PDA

View Full Version : Quads and Tris



kevinmcpoland
05-24-2004, 05:16 AM
Okay, first of all, warning! I believe this may have been asked before, but I searched the forum and couldn’t find the answer…

But my confusion is this. I still don’t really get the pro’s and cons of modelling quads over tri’s.

For example, I believe max does everything (but I could be wrong) in tri’s, and some of those models look/render and animate with no problems. So why does the LW advice lean towards doing everything in Quads?

I guess some of my confusion comes from the tools LW gives. E.g., In Dans LW 8 Killer Tips (great book!!), Page 80 talks about using the bridge tool to bridge quads, in effect making them tris’s, and the demo model is a head (organic). I though the rule was to try and stick to quads, and if so, splitting quads into tri’s would be a “less preferable” option… (I appreciate the model may have been purely for demo purposes, and this may be my problem of looking too deep into things!)

But what about structures, from buildings to vehicles. What is the problem with tri’s in these.? (And if memory serves me right, doesn’t FPrime prefer tri’s aswell?)

I seem to spend so much time trying to count points and manipulate everything to stay as quads, I’m wondering the real benefits…

Thanks for any insight people, and please accept my apologies if this topic has been done to death before…

Kevin McPoland

Elmar Moelzer
05-24-2004, 05:53 AM
Hello!
Well, there is nothing wrong with tris if you are not using Subpatches. Only when modeling with Subpatches you will want to use quads. Subpatches are highly dependent on the edges of the control- cage. You will want the right amount of edges to define your mesh. Four- sided polygons usually provide the best results. With triangles and Ngons you can get some pinching effects.
Also some of LWs tools work best with quads (bandsaw, spinquads etc).
CU
Elmar

theo
05-24-2004, 06:21 AM
Absolutely right Elmar- Quads are synonymous with subpatching. You will use tris with subpatching but at a minimum and usually only in detail areas.

Building with quads is just flat out more manageable. And even if you plan on converting to tris the mesh development process using quads allows you to fine tune horizentally and vertically with much more precision.

I personally would encourage you to stick with quads Kevin. There is a huge place for tris but quads are the undipsuted leader when it comes to mesh development. The quad subpatch automatically gets changed to tris anyways in Layout when it gets rendered.

And why, my dear little man, would anyone use tris on buildings or large quantities of flat surfaces? Because they are prone to sadomasochism- that is the only reason I can think of.

meshmaster
05-24-2004, 06:32 AM
most people do eventually go subpatch on characters... so it's good for them... BUT only if you are not putting those characters out in to a game engine, where tris are necessary... sure you can do the tri conversion from the quads to get the characters in to the engine, but doing so will massively increase the poly count, which your programming friend creating the game engine will not like much... it's better, if game engines are your final output, to build in tris as you go... Also, if game engines are your output, make sure that your texture maps' use pixel sizes that follow the power of twos rule... i.e. 2, 4, 8, 16, 24, 32, 64, 124, 256, 512, etc. Direct X does not like other sizes... it'll use other sizes but you'll get some render errors probably.

theo
05-24-2004, 07:12 AM
Yes, right on Meshmaster- I almost put a caveat in the my last post due to the gaming side, but decided not to since Kevin did not mention anything about games.

kevinmcpoland
05-26-2004, 06:43 AM
Elmar, Theo & Meshmaster,

Sorry for the delay, but just wanted to say thanks for the insight, it's all understood now.

I try to show appreciation as soon as a reply is made out of courtesy but I missed this one, and don't want you to think I wasn't grateful!

Kevin McPoland :D