How To Add Root Bone to Mixamo Characters Using the Skeletal Editor on Unreal Engine 5.4

[Music] hi everyone Paulo here welcome back to the channel where I make how do videos time for another Unreal Engine tutorial in this video we're going to learn how to add a root bone to mixim Mo characters using this scal editor on UE 5.4 so you could go ahead to mixim mod.com sign up it's free and then you could download some characters in here but the only problem with this uh characters if you want to use them in Unreal Engine is they don't have a root bone so we're going to add the root bone to these characters using the scal editor feature on UE 5.4 which is now in beta and then we're also going to cover automatic retargeting and also fix some common issues after retargeting let's go so I have the uee 5.4 project open here so I'm just going to go to the content drawer create a new folder for miimo and I'm going to import the model that I just downloaded so I have this scon which is on a particular to post I'm going to import that cool and I'm going to create another folder called animations and I'm going to import the animation that I downloaded which is a hip hop T so I'm going to select the miximum character for the skeleton and import cool so going back one folder High I'm going to open the skeletal mesh here uh as you can see this one only has a hips so we want to add a root bone to it now to enable the plugin just go to under edit and then plugins and search for skeletal mesh editing tools enable that say yes to the prompt and then restart the engine let me save everything cool so once that is enabled if I open the skeletal mesh again I should have this uh New View here so the editor is different so I can click on the edit edit bones icon here and click on edit skeleton and then I could add a skeleton to this character so what I want to do is uh create a new skeleton that would be on the root location here and then this hips would stay on the same a right so to add a root bone you can't just click uh you can't just uh create a new bone like so and try to reparent this hips to the to that new bone it just doesn't work so what works for me is I'll remove this is I'll duplicate the main hips bone so I'm going to click on duplicate and it would create a new bone for me called hips one which be which would be on the same location that it currently is and then I'm going to rename the hips to root and I'm going to reset the location and transform of that bone to move it down and then the original hips that uh was duplicated I'm going to uh reparent that to the root and for the spine reparent back to the hips same with the left leg and the right leg and I could rename this to back to hips cool so now I have a root bone and I have the hips the problem with this setup though is if I go under this edit skin weights and I click on edit weights if I click on the root you would see that there is some weight Associated to that root bone but nothing on the hips so what you need to do here is weight paint the hips with the same uh details that you have for the root so this could get a little bit tricky and I think weight painting is one of the hardest thing to do uh when you're U modeling um so what I normally do is I'll go to the hips and and hit the B shortcut so that I could reduce the radius if I drag it to the left it would uh decrease the radius if I uh drag it down it would decrease the strength so I'm going to reduce the strength around uh this size 55 and I'm going to start painting so I'm going to select the hips I'm going to start painting like so and do this a couple of times so if I switch to the root here you would see that it's starting to get um lighter as well so let me increase the strength of my brush here so it should be around 50 half all right and I'm going to paint it again and if I look at the root starting to get there so I I would do this for uh couple of passes until it main root bone here kind of disappears so this is a lot of precision I would say to make sure that the weight painting works so I'll Focus just on this area on the main area cool and then you need to do the same thing on the back so several passes like so and still more Yep that is looking better and then I'll make some quick passes on the top and bottom and I'm going to rotate check out the hips and make one pass on top one pass at the bottom here maybe a few more here at the bottom cool now what I would do is remove the other weight paints on the root here now that I have the main hips painted so to do that hold the control key and you could remove the weight paint on the part of the mesh cool so do that on the front and also do that at the back hold the control key and just paint to remove those um weight paint so this is not perfect and there's a little bit more there oops I don't need to add that cool and I think there's a little bit more there right once you're finished go ahead hit accept and now if I quickly save all and you can just jump on the animation tab here and preview one of the the animation that we did so you would see that there are some slight mesh deformity on some areas like I could see it from here that's because of the way I removed some of the areas so you could go back here and click on edit weights again and then continue weight painting this until uh the meshes are kind of um lining up perfectly so that's one process to do it but now it has a root bone and the and and we managed to weight paint it so for now let's give it like that and let's go ahead and retarget this so if I go to the ue5 mannequin and open the animations and look for ab Manu I could