Merge several surfaces ( from polysurface) in one signe surface

Rhino Rhino for Windows
1

Hello ,

contexte:

I need to have a clean single surface for after meshing it for conputational fluid simulation.
Here a picture to have a overview,

forum_rhino
forum_rhino.jpg763×488 118 KB

I exploded a polysurface ( double curvature) in more than 14000 single surface. ( “A” on my pic)
Using : _MergeSrf I can join them 2 by 2. ( “B” on my pic)

Using a lot of _MergeSrf adding each individual element, I can finally merge a bigger part ( “C” on my pic)

But I can not do that for all my file.
the command _MergeAllFaces do not success ( as said in the doc : co-planar polysurface only)

Is there a comand which do that ?
A way using GH ?

Many thanks
Have a nice day

Fred

2

Hi Fred - I don’t see a clean way to do that - a messy way might be this:

  • Join all the surfaces.
  • Make sure isocurves are not displayed for the results.
  • ExtractWireframe
  • Then SelChain and Join to get the individual long curves in each direction.
  • NetowrkSrf.

-Pascal

1 Like
3

other option could be using _Patch
Extract the vertices first

patch%20from%20points
patch%20from%20points1189×840 427 KB

then you can project curves to get the smooth edges for resurfacing

4

Hi Pascal ,
Thanks for your reply.

I think i understood your strategy. But my problem is SelChain ask me at each junction which curve to select , so it heavier then doing it by hand.

Please find below a more zoom out view of my problem (airfoil)

forum_overview
forum_overview1272×443 99.5 KB

and a view when I use Selchain , i’am missing smething ?

foruem_selchain
foruem_selchain719×617 160 KB

If it can help the 3dm file attached ( zipped):
airfoil_poysurface_forum.zip (13.5 MB)

Hi Diego Krause,
Thanks also for your proposal , unfortunatly _Patch is making a surface too different from the original one.

Thanks all
Have a nice day
fred

5

Hi Fred - set chain continuity to Tangent, not Position. Any better?

-pascal

6

Hi Pascal ,
no it doesn’t work at all with tangent. only position.

7

Hi Fred - set a high angle tolerance on Tangent - like 45 - that way it will ignore the 90 degree corners and just track along the ‘correct’ direction.

But I see this is a faceted thing, not smooth - you may want to use CurveThroughPolyline once you have all the segments joined.

@fred3 - see the attathed. I only did a segment…
airfoil_poysurface_forum_partly.3dm (5.5 MB)

Joined the curves (SelChain) and since some are arcs, I changed the degree to 1 and then SimplifyCrv to get polylines, then CurveThroughPolyline and NetworkSrf.

-Pascal

1 Like
8

Ok I got it , thanks a lot for the exemple file.

many thanks for your time
Have a nice day.