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I need some explaining about this, I've tried googling this but I haven't really understand it. What's the deal with trids and quads? What's the purpose of each shape? Is it related to game engines or what? Why is it said that some programs like Maya favor quads while other programs like sculptris and Zbrush favor trids?
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>>539419

Technically everything gets converted to tris, but it is most apparent in vidia games. This is because its easier for a computer to calculate a tri rather then a quad. If you have 3 points, you mathematically have a flat shape, no matter where those points are.

If you have a quad, you could have an unknown face. The computer does not know exactly what to do with it, so it has to calculate it as if it were 4 faces. This is not a problem in movies, etc because you have render farms, and don't have to rely on someone outdated graphics card.

Also things like openGL don't even allow quads or ngons, because thats how it was made.

That being said, it best to model in quads, then have your model converted to tris if needed. you can read about ti here. http://blog.digitaltutors.com/modeling-with-quads-or-triangles/

Also zbrush does not like tris, it likes quads, because it allows for better subdividing.
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>>539428
opengl does support quads and polygons
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Quads are preferred for working with since it allows edge loops and subdividing. Tris are what they actually are for your GPU. A quad is two tris, a poly with 5 vertices is three tris and so on.
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So I can make a model in quads, rig it and animate it and then convert it? Or does the game engine convert it on its own?
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>>539436
If that is true what does the render actually show when a folded quad is viewed at a skewing angle?

>>539444
Doesn't need to be converted. A quaded model is always triangulated. You just look at what is called an 'isoline display' in software like maya.
A view that hide certain edges for you the human editor so you can more easily read the structure of the surface.

The reason you attempt to quad things is that this generates a surface with evenly spaced triangles as all the triangles are paired with another and of similar size.
This makes for few points on the surface where more than 4 edges meet at the same vertex at what is commonly called a 'pole'.

Having poles where many edges meet creates messy geometry when the model subdivided and cause pinching artifacts in the shading of the surface.
Poles cannot be avoided completely but A well quaded model minimize them to a few 5-pole vertices.

(Also once you understand why you actually want a quaded surface you no longer need to use quaded surfaces and instead insert triangles to your geometry where they make sense.)
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>>539436
sure, it supports it if they are on the same plane, but if not, it converts it to 2 tris.

https://www.opengl.org/wiki/Primitive



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