# Project Srf to Curve

The command I miss the most is the ability to “project” a surface down to a curve, while smoothing the Srf but keeping the edges.

But perhaps there is something like that already?

USEFUL WHEN CP-EDITING
In many cases I start forming complex surfaces (for example “hopeless fillets in corners” with a plane surface attached to corners. Then I gradually increase the complexity of the Srf’s structure, Match the edges, decrease the Control Points back again to smooth out the overly complex Srf (resulting of the Match) and then CP edit the Srf again, and repeating this pattern until it’s close to perfect shape.

But if the surface needs to follow a defining curve somewhere (which I initially use only for eyeballing the Srf), then as a last step (apart from doing Match with the edges of course) I would like to “project” the surface down to any such constraining curve (one curve at the time would be good enough for a start).

And yes, I know of course that there are many (other) ways to produce complex surfaces, but I have found that when the surface lacks obvious symmetry in the edges, CP editing can be a short cut (except for when some part of the surface must also follow a constrained curvature somewhere, and that’s where the “Project Srf to Curve” would come so handy in).

Or, is it only me day-dreaming…

// Rolf

Project a curve onto a surface is a command in Rhino but it does not sound like what you are describing. You might want try using a different word than “project” to describe what you want.

Perhaps Patch with a starting surface and Preserve edges is close to what you want.

The word “project” describes exactly what I want, it only swaps projecting Curve to Surface to project a Surface to Curve instead. Exactly that. Point is, exactly that part of the surface that lays above a curve needs to match, the rest just to be evened out towards the edges.

Patch comes with other problems, like trimming and such. No trimmed edges is part of the point using my approach.

// Rolf

Hi Rolf - try it! Patch to the curves with your surface as a starting surface…

-Pascal

Hm. That sound like an idea.

(I never though of the idea to use the CP-edited surface as a starting surface. Duh.)

Edit:
After trying around a bit I only end up with the edges let lose meaning I have to do the Matching all over again, which in turn distorts the surface. I would have to try Patching/Matching several times in order to see if I get closer each time or if I just bounce back and fourth…

But already that tells me there should be a Project- or Drape-command that pulls down the surface to the curve, while smoothing the Srf out and keeping the edges intact. That would be Gold.

// Rolf

Hi Rolf - can you post your surfaces and curves and whatnot, or send me a private message? I’m probably not picturing what you’re trying to do very accurately.

-Pascal

Hi Rolf, VSR has a match surface command where an edge of a surface can be matched to an input curve. Is that what kind of tool your talking about?—Mark