This mesh causes "Index was outside the bounds of the array"

[josemendez]

Damn, I kinda feel like I already asked this question and got the same response like 8 month earlier, if you feel that too - sorry for wasting ur time. I promice I will improove

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I've checked what non-manifold means and I am very shocked really, it kinda feels like there is absolutely no way to create something like a shirt mesh without running into this problem. How does one avoids creating non-manifold meshes? Especially given your requirenment of mesh being one-sided?

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No really I am stuck: I cannot imagine how can I create anything that would be non-maniford cloth-wise. I am just stuck.

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I am pretty sure the "Flag" mesh you use in your project is non-manifold. How is that working? Seriously I am VERY confused.

Hi,

In plain english, a non-manifold mesh is one that does not represent a continuous, closed, smooth surface. Common sources of non manifoldness:

- Triangles sharing no edges, but sharing vertices. (there's a couple of these in your shirts sleeves)
- An edge shared by more than 2 triangles. Commonly seen when modelers try to create two-sided cloth by just duplicating every face in the mesh and flipping them, essentially making the entire mesh non-manifold. If you require two-sided meshes you can: use proxies, use a two-sided shader, or use two materials one for each side (this last approach is used in all Obi sample scenes).
- Edges adjacent to 0 faces. (antennae-like edges)
- Rogue vertices (vertices that are part of no edges)
- Adjacent faces with normals pointing in opposite directions (imagine a table whose "top" side abruptly becomes its "bottom" side...not possible in real life, should not happen in 3D models)
- etc.

Border edges (edges shared by only 1 face) are generally regarded as non-manifold, but these are allowed in Obi (not allowed for 3D printing though, which does require perfect non-manifoldness). The meshes included in Obi are all 2-manifold.