Extended interpolation not working

[lean bear]

So im new to live2d, and have been working on my model, and made the mistake of using a rotation deformer without knowing that meant I couldn't use warp deformers on that object afterwords. After moving the parameter from the rotation deformer to a warp deformer, I noticed the object would shrink and warp and then get bigger when moving to parameter points.
To fix this, I was recommended to change from linier interpolation to ellipse interpolation so things would move on the arc sort of shape. I saw a tutorial video on twitter for how to do this, did it, and effectively nothing changed, so clearly im doing something wrong.
https://i.gyazo.com/de63404d15a4f79089e89d84706ff15a.mp4
assuming this video link works the eyelash selected is the only one with a rotation deformer converted to a warp deformer (and converting the other rotation deformer to a warp deformer also gives me a problem with how the object behaves as well)

Can anyone give me any help for making these objects properly move?
https://x.com/pixelvertice/status/1422982651791564804
this is a link to the twitter videos I was recommended for trying to make the objects move correctly

Ran 🐲 Live2D Animator (@pixelvertice) on X

[Live2D Protips]
By default, params in Live2D moves in linear trajectory. Which made some parts that supposed to bend in arch (eg. hair) may looks... stiff. This is where 'Extended Interpolation' comes to rescue!

Twitter · Aug 4, 2021, 6:07 PM

idk if any of this is helpful at all either

[pastel coral]

i believe part of your issue is due to the child moving outside of the parent deformer

[lean bear]

wait what do you mean by this? is there any way to fix it?

[pastel coral]

when you have 2 objects [can be deformer, mesh]
A inside of B
A is a child
B is a parent

Child's should never move outside of Parent

your deformer green is child of that other deformer [red arrow]

[lean bear]

oooooh I see what you mean

is there any way to fix this?

I may have rigged the eyelashes poorly now that I look at it, as its one of the first things I did on the rig

[pastel coral]

well, the way to fix would be re-rig that pieces that are not compatible,
by a rule of thumb you always want to make sure that child is inside of parent in all of its movements

[lean bear]

I I feel like this might be a mistake in itsself with what ive done

[pastel coral]

mm i dont see a reason why you have the parent deformer and the mesh both rig on eye open

[lean bear]

as the art mesh and a warp deformer are both on eyeR open

yeah I removed the parameters for the art mesh and nothing about the movement changed at all

https://i.gyazo.com/6a77185631aa61b65efc6681a1bc07e6.mp4
but the eye close open after changing from rotation to warp did do this to the eye thats super annoying

[pastel coral]

mm you dont want rotators there, they are gonna limit you a lot

btw you have physics for the eyelash?

[lean bear]

yeah im learning that. At the time when I started rigging, I didnt know adding in rotation deformers would do this to the model

oh yeah I got super cute eyelash physics

hangon lemme get a lil vid

[pastel coral]

i feel you should made the physics on the mesh
then a deformer for the eye open-smile [big enought so all the physics movement dont make the child go out

[lean bear]

https://i.gyazo.com/3b604403324bb1753f200e72e7da2fa5.mp4
there we go

so in short, I basically gotta re-do everything

well now im not sure
when I delete everything on the eyelash except the eyelash itssself and one warp deformer, one that doesnt have the child move outside of the parent object, interpolation still isnt working when I change it to ellipse

[pastel coral]

i dont recomend you to do extended interpolation like that, its creating a lot of mini keyforms there

what is the objective of that extended interpolation? why do you need it?

[lean bear]

https://i.gyazo.com/240b4342dec1ed5db6022ecb24abfea6.mp4

well yeah but I at least wanna see that it works at all instead of having all these shrinkage issues when anything moves

[pastel coral]

ok but your shrinkage is not because of curvature [what we use extended to fix ]

your shrink is because you literally flipped the warp

[lean bear]

Im basically trying to have the eyelash rotate but not on a rotation deformer so I can continue to work on it with various warp deformers

[pastel coral]

this you are flipping the warp deformer over itself

[lean bear]

it, its flipped because originally it was on a rotation deformer so it just turned 180 like the other eyelashes there are

[pastel coral]

this is not an interpolation thing

so extended interpolation is not gonna do anything here because thats not the issue

you have to re-do the parameter for that piece so it rotates instead of flipping [or flip and make sure it does is in one axis only and not in both]

[lean bear]

I, I dont understand fully

[pastel coral]

ok

let me doodle

normal interpolation moves like this [imagine each black line is one keyform
and the red line is how the tip is gonna move

when you use extended interpolation, it creates a "curve" movements
so now the tip is gonna move like this, like an arc

what you are doing is flipping the warp [i colored each wall of the deformer with a diferent color so is more visible the before and after position]
as you can see, on the middle of that movement it shrinkgs because its flipping completly over itself

instead, you want to flip it ONLY on one axis [this means, only like a mirror] so when it "flips" it will look like a paper rotating, as you see, it dont shring everywhere, but only like squish on that axis, then extend again

[lean bear]

but what if I do want it to spin, to rotate, instead of squish

[pastel coral]

then you need to add a keyform on the middle

[lean bear]

-goes to do this real quick-

[pastel coral]

something like this

if you want it to rotate then you have to add a key on the middle to make the arc

[lean bear]

I did it and it isnt like, folding onto itsself, but it still shrinks and then re-expands between keyframes

[pastel coral]

can you take a video?

