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Jay Zaine
03-11-2011, 01:17 AM
Hey all.
Just a question that's been kinda niggling at the back of my head.
When your modelling, say a cupboard such as the one on page 59 of S1PartB which naturally has very flat sides that dont require much detail; is it better practice to split the large, flat sides into quads just for the sake of it?
This obviously doesn't extend to more organic shapes like people but crates, cupboards, walls etc

I guess what im asking is, should you ALWAYS work in quads even if it wont add anything to the overall model and if so, why?
I know it says quads, quads, quads but how is it helpful to split up a large flat side of something just so there are more "regular" quads on the model and up the poly count?

(another example would be the columns on page 15 of S1PartC - They have been split 4 times along their height but this wont add any detail to the geometry and there doesnt appear to be a need texture-wise)

Thanks peeps.

JasonP
03-11-2011, 09:35 AM
Good question - As ever with games art there is no absolute correct answer.

If you are doing a game for a low resolution platform (iphone wii DS etc) then you'd keep it as a large polygon to save on overall polygon count.

However if you are working on an xbox or PS3 or PC type game there are advantages to splitting it up. These are that by spltting the quad up there will be more vertices for the game engine to use when calculating realtime shadows, or realtime ambient occlusion or real time lighting solutions. It will give better visual results if there is a similar quad density to all objects.

Often if there are no more UV co ordinates or smoothing groups then a few extra quads within that quad wont make a significant saving.

In short there are arguements for both and it depends on the engine and what the graphic coders want you to do. For display and portfolio purposes I wouldnt split the quad as you are judged on what you can make within confined polygon boundries.

hope this helps

Sajon
03-11-2011, 12:20 PM
Hi Jay Zaine,

I haven't got as far as looking at the course materials you have referenced yet but in my knowledge of quads there are a number of reasons for their use

It is a very good habit to model with quads, if you regularly try to model with quads and keep the model "tidy" it will be easier to manipulate, sub-divide, create good edge-loops, and will give you a geometry that will deform well when animated.
Another important role is that of creating high polygon models, using / adding loops to constrain the low polygon mesh for smoothing.

And although it is not what quad topology is used for initially if done well it can considerably speed up the UV Unwrapping and texturing process when everything is part of defined 4 sided quads.

if you look at this video of a Colt M1911 I made you can see the wire frame after a few seconds and see how it is all quads. There was no need for a huge tri count just because I kept it tidy http://www.youtube.com/watch?v=0f8t4pMp638&hd=1

Hope I have helped :]

Jay Zaine
03-12-2011, 11:40 PM
Thanks to you both.
So I guess the answer is - only if you need them :P
The point about shadows and the like was interesting as I didn't know polys where so important to shadows. Since most of what im making at the moment is more for display purposes I guess im ok at the moment.
Sajon - the gun video was very nice. Good detail on the colt and I really liked some of the spec mapping where there was wear to the paint. Very simply modelled but all the detail needed.
Gonna have to step it up a bit :P