Simplest set of edge curves from edge sharing surfaces

Dear all,

I am trying to create the simplest set of edge curves from a number neighboring (edge sharing) surfaces.
Using silhouette I am able to create curves from the surfaces edges, but I am not able so simplify this set of curves so that you don’t end up with duplicate edges.

The final product should be one polyline that could act like a stencil, when the polyline is intersected with a surface, to create again the set of surfaces.

I hope this is clear what I am looking for and thank you for your time.


Hi Lukas- I am not sure I get what you want but try: Join all the surfaces, and then DupBorder… is that it?


By Join do you mean select all? Or is there a special command like merge?
If I don’t do a join before it will again create duplicated edge curves lying on top of each other.

Hi Lukas- I meant select all the surfaces that share edges and Join them- hopefully the result will be one polysurface - then DupBorder on the result… but I am not sure if that is really what you are after- can you send a simple example?



I’m interpreting your post to mean you want the final output to be multiple surfaces, as was your starting source set, not a single surface, as Pascal intended. Pascal’s method would get rid of the common borders altogether.

After you run the Silhouette command, SelDup will cull the duplicate curves so you can delete them. You won’t be able to join the edge curves into a single curve, because the shared edge creates more than one enclosed region, so you will have to group them.

However, if you are using the curves to split surfaces, Rhino doesn’t care if there are duplicated curves since it is splitting that line anyway. I would probably just select all the source surfaces, run DupBorder, and group the borders. That way you can later ungroup if you only need some of the splitting curves.

I have found a more elegant solution, which involved me rewriting most of the code and running in to some new Brep domain problem (see new post).

Since I am only interested in these edges I have altered my algorithm of generating these edges,
so as to not creating any duplicate or unwanted edges at the time of their creation.

Thank you all for your help. I consider this closed :smile: