Blender faces - quads vs tris

[Sardaukar]

Hello blender commuinty. How are you doing, I hope you are all having a wonderful day.

I'm very new to 3D modelling softwares, Blender is the first software I ever use and i started around 2 weeks ago.

So I was watching a few blender tutorials and came across Blender Guru - Andrew Price, he was doing the anvil tutorial, and one thing he mentioned regarding faces is that you should always make faces of 4 vertices. Because anything less or more causes issues for the Subsurf Modifier.

As he was talking about this point he mentioned the use of tris if its for games. Because game enignes use tris instead of quads.

but then this got me thinking. if im going to make quad faces because blender prefers it but i need tris for the game enigne... am i not causing a problem? at least when ported to the game engine. or is it that the export method turns quad faces to tri faces?

when is it ok to use tris, pentagons, or hexagons?

[xdshot]

No much differences. The polygons might be triangulated after exporting to game engines anyway if needed.

[The Renderer]

It is trivial to turn quads into tris (just cut them once or twice) and depending on the game engine and format it is done automatically or the exporter does it. So always use quads.

Generally it is best to never use anything other than quads but if you have to or really want to use N-gons or tris, it's best to use them a) in places where they won't be seen or b) in flat areas. But, again, if you are starting out, just don't use them at all until you get a feeling for when they won't lead to issues.

[Sardaukar]

I see, thanks for the answers.

[BhaalSakh]

Tris are totally fine for hard surface models such as buildings. In fact, you'll most likely need them to fix ngons left by booleans.

[nazgulsenpai]

As a last step before "finalizing" a model I always triangulate faces (edit mode, T) to eliminate ngons. If you use the cylinder primitive in blender, by default the Caps are ngons, and I don't trust myself as a modeler enough to believe I haven't left a show of ngons. It DOESN'T affect your UV mapping either, and if you do a limited dissolve after (edit mode, X - Limited Dissolve) you can clean up 90% of the sloppiness newbie like myself can leave behind. It's a matter of preference but I'd always recommend triangulating any mesh, especially after your done modeling. Triangulation also makes Sculpting look more authentic as your entire surface isn't a square grid.

[BhaalSakh]

Originally posted by 指輪の幽鬼:

Triangulation also makes Sculpting look more authentic as your entire surface isn't a square grid.

Lulwut?! This isn't true at all, the square grid isn't visible if you smooth shade your mesh.

[nazgulsenpai]

Originally posted by FlacidSnake:

Originally posted by 指輪の幽鬼:

Triangulation also makes Sculpting look more authentic as your entire surface isn't a square grid.

Lulwut?! This isn't true at all, the square grid isn't visible if you smooth shade your mesh.

Yes you can also smooth shade your mesh.

[still__alive]

The concept that Andrew was hinting at is called topology. Maintaining good topology will allow you to have better control over your mesh, it allows for better deformations (animating), and it will prevent shading/lighting issues. Here are a few good youtube links about it.

https://www.youtube.com/watch?v=VudCtEtNXbI
https://www.youtube.com/watch?v=ggADPN06mSk
https://www.youtube.com/watch?v=zXsYgRSrNr0
https://www.youtube.com/watch?v=E3ycw3-P7sg

[nanobesspark]

every quad is a two triangles in fact.
but modeling in quads is a very good practice to keep topology well defined and clear.

[still__alive]

I'm pasting my post from another thread here:

Originally posted by still__alive:

C for circle select, as mentioned

L for linked verts, as mentioned

B for box select, left click and drag

Alt + rightclick on an edge to select that whole edge loop

Ctrl + alt + rightclick to on an edge to select the face loop perpendicular to that edge

Holding shift down with those last two will let you select multiple edge or face loops

The "A" key will deselect everything selected, or select every vertex if nothing is selected

The relevance is that good, quad topology will let you use those edge and face loops selection methods. On a triangulated mesh those are not going to work. Just an example of how good topology makes it easier to work with your mesh in various ways.

Loop cuts are kind of similar; you make those with the ctrl + r keys. You can make these wherever you can select a face loop (ctrl + alt + rightclick). You won't be able to add extra geometry via loop cuts to a triangulated mesh.

[jompers fan]

i'm pretty sure blender handles quads as two tris under the hood, since that's the easiest way of handling 3D objects in computing