#UE5 Series: UV Mapping Tools in UNREAL Engine

hello everyone Reza here welcome to another Unreal Engine 5 video in this tutorial we are going to pick up where we left off in the previous one and we're going to talk about UV unwrapping in Unreal Engine 5. when a material uses textures for its channels like base color or normal map or roughness so on and so forth It's typically he's going to use models UV mapping to specify what part of those textures will get unwrapped around what part of the geometry and that process is called UV on wrapping so in this video we are going to focus on the right tools to get this task done within the application let's get started [Music] thank you here I am inside Maya now I am going to bring Billy the character that we use for our facial rigging for beginner series into Unreal Engine 5 and I'm going to do that twice once with UVS just to see how we can visualize our UV information inside Unreal Engine 5 and the second time without any UVS to see how we can UV unwrap a character or in 3D object if there is no UVS now a bit of a disclaimer here still until this version for best result I encourage all of you to UV map your objects in a dedicated modeling tool such as Maya blender so on and so forth but it's not always possible for example when you import data from CAD modeling applications into unreal you may not have high quality UV Maps so for those type of scenarios you probably can use the software still very useful to understand the tools that we have inside unreal so we can use it when the time is right so right now I've got this UV Islands available for the face for the eyes and for the hair and I'm good to go I also prepared a UV Checker so if I double click and bring over my UV Checker I made this UV Checker in UV Checker maker and it's an 8K texture I'll make this available to you along with this little guy in my patreon page so you guys can follow along but for now let's select everything and go to either send to Unreal or export selection I'm going to export it as fbx and Export selection again we talked about this process in the past smoothing groups on scroll all the way down make sure access conversion up Axis is set to Z and you export billing alright let's switch back to Unreal Engine 5 my scene is ready online need to do is just to bring those models and the texture in and we're good to go here I am inside Unreal Engine 5 I've got three rectangle lights and one simple Skylight ready to go uh so all I need to do just to bring the Billy with and without UVS so I've got Billy with no UVS and Billy with UVS I'm going to select those bring those in no need to convert any scenes so I'm going to select that and bring that into position I'm going to press f on it and we can see that we have Billy right here I believe this rectangular right has got a bit of a too much of pink in it so I'm just going to kill that I want to get somehow a sort of a neutral color information I'm going to press F and maybe just maybe bring this to something like 40 bring my field of view that's much better it's got Lambert on it you can see Lambert I don't need Lambert so I can just delete that so let's bring our texture UV Checker I'm going to bring the UV Checker in double click on it make sure srgb is on because we are going to use it for base color now I'm going to double click on my material and in here assign that to my material so UV checker comes up here there I have my UV Checker my roughness should be set to one I don't want Billy to be super reflective apply save again we talked about all of these steps in previous videos that's why I'm not spending too much time on it I'm going to right click force of habit Make an instance out of my master material material instance and I'm going to drag that into Billy so we are going to see the right checkerboard in there because we already have UV Islands on this guy and it's only expected to see correct UV information all right now we're good to go the only thing I need to do is to load the Plugin or make sure that the plugin is loaded so we have access to the right tools last step of our preparation I'm going to go to plugin I need two plugins for this one is UV editor make sure that it's on once it's on then you restart the engine if you already have this on then you have nothing to worry about may have noticed that at least for this version It's set to experimental so we should expect to see some glitches also if I type in mod link make sure that you have modeling tools editor also enabled because UV editing tool is part of this modeling editor tool set so you have to have both of these plugins turned on [Music] all right I'm in the modeling mode so shift 5 switches from your select mode into modeling mode and we're good to go first things first I'm going to visualize my UVS in the static mesh editor so if I click on my model and press Ctrl E I switch to static mesh editor so the good thing about that is you can actually see the model first adjust level of details adjust materials if you want to but you also can access its UVS and surprisingly we have two UV channels so if I click on this one this is actually what I made in Maya and that's all good it shows it correctly but there is another Channel and that channel is just doesn't make any sense I'm not really familiar with this now sometimes you run into this issue it's really not an issue basically what you see in the second channel is not the UV information for your textures it's actually your UV information for your lights so what I see in this UV channel is the information that's been stored for my light Maps now if case if you don't know what a light map is is a special kind of texture that stores pre-comp lighting information for all the missions that you have in the scene so if your light if I just come here and select the light if your light is set to static or stationary then I have no choice but to go in here and build lights and as soon as you build light on real engine uses this information through the light Mass tool to save all the indirect lighting information into light map textures so basically what I'm trying to say is don't touch that what we use is Channel Zero and remember that channel all right so that's how we see our uh UV information in Unreal Engine there's another way of seeing actually the information in Unreal Engine and that is through modeling uh tool set and going into UVs layout if I click on layout you can see that my UV information is actually displaying right next to the character now the funny thing is this is not what I made the UV islands are the same but the order and position of them have changed as soon as I clicked on layout