Overview of Blender unwrapping basics: Part 1 - Blender Tutorial

- So now that we've sculpted the detail into our high polymesh, we've duplicated that mesh into a low polymesh, reduced the resolution of that low polymesh, we're almost to the point where our creature is going to get all that detail onto that low polymesh. But, first we have to do what's called UV unwrapping, and this is a process that's going to take all of the surface detail or real estate on our creature and it's going to flatten it out, so you can think of it as making a suit or a dress in that we're going to start with a bunch of flat pieces that are then going to kind of be pieced together and fit onto our critter. Now, the process can be a little bit confusing, because we're going to go from 3D, which we've probably gotten used to at this point, back over to 2D, so all these 3D pieces are going to be ironed out or flattened out over in the UV space. Well, that sounds easy, but we need to mark all those scenes. So, first let's kind of take a look at how this process works. We're going to start with something easy. I'm going to turn off his head and his hands, and I'm going to work on the body. It really doesn't matter what you work on, you could work on a sphere or a cube at this point, it really wouldn't matter. And we're going to talk about how to set the seams, how to apply the transforms, and how to see what we're doing, most importantly. All right, first thing we need to do is set the transforms for our critter. So we're going to go to object mode for this. And we need to go to object and apply, and rotation and scale. Quick word about this, we've done this before, but everything that we've done to our creature's body or modifiers or all that stuff has deformed his rotation and scale settings. In Maya this might be called deleting history, in Max it's called collapsing the stack, even in Photoshop, this would be the equivalent of collapsing the layers. What we need to do is go to apply, ctrl + a, rotation and scale. Now, it didn't really seem like it did anything, but that's a really important step, because if you forget to do that, everything from this point on is going to be skewed and not look right, and that's because we haven't applied the transform scale rotation. You can do it as many times as you want, so if you forgot if you did it or not, just do it again. I tend to forget whether I've done it, so I apply it all the time to lots of different things. Now, we've got our model, but we can't see really what we're doing in the UV space yet. So, we need two windows open. Think of it as our 3D window and our 2D window. Right now, we've got our 3D window. We're going to go down to this tab, it looks like a little striped triangle, it's been there all along, and you can see them all over Blender. We're going to click on that tab and pull, and it's going to open up a new window. To be honest with you, that was one of the areas that I had the most trouble with when learning Blender, was figuring out how to control these different windows opening and closing, because it's just different than any other program I had used. If you want to close the window, just click on that tab, hold down the mouse button, move a little bit, you'll see an arrow, that arrow is saying it's going to close that way. And then let go, and it sucks it over to that side. Think of it as a sliding door. Well, we've got two windows open, that's great, but they're exactly the same window. So, we're going to go to this button, which we have not talked about before, and that is a little cube with little arrows on it, we'll click on that, and we want UV image editor. By the way, that little button is on all the windows here in Blender. It's right there, it's over here, it's everywhere. It's right there, and so any of these windows can be opened anywhere in Blender. I'm going to hit UV image editor for this particular window, and we should be looking at this flat grid, which isn't very exciting right now. So, I'm going to scoot this window over a little bit, and just get a little bit more real estate for my model. If you have two monitors, you can extend Blender over to your two monitors, and you'll have lots of room at this point. We are almost ready to start UV mapping. So the first thing that we're going to do is get into edit mode. UV mapping only works in edit mode, and all of our controls work in edit mode, so you can camp out and edit mode this at this point for the rest of the models that our creature's made up of. We also want to be in edge mode, which is that button right there. And if you can't see edge mode, it's possible it gets covered up. That took me a while to figure out learning Blender, is that it does cover up some of the buttons, so just move your screen around until you can see it. All right, what we're going to do is just unwrap an easy piece of my mesh. If your mesh has something similar, great, or you could just use the sphere to practice with on this if you want. I'm going to go to my edit mode again, or edge mode, let's make sure we're in edge mode, it doesn't work very well in any of the others, and I'm going to select one edge. And what I'm looking at is where would I cut fabric if I was making this guy a shirt? So think of it as like a paper doll, or that we're cutting out fabric for this guy's shirt. Now, we've got a couple buttons to learn. Click one edge, ctrl will go from point to point, shift adds to the selection, and shift on something that's already selected is going to delete it. So again, ctrl goes point to point, shift jumps the selection to another area or selects another edge, and shift on something that's already selected is going to subtract it. All right, and we can kind of go dot to dot, so what I'm going to do is, just holding down ctrl, and letting that edge just go wherever it really wants to, I'm going to go around to say, there. That's a good spot for the side of what we'll call his shirt, here. And we're going to click down. And we're looking for areas of the anatomy that are good seams, so like the area here, around his hip. And I think that was one too far, so I'll shift + click on that, and... Had the wrong button there. Shift + click there. So, shift, I'm selecting a new edge, ctrl, I'm just letting the edge run to wherever I click, and a lot of times, most of the time, it works. Sometimes it doesn't work so well. It kind of skips around the mesh, so if it does that, just hit ctrl + z. And I'm going to ctrl + click around that side. Ctrl + click up his hip on this side, and we're going to guess right about there is where our seam was, I think it was one back. Whoops. Again. That's not Blender, that's my clumsy fingers on the keyboard there, doing that. We'll click that. Ctrl + click up above. Shift + click there. And like I said, if it skips around, Blender's doing what it thinks you want it to do, it's just taking the long way around when it does that. So the way you can get around that is just hit shift, and then ctrl, and it's going to go zipping right up there, so it's kind of like you're drawing on the surface. I'm hitting ctrl again. See if it, now it should go from here, all the way up here, let's see if it makes that run. Yep. Pretty good. And it looks like we probably went up... We'll just add that there. We'll hit ctrl over here. Okay, so