3ds Max attaching and detaching loses all materials

DarkEdgeDesign

I must be doing something obviously wrong, cant believe it's this hard.
I have Object 1 (many elements) with Material 1 applied to it, then I have Object 2 (many elements) with Material 2 applied to it...all good.
It falls apart when I detach some element off of Object 1 and attach it to Object 2. I'll export that as an obj, then re-import it and the materials are all buggered.
Please help me understand.

Eric Chadwick

Sounds like the fault of the OBJ export/import. Does it look correct in Max before export?
Also some pics would help tremendously, before and after. "Buggered" is not a very helpful description.

dimwalker

Use one multi sub object material for both objects.

poopipe

assuming OP selects the correct option when attaching the models it should all work - obj supports multiple materials on a single mesh.

Im not quite sure from memory what happens to material IDs if you detach an element that has only a single ID from a larger object that has several - it wouldn't be surprising if it modified the material ID map.

dimwalker

poopipe said:

assuming OP selects the correct option when attaching the models it should all work - obj supports multiple materials on a single mesh.

Im not quite sure from memory what happens to material IDs if you detach an element that has only a single ID from a larger object that has several - it wouldn't be surprising if it modified the material ID map.

When attaching meshes with different mats (and same IDs in my test scene) max provides 3 options.
First 2 create new multisub mat that looks as expected, but changes ID on attached part.
Third doesn't change anything and all parts have mat of the "main" mesh.

DarkEdgeDesign

DarkEdgeDesign

Okay sorry for being a bit cagey about describing this. I've been able to narrow it down to simple export from Max, i'm using this inside of daz so i use a variety of programs but dont let that throw you off. 1 shows materials inside of max all multi-surface. 2 shows the materials inside of uv mapper. 3 shows my export setting inside of max (note i did absolutely nothing to the obj inside of max). 4 shows the materials inside of uv mapper after max export. No its not uv mapper i get the same info if i re-import into max.
So i really don't understand whats happening at all. Using max 2022

DarkEdgeDesign

Hmmmm...i'm getting closer. I opened the multi-sub object and changed all physical materials to standard legacy, re-applied materials, reset x-form, re-applied materials and straight export...now all materials show up and all groups.

Eric Chadwick

Well, the yellow value has to come from somewhere. Curious where the yellow values were in the original materials.

DarkEdgeDesign

...and now I detached and element, applied an edit poly did some work, collapsed, applied material, reset xform and re-attached...and all is good. I have no idea what the hell has just happened but I certainly don't want to have to jump through all these hoops every time. If anyone has any suggestions I would like to hear them.

DarkEdgeDesign

no color values were assigned...it was all pre-substance...those color values would arbitrarily change during my testing, sometimes, green, yellow or blue.