I have encountered an issue pertaining to importing a mesh to Roblox. I exported this mesh from blender as a .obj file and imported it to Roblox and set it to a mesh part; for some reason though two faces of the mesh became deformed. If you have experienced this issue before or know how to resolve it I would love to hear, thanks.
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Could you put the model somewhere for us to take a look? Make sure that when you export it doesnt apply any weird modifiers, and make sure there aren’t any n-gons on the mesh.
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Edit: Figured out how to convert them to triangles. I am still curious though to why n-gons are bad (I am new to modeling in blender). So it is bad to have any face with more than 4 vertices?
The two faces that are getting messed are n-gons. How might I convert them into triangles; I think I remember some modifier that could?
Side note, how come the other n-gon faces are not getting rearranged then?
Roblox only really understands triangles for its meshes. The import process does a very simple translation for N-gon to triangles which may not be correct in all cases. When exporting meshes to Roblox, make sure that all polys are triangles to ensure the most accurate importing of your geometry.
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Ok, thanks for the information.
[quote=“NuclearUniverse, post:3, topic:102560, full:true”]
Edit: Figured out how to convert them to triangles. I am still curious though to why n-gons are bad (I am new to modeling in blender). So it is bad to have any face with more than 4 vertices?[/quote]
It’s not so much that n-gons are bad, just that they need to be triangulated to be rendered in Roblox’s engine, and there is always more than one way to triangulate each of them, and the results are often not identical (particularly in how UV mapping is affected). If you decimate (as needed) and triangulate in Blender with modifiers, you can pick the algorithm options that get you the visually-best result, and know what you’re going to get. When a decimation step is involved, applying it and then triangulation will give you an exact triangle count too.
Speculation only, it looks like some curved areas may have gotten triangulated into lots of very small, sliver-like triangles whose shortest sides then got iteratively collapsed (think of one sliver growing by repeatedly merging with the one next to it… each incremental change is small, but the end result can have dramatic accumulated error). You can see this sort of thing happen if you play with the decimate modifier in “collapse” mode as you start crushing down the fidelity of a mesh. If this is what happened (or similar), it may have just been a tolerance thing in this one area, or the consequence of where on the mesh the optimization started; something we think of as symmetrical really isn’t once values get rounded.
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