Noob question: Quads or Tris?

Xerilon

I have noticed that every "professional" modeler do their low poly models in quads only, and I understand why as Zbrush etc. really mess up a triangulated mesh when subdividing.

On the contrary most engines translate all models into Tris only, and I have experienced that on a symmetrical character model, the Quads are automatically split into Tris in one direction (in the engine), giving some minor yet weird deformations on one side of the body.

Also I have seen good modelers that do not care whether it's this or that mixed in their model.

I figure it would be practical for me to model a low poly first, then unwrap it, take it into a sculpting app, export with normal map, but should this be quads or tris? Should I make a triangular symmetrical duplicate and project the normal map onto it or what?

Ben Apuna

Normally if you are going to take a mesh into a sculpting app to add definition and details the you are making what's called a "base mesh". It's best to keep the base mesh as evenly spaced quads. This is not a hard and fast rule though, you can get away with a few triangles or ngons here and there on the base mesh but it's sort of on a case by case basis. After you are done sculpting your base mesh you will generally need to bring it back into max/maya/etc... and build (and create UVs for) a low poly or game mesh that you will then project the high poly details down onto via the normal map. In the end most game engines will need a triangulated mesh though some can handle quads (and maybe ngons not sure...). Sometimes it's better to triangulate the game mesh yourself (before you bake the normal map) if you encounter issues with your normal map being baked with a different triangulation than the game exporter creates for you.

To be more clear your base mesh is usually not going to end up being your low poly, it's just there to make the sculpting process easier. You then make the low poly mesh to follow the shape of your high poly using tris or quads or whatever gets the job done.

Xerilon

OK, thanks for your detailed explanation, Ben! I understand perfectly now

Mark Dygert

Whatever works to get the job done for whatever you're doing. Games work in tris but quads are easier to work with, selecting rings and loops, converting that to poly selection all fast ways to work but it doesn't work with mostly tris.

If you're using 3dsmax its easier to control hidden edges then it is in Maya. But in Maya you can force edges by creating visible edges, it often breaks loops and rings but it works. I'm sure there are other ways people have found to combat the constant recalculation of hidden edges in maya, so the info is probably out there somewhere...