Doom3world

Is there a way to program the game to hide a model if the player can't see it? Meaning, if any model is behind a wall then it won't be rendered?

I'm guessing this would need two things: A function that does a type of a trace from the player to every entity each frame, and some type of hide command that pulls the entity's model. I don't know if the second item is possible from editing just the game's code, is it?

The engine already does that for you, to an extent.
If the wall is visportaled, any entity will be hidden.

I know. But I'm looking for a solution to "outdoor area" performance issues where visportals aren't possible.