Modeling and texturing for games.

crasong

So I'm new to texturing, all i know is modeling, and even then I'm not familiar with modeling for games.

So here's what I think I know(after as much reading from google as possible).

1.Modeling should be kept in quads or tris.

2.Texture maps should fit everything or as much as possible(in relation to characters)


And what I've been doing is modeling most things in one mesh(bad habit?), and my knowledge in unwrapping is still basic at best.

What I'm asking is for examples of good and bad texture maps, what constitutes tidy mapping, and pretty much the do's and dont's.

Thanks in advance.:)

Ark

1. Everything gets triangulated at runtime if you manually tessellate it or not.

2. Yes, the more you can fit on a texture sheet the better, unless your compromising the quality.
Less texture sheets = less draw calls.

I tend to model things as they are in real life. If they have plenty of separate pieces in real life, then thats what i try to mirror when modeling, unless i can optimize by merging the meshes, then thats what i normally do.

If you talking about modular enviroments then it's obvious your gonna be breaking up the scene into many smaller pieces.
Characters i would presume are the same that they get broken up into things like body, clothes and weapons. Maybe someone can comment on the character stuff?

Unwrapping is still probably the most enjoyable part of game dev.

Id say a god UV map consists of maximizing you UV shells and making sure there is less wasted UV space as possible and minimal stretching.

renderhjs

do's:

1. try to hide UV-seams (i.e hard edges, convex corners, hidden spots,...)
2. keep things normalized (same pixel density = texel space for all UV shells)
3. lineup edges or faces if they are close to 90° angles, so pixel borders better loop and connect
4. keep padding space in mind for Mip Mapping issues (because textures get resized in that process and might bleed into other UV-elements)
5. use either square (preferred in most engines) or 2:1, 1:2 ratios (if the engine supports it) of the texture map.
6. Unwrap before you attach instances or elements of the same mesh. That way you only have to unwrap it once if after that its all stored in 1 mesh object.
7. try to combine objects into 1 UV map or texture map if they: Are used always together, are in the same scene. Because not only can it save RAM and render calls in the engine it actually saves also work time because unwrapping one big pile at once is more efficient as several one after the other.
8. Increase UV-shells or parts that need more detailed texture maps as others. Like for example sometimes hands are scaled up in the UV because the game has a camera close to the hands of a character

dont's:

1. Separate every sub object into 1 texture map (i.e head, arms, feet, ...)
2. automate UV packing. At least see yourself what can be changed, moved or tweaked. Also I know many artists that rather prefer to know where they packed their stuff once they start texturing instead of random scattered UV-shells with maximized compression.

ah well I guess there is even more but those are some general things I would consider.
As for tools:
I really can recommend UVLayout from Headus its a top notch professional UV layouter with maximum performance on its design focus (unlike many other tools). Besides that you have RoadKill and Roadkill professional, another UVlayout tool by some french guys (don't remember the name anymore).
And of course any of the major 3d packages and their build in stuff (Maya, max, modo, silo,...).
There are also some scripts and plugins available for most 3d packages that help lining up verts or automate some tasks.

crasong

Hmm, yes I think I can understand the process a bit better now.

Thanks a lot Ark

I'd like to throw in another question or two.

I notice that people make hair sometimes by texturing extruded planes from the head, though i've failed to find any tutorials on this so far. Would anyone care to explain it to me?

and things like armor pieces that are seperate from the character model, do you combine it to the main mesh?

crasong

Ah thx for the quick reply renderhjs!

Excellent community, I can expect to get good crits once i start texturing stuff.

Small note, I've been using Maya for a span of slightly over two years now, but shamefully i've only learnt modeling, and only have basic theory in everything else.

Partly due to me having to self learn, I find myself staring at advanced tutorials that use terminology that I don't yet fully understand.

Once again, thanks guys! Keep up the good advice!

Frump

Here's a pretty good tutorial about hair. Take a look to satisfy your curiosity, but don't worry about doing this until you have already nailed the process of texturing of the rest of the model.

http://www.paultosca.com/varga_hair.html

crasong

Thanks! I will look at this

AnimeAngel

Very nice tut thr. thx

crasong

Hmm. Also, I've found a few pictures here and there illustrating edgeflow in characters for proper deforming when rigging. I could definitely use some advice on that

crasong

P.S I definitely want to pick up low poly modeling, but i still find it hard to go below 1k tri. Any tips on how to approach doing the head would be great.

Really appreciate everything so far guys!