So I was going to start modeling for UE4 and was wondering, which gives the best performance over all?
Use triangles; theyâll end up as triangles when rendered anyway.
Use quads and avoid triangles.
Engine doesnât care and will convert everything to triangles. However, things will be significantly easier for you if you decide to increase level of details in your model later. Triangles donât subdivide nicely, and various loop-based tools wonât work on triangular soup.
The only exception is if youâre going after very old school look. Iâm talking about pre-quake1 stuff here, like âalone in the dark 1â.
And that is the reason why you should use triangles. The engine does indeed perorm a triangulation on quads (and n-gons for that matter), but you have no control over how the engine decides to do that.
Every quad can be split two ways. And the triangles themselves can be constructed many ways with the same verticesâŚ
Observe: Both polytopes are identical vertex-wise (just rotated by 90 deg):
There are clearly at least two ways to triangulate here⌠Obviously one of them is not intended 
But how should the engine know what you want? 
So, to avoid surprises⌠use triangles 
PS: Im not the screenshot srtist here, its actually from Epic.
The engine is a bit outdated, but that part about static meshes still holds for UE4
https://udn.epicgames.com/Three/FBXStaticMeshPipeline.html
No, youâll be shooting yourself in the foot and limiting reuse of your model by locking yourself out of edge loop tools.
The model you showed uses pentagon. Quad has 4 vertices in it. It is also, in almost all instances, almost completely flat.
You wonât be using this kind of low-poly geometry in any project these days. We are not in the 90s anymore.
See attachment for proper quad topology example.
I personally use both. I start modelling using quads and only use tris when necessary, if you look at the picture of a creature in the link posted as an example its mainly made of quads but if you look at the shoulder there are a few tris, thatâs basically how my models start but once I am happy with the mesh I triangulate it so I donât get any issues like the pic KVogler posted shows and if there are any small issues I can fix them before exporting, doing it that way has saved me a few head aches:).
I reuploaded the picture to better demonstrate the topology on the face, so the shoulder is no longer visible.
However, there are zero traingles in the model. No tris on the shoulder or anywhere else.
No, quad verts or more may or may not be on the same plane, and more often than not a quadâs verts are not on a plane. A triangle however is always planar.
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[FONT=Verdana, Arial, Tahoma, Calibri, Geneva, sans-serif]Actually there are as many triangles in the scene as the mesh can be split into. Just because itâs not rendering the edge splitting the quad, doesnât mean it isnât rendering as triangles.
Yes there is.
having the odd tri here and there is almost unavoidable on certain types of meshes.
Thatâs not my model, and I have no control of what they did with their content. Also, it is avoidable.
Which is why I said âalmostâ.
No offense, but this is getting ridiculous. Google âedge flowâ.
The reason why it is a good idea to use quads in modeling program, because it will allow you to use more powerful tools and subdivide model easily during modeling phase. Not because of âperformanceâ. Triangles will cause a mess when subdivision is involved and edge loop tools wonât properly work on them. âEdge loop toolsâ means that you can click one edge on the arm, it will select the whole circle that goes around the arm, and youâll be able to scale/move/rotate it, dissolve it (remove edges, while preserving geometry), and slide it up and down across surface of nearest polygons. That is not gonna work with triangles.
While GPU does render everything using triangles, that is not relevant to the issue.
Frankly, just model a high-poly human surface (human head, armor, etc), and youâll see it yourself.
I never said it was your content.
well have to agree to disagree on that.
Just to clarify: Im talking about the exported geometry.
Of course, during the design process I use quads and n-gons as well.
But before exporting them, I triangulate the model in the 3D application.
If itâs avoidable, make me a geodesic sphere mesh using quads*.
Edge loop tools should probably be using triangle strips.
*Itâs mathematically impossible - all angles on a quad average to 90 degrees - if four of them meet at every corner, you wont have the required 720 degree deficit to make a closed sphere; You need eight three-way vertices to get it to close.
Which not only applies to spheres, but also all topological derivatives of a sphere with any face anle less than 90 deg. Capsules, chamfered boxes, cones, etcâŚ
(-_-)
âŚSeriously?
Hexagon perfectly converts to quads by adding one vertex in the middle. So you can make geodesic sphere with quads. See attachment.
Now, give me a reason to have SPECIFICALLY geodesic sphere in the game engine instead of modeling objects created by your art team. You donât deal with mathematical primitives in games. You deal with objects from the real world.
Not gonna work. You have directional ambiguity. 3 sides. If you select one of them, thereâs no way to know where the loop should go.
Hereâs why you use quads:
https://www.dropbox.com/s/k66aoyl0ub2cacn/quads.avi?dl=0
By the way, the movement in the video is not âx axis restrictedâ it is restricted to the surface of underlying polygon.
I also added quad based sphere example in the attachment.
