Advance Unwrapping & Making Texture Atlases | Blender 2.81

hello and welcome to GABA Media I'm grant Abbott and today I'm going to talk about more complex UV unwrapping so for this example and tutorial I'll be talking through how I unwrap an entire set of game models onto one UV map sometimes known as a texture Atlas and I'm using the example of the game atlas empires which I'm working on at the moment I'll try and keep it as simple as possible but it's not really a beginner's tutorial but if you know a bit about unwrapping then this can help you with the next steps of unwrapping game models I will explain unwrapping as well for people that use picture based textures or PBR textures but this is mainly for painted textures ok so here is my set of models and there's ten models altogether and it's four stone quarry and the way I've modelled it is that I've got lots of separate objects in fact if I select them all and go into edit mode you can see the makeup of the objects they're fairly basic and simple there's a bit more complexity in the stones but that's actually just because they've been triangulated I've borrowed these from other sets so they've already been unwrapped so I'll talk a bit about the baking process in a second you can also see that I've mirrored some objects so there's a mirror here whenever you unwrap a mirrored object that means it will share the UVs with the other side if I go into this cog in here you can see that I've mirrored this twice so in the X and y-axis all these other three sides will share the same UVs as this side here now it's quite important that I can only do it this way around because the top bit has to be lighter than the dark bit ideally the back bit would be darker than the front as well because it's in this crevice but I'm not going to worry as it's not going to be seen particularly well from outside here you can see that this model here has been mirrored in the y-axis so again I can give it a lighter top to the bottom and I can make the back of this darker but I couldn't do the same here because the tops going to be lighter than the bottom so I couldn't mirror across the z-axis in this case the problem you get when you mirror is that some of the details can look very symmetrical so you can't add as much character so I try and keep away from it if I can but sometimes I have to do it because of the texture spaces needing to be kept small you can also see that the cue and the rope sort of barrier have already been unwrapped and have already got textures on like I say they're borrowed from another set but you can see the way I've unwrapped them here so I've cut them in half so you'll get two islands one there and one around the bottom now you think I'd want to delete the bottom phases but I don't actually want to do that yet because there are some bottom faces in here and these are all the same object so it's a linked duplicate and that's quite important when you're doing a big set like this I only want to paint one of these and then they will repeat across here because they share the same UVs so to do a link duplicate instead of pressing shift D you press alter D and that creates your duplicate but it's a link to duplicate so whenever I adapt the shape and click on a vertex there it will move all of them and that's a great thing with linked duplicates they also share UV space therefore the UV unwrap will be the same across all of them but I will have to go in at the end unlink them all and then delete these faces that won't be used but that's once they've all been textured and baked in this case then I'll unlink them but they will still share the same texture space but I'll be able to edit the models individually so I'll be able to delete faces and move edges around if I wanted to but that would distort the UV map as well so let's unwrap a couple of things and show you the process so let's start with something simple like this beam here so I'll come out of edit mode just select that object and you can see it's mirrored across to the other side so I only have to paint one half and I'll go into edit mode for that and I'll isolate it so it's quite simple the ends have been cut off because they're inserted into the ground in this case and into a log in this case I'll just come out of isolation mode so it's inserted into that log and I want to cut this up the best place to go obviously is to the UV editing workspace I'll have to isolate again though so I can see what the UVs are going to look like I'll choose an inside edge not that it matters a great deal where the seams are because when you're painting you can't really see the seams but it would matter if I was using pre-made textures or pictures for my models so if I go to edge mode and alt left click on one edge I've got my edge selected I can press ctrl e and Mark seams now if I select all you can see there's a really unwrapped already because this was made from a cube but as soon as I press you to unwrap and unwrap again it comes out okay now if you get a warning message down here saying it's got non-uniform scale then you know you haven't set the scale and you would need to go into object mode control a and set the scale so that's a nice simple one for the moment and obviously this unwrap won't work at the moment because it's using half my UV space but I've got to put all my other objects in here as well but for now I leave it as it is so I'll come out of isolation mode and unwrap something else so these pipes for example let's zoom in on those into edit mode and you can see it's a link tube to get with that one and obviously all the other sets across there so into isolation mode and again this sort of inside face here is probably going to be the best but because it's a link to placate I may have rotated this so it wouldn't end up being the inside face for other ones so this one for example it's still roughly on the inside but there's a few more around the place where I've duplicated this but anyway back into isolation mode so I've got that edge selected and I'll press ctrl-a e mark seams and then I'll select all and it's got a cylinder unwrapped at the moment but if I unwrap again it's a bit of a mess at the end here now have a think why do you think that is it's because I've got this circle at the top here and it's trying to unwrap it without any seams on it so it's sort of spreading it out and the analogy I use is kind of like a crushed coke can it sort of squishes it down and squishes it on top of each other but if I come in here go to face mode and select that face and you can see the position that faces in up there so when I select all that's why it's all squashed at the