Multi Chan Hax Head

From TechSlop

I've been talking an awlful lot about mapping channels lately and I've been rather quick about it. I realize that some folks don't know what they are or what they can be used for. So I'm going to slow it down just a tiny bit with an easier example than what I've been showing.

A mapping channel is basically UV data. It's how a 2d texture gets translated onto the geometry of a 3d model. If you have access to one of the higher-end 3d software packages, chances are good that it supports mulptle mapping channels.

See those wire frames? Those are all mapping channels. You have the head template provided by Linden Lab(R) for the game Second Life(TM). Also a wire frame for a front head shot and a side head shot.

The really cool thing is that all of those mapping channels exist within the same model. You can actually take one of those channels and move things around to another channel. This is so uber for texturing. Don't like the way a little something is mapped? Remap it in another channel. Seams getting you down? Remap the seams in another channel.

This is Camille from Spectralogue. At least I think that's who it is an where she's from, but I can't confirm right now. But I do know for a fact that these images can be used here.

The original photos that I grabbed are actually kind of big. I sized them down and put the two working images side-by-side because I'm not in the mood to show every little thing super huge. But know that my actual working document is 512x512.

Using the wireframes, I got her mostly fixed for the templates using Free Transform. But that wasn't quite enough, so I did some Liquify to distort her a bit for a much better fit.

Notice that I didn't bother with the ears in the front shot. Only the main of the face is important because that's what that particular channel is for. That is, I'm not going to be texturing the ears using the front shot so I'm not going to bother.

One thing that I made sure to do is to extend the fleshies out past the wireframe just a tad. There is the transparency thing and I didn't want the background creeping in too much when I get to moving things around with Multi Chan Hax.

Now both are ready to go with some mapping channel action.

But there is something that I need to tell you about first. The MCH file that I'm using does have the SL default, front, and side. However, there is another channel in there. I snuck it in real ninja like just in case I felt like using it.

Channel 1: The default SL head.

Channel 2: This is the extra channel that I snuck in. It's more of a regular sphereical UV mapping that is quite common with a lot of head models. The ears are bunk, but it will serve it's purpose just fine.

Channel 3: Front.

Channel 4: Side.

One of the weird things about me is that I'm easily confused by certain little things. Even though Multi Chan Hax has sliders for independant channel picking, I left the Reverse option in there. Even though I know which channels that I want to use, I can never keep straight which way I want to go. So, the Reverse option keeps me going rather quickly without having to think too hard.

So, fired up Multi Chan Hax, loaded up SLF_head01.mch, used channel 1 and channel 3 (front to default), and let it rip. Maybe I used the Reverse option, maybe not. Don't know, but it's there in case you have the sliders reverse as I often do.

And this is what gets spit out:

Once Multi Chan Hax has done it's thing, there is transparency to deal with. I used one of the Solidify filters by Flaming Pear. There are other options for filling in transparency, that one is usually the quickest.

Notice that the face also got translated to the back of the head. This is because I did a regular planar map using the front and didn't bother taking out the back of the head when I did so. However, I was smart enough to take the back of the head out of the template. If I had left the back of the head in the front template, it would be almost unusable mess of lines. Don't worry about the face being on the back of the head because that can be sorted out later.

And then do the side using channel 1 and channel 4 (side to default).

Pretty spiffy, eh? Notice that in this channel translation that the hair on the back of the head will nicely over the face that's back there from doing the front. Even so, it will probably get painted over or texture fixed later anyways - it's just a nice little thing to note.

So finally, layer over layer and some really quick-n-sleazy Layer Mask action:

And here I started fixing it up. Just gave it a quick once-over using various techniques. Even did a tad of mirroring.

Not really in the mood to go much farther because this is more about how Multi Chan Hax can be used instead of fixing things up (retouching and texture work is a whole new can of worms).

And there is a quick preview using SLCP by Johan. In that shot, the left jowel looks all jacked up, but it actually isn't. That's just the way SLCP renders it at that angle. As soon as I rotated, that big nasty blotch went away.

For the MCH file almost identical to the one in this tutorial, see Multi CH Repository. It has been updated and does not include the crappy ninja channel. Since that channel was taken out, the numbering of the channels is different than what was said in the above. I will fix this to reflect one of these days.

Multi Chan Hax

Oh, I almost forgot to mention Big Data. When move layer stuff around in Photoshop and part of the layer goes off of the canvas, it is actually still there. Multi Chan Hax will operate on the Big Data. If things are suddenly out of proportion, good chance that it's Big Data. Either select the entire canvas and then do Multi Chan Hax, or crop the entire document to completely get rid of it.