What command to flow curves along a surface?


#1

Hi,
V5

I have a trace I have done using curves of an emblem brought into rhino as raster image and wish to flow it and keep nudging it about on a surface until happy with location.

How is that done ?

Flow along surface says its for objects but I have closed curves.

Steve


(David Cockey) #3

A better method than my deleted post.

Create a base surface from the target surface using UnrollSrf, Smash or Squish. Position the closed curves to be flowed on this base surface.

Start “Record History”

FlowAlongSrf with Copy=Yes
Select the curves to be slowed.
Pick a corner of the base surface.
Pick the corresponding corner of the surface which the curves will be flowed onto.
The curves should be on the surface.

To move the flowed curves on the target surface move the original curves on the base surface. The flowed curves will move because History was enabled.

To change the rotation of the flowed curves Rotate the original curves relative to the base surface.

To change the proportions of the flowed curves change the proportions of the base curves.

Edit: last sentence corrected


(Pascal Golay) #4

Hi David - for this workflow, UnrollSrfUV might be a better way to get the flattened surface as the UVs will match up better than from UnrollSrf and the mapping less distorted for surfaces that have uneven uv distribution.

-Pascal


(David Cockey) #5

Assuming the surface will “unroll”.


#6

Hi, followed the steps as follows:-
Create a base surface from the target surface using UnrollSrf, Smash or Squish. Position the closed curves to be flowed on this base surface.

Used UnrollSrf, when it asks for selecting curves on the surface, er um, what curves as I have selected a surface, no curves on it, so hit enter.
Fuselage became flat and viewable in TOP view, though the rear of it was now at aircraft engine end and vice versa.
Positioned emblem on the narrower part of this unrolled surface, orientated as it would be on the fuselage.

Start "Record History"

clicked on Record History. it became highlighted, during this process that highlight is lost, is that ok ?

FlowAlongSrf with Copy=Yes
Select the curves to be slowed.

did that.

Pick a corner of the base surface.

Not sure of this, had arrow tool so clicked as near corner of the flattened fuselage at its rear area as I could, its not obvious if the corner is the top or bottom of the fuselage.

Pick the corresponding corner of the surface which the curves will be flowed onto.

in perspective view with arrow tool selected the rear fuselage underside. I see highlighted Record History become non highlighted.

The curves should be on the surface.
saw emblem but it was not orientated vertical as on flattened skin, instead stretched and flowing from rear forwards.

To move the flowed curves on the target surface move the original curves on the base surface. The flowed curves will move because History was enabled.

Move curves on base surface and it moved, still lying on its side at the moment, at least it moves, but its long and thin and distorted a bit.

To change the rotation of the flowed curves Rotate the original curves relative to the base surface.

so I need to have the emblem horizontal on the base surface to make it vertical on the fuselage.

rotate it horizontal yet still remains heading rear to front.

Move it towards top of rear fuselage skin on base skin, it doesnt move up fuselage, it moves forwards towards engine.

To change the proportions of the flowed curves either change the proportions of the base curves.

as its very stretched, to have to try and distort the base skin to get it back to its shape is not practical. Cant see how I am going to distort base skin to get emblem back to a rectangle shape and how will I know its proportional again?

Steve


(David Cockey) #7

[quote=“Steve1, post:6, topic:41929”]
Create a base surface from the target surface using UnrollSrf, Smash or Squish. Position the closed curves to be flowed on this base surface.

Used UnrollSrf, when it asks for selecting curves on the surface, er um, what curves as I have selected a surface, no curves on it, so hit enter.Fuselage became flat and viewable in TOP view, though the rear of it was now at aircraft engine end and vice versa.Positioned emblem on the narrower part of this unrolled surface, orientated as it would be on the fuselage.
[/quote]Selecting curves on the surface is optional. Set Labels=Yes in UnrollSrf for labels which will show corresponding edges.

If the unrolled surface is inverted with the exterior pointing down then either mirror it or rotate 180 about an axis in the xy plane such as one parallel to the x axis or the y axis.

[quote=“Steve1, post:6, topic:41929”]
Start “Record History”

clicked on Record History. it became highlighted, during this process that highlight is lost, is that ok ?
[/quote]Yes, History is recorded for the FlowAlongSrf command only.

[quote=“Steve1, post:6, topic:41929”]
Pick a corner of the base surface.

Not sure of this, had arrow tool so clicked as near corner of the flattened fuselage at its rear area as I could, its not obvious if the corner is the top or bottom of the fuselage.
[/quote]Labels from Labels=Yes in UnrollSrf will help identify corners. Also see comment above about inverted unrolled base surface.[quote=“Steve1, post:6, topic:41929”]
Pick the corresponding corner of the surface which the curves will be flowed onto.

in perspective view with arrow tool selected the rear fuselage underside. I see highlighted Record History become non highlighted.
[/quote]That concludes the command and recording of History.

[quote=“Steve1, post:6, topic:41929”]
To move the flowed curves on the target surface move the original curves on the base surface. The flowed curves will move because History was enabled.

[quote=“Steve1, post:6, topic:41929”]
The curves should be on the surface.saw emblem but it was not orientated vertical as on flattened skin, instead stretched and flowing from rear forwards.

To move the flowed curves on the target surface move the original curves on the base surface. The flowed curves will move because History was enabled.

Move curves on base surface and it moved, still lying on its side at the moment, at least it moves, but its long and thin and distorted a bit.

To change the rotation of the flowed curves Rotate the original curves relative to the base surface.

so I need to have the emblem horizontal on the base surface to make it vertical on the fuselage.

rotate it horizontal yet still remains heading rear to front.

Move it towards top of rear fuselage skin on base skin, it doesnt move up fuselage, it moves forwards towards engine.
[/quote]Sounds like the surface may be inverted. See comments above.

[quote=“Steve1, post:6, topic:41929”]
To change the proportions of the flowed curves either change the proportions of the base curves.

as its very stretched, to have to try and distort the base skin to get it back to its shape is not practical. Cant see how I am going to distort base skin to get emblem back to a rectangle shape and how will I know its proportional again?
[/quote]“either” in my earlier post is a typo. Ignore. Verify the unrolled base skin orientation. If the flowed curves are still distorted then alter the base curves until the flowed curves look correct.