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Things to help make UV mapping easier:
Plan from the beginning to UV map your meshes. If you keep the meshes texture requirements in mind while modeling, you can often avoid UV mapping headaches by not creating them in the 1st place.

Model symmetrically. This will basically cut your UV mapping work in half. Don't make the model asymmetrical unless absolutely necessary. This way, half the model can be UV mapped, then mirrored. Once UV'd, the mesh THEN can be made asymmetrical, if needed. and quite often with little or no UV re-work. (Caveat... this technique doesn't work so well with meshes requiring normal map or lightmap baking which requires the symmetrical UV islands to occupy there very own UV space. There are workarounds, however.)

Don't make the mesh distorted when it doesn't have to be. You can always distort it AFTER UV mapping. (e.g. Your snail... model him "straight" from stem to stern, UV map, THEN, raise his head; model a single "eye-stalk" straight, UV map it, copy & mirror to the other side, then distort.)

Remember that mesh data with UV''s, when copied, takes it's UV's with it.

UV seams, if at all possible, should be scaled flat in either the U or V (x or y). This makes matching the texture across the seam MUCH easier. Once you flatten the border edges of a UV island, keep them selected in the UV editor (also keep any other UV's you wanna keep in place selected), and R-click -> re-map. Selected UV verts are considered "pinned" when you call "re-map" so they will remain in their current position and the distortion caused by flattening them will be propagated across the rest of the UV island.

If flattening UV borders creates too much distortion, then be sure to make your UV cuts in places that are normally (or most often) hidden from view. Also, make cuts anywhere there is a change in the basic material. This seems like a "no-brain-er", but I've seen people try to UV map everything in one big lump. Also, if your model has cloth/clothing... cut UV seams where the cloth would have seams in the real world. Cloth looks more realistic if it has seams where it SHOULD have seams!

Do NOT scale up individual UV islands for better resolution when they directly border on other (lower res) islands. This will create a very visible seam that is impossible to hide without using multiple UV sets... which Wings doesn't support. I've seen many novice modelers try to scale up the face UV's for more texture res, and then wonder why they can't get the face to neck texture seam to go away. In this instance, if the neck (skin material) disappears into a shirt (different cloth material), this provides and natural place to cut the UV's...then, you could scale the entire head, neck included, and the transition from high to low res won't be as noticeable due to completely different materials.

Barnoe
You really can't compare texture rendering in SL to anything else... SL is the "Blender" of game engines... totally different from all others... well... it's more like a Martian version of Blender.
I've built models for a LOT of game engines using Wings, and teh UV mapping is pretty much 1:1 with the plethora for engines I've used (w/ Wings: Gambryo (Renderware), Quake2 (modified homebrew), Unreal2, Ogre, CrystalSpace, Irrllicht, Unity, BlenderGE, Torque, Reality Factory (Geneisis3D), Jet3D, Destiny3D (defunct - main dev now works on DX team at MS.), just to name a few.

Yes, textures will distort when you deform the mesh. But deform the mesh, and the UV's will be harder to deal with... as with nearly everything in 3D, it's a trade-off.
Most of my meshes (characters) are destined for skeletal deformation... texture stretch is expected, always. How much is basically a factor of mesh density. The more verts the distortion can be spread across, the less obvious the distortion.

Your tablecloth issue is 2-fold...
I think the main source of your distortion is the 5-point pole (one vert, 5 edges) centered right where the distortion is greatest. In other words... the UV distortion doesn't look to be caused by the bending of the cloth mesh over the edge of the table, but by the smoothing algo's effect on the UV's at the 5-point pole.
Secondly, applying the UV's worked great for 90% of the job... that last 10% is for you, the artist, to fix... in my experience, the amount of work it takes to fix "over distortion" is usually small compared to the amount of fiddling required in the UV's if the mesh is "pre-distorted".

That small amount of distortion can be easily tweaked out of the UV mapping.. it will still be distorted a little, but real world checkerboard prints aren't perfect either... one of the main things that make CG standout as blatantly CG are the lack of small imperfections... no loose threads, no misprints, etc. Find a tablecloth that has that type of print on it, put your eye down close to the able so you can look down a line of the checkerboard and you'll see that not a single line is straight... some are woven or printed crooked, some are crooked due to the cloth being stretched, or slightly bunched up at various points, etc.

Another issue is your pipeline... your UV mapping and materials are being done in one app, and your rendering in another. This is why I haven't used Wings to do anything more than very basic "1st pass" UV mapping for quite a while. I UV map and apply materials/textures in my rendering app whenever possible (These days, that would be Blender). That said, Wings' POV exporter has the ability to smooth on export (in the POV export options dialog... set the subdivisions slider to the appropriate level of sub-d., so you shouldn't need to keep a Wings "hi poly" data set. You should be able to smooth the mesh in Wings to check the UV distortion post-smoothing, undo to un-smooth, tweak the UV's, check-smooth again, ...lather, rinse, repeat until you're happy, then undo all smoothing in Wings, and export to POV with smoothing and save your Wings files as the lo poly version and your POV files will all be hi-poly.

Here's a quick scene I did in Blender to show ya how I would do the table cloth.
It took longer to create the texture than it did to setup the scene.
The texture is 512x512.
It is tiled 4 times in each direction.
It not only serves as a diffuse color map, but is also set to slightly effect the mesh normals as well to give the mesh slight cloth-like bumps.

