# Why Triangulate model for in game end result?

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Hi my question is why must the model be triangulated why not use it just the way it is done without having all the triangulation would that not save performance speed?

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polycounter lvl 10
The reason the engine trianglulates a model is because it is much, MUCH easier to calculate a triangle than a quad. Using the Pythagora's algorithm, triangles are win.

Some people prefer to triangulate their models before exporting it to an engine, that way you know exactly how the model will be triangulated, and you can triangulate faces exactly how you want. Whereas if you simply export, the model may not get triangulated the way you'd expected it to.

Now, I'm sure someone like Vig of EQ will come and write up a wall of text explaining in-depth why models are triangulated, but simply put, my explanation should cut it. Of course, I THINK I'm right about it, I may be way way wrong.
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mod
Working in quads is just an illusion, you're still working with triangles. The quad workflow just offers you a few ways to keep things clean, fast and efficient while working. Like Prophecies said in max and maya there are ways to define edge flow for specific areas while still working in mostly quads. Max lets you flip hidden triangle edges so you're still working in quads but the tris strip the way you want, which is nice. I think someone was working on a script that did it in Maya or they included a way to do it in 2011, but I've gone back to using max.

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greentooth
I quite interested to know about this topic for some times but haven't post it in here for some unknown reason, thanks Rock Bottom for bringing this up and for Prophecies and Vig for the answers.
Quick question; how would you normally do this triangulation in Max? I tried the Tessellate modifier in Max but it's just looks ugly, among the triangle faces, it still creating quads using this modifier. Thanks in advance for any answer guys!

_Revel
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from what i understand, 3d modelling packages tend to use more complex ways to represent 3d data (maya uses half-edge meshes). this is different to how most game engines(and gpus?) store it, which is usually just a vertex list and a triangle list. Just storing these lists instead of having edge, polygon and surface lists take up less memory.

this is mostly speculation on my part though.
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polycounter lvl 11
@Revel, select 2 vertices and use "connect" (and bind the connect function to a key, time saver :q ). You can also use the cut tool at your own risk (it's not always precise)
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mod
Revel wrote: »
Quick question; how would you normally do this triangulation in Max?
Normally you don't have to worry about it, it is triangulated when the model is exported/imported into the game. Normally I check the flow of the hidden edges with edit poly by turning on "Edit Tri." or "Turn". Both of those let you see and edit the way the edges are flowing.

As far as I know, Maya re-triangulates hidden edges no matter what, so you're stuck having to define the edge with a cut or some other operation that forces the edge to be visible.

If you have to triangluate the model for some weird reason, you can apply a "turn to poly" modifier, turn on "Limit Polygon Size" set the "Max Size" to 3.
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polycounter lvl 10
Normally what I do to triangulate a mesh: Convert to patch > convert back to editable poly. Bam.
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polycounter lvl 12
Prophecies , thats what i do also
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mod
With it as a modifier, you can remove it at any time and it goes back to being quads. With the convert method, hopefully you don't save it as tris, or you remember to undo it after you've exported.
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polycounter lvl 9
Vig wrote: »
With it as a modifier, you can remove it at any time and it goes back to being quads. With the convert method, hopefully you don't save it as tris, or you remember to undo it after you've exported.

it also has a function to get rid of mid edge verts which is soooper usefull.
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polycounter lvl 15
Prophecies wrote: »
Normally what I do to triangulate a mesh: Convert to patch > convert back to editable poly. Bam.

Try converting to an editable mesh, or even adding an edit mesh modifier. Triangulated edges will be hashed out, and you can always go back to editable poly.