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Should the ngons on the top of the cylinder be avoided or not?

Question

Eneary
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    They're usually fine, if isolated with an inset like that. I don't know how yours got twisted, though... – Robin Betts Jul 29 '22 at 19:51
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    As long as you know that it'll be triangulated when rendered or brought into an engine and can deal with the results, you can model whatever you want. :p – Allen Simpson Jul 29 '22 at 20:01
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    An easy way to guarantee a 'look' is to run the command 'poke faces' with the ngon selected. – Allen Simpson Jul 29 '22 at 20:02
  • @AllenSimpson wouldn't that create a star looking artifact? – Eneary Jul 29 '22 at 20:10
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    At worst, yes, but the way it looks here it should be flat – Allen Simpson Jul 29 '22 at 20:22
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    As long as the ngon is planar, and planar with all of its neighbors, and convex, it doesn't matter how it gets triangulated (including via poke faces) for purposes of smooth shading or for purposes of C-C subdivision, which are the two things people generally care about when they're dealing with topo. For vertex color or distorted UV, the ngon may not be desirable, and the poked face will probably be what most people want. – Nathan Jul 29 '22 at 20:25
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    Thanks for the explanation, but I have one more question that haunts me for a week. I created another model and it's center has a UV sphere's top look, which causes the artifact, do you know how to fix this? I simply can't rid of it, it connects everything in the model and it shouldn't be flat – Eneary Jul 29 '22 at 20:32
  • Hi Eneary :). Please post your last comment as a new question. You'll have better chance to get an answer ;) – jachym michal Jul 30 '22 at 09:32

1 Answers1

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Form follows function

It is all depends on what we need the geometry for.

If we are going to work with procedural geometry, and we will use such modifiers as bevel or boolean it's better to have ngons, because the faces of the model, which will be affected by the modifiers in this way will have simple topology, and therefore they will be easier to interact with the modifiers.

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It is different if we are going to use Subdivision Surface modifier. In this case there is a special workflow in which mesh consists only of quads (faces with 4 vertices), to have nice shading and avoid artifacts.

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Another option if we work with game ready models. When we are modeling lowpoly(or doing retopology) we can work with both types: ngons and quads. Ngons help to reduce the number of vertices, working with quads make UV unwrapping easier. But before baking textures and exporting to game engines we must triangulate all model to avoid baking and shading artifacts in future.

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This is due to the fact that all faces consist of triangles, but each engine interprets triangulation differently, so that we do not leave triangulation to the engine we have to make it ourselves, so that it has only one single triangulation throughout the pipeline - the one we made.

Yuri Titko
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