I'm working on some clothing, and I want the forearms and the upper chest to show up under the mesh. The way I've done this is to put some alpha sections on the sleeves and bodice, and then paste the .nif of a female upper body into the model. It shows up great, but I have some issues with clipping when the character does things like spellcasting and such. My solution for this was to put alpha sections on the skin texture as well--particularly the upper arms and the stomach, which are the parts that are clipping through the clothing.

This worked... except now whenever the character is indoors, her skin turns a really dark shade. I've narrowed this down to the alpha property on the upper body nif--if I disable alpha blending, the skin color properly reacts to different lighting conditions. The clipping then returns, of course.

If I could just snip off parts of the arms and the stomach from the upper body nif, that'd be best, but I don't think I can do that with nifskope, and Blender is beyond my pay grade.

So barring that, is there any way to use alpha on the body without having the shading go haywire?

Best solution s to just have all parts rigged correctly to prevent the clipping and use alpha only on the parts that need it. Can you post screenshots of what you are trying to do?

If you at least have Blender, you can get it to do a lot of the work of avoiding clipping by copying bone weights from the body mesh to the armor mesh so that they stay together. There's a script for that.

Sure. Here's a nifskope screenshot.

http://img19.imageshack.us/img19/7563/empressrobe.png

I started with a modified imperial robe mesh that someone made for female characters. Then I put alpha on the sleeves and the upper chest, as you can see there. Since the robe wasn't met to cleave to a body mesh, I had to shrink the mesh to make it fit. There's significant shoulder clipping in nifskope, but because of the way the body poses turn out in-game, you don't see any clipping of that nature unless I am using restoration magic--at which point the shoulder clips out of the robes arm sections when the arm is lifted up.

I don't have Blender, though. Does it have a free trial or something? If I got a hold of it, what are the steps I would need to do in order to copy these bone weights? That doesn't sound tooooo terrible...

Blender is totally free. Just download a copy and use it. It does have a steep learning curve, especially if you learned another tool and have to rethink everything, but it's not hard to learn to do the few things you need here.

Bone weight copy is as simple as 1) select "from" mesh, 2) Select "to" mesh, 3) Launch copy script, 4) select level of fidelity, 5) wait a while so it can calculate the new weights.

The mesh you're copying to cannot have any existing weights, so you might have to clear those first, which is a bit more laborious, as you have to delete the weighting to each bone in turn, but it's simple to understand. I do this mostly with a freshly imported mesh from another tool, which doesn't have any existing weights. Come to think of it, you could export without weights and reimport to clear them all at once if it's faster.

My standard process for making clothes/armor is to model in 3DS MAX (gmax is a free version of the same software) and export without weights. I then import into Blender and copy weights off a standard unclothed body mesh, so that the neck, wrist etc. have the same as the adjacent body parts. That's just because I learned to model in MAX and Blender's UI is so different. If you don't have to unlearn anything, you can do it all in Blender (did I mention it's free?) Blender also has the better support in terms of import/export scripts - but some of that is because my copy of MAX is a very old version, and it costs a fortune to upgrade that.

If you have the model in MAX or Blender, it's worth deleting the parts of the mesh that are covered, just because it reduces the size of the .nif file, which makes it faster to process the rendering and animation. Polygons that aren't there don't even have to be ignored, and they can't poke through anything either, so errors in weighting won't show as much.

Blender has all the power that 3DS and other programs have, so you can do just about anything you need in it. It also has an active community for plugins. It's good enough that Bethesda could have used nothing but Blender for the whole of Oblivion. Like ghastley has said about learning curve, it is rather daunting to look at. But if you really anolyze what the buttons mean and how they are organized, you'll learn more quickly. Look up Super3Boy's tutorials on Youtube. Best place to start out, I'd say!

It's free, by the way.

Oh, I can delete parts of a mesh? That might be the easiest thing to do, rather than messing with all this business about weights (which looks intimidating to me, frankly). Could I just import the upper body nif, delete the shoulders, and then paste it back into the nif in my outfit? Is importing automatic?

All you'd have to do is pretty much select File>Import>Gamebryo(.nif), select the upper-body mesh, press Tab to go to edit mode, select the vertexes you want to delete, then Tab to get out of edit mode.
Then just select the entire outfit and upper body together, and export.

How do I select the vertices? I can see the model here, in black and white, and this little square thing with a bunch of circles in it. And when I import, I should import everything?

Right-click to select individual things. Select your model that way, then press Tab to go to edit mode. You can select vertexes with right-click (or shift + right-click to select multiples), or press B (box) to select multiple vertexes.

Vertexes will show up pink normally, or yellow when selected.

Like I mentioned, Super3Boy's tutorials can take you far in little time.

Brilliant! It worked perfectly. Thank you sooo much.