are Tris the devil?
polycounter lvl 10
My 3d modeling instructor is obsessed with us quadding things out, even though he's previously stated that tris were ok, but quads were preferred
(referring to triangle polygons and 4 sided polygons, in case I'm using some weird nonexistant terminology)
is his obsession founded? or are triangles ok in some places?
(referring to triangle polygons and 4 sided polygons, in case I'm using some weird nonexistant terminology)
is his obsession founded? or are triangles ok in some places?
Replies
I try and keep things largely quad-based during the modeling and unwrapping process as it makes selecting edgeloops easier, or if I plan on sculpting on the area, but other than that triangles have never hurt me.
I always triangulate before baking.
And at the end when it comes to importing your mesh into a game-engine, they will be triangulated anyway.
There are 3 reasons that quads are better than triangles.
1. Quads are easier to 'read'. Triangulating a model makes it a lot harder to figure out what the mesh flow is doing, and overall makes it look a bit more complicated. I have had riggers complain that I gave them a triangulated model, since it made it harder for them to understand the topology.
2. Some tools only work with quads. Edge loops, for instance, tend to act unpredictably around triangles.
3. Triangles create poles when subdivided. These poles cause pinching and stretching. Poles will exist whether or not you use triangles, but using triangles creates additional poles, sometimes in unexpected places.
http://www.polycount.com/forum/showthread.php?p=1247603
On the flip side, triangles have advantages over quads in some instances. Most notably, every quad is 2 triangles anyway, but the program hasn't decided which way it wants to cut the quad. Triangulating forces the program to make up it's mind. Feeding a quad mesh to xnormal, for instance, will usually give you unpredictable results since you aren't sure how xnormal decided to cut the quads. Using triangles in strategic places can improve deformation, since otherwise the program of choice might decide to cut the quad in some really strange way. Triangles are also obviously useful for controlling mesh flow and density. Instead of running an edge loop all the way around your model, you can simply end it with triangles when you don't need the extra geometry.
That's a problem I've run into a lot with teaching people about 3d modeling type stuff. It's really complex and interconnected so that seemingly simpl questions like "are tris good or bad" and "should all the uvs be in one square" have really complicated answers.
Skinning a triangulated is much more difficult because grow and shrink selection don't work well.
And if triangles were the devil, I'd of been fired a long ass time ago for bad practices.
As a student I think it's easy for a lecturer to sway you one way or the other, it's good to question these things and always keep in mind that the most used word when explaining anything from quads/tri's to poly counts, 2 sided materials, use of alpha etc etc etc... is "It depends"
Lastly though, don't be afraid to make mistakes, because some of them won't be.
My instructor has basically said that triangles on a model are considered unprofessional, but my issue is that I keep running into spots where I can't quad a poly without adding an entire edge loop, or messing with the geometry around it in ways I don't fully understand. I've only been modeling for about 2 months and the program I'm using (Maya 2013) isn't very beginner friendly.
The interactive cut tool in particular seems to hate me and my attempts to make good geometry.
It's possibly that what your instructor is trying to teach you is topology control. That is to say, you should control your model's topology - it should not control you. In the long run, there isn't anything inherently cancerous about triangles. But I would suggest that for now you should stick to quads. It's a handicap that will teach you about ways to plan out your model's edge flow, and how to add geometry in a controlled way without resorting to tris. Both are good skills to have.
They added that tool in fairly recently, and I hate it's guts. There was an older tool that did pretty much the same thing, but I liked it better. It's still in there, it's just hidden. You're looking for 'Split Polygon Tool'. You can either bind it to a hotkey, or find it in the radial menu. For the radial menu, be in object mode, select a piece of geometry, then hold shift and right click. Hover over split, then hover over split polygon tool.