Best way to have a mesh dissolve from top to the bottom (world based) becoming particle effects?

Unity Engine
1

We’ve got a shader the clips the model top down in world space, and that works fine.

We also have a ray trace that runs rays into the mesh as the shader moves down giving us the points on the mesh to instantiate particle emitters.

The advantage to this is it allows us to have physics on and have the object dissolve away even as it is falling over. The disadvantage is the ray trace impacts CPU noticeably.

We have thought if freezing the model in place and calculating it’s vertex locations (from top to bottom in world) and instantiating the particle emitters at these locations. Advantage is it’s quick to do. The downside is we have to turn physics off (not ideal).

Is there a better way than these?

2

Why not just get the mesh location in world space? Or do the dissolve in object space, find points on the mesh, then transform the point using the model’s transform into world space (or game object space).