The "table" is simply the Blender default cube.

The table cloth is a plane, subdivided twice (non-smoothing subdivision... really, just a "multi-cut" op to add some faces for what comes next), then 4 new edge loops cut in and moved to very near the outer edges so it holds its shape when a sub-d modifier is added.

The low res mesh is UV mapped using a simple "project from view" op. This took, literally, 5 seconds.

A C-C sub-d modifier is added, set to 5 iterations to create a fairly dense mesh. The "sub-divide UV's" option is selected, minimizing any UV distortion caused by the sub-d smoothing.

I then ran a cloth sim for about 40 frames to let the "table cloth" settle on the table (sim took ~ 15 min's), then applied the cloth deformation to create the shape.

A quick pass with the sculpting tools to smooth out some problem areas left over from the sim.<

And this is the result:


I used the Blender internal renderer, with 1 spot light (for key light) and 2 point lights (as fill lights), none casting shadows.
I added Raytraced Ambient Occlusion for the "shadows".
The original render took just under 13 seconds on a P4-HT 2.4GHz w/ 1GB DDR RAM. (my 5+ yr. old machine here at work) at 768x432 (40% of full 1080p HD).

You can see some glitches here & there, but if I wanted to spend a little more time on it, they could be easily fixed.
There is some texture distortion, but it follows the distortion you would normally see in cloth drapped over a table... nothing too drastic.
From start to finish, including texture creation, it took about an hour, mostly fiddlin' with the main "bend" with the sculpting tool so the table didn't poke through.

Yea... Blender looks scary at first, but really, this was so simple and most stuff required very little fiddling & used default values.
For instance, the cloth sim...
All I did was enable collision for the box with default settings (one click)
Enable cloth on the plane, and use the "Cotton" preset from a dropdown list in the Cloth panel. (2 clicks)
Hit ALT-A to start the sim... hit ALT-A again to stop it at 40 frames.

I had my basic cloth shape.

Only the key lamp ( the spot) required aiming.
But the other settings of the spot lamp were default.
The other 2 lights were points so they only required positioning and setting the intensity to 0.5 (default is 1.0)
They didn't even cast shadows so there was no fiddling about with how the lights generated shadows (# of samples, # sample buffers, & all that other fiddly crap)

Enabling raytraced ambient occlusion is one click with defaults.

The new 2.5 interface is pretty easy to use, really... compared to other full-featured 3D apps, it's really no harder to learn.

Anyway... the whole point was that the cloth was mapped "in the flat" at low mesh resolution, then deformed, with what I think are acceptable results.

Yes, the mesh is dense, and it would bog Wings down... (5 iterations of smoothing... that's over 170k polys with the lo-res mesh I started with), but this mesh isn't a problem for Blender at all.
And mesh density was a factor of how I got the shape (cloth sims need lots of polys to "fold & crease")... not the way it was UV mapped.
I used that method because, for me, it would have been faster than trying to model it directly... again.. the "trade-off" was time vs. computer resources.
Had I been forced to do this in Wings, I would have HAD to model it directly.

Wings3D is my tool of choice for creating the base meshes for later sub-division... but Blender is where they end up for everything else: UV mapping, texturing, hi-res detailing, & rendering... either with Blender's internal renderer, or one of the several 3rd party renderers that have export scripts available for Blender. Wings+Blender gives me nearly everything I need modeling-wise... the excellent polygon modeling tools that support n-gons of Wings + all the curve based modeling methods offered by Blender's modeling tools, powerful array tools, and a powerful material/texture system.

I didn't start using Blender in earnest until a couple years ago. And it really didn't take but one or two projects using it to really come to terms with stuff you'll use most often. And, if you're not doing character animation like I am, what you have to learn is even more compact. I mean... you can always learn to use Blender's rigging & animation tools at some point, but it's hardly necessary if you're just creating some nice still shots. I have no doubt that if you started using Blender in earnest to setup your scenes, and just use Wings to create assets for those scenes, you would have the basics of Blender down in no time.

Dude... I've seen your models... you can create VERY nice models in Wings. I think you're doing yourself a disservice by not getting them into a proper scene for nice still rendering. I've used POV in the past... I KNOW how fiddly it is, and how, because every little parameter isn't covered in the exporter, you often end up tweaking stuff in a text editor... to me, that's a "turd in the hot tub" for my creative "flow", if you know what I mean.

In fact...
If you want to send me one of your Wings "scenes", I will set it up in Blender and give it a shot. If the meshes are un-textured, no problem. I'll either texture them, or set the scene up as a "clay" render.

I will send you the full HD res image, and the source .blend file (packed with all used textures) in case you want to d/l the new Blender2.5 Beta and play with it yourself.

Randy[dot]Fugate[at]gmail[dot]com

digitali wrote:

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Um...just can me digitali, I'm from Jamaica and I'm new to wing3d. I have to admit that it iss every easy and I have done great 3d modeling but, I'm not good at UV mapping and texturing. Does anybody have a toturial video or a toturial video link that could help me?

Lots of good Wings-specific info right here in this forum in the AutoUV Project section..

http://nendowingsmirai.yuku.com/topic/2136

Google UV mapping tutorials for general info on UV mapping... and LSCM mapping in particular, which is what Wings uses to unwrap.