Regions, schematics and worlds

Regions

An area of the world with rules attached, indexed so asking what is at a location is cheap.

PluginRegions regions = Regions.of(this);
 
List<RegionSnapshot> here = Regions.at(player.getLocation());

The index is immutable and rebuilt on change rather than mutated, so a lookup never sees a half-written region and never needs a lock.

Regions.resolve(location, policy) is the one to reach for when two regions overlap and only one answer makes sense: the policy decides which wins rather than each caller inventing a rule.

The module also draws outlines — the particle box every arena editor uses — and handles selection with the shared wand.

Schematics

Saving a box of the world and pasting it back, over FastAsyncWorldEdit:

PluginSchematics schematics = Schematics.of(this);
 
schematics.save("arena_main", min, max);
schematics.regenerate("arena_main", cuboid, worldId);
schematics.paste("arena_main", location);
schematics.exists("arena_main");

It is what regenerates an arena between matches, with its chests still full. Every call is a future, and the work happens off the main thread.

Worlds

Creating and deleting worlds through the Worlds plugin, from any thread:

Worlds.create(Key.key("myplugin", "arena"), "arena_1")
      .thenAccept(world -> paste(world));
 
Worlds.delete(world);

Worlds.isAvailable() says whether anything can be created at all, and backendName() names what is doing it.

On Folia this is the only way: Bukkit's own world creation is not available there. Without the Worlds plugin the module does nothing loudly, and the caller finds out from the future rather than from an exception in the middle of a startup sequence.