Creating dynamic terrain with morph targets and per poly collision

I am exploring the feasibility of different design ideas and I was hoping for some advice/troubleshooting help. I want players to fight on a dynamic open-world type landscape. I know the Landscape feature itself is static, so I thought maybe it’s possible to create a large dynamic mesh that uses morph targets to transition between different battlefield states.

I am having trouble testing with a simple 2x2m cube that morphs between a flat top and a rounded top. I would like to see the player character move up and down with the cube’s transformation. The cube was imported from blender with only a single shape key on it; there was no skeleton on the model before import to UE.

I am using the default ThirdPerson base game and the ThirdPersonCharacter BP. For the cube, a blueprint with skeletal mesh component ‘BoxMorph’ has the skeletal mesh ‘shapeKey_Test’ assigned to it. shapeKey_Test has a default physics asset assigned to it, ‘shapeKey_Test_PhysicsAsset’, with a capsule collision component.

The blueprint sets the morph target value ‘Key 1’ using a timeline loop. BoxMorph has the following settings:

  • Simulate Physics - Off

  • Phys Mat Override: None

  • Character Step Up On: Yes

  • Collision Presets: Custom - Collision Enabled, WorldDynamic, All object responses blocked

  • Enable Per Poly Collision: Yes

There is a change between on and off for enable Per Poly Collision here: When off, the character interacts with the default capsule. When On, the character is standing on the flat surface of the cube’s base pose. In either case, the character is not being affected by the cube’s morph. When I originally adjusted the per poly collision setting in the skeletal mesh ‘shapeKey_test’ there were no changes, so I guess the BP overrides these settings?

So it looks like this is kind of working, but the morph target animation is not affecting collision. Is there a way to make this happen? Do I need to use bones to make the animation affect collision?

This CANNOT be done in Unreal without using a special script ( in MAYA - in my opinion this is an embarrassing shortcoming for Unreal. This and the lack of procedural landscape generation in general. For such a fancy looking engine, it’s quite limited.