[lean bear]

yeah I can

I would say, on the first post here with a link to the twitter posts, the lolipop video is a good example of this, where it shrinks halfway between each keyframe
except ellipse interpolation literally does nothing and thers no arc or circle that appears

[pastel coral]

yes but i want to see your case specificaly

[lean bear]

its a bit harder to see cause its less extreme than the loli, but it is there and it bugs me

https://i.gyazo.com/196f09dba8f9a680c5c0fc82d37c4f45.mp4

[pastel coral]

ok, first, can you remove the extended interpolation

also, the best is you start simple, you have too many keyforms right now, start simple, only 3 keyforms as the doodle

[lean bear]

I switched it back to linier interpolation

because of how the eye opens and closes i am uncertain if I can do only 3 keyforms on the eyelashes
because it took that many keyforms to make the eyes open and close properly because of their shape (initially with help from this discord server, after a lot of problem solving)

[pastel coral]

you want this first

[pastel coral]

It is fine if you need more later
but the objective is

"Start simple"

if you dont have a good structure and start adding more and more keyforms, that looks like you are lost and not knowing what to do and try to fix by adding more and more

[lean bear]

https://i.gyazo.com/55b37649ae708e8829c650ce58ebc7d9.mp4
heres how it functions with only the interpolation changed back, same keyforms

[pastel coral]

is better
to start simple, then refine later

[pastel coral]

ok, right now something visible is that in alot of those keyforms you are scaling down the deformer, is not the same size

[lean bear]

it looks the same size on the keyforms individually tho

at least I think it is
it should be though as this is from a rotation deformer with parameter values copy pasted to a warp deformer

[pastel coral]

teoricaly there is no reason for the way it moves on the first two pictures, you want it to rotate out, not, in then out

but again, start doing 3 keyforms, then later on we can see where do we actually need more or not

[lean bear]

I have it at 3
0
0.5
and 1
(1.2 being eyes wide open but I took it off for now I guess)

[pastel coral]

mmm i dont feel the eyelash should rotate in when closing eye

[lean bear]

https://i.gyazo.com/970c4b2f8795d52d91d0aba4dd782796.mp4

[pastel coral]

that is happening because on 0.5 you rotated clockwise instead of counterclockwise

eyelash always should point out [more if you think about the fact they are over a curved surface like the eyelid over the eyeball]

[lean bear]

https://i.gyazo.com/05e4be1405f7ea2965bb18e6cda7b7a9.mp4
I adjusted it and nothing helpful of note changed it still moves wrong

it doesnt 'flip' but ya know, massive shrinking

[pastel coral]

yes, it does, thats normal, first you need to fix the keyforms, then the interpolation, dw, what you see right now is normal

[pastel coral]

right now we are doing this

[pastel coral]

for example here on 0 is not that "down" as you did

the idea is we are building the structure keyforms first, then once they are good, then we are gonna fix the interpolation

[lean bear]

are these keyforms okay?

[pastel coral]

the last one should be more rotated, it looks too straight

[lean bear]

I do have a question
because I save my model as seperate saves as I progress (incase I make a big mistake, I can backtrack to a previous save file of it)
reason why I was moving rotation deformers to warp deformers is the eyelashes were unable to warp deform when I added the face rotation
could I delete all the deformers for the eyelashes, add the warp deformers for different angles, then copy paste the previous rotation deformers from a previous rig save file onto the new one after the fact?

[pastel coral]

a little like this [maybe not that much i just used paint]

[lean bear]

the current rig us save #6 so there are 5 previous versions

but I like, how it sticks out with the eye closed

[pastel coral]

you want to delete all deformers, then make another for angleX-Y, and then add the rotators again?

you dont want rotators there

[pastel coral]

ok then

this means you need 1 keyform at +0.25 to make a middle position between 0 and 0.5

you create the keyform, then copy the shape of 0.5 and fix the position

[lean bear]

this is effectively what I was initially thinking yes. just, delete everything I did on the eyelashes, add a warp deformer for different head angles, then copy paste the rotation deformers from a previous model save onto the new model save after the head angle warp deformers are done
I dont know if this software works like that or not though, but Ive heard of other riggers using completely different rigs to speed rig new rigs

[pastel coral]

you can copy things yes, but you dont want rotators there

[lean bear]

why do I not want rotators on the eyelashes?

[pastel coral]

because Rotators, cancels parent deformation

Rotators are basicaly 1 pixel only
so you can not Deform 1 pixel

if you put a rotator there, all deformation over it will be ignored

and will look bad

well not bad, but out of place

[lean bear]

so if I have a previous deformation, and then add a rotation, the previous deformation will fail to behave properly?

