Using the latest Sept beta, the mesher is still leaving holes in the mesh. This is frustrating, it is holding up work for a client. Is there any workaround? I try futzing with the settings, and the holes never seem to completely close.

Okay, it appears while UNIONING various bits of my model, some of it got corrupted ( ie parts of various patches went missing ), and these corrupted areas became holes when trying to export a mesh.

Hi Crusoe - I'll need to see an example of the problem in order to fix it.

If you don't want to post it here you can send it to me at moi@moi3d.com and I will keep the data private.

Also, make sure that you join any surfaces that were created individually - there is extra work that is done on joined edges to ensure a common edge structure, it is easy to get holes in the result mesh if you have surfaces that are positioned adjacent to one another but not actually joined to share a common edge.

If you send me the model data that you are having a problem with, I can look to see if it is that problem or if it is a bug that you are running into.

- Michael

If you have it in the pre-unioned state and can send it to me, I can see if I can fix up the problem with the Union or what is happening there.

There was a problem in previous releases where if you used Union in a way similar to Join, that is to glue surfaces that share a common edge rather than intersecting with one another, that there could be some unjoined edges in the final result. But that should have been fixed up with the last beta release.

- Michael

Hi Crusoe - also one other note - I just noticed that you wrote: "Using the latest Sept beta" - actually that is not the latest beta, there is a new Nov-21 release, which has the fix for the "Union as Join" problem.

- Michael

Well, it's a Heisenbug, I redid the union one-bit at a time, and that seemed to produce a volume that meshed properly. I'll try and engineer an example sometime. I'll check out the latest beta too.

Most commonly the missing mesh elements are skinny triangles/rectangles, even when the volume is perfect.

Hi Crusoe, previously there could sometimes be a problem when unioning a big batch of things where a bunch of separate small pieces were being unioned on to one larger piece.

If the internal ordering happened that many of the small pieces (which do not intersect one another) were unioned together first into a bunch of little separate volumes, before they were intersected with larger piece that actually intersects them all, that could be buggy. When you do them one-by-one it avoids this problem since only an intersecting pair is processed.

One of the changes for the Nov-21 v2 beta was an improvement of the internal sorting for how a larger batch of small objects being unioned is handled, I think it should pretty well solve this problem area.

Also in the Nov-21 v2 beta was a bug fix for meshing where there could be some skinny cracks when 2 adjacent surfaces had UV quad gridding that was very close to being aligned with one another but not quite. It fixes the bug that was reported here by PaQ:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2091.1

I can't be sure if that fixes the bugs you ran into, because I don't have any examples of that from you but it sounds pretty similar.

If you run into it again, please send me the file if possible so I can reproduce the problem over here and work on fixing it. Otherwise it is very difficult for me to work on a fix if I don't have a repro case for the problem.

- Michael