top so back to that face control e mark seams and then unwrap again and now we can see it's separated those two objects and we've got a much cleaner unwrap here with less stretching and stretching is where it was trying to bend itself around the top face there there's no face on the bottom so it wasn't causing a problem and you can see these are fairly rectangular or fairly uniform shapes which is exactly what I want you could argue that I could add another scene down here because there might be a tiny bit of stretching in here as you can see a sort of stretches out at the end I don't worry too much about that I don't want too many islands to have to deal with in the end again I could have another cut around here as well but like I said I don't want too many islands ok back out of isolation mode we'll do one more there's slightly more complicated one perhaps there's not that many complicated shapes though I'll show you what happens when I unwrap one of my mirrored objects so I'll select that into edit mode into isolation mode and you can see if I select my faces it's cut in half like this we'll see what that looks like when I unwrap and it's not too bad to be honest it will be a bit of stretching around the edge here but in general that's pretty much ok let's come back out and think about the size of this object how it's going to be seen and whether I need a more detail unwrapped it's a fairly prominent object which is why I didn't mirror each corner and only married across because I want to paint the bottom darker than the top but as unwraps go that's not too bad there'll be a tiny bit of stretching around the edges here but that won't be a problem and of course we're only seeing one side because it's a mirrored object so it will share the UV space you paint on one side it will appear on the other I'll go for this one now so back into edit mode and this one has been mirrored twice so this way and this way and I think it'd be a good idea to actually cut this in half so I've got two UV Islands so I've cut right in the middle control a mark seems select it all and unwrap and now we've got two quarters like that so I've got to go around my model now and unwrap each different bit so I'll speed some of this footage up so it's a bit quicker for you for this object I've taken the end face and I've unwrapped that as well much like I would with a cylinder so this will wrap around like a cylinder and then the end face will be separate and it's a nice clean simple unwrap which will look like this these bits have sped up five times but I'll put commentary over the top where I think there's some useful bits so this rock is slightly more complicated and I've gone round and just cut it into quarters this bit will be a bit bigger and not stretch across here but hopefully that should unwrap correctly if I unwrap that it's not too bad although this bits a bit too stretched if you need to see where your UVs are you press the link button up here and now I can select these UVs and see where they are so I probably need to unwrap this box separately B as you can see it's stretched quite a lot there and also it's got a face on the bottom that's a problem as well so I'll delete that face that might give me a better unwrap and that's a lot better actually so just cutting things into sort of cubes and rectangles so they'll fit into neat Islands similar to this now you might think with an object like this it's already got an unwrapped so I don't need to unwrap it again but I find it's a bit glitchy if it's got its original unwrap and when you go to do your sort of texture atlas with all your maps on top of each other and then pack them all into this space if it uses the original unwrap it can be a bit glitchy and just make itself really big and sit over the top of every other one when it's unpacked so I will actually unwrap it once again so I never use the automatic unwrap for these things I'm just going through each one methodically one by one in order and I'm not trying to put them all into a texture Atlas just yet you do that all at the end you can see for this area here I actually had some extra polygons which I thought I'd get rid of before the unwrap occasionally for an object like this you might want to change the unwrap method from angle based to conformal as you get a better unwrap and it's less stretching so in this case I've accidentally put some scene here and it's ended up with this horrendous map here I can just go in control eat and clear seams if I need to clear them and then you have to re unwrap and it's fine now you so last quick check to see if I were up there it looks like I have I'm looking for everything that's selected because obviously the other halves are just mirrors I'm making sure they've got orangey colored lines on them so I'm going to the next model now and seeing what's different and what hasn't got an orangey line and in this case the only difference is this new sort of pipe here and you can see all these maps sitting on top of each other I'll be able to pack those later on into position now you can see this one's quite stretch when I unwrapped it and it comes across at an angle like this again to try and just select this edge here control ET mark seam and see what difference that makes and you can see it's kind of like a cardboard box that needs a seam in there just so it can unwrap without so much stretching so a slightly better unwrap when you think of it like a cardboard box like that you can see here that I'm using the Silla that are down here up here as well for this support beam I won't be able to put any shading around here that's the only problem with this technique so because it's sharing the UVs you can't add that detail like shading it's quite distorted this one so I think I'll cut around here as well does create more islands but it's a slightly better unwrap with less stretchy occasionally in the unwrap process I'm going through finding a few errors here and there and deleting a few faces if needed and that's just the general sort of tidy up it's helpful to go over your models again so just there filling in that area where there was a stone out of shape now this was an interesting one because it's left me with a very strange unwrap so something's gone wrong somewhere I need to isolate and go and see where I'm missing a scene and you can see that there's an extra face there so it's joined this whole island here around the corner to this one as well and I just don't need that face there and that's a lot cleaner so I'm checking to see if there's anything different on this one you can see that this one hasn't got any orangey ready lines so I haven't