ZDoom

If you don't want to let your stuff splash because it causes too many splashes, give it the DONTSPLASH flag, that's what it is there for. Generally disabling it will cripple mods that use splashes and in particular their alerting properties.

Ah you beat me to posting so I reopened. See previous comment.

It actually doesn't involve D4D this time -- it doesn't even have a TERRAIN lump.

Some maps in particular, along with some mods such as AEons of Death, there can be a lot of terrain splashes which can slow down the game pretty heavily.

I personally don't like terrain splashes, yet I don't like having to rename/delete the TERRAIN lump and resetting the game just to make it kick into effect.

So in short, stops spawning of terrain actors/sounds.

I reckon many non-modders would also enjoy the ability to shut them off too since they don't know how to open the mods up.

I suspect that some stuff does not work properly with D4D, in which case it is time to fix the mod, not the engine.

As per usual, you did not elaborate on use case scenarios to try and convince anyone this would be useful in some way.

https://mantis.zdoom.org/view.php?id=634