Surface to surface, ugh!

Please help. No matter what I do, I seem to create these offsets between surfaces when doing landscape design. I’ve watched several help videos, but when I try to apply the techniques I get these offsets.

My work flow, typically is:

  1. use patch to create a surface from contours or points > draw 2D roads, walls and paths at zero and project curves to surface > split surface > work surface, such as extruding a curb along the surfaced edge > select or duplicate edge curves > close curves to make a boundary > patch > trim area outside of boundary
  2. draw 2D roads, walls and paths > use control points to move the road or feature to various z value points > select or duplicate edge curves > close curves to make a boundary > patch > trim area outside of boundary

I’ve attempted to use a single unsplit patch over a wide area, but moving tens or hundreds of surface points has not been very accurate for me. I could double down on the effort, but I’m hoping for a more efficient work flow.

As you can see in the attachments, my work flow creates offsets between surfaces. I’ve yet to find an efficient way to close those rips - or better yet - prevent them in the first place.

If there is a tutorial or you have suggestions for a good work flow it would be super.

i am not fully sure what your issue is, are you trying to get rid of the gaps forming after trimming the road area away from the terrain? if so what could help maybe would be to extract the points or use the rendermesh from the entire region meaning roads plus the terrain and use a big patch with a good resolution which engulfs all the terrain. the result might be a more continious terrain to start with.

best would be to place at least a little part of your file that people can experiment to their likings, building something like this up from scratch or trying to theoretically solve this issue, is probably keeping people away from helping i suspect.

Hello - the patch is not going to meet up with arbitrary surfaces at every location - the way to do this is to trim the patch back a little extra (i.e. make the trim with an extra wide road) and then create one or more bridging surfaces to the edge of the actual roadway.


Thanks. When I have a moment, I’ll extract these objects to a smaller file and post it.

Pascal, thanks too.

If the bridging surface is a patch too, I assume I’d have the same problem, to a lesser extent. Are you suggesting making the bridge surface something other than a patch?

Is there an advantage to doing this with a mesh instead of a nurbs surface?

Yes - there are tons of surfacing tools - several of these would be suitable - Loft, BlendSrf, come to mind as good candidates. If you can post a small example file it will be easier to help.