Refactor CR_Als pelvis offset to handle differently sized skeletal meshes

[corbin-poteet]

Howdy!

I made a fork of this repo to convert the plugin into a Game Feature Plugin for Lyra and I ran into a tiny issue with the current implementation of the control rig. Lyra's characters use an invisible skeletal mesh and attach cosmetic actors to it using a "Copy Pose From Mesh" AnimBP node to match the cosmetic skeletal mesh to the character's main skeletal mesh.

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Desired Results

This works fine with Lyra's CR_Mannequin_FootPlant control rig-

SKM_Manny (exact same size skeleton as the parent skeleton):

SKM_Quinn (different size skeleton):

Current Results

But with ALS's CR_Als this results in smaller skeletons hovering and larger skeletons crouching-

SKM_Manny with CR_Als's preview mesh set to SKM_Manny:

SKM_Quinn with CR_Als's preview mesh set to SKM_Manny (you can't see it in the picture obviously but it literally hovers up and down):

SKM_Manny with CR_Als's preview mesh set to SKM_Quinn:

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I assume it's something to do with how the pelvis offset is handled. Comparing CR_Als and CR_Mannequin_FootPlant, they have pretty similar pelvis offset functions. I've tried a lot of things but I can't for the life of me figure out what exactly would need to be changed, I saw you were working on a 5.7 update so I figured you'd might like to take a look at it.

ALS's CR_Als:

Lyra's CR_Mannequin_FootPlant:

I know this is somewhat outside the scope of ALS, but I think it'd be a worthwhile change as this seems to be how Epic does cosmetics in Fortnite.

[colorindarkness]

You could also use Corrective Poses in cases where the Mesh has very different proportions