Make a non-manifold .obj solid

[aloarjr810]

I noticed if you import in some .obj models and you tried using the "Split" tool on that imported .obj you get a (split kernel error: not manifold) error message. I then had to put it in meshmixer and made it solid, Then Layerling would be able to split it.

if possible add a make solid function (unless its already there and I don't know where its at)

[henmedia]

@aloarjr810 Thanks for the idea. You're right, there is no "make solid" function in layerling yet. Split needs a closed, watertight mesh, and many .obj files have small holes or loose edges, so it stops there. The error message isn't very helpful either.

Could you attach one of the .obj files where this happens (zipped if needed)? Then I have a real case to test a repair function with.

[aloarjr810]

non_manifold_test_obj.zip

Here is a .obj file (1.28MB) that does it and a screencap of the error message I see.

The work around I did was put the .obj in Meshmixer then EDIT>MAKE SOLID then I exported it as a .stl file.
Then I imported the .stl into Layerling and split worked on it.

[henmedia]

@aloarjr810 thank you for the file, it showed the cause right away. The body itself is closed, but the four eyes are open cups, and the body has two tiny gaps. One open spot anywhere is enough for the kernel to refuse the whole mesh, and the message only said "Not manifold".

In the next release layerling closes such openings itself. When Split, Group or Cut meets an open mesh, it caps the openings with a flat lid and tries again, and the message says how many it closed. With your file the split now works and says "layerling closed 6 small holes in the mesh first". It closes small openings and flat ones of any size. A large opening with a bent rim stays open, because a guessed lid would change the part. In that case the message now says that plainly and suggests closing it in the program the model comes from, or with a mesh repair tool.

layerling is free. If it is useful to you, a small donation helps me keep working on it.

[henmedia]

@aloarjr810 it's in 1.107.0: when a mesh has small openings like the eyes in your file, layerling closes them before a split, group or cut and tells you how many it closed.

[aloarjr810]

thank you that works well.
FYI: The program that created that model is called "MakeHuman" its a free, open source, collaborative project for creating realistic 3D Human models that can be quite detailed. It can export models in several formats- .stl, .obj, Collada(Dae), Ogre3D, Filmbox (fbx) and each has several options