Making a surface blend into another surface

I have two surfaces that share an edge. Each was created with a network of curves. While the curves are continuous, the resulting surfaces are only continuous with one another near the curves.

The BlendSrf command can help. By trimming each of the surfaces and then creating a blended surface, the problem seems solved. However, the sides of the new blended surface do not follow the original boundary. Perhaps I could get the isocurves from the blend surface, combine these with the original boundary, and create a new networked surface… but this is starting to seem kind of round about.

Additionally, BlendSrf, unless I’m mistaken, isn’t in Rhinocommon yet. So I’ve been thinking of creating my own command to take two surfaces that share an edge, and make them continuous with one another. Unless of course anybody has any other suggestions for me.

Thanks,
Sam

Hi Sam- MatchSrf is the obvious thing to try here, have you given that a shot?

-Pascal

Hi Pascal,

MatchSrf only seems to modify the two rows of control points closest to the edge. I would like the blend to go further into the surface, say a percentage of the surface perpendicular to the edge. Is there a way to do that?

Thanks,
Sam

Right, that is the difficulty with NetworkSrfs - they are typically pretty dense so the second row is very near the edge. There is no way I know of to force that further into a dense surface. I can imagine, maybe, some hacky workarounds, I’ll see if I can do anything helpful- can you post or send me the surfaces?

-Pascal

How about removeknot on a couple near the edges of interest?
clk

Attached are example surfaces.

I was thinking I could take the isocurves for the first surface, trim them and blend them into the second surface, and then use network surface again…

ChrisK, I tried removing some knots and then matchsrf, good idea but didn’t do quite what I wanted, for example the boundary seemed to move and still a sudden change, just further up the surface.

Thanks,
Sam

ExampleSrf.3dm (1.3 MB)

Hi Sam - here is a quick test - is that on the right track (Zebra-ize…)

Edit: that was a waste of time - basically, if you are willing to have the changes go deeper into the surface, just build a lighter surface… That shape does not need all the points that NetworkSrf gives it. Rebuild, move some points to get it back close to the original and then you’ll be fine for a matchSrf. \

-Pascal

Rebuilding does help. It does mean I have to rejoin the the edges to bring them back into tolerance (side question: instead of joining two edges together, is there a way to move them both to a curve?).

I still think it would be useful to have some sort of blending function that goes a distance into the surface that the user can set. But then maybe I need to spend more time designing better surfaces in the first place…

thanks,
Sam

Hi Sam- matchSrf will take a curve as the target object - for Position only, obviously…

-Pascal

Got it, no clue why it wasn’t working before…

As always, thank you for the fantastic support!
Cheers,
Sam