>For example if this is an multiplayer game you would have to synchronize the tree generation to look exactly the same for each player, and have the same collis

>For example if this is an multiplayer game you would have to synchronize the tree generation to look exactly the same for each player, and have the same collision box, or collision model (usually low-poly bounding convex or set of). This means you would have to communicate synchronize this with the clients. They just have to use identical seed values for their random number generators. Look at dwarf fortress: a few worldgen parameters and a single number are all you need to generate a fantasy world with complete with procedurally generated geography, population with traceable lineage, governments and other entities, and history, including artifacts and artwork that portray said history.