right click on that and use this new feature the retarget animations feature which I covered in my previous video and then I'll select that character and I select the AP Manny blueprint and all of this um animations here oops except except this I'll click on export animation and I can select the uh folder I want to save it through so I'm going to save it there and click on export cool and if I go back to my folder under animations I should now see this animation blueprint so I could go ahead and first rename this so ABP uh eraser if I open that uh there's some deformities H happening here so if I open the anim graph the control rig foot ik is not yet properly fixed so we'll fix that in this video so for for now I'm just going to detach it so it's not link compile save so after compiling I get this warning at the bottom here saying my fall Loop uh has a warning so I'm just going to open that sequence and uncheck the Loop animation here compile that should remove that warning cool let me save again now we could go to the third person template here go under Blueprints and let's swap out the mesh so click under viewport mesh swap out the character skeleton with the racer and select the uh Razer blueprint that was created for us so when to compile save and hit play here on the level uh there's something wrong with the foot we'll fix that and when it runs it looks fine when it goes on the ramp there's no foot ik so we'll fix that as well and also when the character jumps there's this weird Landing animation that it's doing when I escape that it's it's going to tell me what the warning is it's saying there's a non-additive animation on the mm land so let's open up the animation that was uh retargeted for us so that's the mm land and let's compare it with the U mannequin animation mm land so there seems to be a bug here where some of the uh additive settings are not copied for example here the local space frame from this animation and the frame rate is not uh copied over so we just need to copy that over manually on our character here so under additive settings here change it to local space change that to frame from this animation and then it's 26 frames I hit save and play this now so when I hit on jump my animation Landing for jump is now fixed so the other thing that we need to fix and then we're done is the foot ik so I covered this on a previous video but I'll quickly cover here so we need to add some bones uh so basically on my skeleton here I need to add some vertual bones um which would act like ik bones so um if I go under root here right click and select ad veral bone and search for uh yep left foot that would create a virtual bone for me on that position and then do it again say add virtual bone say right foot and now I have two veral bones cool um if you want more details on that check out my previous video so now I'll go to the mannequin rigs here and look for the CR mannequin basic foot ik we're going to duplicate this so we don't have to recreate everything and I'm just going to rename this to CR race and I'm going to move that to the mixo folder cool so now let's open this up so compile uh just to remove that warning but basically we want to swap out the mesh so right click on the root here select refresh select mesh and then select your uh mixo C somehow it closes that window so let me open it again and now you could see that the charact the mesh is now in the viewport here and at the bottom section here I have those um veral bones so if I go look into this graph um it's doing a line trace on the virtual bones so you need to replace those ik foot bones with the virtual bone that we just created so this for the left foot this is for the right foot and and I think on step four do it again there VB left VB right foot and for the this modified transform um node replace the pelvis with the hips because our character is using uh that naming structure and do it again here for the bone get the VB left foot VB right foot and then for the actual full body ik here specify the actual bone so this is the hips and then for the bone here so we have left foot and this one is right foot compile save now go back to your animation blueprint and let's go back to the anim graph and now we could connect the control rig but first we need to define the class that we just created so under control rig class here change that with the class that we just a control rig that we just uh created now you could wire this up when I compile our character snaps to the ground which is what we want save and now let's test this out so now when a character walks on the ramp the foot ik is now working job is working as well and all that good stuff so one thing I want to test as well is the um animations so if I go under animations here for the hip-hop dance I'm going to create a anim Montage for this one save go to my uh third person character go event graph and I'm just going to create an event here say keyboard T and when I press the keyboard I want to play an animation and the animation montage is this dance compile save and let's test it out so when I hit T character should dance do the breake dance move cool how cool is that so there you go how to add a root bone to your character and then we target animations and then um fix some of the retargeting issues with it so hope you like this video thumbs up thumbs down please subscribe to the channel cheers bye for now

Channel: Just Another Dang How To Channel

Views: 2,563

Keywords: unreal engine 5.4 tutorial, root bone on mixamo skeleton, animation retargeting

Id: S3IYchXN_B8

Length: 17min 5sec (1025 seconds)

Published: Thu Apr 11 2024