Soooooo, lets say I have a HUGE mesh (respectfully huge lets say 40k verts)… and with that mesh I have the ability to ID certain vertices (a vertex Group). Now lets say I want to do a blend mesh for that mesh, but its very specific say only in an area where 800 of the verts or something get modified.
Is there a way to make a blend shape where I don’t have to have every single vert of the first mesh in the secondary blend mesh? Ideally only the vertices that were modified.
If there is not a method for this I have a couple solutions but I don’t want to take the time to dev them right at this moment.
Basically I am trying to avoid making my file-size bloat by modelsize*blendshapes…
Hi.
Last time when we tried, we ended up splitting verts which need to be blend in a different mesh and add blends only on this mesh 
can you explain this more?
Sure. We had to do this for a character, and because all the blends was around mouth and eyes, we spliced in 2, the head and body, and add the morph to head only. Was a little bit tricky with the animation at the end, but finally we managed it to work
hmmm, that might be a solution…
I was worried about doing it on the GPU because the displacements wont be hit-testable. Kinda thinking of doing like an association list and seeing about handling it on the CPU.
If you are only worried about file size, using glTF with morph targets and sparse accessors might be a good solution.