P.S. Seriously, guys, what the hell. This is getting to the level of âanti-bspâ thread. I expect you to have basic understanding of modeling, 2d art creation (both traditional and digital), computer programming and 3d mathematics. Instead I see synthetic examples made up to shoot down good modeling practice that is recommended by pretty much every modeler in the world. Donât make me disappointed.
is right; I believe itâs mathematically unavoidable . But, it IS possible to model by working with only quads and use tris for the unavoidable minority. MakeHuman have a char template with FULL quad , not a single tri http://www.makehuman.org/index.php ]
I donât believe there is anything âtechnicallyâ wrong with tris , just not very good with the human aspect of modification.
A whole load of relatively newer tools such as SwiftLoop , and graphite tools in max donât detect tris as well as quads. Iâm not sure if they even detect explicit tris at all.
My 2cents , avoid N-gons whenever humanly possible. Quads and tris are fine as long as your quads are co-planars ( 2 of the edges parallel ) . This is very important as not all quads are created equal . You will ruin your extrude and smoothing if you donât have proper co-planar. There are scripts to let you revert to all co-planar. Quads and NGons are merely âgroupedâ tris. They help to keep things manageable.
Letâs not be technical elitist and swear by one type where both have so much use.
This is where Iâm going to disagree with in regards to âUse triangles; theyâll end up as triangles when rendered anyway.â This is like saying to everybody to code in assembly language/machine because itâs all going to be understood that way by CPU anyway. The same reason why you paint in layers in photoshop though engine donât take layers.
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One would expect people giving advice to others to be at least somewhat educated in the manner of which they speak.
Using triangles is ridiculous. Go ahead and give a triangle character to a rigger and / or an animator and see how quickly youâll get laughed at (rightfully). You canât properly bend an elbow unless you have proper edge loops, and only an idiot would try to make edge loops with triangles.
That being said, being a zealot about it doesnât quite work in a production environment either. The odd triangle wonât make the whole model unusable and in many cases itâs just faster than to retopologize a good deal of the surrounding geometry to wire everything up for proper quad topology. Having a few triangles in places where e.g. the arms meet the armpits or such wonât have any detrimental effect on your mesh when it comes to rigging and animating it.
However, it goes even deeper than that. Itâs equally stupid to not use all the tools at your disposal, and triangles are a tool just like any other. At the end of the day if youâre making a very generic static mesh that will never animate, the toplogy really doesnât matter. Weâve used ZBrushâs ZRemesher for rocks, statues and such things that we know will just sit there in the scene. The ZRemesher is horrible, creating edge spirals and whatnot, but it gets the job done quickly, which is often times much more important than something which is in the end just for the artistâs peace of mind.
Last but not least, when youâre creating LODs, every single mesh reduce thatâs worth its salt will spit out results in triangles, safe for edge loops that you as important (i.e. elbows, places where your mesh bends, you donât want to triangulate those areas or your animations will go to hell).
tl;dr - Quads. Donât be stupid, and more importantly, donât give people misleading advice.
I agree with everything DamirH said.
Also, Iâd like to add that while programming tasks usually requires precision and creates desire to have âperfectionâ, that does not really apply for 2d/3d art, where one way to work is to make a mess and then clean it up (desire to get everything right on the first try pretty much belongs to the trash bin when trying to do any kind of art tasks). When people bring mathematical primitives into argument, it pretty much only means they havenât modeled much, because thereâs no need for perfect anything - no need for perfectly uniform spheres made out of quads, perfectly flat quads, etc.
âUse quadsâ is fairly solid advice similar to C++ advices given to beginners: âdonât use macrosâ, âavoid raw pointersâ, ânever use gotoâ, âfollow rule of the threeâ, âuse standard containers when possibleâ, etc.
It is solid advice that will make life easier, but there are edge cases where it does not apply.
The point of quads is that they allow mess management (quickly add/remove detail), also they work better with tesselator, and as DamirH said, joint deformations work better with them.
It would be more accurate to say that a quad is almost always non-planar. not a quad is almost always planar.
I know what edge flow is, it has nothing to do with quads, tris, or ngons. Itâs to do with flow of the edges of polys. It doesnât matter what youâre using, edge flow is an essential part of modeling. Really edge flow has nothing to do with my comment talking about how itâs actually still triangles. I was just making sure people understood that even if youâre using quads when making models the pc is still rendering it in tris. Which I thought your reply âThere are zero traingles in the model. No tris on the shoulder or anywhere else.â was insinuating that it was tri-less even in rendering.
I wasnât saying to use triangles when modeling, I was just clearing up vague information. Making sure people understood what i said above.
I believe this is nitpicking and this degree of precision is useless for people who are interested in modeling.
Letâs just say that
- I did not have the impression that youâre trying to clear the information,
- found your attempts to clear things up mislieading,
- they werenât really necessary because it was explicitly stated in the 3rd post of this thread that engine converts everything to triangles.
And leave it at that.
All the necessary info was provided in the link in the 3rd post and for some reason it went downhill from that point, into the land of silliness. Which is disappointing and reminds me of that rather unpleasant anti-bsp thread I saw before.
The useful info is available in link to the blog in 3rd post and DamirHâs answer.
Thereâs nothing to discuss beyond that.