Sorry for the delay @Beardilocks, bought targeted on work and my response was placed on the backburner.
So along with associated particles enjoying on the character(s), if you need one thing enjoying on the physique with out establishing the consequences within the character’s materials, you may spawn chunks of geo onto sockets of the character, with these chunks utilizing the 1-x Depth Fade technique you talked about in an additive materials. You’d have these positioned contained in the character’s geo. I did this for some R&D for a therapeutic merchandise in Remnant (I believe it truly made it into the sport…). With this technique, you may simply have a collection of particle programs in your standing results together with the additional layer stuff like smoke or sparks, without having to manage any supplies or their parameters by way of BP.
Some caveats with this technique could be needing extra intensive BP setup or code assist if in case you have completely different characters with distinctive skeletons, as they could have completely different bone names. For this reason I all the time use sockets for all my work, since any skeleton can have a “VFX_Head” socket title. You might also run into points if in case you have characters with vital dimension variations, then you could want completely different sized meshes for them, or some form of resolution throughout the materials, like WPO to scale the geo up or down a bit.
One other technique is having your standing stuff in-built to your character grasp materials, with switches for every completely different standing, after which having materials situations with these options turned on. You could possibly simply swap out your foremost mat occasion for whichever standing one you want, after which swap again to maintain your base instruction value low. I did this in Darksiders for when an enemy would die. We’d swap to a “dissolve” model of the fabric and erode it out whereas enjoying particles with it earlier than the enemy was faraway from the sport. The downsides of that is clearly you would want every new character to have these situations made solely for it, and the extra standing results, the extra situations you’d must make and arrange. (Vimeo’s the worst, click on to 1:19 for the instance)
Since you possibly can’t toggle materials switches on the fly, as was beforehand talked about, you may probably have all the pieces constructed into your character grasp shader. To swap between issues although, you’d most likely have a bunch of Lerps as a substitute of switches, after which simply toggle a given standing lerp’s alpha enter param between 0 and 1. This might imply each character is all the time carrying these extra texture pattern lookups and directions round with it, and there’s nothing stopping the fabric from unintentionally having a couple of standing lerp parameter set to 1.
My final suggestion, and one thing I’m at the moment utilizing for just a few enjoyable issues is @Bruno ‘s possibility B. I want I may share my actual setup and screenshots, however my fundamental movement is have a separate Blueprint Actor you possibly can spawn. In that actor you might have an empty Skeletal Mesh part to focus on. You’ll solid to your character, get its skeletal mesh and use “Set Skeletal Mesh” along with your empty because the Goal. The important thing node to set after setting your skeletal mesh is “Set Grasp Pose Part”. That node will mainly mirror all of the bone actions from the character you solid to onto your new BP actor mesh. From there you possibly can set your materials on to that mesh, and also you’ll most probably need that as an additive materials. This lets you mainly spawn a clone mesh on high of your chosen character. Whereas your overdraw will most probably be very minimal, you’re doubling the variety of animated skeletal meshes, bones and all, which can be enjoying and updating directly. Moreover, there are all the problems Bruno talked about, so I don’t know the way this is able to react to issues like material, physics, ragdoll, and so on.
Beneath I added some screenshots and a video of a wip materials I threw collectively as an indication. It’s not excellent, but it surely’s based mostly on display house UVs and makes use of the geo’s normals for a fresnel that bends the feel across the mesh a bit so it doesn’t look flat. This might be used over a personality without having any particular UVs arrange, so you may apply this to nearly any cloned character mesh as is. It falls aside a bit at excessive angles, like wanting straight down, but it surely provides an honest end result from common viewing positions. All you want is a noise texture of your alternative and a colour LUT or Lerp.
I’ve this enjoying on an Opaque/Lit materials simply to provide a greater really feel of the way it seems to be on a textured and lit character, however this is able to most probably be an Additive or Translucent Unlit materials you’d play on high of one thing.
