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call4jim
11-02-2009, 12:38 PM
Theres some things I not sure about when modelling. I tried looking up and haven't really got an answer, and if there's a thread that answered this question, then I'm sorry I must've mist it. I imagine a lot of this will be just use my judgement but I just like to double check

Topology I think that's the word. I know people model in triangle and squares, isn't referred as Tri's and Quad's. I know Tri's are used in games and quads for everything else that I know of at least.

So if I want to model for games I do Tri's or I guess model in Quad's then convert to Tri's s that ok?

I'm told to keep topology all Quads or Tri's just wonder what does this generally effect?
If I model generally anything else in Quads does having Tri's in some areas effect anything just I seen a few wire frames pictures and say a face its a Quad model but there's a few Tri's on the centre line on neck and forehead?

I also like to know about using multiply meshes for 1 object. So example a simple table a board a 4 legs. So is ok for me to just model the board and legs as 1 mesh or just make a board and 4 legs giving me 5 or is just because its a simply table it doesn't matter. I guess this applies to most furniture like shelves and cabinets.

What about a bed or sofa there's a body frame and there's a matrices, or not that important, if its low poly?

I know for things like a car or anything that articulates you got no choice but to make extra parts like the wheels and doors. I mean that would be insane to try to make it out of 1 mesh.

Character modelling. I know games make there characters with clothes as 1 mesh, and I imagine small companies do as well. Kind of in the wrong area for this but who/where do you make character with ncloth then a major film company?

Thank you for any advice

Piflik
11-02-2009, 05:06 PM
For your topology questions have a look here (http://www.guerrillacg.org/home/3d-polygon-modeling/subdivision-surfaces-overview) and here (http://www.guerrillacg.org/home/3d-polygon-modeling/subdivision-topology-artifacts).

You can model in Tris, Quads or any type of Polygon you want...internally they are made from Tris. Always. Everywhere. Since game models tend to be constrained when it comes to facecount, the internal triangulation might not always be the way the artist wants it to be and might screw up the silhouette of the model. Thats why, for game models, the artist cuts the Polys into Tris himself.

Whats more important than 'AllQuads', is to have consistent Edgeloops, and to achieve this, it is perfectly OK to sacrifice some Quads. If you want your model to be animated, but the edgeloops don't allow for it, your screwed ;) (the edgeloops are one of the reasons, why some modelers tend to sermonize the 'ALLQUADS' rule...the other reason being SubDivision Modeling artifacts with Tris or NGons).

If you model your objects in parts or as one single object is for you to decide. What looks good, looks good ;). One thing to note however: If you model your table in five parts (or attach these parts together without welding vertices), you will most definitely have some overlapping, to make sure there are no gaps. This will lead to wasted texture space (since these invisible parts need to be unwrapped, too) and if you are constrained to a certain texture space, you might want to minimize the overlapping. But if you have a facecount constraint at the same time, you'll have to find a trade-off between texture space and facecount (since welded parts need more triangles than overlapping parts).

Clothes are mostly simulated to get good, convincing results (the big apps all have some tool to simulate cloth, so there is no need to buy expensive third party plugin...). When you export it to a game engine, you might have to make it with bones, if the engine doesn't support vertex based animations.

Hope I didn't kill anyone with this wall of text...

call4jim
11-02-2009, 09:41 PM
Thanks for the videos

From what I gathered and feel free to correct me. Though modeling in any polygon form isnt much of an issue, quad seems to be the most effiicent and s should avoid having more or less 4 sides a vertices to have a smooth edgeloop. Though its ok somethings it really depeneds on if its being aniamted. So just try to do quads as best i can to save hassle?

About modeling multi mesh etc. So its ok to have multiple parts again example table 4 legs, but it order to not have gaps the legs will have to physically shoved into the board causing an overlap, which leads to texture issues, while modeling 1 mesh means more face count. well a cube of 6 face and a 4x10 face cyclinder is alot less then a having to 4x10 faces into the board. I undersand face count restaint, and I do understand the term of constrant of texture space but I dont understand how its important, I can kinda guess it means more and larger texture leads to more render time but please explain it as I dont really know.

So cloth is something that makes well clothes and other cloths look more belivable. But generally speaking not something I should have to truely worry about if its not my thing or just beyond me?

Thanks for the advice so far, its really helping

gsokol
11-05-2009, 02:57 PM
call4jim:

Quads are a good way to go. When you get polygons that are 5 sided or more, then the triangulation will be a little unpredictable, and although everything gets turned into tris, making some programs do it themselves without knowing how to do it can lead to problems.

For the multiple objects intersecting question: that is fine to do typically, but it is done more often in low poly modeling for games and such than it is for high resolution models.

And for textures: You guessed right. Textures and lighting are the 2 resource hogs for rendering. Being optimal with your textures will ensure a better rendertime, and will make real time applications run smoother and better.

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