,
re:
> Seems do not working with a start rectangular surface & a curvated rectangular surface as target! ???
> Makes nothing!
See my above reply - if you turn on control points for your 2 surfaces using Edit > Show pts you should be able to see that your curved rectangle is a trimmed surface with the same underlying surface as the start rectangle.
Since surface to surface flow works by using the underlying surfaces that will produce no change since it's mapping from one straight rectangle to another straight rectangle.
You need to use some other construction method for making the curved surface, not Construct > Planar. You could do a loft between the 2 curved pieces, sweep using the curved pieces as rails, or Network.
- Michael
From: Frenchy Pilou (PILOU)
yep that is more clear!
From: AlanB (ABRADERS)
Hi Michael,
Thanks for clearing up my addled brain freeze!
Much appreciated.
Alan
From: bemfarmer
Thank you Michael.
Will study some more tonight.
It is a good learning experience for myself... There are still things that I do not know :-)
- Brian
From: Frenchy Pilou (PILOU)
Why there is no "Stretch" when we use Surfaces with Flow ?
From: Michael Gibson
Hi Pilou,
re:
> Why there is no "Stretch" when we use Surfaces with Flow ?
Curve flow and surface flow work a little differently - curve to curve flow works by distance traveled along the curve while surface to surface flow works in the UV parameter space of the surfaces.
- Michael
From: Frenchy Pilou (PILOU)
Thx for precision!