[pastel coral]

dont matter what you do first or later
If you add a rotator
anything on top of it that involves deformation, will be ignored

[lean bear]

wait
so anything below a rotator, like a warp deformer, will it actually deform properly?

[pastel coral]

just to make things easier for future
Here we use Parent system
A parent is an object [can be warp/rotator] that has something inside of it
an object inside a parent is called "Child"

A rotator will ignore any Parent Deformation because a rotator is 1 pixel, so it can not be deformed
you can deform childs of a rotator, but that may give results you dont want because they will also be affected by the rotation movement of it

[lean bear]

I am going to, keep this in mind thank you

but continuing where we were

[pastel coral]

yes, did you added the 0.25 keyform?

[lean bear]

how do I copy the shape of 0.5

ye

[pastel coral]

ctrl shift C/V

thats the shortcut to copy shape

[pastel coral]

that means you tried to paste without copy first

[lean bear]

I did the copy first but it just opened gyazo

different app

[pastel coral]

gyazo?... do maybe want yo change that shortcut on gyazo or on live2D as you maybe cant have both

[lean bear]

is there anything I can just like, click to copy instead of a shortcut

[pastel coral]

menu>modeling>editform>copy shape, paste shape

[lean bear]

ty

so now I just adjust the 0.25 form?

[pastel coral]

yes

[lean bear]

https://i.gyazo.com/daef18b0b09732d32bd77ff12de8387c.mp4

[pastel coral]

ok, because how 0 is very extreme
you can adjust 0.25 more, or add another keyform in the middle of those two

[lean bear]

this far okay?

[pastel coral]

you need to test how it moves from one key to another to see if you need more or less

[lean bear]

https://i.gyazo.com/19645134b8f6be43891681f5376e7766.mp4

[pastel coral]

that looks a lot better and softer

[lean bear]

theres still shrinkage though

[pastel coral]

👆

basicaly that logic

The more "Extreme" the keyforms are, the more you would need to fix

[lean bear]

so the fix for shrinkage is just, more keyforms?

[pastel coral]

but only the necesary ones

[lean bear]

do we uuse interpolation adjusting here at all?

[pastel coral]

you dont need it

also the more keys you have, the less you want to use extended interpolation
but the more extreme the keys are, the less the extended interpolation will help [or would do diferent things, because it calculate everything based on the current keys]

extended interpolation is not just a "magical fix to curve movement" but is just a soft calculated keyforms inbetween the real ones, based on the real keyforms to create the others

[lean bear]

I do have to ask though
in the videos when the user clicked it on, it showed an arc or a circle but mine stayed a square
why did theirs behave correctly but mine didnt?

[pastel coral]

yours stayed square? what you mean?

[lean bear]

I mean when this person selected it it showed them a circle

and I think all the dots are keyforms on the parameter?

this is why I thought this would work, because it looks like it kinda mimics a rotation deformer, without actually being a rotation deformer, so maybe I could fix the shrinkage

https://x.com/pixelvertice/status/1422982686084239362

Ran 🐲 Live2D Animator (@pixelvertice) on X

Or when you are trying to rotate a warp, you may notice the warp is shrinking in between the keys.
You can also use Ext Interp in this case. The function 'virtually' adding more keys to your selected parameter to create a better, curved trajectory.

Twitter · Aug 4, 2021, 6:08 PM

because it appeared to do that on their video gosh why did it paste as an image

[pastel coral]

the visualization of the movement?

thats onion skin

on the bottom of your canvas, you should be able to see an icon that looks like 3 circles of diferent grey

there you can click the menu, there is settings

and on the settings there is an option called something like orbit of selected vertex

[pastel coral]

that show you how that vertice that you have selected will move [you can see on their videos they have selected one or two vertices of the warp deformer

[pastel coral]

click ok

[pastel coral]

yes

that one

[lean bear]

do I need to adjust to anything? I had it like this already

[pastel coral]

its fine

[lean bear]

by vertices do you mean the keyforms?

[pastel coral]

no, vertices are the dots of the artmesh/center of rotator/ dots of warp deformer mesh

for example on the video, they are selecting that one

you can see its highlighted

[lean bear]

wait, so does this only work on a mesh and not a warp deformer then?

[pastel coral]

thats a warp deformer

he is selecting a vertex of the warp deformer

[lean bear]

but mine are all green exceot the middle ones

so like, if i were to try to select the top middle of the eyelas, I cant

[pastel coral]

the green are called beziers

you can see where the lines of the mesh touch, there are little "dots" those are vertex

[lean bear]

oh, theres no vertex's going through the middle are there

is it because the warp deformers are made like this?

wait I can make it look like this

THATS HOW IT WORKED THIS WHOLE TIME?

fascinating fascinating
but I see what you mean where it doesnt really make it 'rotate' it just kinda, smooths it out a bit instead