Map Material Through Vehicle Floor

i have found that water, sand, grass and mud go through the floor of the car.

See pics below

 

Same goes for any game.

It's pretty impossible to overcome, especially the water and mud.

 

Except it can be overcome. You could set a mesh within the cars interior, which is entirely transparent, and when the mesh/material of an insignificant map object enters it, it cannot be seen, yet the floor of the car and such still can. I know this can be done through materials.

 

what?

How is that supposed to work, Stormdrain?

There is a way using the stencil buffer though.