@Rodidon : If you play Need For Speed etc .. i think it's textue not 3D ! Some othesr uses 3D tiles or a tool that allow to "gleu" any type of pluggable 3D tiles road made to be "glued" together ! or you could use Texture projection on top of 3D road also. But if you plan polygons and the engine handles all that, go for it !
@Redeemer: My photo is included in 3D coat by default Just kidding, it's photo from the author of 3D Coat !