High Heels and flat feet help

hello guys i need a little help with a character customization system and "characters using high heels or flat feet on animations.

ok my questions is on 2 cases:

case 1 modular character - ok i have a modular character break in 7 pieces: head, torso, arms, hands, hips, legs and feet, my issue is which i want to use some high heels shoes as one of the options or flat shoes as others options, all the pieces come from the same “base skeleton”, i have the full character skeleton and its break in pieces(only the mesh), all pieces have the same full skeleton to when export to unreal to use exactly the same skeleton, but i have 2 diferent "reference poses one with flat feet and another with high heels, my question is how i can make the engine switch when “applying” the high heel feet pose, from the flat and backwards.

case 2 i have 2 versions of the same character one using high heels and the other flat shoes the question is almost the same as the 1, how i can use the "flat shoes animations in the high heel without having to have 2 different skeletons and 2 diferent "set of animations, i means make one animation work for both high heel and flat without issues.

if both case 1 and 2 can be fixed in the same way then it would be perfect, i know which we have the "master pose component to do something like that but i’m still a little new about it, then i would love to know if anyone could give me a little tutorial about that: how to make a character switch between those diferent types of “foot pose” using the same animation and maybe skeleton without need to have "duplicated versions of it(skeleton and animations or maybe only animations if i need to have the duplicated version for the “diferent pose”.

Because ALL the animations will be constant you can raise the feet by the heel amount.
You do this by just shifting the whole mesh (master pose) up however many centimeters.
You then have to apply a rotation - i would suggest a corrective animation, as it would be best - to angle the feet according to the shoe. Or, you could replace the feet mesh.
if you just weight paint the mesh to use the flat position it would be fine.
you just need to shift the feet down without altering the bones.

Keep in mind, walking in heels should probably be its own animation…

it’s means which i must have 2 animations? one for high heels and one for normal? or maybe i can use a "morph target to adjust the feets whenever a "high heel is being used?

You don’t have to have 2 animation. If you build correctly you can apply an additive corrective to change the rotations of the feet.

What we’ve done before is simply eat into the shins. The shins are shorter when you wear heels. It works, but it’s not beautiful.

What I would do if I was after top realism, would be to create override animations for shoe kinds, that affect the ankle/foot/toe bones, and angle the ankle down. This could also affect the entire lower body if you want a more rolling gait when wearing heels.
I would then also have some offset on the character capsule to compensate for the feet sticking down further.
Or animate locomotion/height based on impacts with the actual skeleton, a knee/hip straightening torque, and some kind of constraints to avoid the character toppling over.

That unfortunately leads to foot sliding, unless you also fix it up with IK and “gluing” the feet to the ground. And even if you do that, you may end up with snapping when engaging/disengaging.

So a few assumptions.
You know what you are doing with IK, and you know that OOP in animBP matters a lot.

Move the ssocket used for trace to the ball.
add a float for heel length.
If you do not have one, add a float for shoe height.

Get into your IK math and offset the hit by the shoe height.
on the hip result too.
Add to the hip the value of the heel as well.
This moves the body up and causes the character to float - if you stop solving anyway.

Apply after the leg IK the additive for the heel, this shifts the point of the cast to where it should be - so make sure you took the heel height values from the animation! The more they match, the better it will look.

If you haven’t done so already, make the precision of your IK solvers Very low (Integers work for me).
The lower the precision of the solve, the least snapping it will cause - as a very general rule of thumb for any IK.
a result within 2cm is usually not visible as an error on most third person views.

last but not least, consider adding an additive for walking in heels to modify the base walk cycle when heels are worn. It may be easier then shelling out a specific animation.

If you don’t know what IK is, then maybe you shouldn’t be overly concerned with heels or no heels…
Just make your specific animations for walking with the heels, and it will probably be good enough.

wow interesting i’ve forget about the ik solve maybe it can work, the thing is which i’m currently with 2 projects one small to help a friend with a school project, he is making a demo hack&slash game with 2 levels then he wanted to have 3 variations of the female main character and one of them was using a high heels skin, the player start with one and will be able to unlock the others 2 playing the game.
here a exemple:

(those ofcourse are not the final models just to show the difference)

then we wanted instead of have 2 skeleton meshes each one with they own animations, animations montage, animation blueprint be able to use just one and adjust the feet angle in a blueprint,

the reference pose is already made and we gonna retarget some mixamo animations, we already tested the animations with each model and they worked fine, it’s just we want to “simplify” and have only one set of animations and blueprint to be used by both and don’t have to use 2 diferent sets of stuffs, ofcourse if it would be possible.

https://imgur.com/ZlW4GNj

You can probably change the weightpaint of the feet - eliminating the paint for the toe by joining it to the foot.
Without changing the skeleton.

The height shifts up.
Use the root bone to keep adjusted.
the feet will then hang below.
thats perfectly fine.
Just adjust your character bp to slide the mesh upwards by a matching amount when you make the mesh swap.

hmm ok, really thanks i will look on that, to be clear we do have a “morph target to adjust the feet angle”, then maybe we can throw the morph in the blueprint to “adjust” the feet angle when the heel model is choosen

Another note both models are basically the same, they are not 2 diferent models, it’s the same mesh with a skeleton"skeleton" which have a heel adjust morph target it’s just using diferent outfits and "adjusted feet, they are not 2 different models in the sense of being 2 meshs is a single mesh using 2 different outfits, one with heels and another without.