What are compounds used for?

[daortir]

Basically it allows you to rotate a group of items with efficiency. Exemple : I have a level in my mod where the whole mansion is tilted. In order to do it successfully, I selected everything, made it a compound, then rotated it slightly. It lagged incredibly hard, but I had the whole mansion tilted.

If you do this without a compound, you'll get very weird results as every item will rotate where it stands, leading to something that is completely incoherent.

Ah, it's hard to explain as my english isn't the best, just select a bookshelf and the books in it, and rotate it.
It'll mess up. Now make it a compound, and tadaaaa you can rotate everything at once and the books will stay in place.