As a Roblox developer it is nearly impossible to partially limit rendering of certain parts. The only way to do something similar right now is to use Glass material bugs, but it will be fixed sooner or later, and isn’t performance friendly.
I’d like Roblox to add some mask property to parts which we could link to multiple objects that appear in the 3D viewport (whether it would be parts, terrain, particle emitters etc.).
It would partially work like the Glass material bug currently does - it would “block” anything behind it’s surface:
I believe it should have a sub-property that would control wheter it blocks everything of the linked part(s) behind it or just the area of it’s intersection:
How “linking” or “whitelisting/blacklisting” objects could work:
Or perhaps it could work similarly to Collision Groups, where we could set which groups should interact with each other
Few use cases I can think of right now are fixing holograms or glass panels (I think it would work great with Lumber Tycoon 2’s glass panels @Defaultio), blocking rain from inside of buildings, blocking water from boats and many more:
All of the body parts are linked with each other/in the same “group”
Glass pieces are linked to each other
The invisible, boat-shaped "no-render part is linked to Terrain
@WoodReviewer, please don’t kill me, this is just for illustration
The invisible, building-shaped mask part is linked to a Particle Emitter
The top right sphere is linked to the top left sphere, but not to the spheres on the bottom.
If Roblox was to add this feature, it would allow for many special effects to further increase game immersion.