[Inquiry] Locking edges in place (Softeditsrf) and extracting surf edges

Hi everyone:

I’m very new to Rhino, and now experimenting how fast I can make mounds on sloping surfaces (e.g. lawn), something that is very common in landscape design projects.

So far, I’ve been using 1. Patch, and 2. Softeditsrf for this kind of task.

I have some issues though for Softeditsft-
Question #1: I can’t lock the boundary edges in place, despite the fact that the fixed edges option is already set to “yes”. Please see my screenshot.

Question #2: how to extract the boundary edge from a surface (not on a mesh but on surface)?

I appreciate any suggestions.

Many Thanks!!

Maybe you can try with other surface commands instead of _Patch. The edges you see there are not of the surface itself but the trimmed boundary you made.
If you use _untrim you will see the real Patch edges.

I see… hmm, no wonder why it keeps flying away from position. What surface command can you suggest?

Hello - if you make your patch surface with History enabled, you can move the input curves and points around to modify the shape.
@CGonz_T - see the attached simple example - move the red points and curve around to modify the shape of the patch.
PatchHistory.3dm (90.7 KB)

You can also edit the base curve at the edge of the patch.

-Pascal

Will try this out, thanks a lot for the time and info.