Get Mesh's Distance Fields Texture?

Hi, my intention is to use the static mesh or skeletal mesh as the distance field data for raymarching.

Looking at this Unreal training, link text Ryan created a material with a CustomExpression to do the raymarching, but that expression also takes in 3 sphere parameters which are SDFs. So my intention is to remove the 3 sphere parameters, use the mesh’s SDF, plug them into a Post Process to create “metaball” effect of any mesh with the Post Process material on.

Example use case: A skeletal mesh walk towards a sphere and as they get closer, they will form the “metaball” effect as if both of them extending out to pull each other in.