simply because layout by default is going to reposition and re-arrange my UV Islands if you want to see the original one the one that I actually made you go to UV layout layout type and set that to transform that is what I made in Maya now you may say well what's the point of the other two repack is going to keep your uvi lens or UV shells is just going to reposition it for better Real Estate so you get a much better use of space sometimes and the other one is stack which unreal tries it's best to stack all the UV Islands on top of each other as much as it can well you do see an okay checkerboard in here but you have overlapping UV shells so for a character that may not be a big of a deal but if you're modeling a prop and you've got let's say wood fibers all of those fibers are going to overlap and your texture is going to look really really weird so you have to be careful again if your purpose of doing this is just to visualize what's going on then set it to transform and you can of course change the scale if you want so it scales up the display and gives you a finer checkerboard you can actually use a checkerboard here through preview material use a checkerboard use the original that I assigned to this very material or you can go ahead and override it with the material that you pick so it can be just a default material that you have in mind as a matter of fact they always have a UV checkerboard in my content drawer so I use that as an override sometimes I just want to toggle between my original texture and my checkerboard in that case override would be a good example for now the whole idea is to focus on the UVS so my original material is actually my UV checkerboard and of course you can turn it on and off if they feel like this window is not needed you just want to see the checkerboard or you can actually reposition it but bring it from the right hand side to the left hand side or even scale it here it's not going to scale the UV Checkers it's just going to scale this window right here or even reposition it so I can actually move it up and here in case if you need to you can of course turn off the wireframe with that you can actually see what's going on here and it makes it slightly easier to have a look at things once you're happy with your model and you feel like you know you've already repacked it the way that you want you go ahead and click accept in my case not interested I'm just going to cancel so that's how you visualize your UVS inside static mesh editor and of course with the help of layout button inside the modeling editor let's go to the next chapter and see how we can UV unwrap a model from scratch so what I'm going to do is I'm going to replace this guy with Billy with no UVS so we see how we deal with no UV is in case if the situation calls for it by the way before we move on to the next chapter you may ask how to delete UVS you can just easily select Vox wrap so select your model apply Vox wrap to it it actually turns your model into voxels and now you can see this model does not have UV so if I go to layout you can see the UVS are gone but I personally would never do that because you just change the topology of your mesh so if I go to lit and go to wireframe you can see all of a sudden we have a very dense model and that was not the case because Unreal Engine actually turned your model into a bunch of voxels and that is the original topology that I had in mind and I really don't want to touch it so I'm going to bring Billy with no UVS in the next chapter and see how we can benefit from these tools to very quickly UV unwrap a static mesh so I've gone ahead and replaced the old Billy with the new one and the new one does not have any UVS so if I go to layout you can see there is nothing in there where should we start select the model and well first things first I need to make sure that the material that I created is applied so the material is there but again we're not going to see any information in there uh the easiest tool and the the first one to try is actually Auto UV that auto UV is actually going to unpack and rearrange your UV shells automatically you have no control over where the seams are and how this UV coordinates are going to be created but well it's fast and it's easy so let's go to UV and voila all of a sudden we get a checkerboard on our model now first things first UV channels set to UV zero that's what we want we have three types of UV creation a patch Builder UV Atlas and X Atlas 33 different methods of UV mapping I am not going to get into the technicality of what UV is going to use what algorithm and how it's going to change it best is to try and see which one gives you the best result I'm also going to change the material into original so I kind of see better what's going on you can see it's not that pleasing I can bring in the UV layout to have a sort of a clear version of what's going on here you can see we've got too many islands seams are everywhere and it's um not the best scenario so best thing to do is to play around and see what attributes you can change to improve on the situation I basically noticed that patch Builder is not my favorite if I have to use Auto UV the one that I found the closest to my taste is actually X Atlas and again the algorithm is different for example if I bring this one here that's an article from Microsoft talks about how UV Atlas works I put the link in the description below just go through it if you're very interested to see how each method Works UV Atlas is there it takes probably the longest as you can see it's now calculating and it gives me a sort of a different result but X Atlas is actually very quick and it gives me a good result still seams are not ideal and again you may may not want to use this since it's pretty quick I personally not a huge fan of Auto UV [Music] the good thing about unwrap is you can actually Define your own islands and that gives you more freedom so if I readjust the model and go unwrap you can see right off the bat it gives you more attributes now the one that I really like is actually not existing UVS because I did not have existing duties but polygroups so you can actually prepare the model and say you know what I'm going to use polygroup and by now hopefully you know different ways of creating polygroups so one way is through try select where you can actually select the model and create polygroups let's say I'm just going to draw and say you know what that is one area that I want to have as a UV Island and uh holding down shift to delete the areas that I don't want and I'm gonna say I want this to be a polygroup so you go and use that as a polygroup and then you can say you know what