Rhino polysurface object is not valid - how to fix?


Having issues in joining some fairly simple geometry, although both closed solids, they report as invalid objects, with the rather cryptic “brep.m_L(26) loop is not vaild. end of brep.m”… etc. etc. etc. Using surface edit tools, no naked edges are found. How can I fix, nothing short of regenerating all geometry?


Try exploding the polysurface, then Untrim it and re-trim it - you can use KeepTrimObjects to keep the curves used for trimming. If you keep the trim objects, look for small/non-visible curves. I usually do this by comparing the number of curves selected by the SelCrv command and a manual selection. When SelCrv selects more curves than a manual selection, deselect all curves you can manually deselect. Then press delete to remove any small/non-visible curves.

Another thing: explode and use SelBadObject to select any bad parts of the polysurface. You can use the same approach as above, but with SelSrf/manual selection.

Hi Alan - ExtractBadSrf will get you the faces that are bad - then, very often, untrim-retrim as menno describes is a good way out. Feel free to post the object here or send to tech@mcneel.com, using www.rhino3d.com/upload if the file is large. Just send the polysurface, not the whole model if it is a complex file.



Cool, I did not know that one :smile:


Thanks for the pointers… I need to remember the ExtractBadSrf command, the only problem is trying to remember the 1,000,000 plus variables with all of this :smile: