How do I sync Morph targets (Shape keys) when I need one to ramp up faster?

Development Character & Animation
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UE4.27 and Blender 3.6:

Blender > I have pants that will expand with a Shape key = “Expand,” and I will use the same shape name for other meshes to move in sync (when in UE).

And I made a belt Shape key that matches the verts of the expanded pants.
My goal in UE is to have a blend from 0 to 1, thus 0.5 will be possible on the Morph target verts (when displayed in game).

  • But in Blender > I test animated the keys from 0 to 1, and the belt lags behind (at 0.5 the belt doesnt expand fast enough so it clips into the pants. Yet at 0 or 1, they look correct).

  • So since I can’t use Blender’s Drivers to ramp up the belt Shape key faster than the Pants (cant import Drivers into UE?), then what can I use in UE to make the Belt shape key (now a “Morph Target”), ramp up faster - when they are named the same thing?

  • Or should I name the belt shape key “Belt” (so it’s different than “Expand”).

  • And then in BP > make the Belt key ramp up faster than Expand, by using a multiply node or sharper Timeline (so it reaches 0.5 and 1 faster)?

  • Thus in BP, I would have 5 meshes reacting to “Expand” (in sync), while Belt has separate code to drive it to 1 faster.

  • Or is there an easier solution? Ty

2

Skyrim mods have such system. You should see some tuts about it (how to morph for body mesh) to get idea how that all works.

They do cloths morphing by starting from body mesh (together with all morphs). Then they modify that mesh into piece of cloth (however most mods nowadays use some existing armor piece as start/base). This way both body and cloth have same morph
values. In skyrim it is all much more complicated because there are like 40 morph sliders.

Other than this (for new meshes) it is all manual job of painting weights on mesh and adjusting them to match)

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Can you give a starter link? I dont know the terms for Skyrim, current version, etc.

I know how to weight/make morphs. I am asking how to drive the different change (different meshes, same Named effect) in UE code - because Blender has drivers, but we [cant] import the formula into UE.

4

You can drive morph target values from blueprints, maybe from animation blueprint also.

With different meshes problem is that you need to recalculate one morph target values to another mesh morph target. And for this i do not know about any automatic way, I only know that skyrim has tool for it, and modders there do it all manually with that tool.

for skyrim there is tool, google for: “skyrim bodyslide studio convert” warning most results not quite work safe :wink:

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