I want the ears to be a separate polygroup so I'm going to go in here and select the ear and again I can zoom in and spend all the time in the world to be as clean as possible now let's say I've got the ears selected I'm just going to go through it really fast but of course when the time comes you kind of need to take more time and be accurate but let's say that is going to be a polygroup and then I'm going to select the nose with nostrils and everything and I'm going to make that a polygroup foreign with that I'm gonna go and click on unwrap now it's still a bit stretch obviously because I did not um put any seams on the face it's just a nose and neck and two ears but if I go to layout you can see it actually listened to what I suggested so I have two ears and if I zoom in you can see I've got B9 here and if I go in here you can see B9 is there so I've got the ears I've got the neck ready to go and I've got the face which is still pretty terrible but you can actually work on it and give the front face a polygroup and the scalp back of the head a separate poly group and really bring it together so the fact that you can actually test and try your own Islands uvi lens will give you a great result now just one quick thing about this window since it gives you way more options to work with for the unwrap type I tend to use conformal because it's a little bit expensive but it reduces the stretching whereas x-map is very fast but sometimes it fails to deliver the required result but still anything you choose it still goes through the UV islands that you picked through this UV unwrap tool which gives me the the most amount of flexibility if I may to spend the time convert certain points or certain faces into certain poly groups and with that you can get the job done in hard surface modeling I found this very very useful especially you don't need to deal with hundreds and hundreds of polygon on an organic model with hard surface let's say if it's a plank of wood all you need to do is just to select the top face and surrounding faces make them a polygroup back face a polygroup job done now let's go to the next one project now the next three tools may work together so the first one project is something that may sound familiar to majority of you if you have worked with application packages like Maya we have projections UV projections in Maya and that pretty much does the same thing so it creates a type of a projection plane if I click on this we've got the targeted UVS and then we have a plane which in from that plane you get a snapshot and that creates the UV shells now you may say wow that is pretty neat very clean there's actually nothing wrong with that and that is true but as soon as I start rotating you can see I'm getting stretching happening on the sides because it's only projecting from the front and it goes all the way to back but sides usually look terrible now you have in here cylindrical projection which is good and also box which is not too bad I found that sometimes box actually works really well especially with prop modeling not much with character modeling but um usually with projection because we don't have enough complementary tools such as unfold this will fall short and may not give us the result that we want we've got autofit as well that can sort of fits it so if you only look at an object from the front view then this will give you the exact silhouette with somehow a little bit of inaccurate aspect ratio but gets the job done so you can see that these squares are not really squares they're still stretched a little bit simply because I set the projection to autofit so you can go out to fit a line reset it can go even here and I can rotate that like so and you can somehow scale it to bring this slightly closer to an ideal evenly distributed checkerboard so now the aspect ratio is good so you can see it's not really automated you have to scale it properly rotate it and realign it but all in all this tool is available in case if your object is not going to be seen from the sides and if that's the case this tool is for you you can use it and get results next one is edit seems so if I go ahead and unwrap using polygroups you can see we have a seam here and we have a seam around the ears as a matter of fact I can turn off the visibility of the hair we can see we have seams around the ears we can actually edit an add seam so as soon as you go Sim edit you can actually see the seams now I can go in here and add a seam like that and I can go and carve out this cut at the back of character's head so when that opens you get a slightly better result last tool is xform UV and that is responsible for transforming UV information in your UV space so if I go to layout X form UVS it looks at each island and it says if you wish to move or reposition your UV Island you sure can for example with the nose I can see M12 I can actually select that and reposition that so I'm going to go into I'm 12 and if I can move that to let's say a12 now you may say reservoids that important sometimes you actually want to line up patterns you have patterns which you would like to line up so if I go in here into layout um all of a sudden you can see my UV Island for the nose actually moved I can do that again so you can see the position of this little guy will change if I go in here and select this UV Island and this time I bring it further if I go to layout you can see it's moving down and basically we're losing control of this so double it sort sometimes it's good if you have a sort of a repetitive pattern it's a really good idea to use this tool to line things up but at the same time you're going to be you need to be very careful not to overdo because then you may run into some problems for example now I moved it up and it's overlapping if I go to show wireframe you can see now the nose uvi land is overlapping with the back of the face UV shell so these are the things that you can run into again we talked about this this tool is still work in progress but I still want you to know about this tool and its capabilities so in case if you need it you can just bring these tools to use all right that should do the trick for this tutorial thank you very much as always for all of your love and support stay safe and see you in the next video

Channel: SARKAMARI

Views: 15,499

Keywords: unreal engine modeling tutorial, unreal engine uv mapping, unreal engine uv unwrap, unreal engine uv editor, unreal engine uv tiling, unreal engine uv coordinates, unreal engine uv channels, unreal engine 5 uv mapping, unreal engine lightmap uv, unreal engine uv

Id: eQc2Yz8hyeQ

Length: 27min 46sec (1666 seconds)

Published: Fri Jan 06 2023