What's the difference between UV mapping verse unwrapping the model UV?

[BNG Da BZ Fool]

In Truespace, I can apply the standard UV mapping modes, i.e., cubic, planar, etc. TS, also allows the model to be unwrapped as well. One method describes using it's UV slice tool to select edges prior to unwrapping the UV, and the other describes deleting a single face from which to unwrap the UV as closed objects are not supported. As I understand them the first method uses the user selected faces to begin the unwrap while the second method uses the deleted face from which to unwrap the model UV.

The standard UV mapping results in multiple overlapped UV lines in the resulting map while the two other UV unwrap methods result in a clean UV map free from overlapping UV lines. The unwrap methods remind me of doing something like peeling a banana with this representing how a model is processed via the unwrapping tool in TS and then evenly spread out on a flat surface. How does this work in other modeling programs like MAX? Is it easier to just unwrap the model verses trying to paint a model skin using a standard UV map? I really want to learn to paint model skins, but I'm looking for the best way to get a decent easy to paint UV into my paint program.

I've been working with Paint.Net and another one called Arcsoft Photo Impression 4 both of which support adding new layers and support TGA files which support alpha channels. Paint, lacks a true airbrush tool, but can be faked by setting the transparency controls to less then 100% to make it paint with a feathered effect. As I understand the original layer is mainly used as a template guide to paint new layers with the actual model skin. Should I use multiple layers rather then trying to paint everything on one extra single layer? Is 50% transparent more or less the ideal level to set for each layer I add? Tanks, BNG.   

[BNG Da BZ Fool]

In this photo I used the UV slice tool to slice a single straight line to get the resulting unwrapped UV map. Notice how not one UV line overlaps another? Just what a simpleton like me needs to paint a decent UV based unit skin. I was also figuring out how to duplicate and add new layers to the outputed TGA file. I kind of need some help on figuring out how to proceed from this point? I adjusted the opacity on the second layer to 50% so I could still see the UV lines from the first layer. Should I just start by using the bucket fill tool to create a solid color? Any assist would be appreciated on what to try next. Tanks BNG.

[mrtwosheds]

Personally I would find a nice base texture somewhere, Just about all of my dalek skins were created from 1 brushed steel texture I found loitering on the web, This gives you somewhere to start from and also gives an appearance of continuity between different units. Add a bit of bevelling, shading, colour, detail, lights etc etc guided by the uvmap and then see what it looks like on the unit.

[BNG Da BZ Fool]

Cool, starting with a good base texture sounds decent. I have a preferences for standard camo based textures with enhancements of course to key areas on the model perhaps I could try this with a second layer where the opacity is set less then 100% (say something between 80 to 90%) on a new layer with the enhancements primarily on the new layer essentially leaving the original camo texture basically untouched. Very cool I'll give it a whirl and see what results. I'd like to create a good overall texture with a mix of desert and Forrest colors to make a general purpose camo texture suitable for most environment types; sort of a light/dark mix where camo textures where originally designed to break up the outline of typical combat units in the field. Tanks, keep the suggestions coming guys.

[BNG Da BZ Fool]

So does beveling refer to visually painting the edge of something to give the bevel effect? I really never gave it much thought, but I guess the model skin maker would want to try to make essentially a flat picture and do stuff like this to simulate a more 3 dimensional surface. It sounds like modelers need to spend a bit more time on skinning then the time it takes to actually create the model geometry? I have a ton of models without textures, so I guess I better get cracking on learning how to master my paint program just as intently as learning to use my 3d modeling program. As critical as skinning is from what I've heard a few more texture painting tutorials should be posted for all to see and use. I may attempt one once I begin to make heads or tails out of things related to painting a model skin. I've taken a first step and posted some questions on the Paint.net community forum about skinning stuff like models and props. I've also begun posting at Caligari's forum with questions about TS 7.6, but that's a whole nother en-chee-la-da. BNG.

[Avatar]

First of all, take a look at the unwrap you showed:



Notice how each face is distorted?  Stretched or skewed?  This is going to make creating a decent skin from an unwrap like that very difficult...   Utilities like Lithunwrap take care to represent each face accurately, or at least all scaled the same...

Now, you could apply a 'face' UVmap, or whatever Truespace calls it when it fits the map to the individual faces, and then move them around one at a time to make a true map of the faces of an object, but MAN is that a lot of work for very little payback.

So, IMHO the answer to your original question is you START with a 'close' UVMap applied to the object, and then you move on to UNWRAP the UV Map in sections to adjust it to the texture or object.

I've found that the easiest thing to do is find a mapping that gets close to a true representation of your object, and map the entire object with it.  For example a wide, flat vehicle is just begging for a PLANAR map, while a rounder, longer one would suggest a CYLINDRICAL mapping.  You get the idea...  This gets you close but not perfectly mapped.

Then, one section at a time, you select groups of faces and adjust/move them to various areas of the texture either to fit the texture you have or act as a guide to creating the texture you want.

A good shortcut is to try to make your mapping as symmetrical as possible, then fold and weld your mapping into a smaller area.  Let me show you for your sphere as something like that is just begging for it...

Starting with your sphere I apply a "Spherical" UV Map to the entire object.

Then I hit "UNWRAP UVW" to unwrap it.  Here's what I get...  which while not accurate in size and shape of the faces maintains symmetry and 'adjusts' the faces the same for easy manipulation:



See how nice and symmetrical it is?  That just begs for folding/mirroring...  Select one half of the verticies and hit 'horizontal mirror',



then drag them over the other half:



Now do it again vertically:



Now making 1/4 of a texture will map the entire object, leaving you with lots of room for other parts of the model or more detailed sections.  Another alternative is to expand the 1/4 sized map to the size of the entire texture, giving you more detail than you'd have otherwise.

The main drawback to this is that adding text will give you rotated/mirrored text, but those individual spots can then be selected and flipped to make them display correctly.

So, the quick and easy 'cylindrical' mapping gets you almost there, flipping/folding the map gives you other options or more detail, and individual faces can be selected at the end for 'fine tuning'.

-Av-

[BNG Da BZ Fool]

Thanks, AV. Understanding UV stuff has me somewhat stumped, but as I just start playing around with the mapping options it's slowly sinking in piece by piece. I see what you mean about the unwrap I posted. When I did get it into my paint program I didn't even know where to start or what was what. The planar type seems the easiest to recognize and work with. BNG.

[Avatar]

To be honest planar is my favorite to start with...  Most ship models I do have a certain symmetry and are generally wider than tall, longer than wide, making them pretty perfect for planar mapping.  You can do a decent map that way, and then select any stretched side pieces and remap them individually.

Part of the trick to mapping is to make it as easy on yourself as possible, or you'll quickly become bogged down in fine tuning the mapping and run out of steam...

-Av-

[BNG Da BZ Fool]

One thing I realize for sure is that I really need to focus quite a bit more attention on mastering the TS UV tools to learn what I can do and not do. TS 7.6 uses a new UV map module quite a bit different from the included older 6.6 version UV mapping controls, but I need to learn to use them both as the newer version supports several UV unwrap options for creating flattened layouts in th UV editor workspace. I haven't even really touched the 7.6 version yet as 6.6 is what I'm already used to based on the work I did with Gamespace Lite; now obsolete and no longer available. Thank God for simple 3d modelers like Truespace, otherwise, I'm afraid I wouldn't have ever been able to figure out how to use the other much more complex 3d packages currently available. My focus is going to zoom in on UV mapping as I already know how to make models from scratch. BNG.