Hello Dear All,I'm struggling since 3 years about that issue, maybe someone can help about it;As you can see down below i have kind of vortex shape (surface) and would like to extract u and v isolines as polyline or spline for that extractisoline command just giving random splines, xedges command giving only top and bottom circles, if i convert that shape into mesh it's giving distorted mesh body, i can't also snap intersection of isolines to drawing with 3dpoly, i have no idea left can someone tell me what can i do more?I just need exact position of isolines itself or intersection points.Note: I found that script many years ago but won't work either!Script:https://adndevblog.typepad.com/autocad/2014/03/extracting-isolines-from-surface.htmlThank you and Best Regards
kurubakla2019-05-13 13:56:23

The [CMD]SURFEXTRACTCURVE[/CMD] command can extract splines at any given point of the surface. [CMD]SPLINEDIT[/CMD] can then convert the spline to polyline.

Hi there @Vladimir Michl,Extractisoline=surfextractcurve I already tried that command but it's giving me random lines on surface, i need isolines precisely as shown as on model or at least their intersection points, in anyway i can't snap of this isolines this is the real problem! Nevertheless thank you very much for your respond VladimirCheers

The displayed isolines are not some type of geometry (you would snap to) - these are just visual elements. You can change the number of displayed isolines in the object's Properties palette (Ctrl+1). The easiest workaround would be to create work points on the source profiles.

Hello kurubakla and Vladimir, I think that I have faced that kind of problems with some very complex 3D mesh given for topo survey by an other company and when I asked them about the work on AutoCAD they answered that it's possible to create cuts through that mesh with an other software ( like we do with real 3D solids with the command SLICE or SECTION that is not working here on a non 3D solid ).

In other words, if you want to extract curves, do it on a real 3D solid.
philippe JOSEPH2019-05-17 13:45:08

Hello Dear All,Answer has arrived for this topic in here:https://www.cadtutor.net/forum/topic/67626-extract-loftsurface-isolines/Thank you for all your responds