Dead UV questions.

dmitriy.shpilevoy — Tue, 03 Jun 2025 08:34:49 GMT

UPD: Ugh, serves me right for being lazy and grabbing UV reading code from previous script, instead of searching docs for proper way of doing it.
Should have used $.Unwrap_UVW.getVertexPosition t v

After a series of unfolds and welds, something happens with UVs.
For example, I'm getting vertex index from face, but max gives an error when I try to get this vert's coords.

$.Unwrap_UVW.GetVertexIndexFromFace 2 3 674 polyop.getMapVert $ 1 674 -- Runtime error: Mesh map vertex index out of range: < 1 or > 448: 674 -- MAXScript callstack: -- thread data: threadID:3220 -- ------------------------------------------------------ -- [stack level: 0] -- In top-level

Questions are:

1. How to detect it
Atm seems like I can check it by comparing these:

polyop.getNumMapVerts $ 1 448 $.Unwrap_UVW.NumberVertices() 688

2. How to solve it
So far only solution I found is to collapse the stack. Ideally, I would like a way that allows me to fix it with code, something clean and simple, similar to polyop.deleteIsoVerts $ for example.

3. How to prevent it

Only operations are unfold and weld on current selection

$.unwrap_UVW.unfoldMap 1 true $.unwrap_UVW.weldSelected()

Anything wrong with that, should I do it in some different way?

Attaching a max2021 file in case you like puzzles and willing to investigate.

Re: Dead UV questions.

denisT.MaxDoctor — Tue, 12 Aug 2025 18:26:43 GMT

GetVertexIndexFromFace gives you the index corresponding to the current map state defined by the Unwrap_UVW. The Polyop method returns you data before the modifier. If you want to get the current map vertex position, use the current mesh and meshop methods.

meshop.getmapvert $.mesh

topic Dead UV questions. in 3ds Max Programming Forum

Dead UV questions.

Re: Dead UV questions.