# Triangle meshes

Hey =) im wanting to do modeling for video games, and i have looked at some model rips from games such as doom 3 and a few ps3 games… all the models are made from triangles… i have always been told that you’re supposed to stay away from triangles, if thats true then why are all video game models (even modern ‘next-gen’ games) made from triangles?

They’re that way because of ‘tesselation’… it’s easier for a 3d engine to draw triangles than quads. Tesselating something doesn’t change it’s geometry or edgeflow, but if the triangles are in the wrong place for the bone deformations, the model will look wrong at the joints.

Modeling and animating with quads is a lot more efficient in terms of planning and executing topology, weight painting, deformation smoothness, and a whole raft of other issues. If you use a Subsurf modifier, or Multires for sculpting, triangles create nasty little spots where surfaces don’t behave well.

Game models are undoubtedly modeled first in quads and then tesselated, and the tesselation is likely done with an eye to managing the deformation at certain key points like elbows, knees and shoulders, because a quad can tesselate in two ways, and which way it goes (how the diagonal between quad corners is oriented) can affect deformation in big ways in some areas. Easy enough to do in relatively low-poly models (like for games), but in higher-density meshes it’s just better to leave things in quads.

ah ok… i think i get it… thankyou for the info =D

A simple case – one quad (4-sided mesh element). It can divide into 2 triangles in 2 ways, depending on which corners are connected by a new edge. Now think of the quad folding along that new edge – very different shape depending on which way the edge goes. For a perfectly square quad, the two different folding options would be at right angles to one another

In a game model you want to be able to control the folding (deformation) as much as possible, so joints look right when they stretch and crease as they move.

Here’s a brief visual aide to chipmasque’s explanation. Good luck with your modelling, btw. Video-game characters can be hard to make; no sub-surfaced mesh.

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I hate it when people say that! As long as you’re not using Subsurf or Multires, you can go crazy with triangles all you want. Quads are a little easier on the eye and allow you to select loops, but that’s all.

lol…

yea i have gotten used to working with quads, so i think ill keep working with them