Akeytsu tips & tricks #1

Tutorial / 16 April 2020
  1. Combine Update skinned Mesh + retopology to skin perfectly with ease. This also works great with cloth : if you have to skin a "thick cloth" with volume between back and front faces, simply skin a single-sided version of that same cloth and transfer its skin weights to the final mesh ;)  

    Here are the steps of the video below :

    1  duplicate your "issued" mesh
    2  unbind it and export it to 3DCoat (import it as reference mesh for retopo)
    3  perform a clean retopo on one side, apply a symmetry and export it in fbx to Akeytsu
    4  Import new retopo mesh in Akeytsu
    5  Duplicate the whole existing character and remove any useless meshes
    6  take both skinned mesh (from duplicated character) and retopo mesh, then perform an "update skinned mesh". You should now see your retopo mesh skinned "badly" (in fact it's just your previous issued skin)
    7  hide first character in order to focus on retopo mesh
    8  smooth like a fool, be generous in your strokes ! Tip : I used a looped macro that does click THEN release click so the brushing feels more natural ;)
    9  show back your original character
    10  select root joint of your "retopo character" directly from the tree, then select all its vertices and hit "Alt+C" (copy weights)
    11  select now the root joint from your target mesh, the original, and select the vertices you want to paste values to (select larger areas, no matter if it hits other areas especially if they're rigid, you could clean them after all)
    12  hit "Atl+V"
    13  you're done ! 










    1  duplicate your "issued" mesh 2  unbind it and export it to 3DCoat (import it as reference mesh for retopo) 3  perform a clean retopo on one side, apply a symmetry and export it in fbx to Akeytsu 4  Import new retopo mesh in Akeytsu 5  Duplicate the whole existing character and remove any useless meshes 6  take both skinned mesh (from duplicated character) and retopo mesh, then perform an "update skinned mesh". You should now see your retopo mesh skinned "badly" (in fact it's just your previous issued skin) 7  hide first character in order to focus on retopo mesh 8  smooth like a fool, be generous in your strokes ! Tip : I used a macro that does click THEN release click so the brushing feels more natural ;) 9  show back your original character 10  select root joint of your "retopo character" directly from the tree, then select all its vertices and hit "Alt+C" (copy weights) 11  select now the root joint from your target mesh, the original, and select the vertices you want to paste values to (select larger areas, no matter if it hits other areas especially if they're rigid, you could clean them after all) 12  hit "Atl+V" 13  you're done !
  2. Use mixers to animate step-by-step. It's probably the most memorable trick Aurélien Charrier showed to Akeytsu users. When you have to make a walk, you have to focus first on pelvis movement, then legs+feets, then the trunk, head and finally the arms, details like hands or facial expressions comes at the very last polishing pass. Iterate

    For this 4 legs fast-paced walk I had to think about how the body moves, how the weight translates, and all this considering I'm not a full-time animator (despite I really enjoy making animations ^^). If you look at the Vulture droid's legs and how it's articulated, you not only have to deal with 4 simple legs but two pairs of legs linked to R & L kind of clavicles, but as stated above, I worked by iterations and this saved me from hours and hours of working on crap tons of keyframes ^^ Here the walk consists in 2 keys (3 & 4 are phased versions of 1 & 2), the head is slightly animated on top of it so I can have this look around/checking peoples movement which was initially done by Thomas Chaumel (for those who do not know, he is the animator behind Star Wars Redemption ;))

Once you're okay with the base, everything else follows quickly. Here I do not used any IK/RF solvers, everything is made using good poses :)

3. Add twist/roll joints to your limbs (arm, forearm, thigh, calf...you name it !). It's not fully automated but still pretty simple to achieve, here's an example I gave several times on Nukeygara forums :


> For more convenience, align perfectly this twist joint to the disconnected joint he should twist from (here, the wrist), so when you twist your wrist, take the twist joint too and you'll achieve a perfect twist ;)

4. Load custom rigs instead of UE4/Unity ones. To do so, simply replace FBX stored in "C:\Users\Public\Documents\akeytsu\Templates" (keep the same names so akeytsu could find them). You can also replace icons if you want by editing what's in "C:\Program Files (x86)\nukeygara\Akeytsu\Resource" ;)
This can be helpful to load full rigs with a base mesh already skinned on it to tackle tons of characters skinning by using the update skinned mesh command =)


  5.Allow the tip toe joint control. Yep. It's THAT simple (Thanks to Addison DeBolt for showing it on Nukeygara forums) :


  6. Skin face joints using a mask mesh. Why ? Because doing so will allow you to transfer perfect weights to your final face mesh, of course you'll need to test & tweak the result, but it's far easier to skin "without thinking" at first and spend the less time possible on manual edits ;) This mask should be done outside of Akeytsu in a retopology software, take the one you love the most (my choice goes with 3DCoat). When creating your retopo skinning mask, keep in mind that each vertex will later have to match a joint. The skin weight transfer will then transfer a lowpoly weighted mesh to a "higher" one, so each vertex which falls inbetween two joints will simply receive the exact weights that technically exists between two distant vertices =)


  


  7. Proper orients.
That's the base of a cool rig to use. I've made an article for nukeygara about how to create a simple facial rig based on joints : https://www.nukeygara.com/blog/create-a-facial-rig Everything told here applies heavily to any other part of a rig (not necessarily a human one). It's a logic of who controls who. It can be a joint controlling other joint(s), a joint controlling a group of vertices, and most important : keep in mind that a joint is just a simple keyframable pivot, and a simpler way to manipulate geometry =) Rigging can be tedious if you don't have a good toolset, hopefully Akeytsu offers well-thought tools that ease the process a lot !

8. Smoothing out your animation.
If you encounter some jittering/imprecise transforms at some point of your animation, there are a few things you can do to fix that. The most obvious one is to open your curveboard and check for abnormal peaks, starting from the master joint and descending throughout the hierarchy after each fix until the very end. Yeah, tedious (even in Akeytsu). Another thing would be to avoid having tons of layers with timing offsets, because it will end up creating bad interpolations when the whole stack will be mixed. The thing I use a lot, is the tween machine. Since it's out, I simply take the keyframe that has a bad interpolation behavior and then I "tween" parts (still from master joint to the last one in the issued part of the hierarchy). Doing this avoids opening the curveboard and fixes all transforms at once instead of going through one by one ;)   


  That's all for this one ! Tell me if this helps you on using Akeytsu, and if you need specific explanation of some tricky points ;)