Ngons

[flysouth]

Does a 3d model which contains ngons work OK with T3d?

If yes, are there any downsides?

[Bloodknight]

I was under the impression that triangulation occurs in the end regardless of quads/ngons which really as far as io know are just 3d editor things hiding triangles.

The simplest thing would be to just try, and then inspect the model in the engine

[Duion]

Works without problems, why it should not work? In the end it does get triangulated anyway I think.

[flysouth]

why it should not work?

Some tutorials I was going through said that certain game engines have problems with ngons and you will sometimes get strange artifacts.

Thanks for the answers

[Duion]

Yes, that may be true, since they will get triangulated and this may produce ugly results.

[Bloodknight]

I guess the first test should be opening the collada export back in the artists package to review what the exporter has done to the ngon.

next test would be what the game engine does to the collada file.

I am not artist enough to know anything about ngons other than its trickery at best, horrible organisation at worst, there is a reason triangles are used over and above all other geometric shapes, quads at least have a logical reason for existing, i can't see any logical reasoning for ngons personally, not even topology.

somebody who actually writes pure graphics routines would have to confirm my theory that even opengl/directdraw only use triangles, even if they do order them into strips, fans, etc.

[Duion]

You can switch to wireframe mode inside the engine to see the triangles, otherwise I would have no idea how to test what the engine does with it, but I guess it triangulates them.

[flysouth]

i can't see any logical reasoning for ngons personally, not even topology.

It not that I set out to create ngons, but if you have a cube and bevel some of the edges you will see that many of the tools will create ngons.

So the question is more about should I waste hours tracking them down and fixing them or will the engine just convert them to triangles and carry on without a problem

[Duion]

It is just one click to convert them. In blender there is a hotkey for it, or a checkbox on export, so this should not really be a problem.

Personally I just ignored if I have ngons so far and it worked fine.

[flysouth]

Does it convert them to triangles?

[JeffR]

Does it convert them to triangles?

 

Yeah, it should.

Example:

http://ghc-games.com/public/ngonstest1.png

And when imported into T3D, you can see it converts to the actual tris:

http://ghc-games.com/public/ngonstest2.png

The main thing with ngons is you're pretty much at the mercy of how the triangulation occurs, so if they appear in a spot that deforms on animation, you can get really funky results that could be avoided if manually fixed, but outside of that, they really don't impact anything. It's more just a "Principle of the thing" matter at that point.