unwrapped that yet it can be a pain if you miss something and you haven't unwrapped it and you didn't realize what I tend to do is select everything at the end and unwrap once again just to make sure that I've got everything and I've unwrapped everything the only problem with that is you can't separate conformal and angle based for different objects so you have to go in and look at your UV islands and check which ones are a bit out I'm asking to delete these ones and then just duplicate this one when I finish texturing so I can see where these different poles are when I've added in the shading for them and then just duplicate them around to here but I'll do that once I've actually textured but for now I'll delete those so that they don't cause a confusion when I'm unwrapping you there I've got that error message which says uniform scale so I will need to go into object mode control a set the scale and that means my item has now got scale 1 if I undo that quickly you can see that it's got non-uniform scale there and that's what you're looking out for and it won't unwrap properly if you have that so now everything should be unwrapped if I select all and go to edit mode and select all again there's all my unwraps on top of each other you can at this point to go up to UVs and pack Islands and then you've got a pack island option there and you can turn the margin up if you need to I like to turn mine up to point zero zero six because it's nice to have that space when your texture painting when your texture painting you don't want to see the seams you've got to be a bit careful now I'm noticing a few errors if i zoom into this window so ctrl spacebar to isolate there's an error here with this shape and I'll just check for any other errors so I'm looking for fairly uniform simple shapes but you can see there is definitely an issue here where there's some sort of distortion so with that button selected as I've got there which will link it to my selection I'll go back to previous with ctrl spacebar and try and find where that is by pressing full stop of a numpad and coming into the area that's a problem and it is actually the bit that I said I was going to get rid of but I forgot to get rid of it in these two shapes here so into object mode delete that and delete that one so I'm going to copy this one across later on so let's select all into edit mode select all again and then pack islands again and there we go that's nice and clean and no issues however what I'm going to need to do because I may have missed something and not unwrapped it I'm actually going to reown wrap everything so select all unwrap and unwrap once again now you can see there's a object has non-uniform scale because there's some objects in here that I've rescaled I'll give you an example so this object here that's got a scale of 1 but I've used that for these poles in here which is quite a pain because I need to go through and hide everything that ivory scaled so it doesn't cause issues with my unwrap so I'll come in here select these and hide them so select all again into edit mode select all unwrapped so they were the only things that were rescaled so I've got a nice clean unwrap again let's have another closer look the other thing I'm going to do is go to UV unwrap and average Island scale now that should give me an unwrap that considers the scale of these objects in relation to each other so it will unwrap big objects with big space and little objects with a little space it didn't move much because generally speaking blender does a good job with that automatically but if you're worried about that then doing your average island scale will help you you'll need to pack Islands again to get your margin in there once again so unfortunately I've made an error and I forgot that these objects here that previously were textured in the correct way because they're UV maps which are down here UV maps were set up for the old texture and I've just really wrapped them so they're all over the place now so what I'll have to do is append those items back in and then link the UV maps up and then re unwrap everything again with an extra UV map but I'll talk about that in another video I think let me know if you're interested in hearing about the baking process and appending objects in from other files and I'll happily go through that next time the other thing I was going to mention is how you would map certain textures to these different objects so I've got an example here of different textures being on one map so you might have let's say roof tile texture here or some stone textures as well and with your unwrap of each object you'd go in and you would move it into position and map which texture area you want it to be on and you do this for each object you'd go in and you'd map for UV maps grabbing the islands is the easiest way so let's turn off our sink and grab the islands and you'll be able to move those into the different positions as you felt fit you can't see it changing on here because I haven't actually put this texture on a shader yet so I just quickly put that on and now when I move these you can see them moving in different ways so that's where it's more important to have a clean unwrap and not show your seams because obviously the seams are going to be very visible so you try and show as few seams as possible see if probably have bigger islands so this one for example would be one big island but because I'm texture painting I can have slightly smaller islands so I can pack my objects in a bit better the other thing to note is you can overlap these at that point overlapping UVs isn't the problem so I could put all these on exactly the same space and have one really weird wooden stone there but obviously you can't do that for texture painting because soon as you paint on one texture it will appear all over the place so that's my unwrapping process that UV map will be now ready for painting and you can see the painting process in the stone quarry time-lapse with commentary so thanks for watching and I hope this helps you out and I'll see you next time

Channel: Grant Abbitt

Views: 50,018

Keywords: understand, texture, paint, learn, blender, tutorials, 3d, art, graphics, game, material, guide, easy, sculpting, painting, blender (software), blender 3d, blender paint, blender painting, blender texture paint, blender texture painting, blender tutorial, cartoon, gabbitt, hand painted textures, media, painted, style, texture atlas, unwrap, blender 2.8, blender 2.8 learn blender, 3d modeling, how to make video games, make games, unity

Id: gZRDwbHEB34

Length: 19min 54sec (1194 seconds)

Published: Thu Dec 05 2019