In this series of lessons we're going to take a look at the basics of working with UVs in Maya. UVs and UV layouts are important aspects of creating textures for our 3D models. They let us tell Maya how to apply the 2D images we create. Having a good UV layout can really make a difference in speeding up texture creation and optimizing your results.
In this lesson, we'll talk a little bit about automatic UV mapping. So, we'll use this head model as an example. And you can see that the UVs need a lot of work here. But the shape is such that using some of the simple projections that we've used up to this point may not be adequate. We're going to have to do a lot of editing. So you'll find that, when you go through the process of laying out UVs for objects, anything over very simple objects based on the projections that we had, flat objects, cylindrical objects, spherical objects, anything a little bit more complex than that is going to require some editing on your part. It's just the way it is for the most part if you're going to be adding textures. And so an object like this has some holes in it, it's got some undercut, some areas that stick out more than other areas. And so, inevitably, we're going to have to do some editing. So, a lot of times, and maybe this is just personal preference, I like to actually lay out the model using automatic mapping, and than it just kind of breaks everything apart and allows you to edit those manually. And we'll talk more about the actual editing process and editing UVs more in the next lesson. But at this point, let's just concentrate on the automatic mapping itself. And so what this does is actually use a series of planes to automatically project our model. So we'll take our head, go to Create UVs, here is automatic mapping. So we'll open up the options. The first thing we'll see are a number of planes. So, without choosing anything else, let's go ahead and just project this with three planes. So we'll go ahead and just project. If you move out, you can see, these are the three planes that we're using to project. So it's projecting from this side, it's projecting from this side, projecting from this side. If you look in our texture editor, you can kind of see this, but they're all overlapping. OK. What we want to do is have everything separated out. And you can see here, parts of this look good, although there are seams all over that we'll need to deal with. So let's go back into automatic mapping, and let's go down to one of the options down here, Layout. Right now, the shell layout is set to overlap. What we can do is say, we want to actually lay this out either along the U, or we want to tile it, or into a square. So if we project now, you can see that all of those pieces are separated out. Now you can see why this can be a little bit more work, because we now have to go in, select all of these projected shells, and sew them back together in a meaningful way. So this is a good starting point, but it'll rarely get you to the point where you need to be without any editing. But you can see that the face, for the most part, is in one piece. We can also choose to use a different number of planes. For instance, if we're not getting all of the sides that we want, we're not being able to see everything, we can actually use more planes. So, choosing this, let's go to automatic mapping. Let's change the number of planes to six. So that'll basically have a plane on each side. We'll go ahead and project that. And so you can see now, we're getting a projection from this side, this side, top, bottom, and front, and back. And so here, you can see all of those pieces there. We can rotate those. Go ahead and hit Rotate. Let's get that tool back and rotate our planes here, as you can see there. Rotate those around. We can go back in, we can change our number of planes again, maybe change that up to 12. We also have optimization here. So if we choose less distortion, we're going to have more pieces potentially. If we have fewer pieces, we could have a little bit more distortion because we're making these larger shells. So that's a choice to you could make up there. And you can also, again, choose the spacing between the different shells down here. Now, we've got a preset here. You can also choose how you want to lay these out into this zero to one space or the rest of our editor there. So we can go ahead and project that. And you can see now, we've got a lot of these planes projecting down. And you can see that that creates more pieces here that we can now connect together. Let me go into our automatic mapping here. Normally, I'll use maybe six planes or so, kind of just lay that out. I usually lay it out in a square. If we want to do it along the U, we can do that. You can see it just lines all those pieces up along the U, OK. If we tile it, you can see what that does. OK. And the square separates everything out, spaces it out, lays it out onto the square. So just play around with some of the settings. The main thing that you want to look at all are how you want to shells to be laid out, and then how many planes you want to use to project those shells. OK? And if you want less distortion, fewer pieces, and so forth. And so this looks pretty good, but if you get up in here, you can see well, we've got seams coming in here. And if you look in the actual UV Texture Editor, you can really see those seams. It really is pretty obvious. So the next thing that we want to do from this point, once we've got an automatic map or we've used another projection method on portions of our model and now we need to go in and edit this, we really want to come into our UV Texture Editor and start to put everything together. And that's going to entail sewing pieces of this together. So, where this is connected, where it should be connected, we need to reconnect that and make sense of everything in our zero to one space so that it looks like it's an unwrapped version of our 3D model. And minimize the number of seams, hide those seams where they won't be as visible. Things like that are what we're going to be concerned with. So let's come in in the next lesson and talk a little bit more about editing our UVs. So we'll spend some time in the UV Texture Editor talking about some of the tools, talking about some of the techniques we can use to break things apart, put them back together, and so forth. So let's go ahead and do that in the next lesson.