How do holo decks on Star Trek work?

The hoodie I uses a combination photons and forcefields for the environment while objects and anything you touch uses replicator technology similar to the transporter. As to the toilet, since you're sitting on it, it's replicated so you poop in a toilet. The fecal matter would probably be broken down with the toilet itself and sent to the ship's waste recycling facilities.

The holodeck creates "solid holograms." Nothing you see in the holodeck is a real object, or person. It's just a projection.

So while you could touch a plate of food, and even pick up an item of food, it's just a projection - there's nothing really there.

Now I suppose you could combine a holodeck and a replicator so you could create real food within the holodeck, and maybe even other simple objects.

As for using the toilet, this is Star Trek. No one ever uses the bathroom in Star Trek. Even the official blueprints for the Enterprise are all strangely lacking in...toilets.

The more you think about it, the less sense it makes. But I think food on the holodeck is replicated.