see that's kind of like a big piece of fabric, think of it as drawing on his shirt, there. What we're going to do is cut along there. So we're going to now set the seam. We do that by coming down to mesh, edges, or ctrl + e, I'll probably be hitting ctrl + e from this point forward, and we want mark seam, which is just off my screen here, but it's right there. Mark seam. It's going to turn those seams dark orange, also open edges it sees as a seam, you don't need to mark anything that's an open edge, so I've got that big neck piece, that's an open edge. All right, well great. But nothing happened over here. So, we need to unwrap it. We've got to tell Blender we want to unwrap it. First you've got to tell Blender what you want to unwrap, we don't want to be clicking all these polygons in here, so just hit a. Well, there's your unwrap, you can see it's a great big mess right now. That's what the unwrap looks like naturally. But we're going to go to mesh, unwrap, or u, and then unwrap. It kind of says it twice, but that's all right. And what we're going to do is let it kick in, and there is our unwrap, now you might be wondering what this big chunk of stuff is. Let's zoom in here and take a look. That's the rest of his body, and I'm assuming these little spiral shapes are his arms, these are probably his legs, and he's just a big old mess. Looks like roadkill there. This piece over here, though, that is his chest piece that we just did, now it looks a little different, this is probably that area right there, I think is right there. These areas over here, here and here are those areas right there and there. That's the underside of his arm, right there, and that's that seam along the side. Now you might be wondering how I figured all that out, well, it's because I know there's only two parts, the part we did and the rest, well, that's the rest and that's the part we did, and you kind of get used to looking at these after a while. You can see there's his chest. So now that we've got this piece, let's look at a couple other ways to deal with that. That's probably too big of a piece to really work with. It would be hard to go into Photoshop and figure out what we were looking at, there. So we can cut it up. So if we go again to edges, make sure you're on edges, I'm going to select here, again, ctrl + clicking all the way through, and kind of following that line to the other side. Now we're going to go to mesh, or ctrl + e, and mark seam, and there's that bright orange seam. By the way, don't worry when they turn red, that just means that they've been unwrapped. A dark orange seam means it's there, but it hasn't been unwrapped yet. It's not really that important. And now we'll select everything. And you'd say, "Well, where is it? It didn't do anything." So, what we want to do is come down here to mesh, unwrap, unwrap again, and now we should have, when it's done, three parts. Well, there they are. The rest, and our two chest pieces. Now, it doesn't order these in any particular order, it just puts them into that space, or on that grid, in a random order. For now, that's fine. Just leave them in whatever random order they want, you don't need to scale them or do anything to them, we're going to do all that later. One thing that might help you while you're at it, is, by default, this tab is usually on tools. These are your UV editing tool sets. If we go down to, under options, that tab right there, click live unwrap, and what that's going to do, and we'll see it here as I unwrap one of these arms, it's going to show us what's going on live. Now, it may look a little confusing for some people, some people like it, you can decide, you can either turn it on and off, but let's see what that looks like. So, I'm going to go over here to his arm, and we're going to deal with this kind of cylindrical shape of his arm, because there's one trick we have to deal with with cylinders. By the way, when we turn this on and off, the a key, which is selecting everything and deselecting it, everything disappears over here. If you don't like that, then you can click this button right here, it's usually covered up, you kind of have to shove your window over a little bit. It's this button right here, which has the memorable name of keep UV and edit mode mesh selection in sync. Most people call it sync mode, you can just click that, and now, when we click on and off, we'll be able to see it. Probably helpful for now, we'll get back to that button later. All right. Back to edges. Click right there, I want that on there. I'm going to go around his arm and I'm going to just let this kind of wander over to about there, and then we'll cut this right under here. No need to keep going over any edges you've already got. Now, I'm going to give him kind of a band over here, and cut his bicep/tricep area here off from each other. I don't need to keep clicking, I can just use alt for that. And what it should do is, click it, and you see how it deselected that one that I just had? I'm going to hit ctrl + z. If I hit shift + alt, it's going to keep both of those in place. All the buttons in Blender, the shifts and ctrl + clicking, and the shift + alts and shift + ctrl, that's all confusing for me as well. If you don't like keeping track of that, or you find you keep just losing the seam that you just built, you can always make one seam and then just ctrl + e, and mark seam, and you can do that after every seam, you don't have to be marking a lot of seams at once. Now, see how it automatically shot over here and did that? We didn't have to hit unwrap, remember, we were coming over here to unwrap, and unwrap, and... That's what the live unwrap button does. Now, I like that, some people don't like it, because they're not used to working seeing things unwrap, like right now, that's actually unwrapped incorrectly, because I have not put a seam on the bottom, but that's what I wanted to talk about. All right, this is the bottom of his arm, right here. And that is the top of his arm, right there. They're both wrong, and that's because we don't have a seam running all the way across, like a zipper, to unzip that, so think of this as a toilet paper roll, and just because I mark the two ends of the toilet paper roll, there's no way to unwrap it, or make it flat, you have to cut some part of it, and you can see, there's the seam there, there's the seam there, and if I mark that seam, ctrl + e, mark seam, everything's going to flatten out here in a second, and now I have lots of flat pieces. If they look a little strange, well, that's just what they are. We're just not used to seeing them flat. That should give us enough tools to at least move through the big parts of the body, so at this point, what you're going to want to do is mark the seams, or try to mark the seams, on the body of your creature so that you have some great big kind of chunks of pieces. Try to keep them so they can be flat, so maybe like a back and a front, or a top and a bottom. Don't get too fancy. Don't try to unwrap the whole thing, say, in one piece. Little pieces are just fine. Also, don't move the pieces around over here, yet. We'll let Blender do that by itself here in a little bit. I'm going to continue on down the road here, and I'll meet up with you once we get to another piece of the body, like the head or the hand.