Setting MobSpawner Attributes on an Item

MarkehMe · June 9, 2016, 7:00am

I’m dropping a Mob Spawner somewhat like so:

// ...

Optional<Entity> oItem = location.getExtent().createEntity(EntityTypes.ITEM, location.getPosition());

if (oItem.isPresent()) {
	Item item = (Item) oItem.get();
	item.offer(Keys.REPRESENTED_ITEM, ItemStack.of(ItemTypes.MOB_SPAWNER, 1).createSnapshot());

	location.getExtent().spawnEntity(item, cause);
}

// ...

This is working as is. However; how would I change the entities to spawn from this Mob Spawner? Can it be set to the Item?

pie_flavor · June 9, 2016, 7:07am

You must obtain a spawner BlockState, and then use Keys.ITEM_BLOCKSTATE.

MarkehMe · June 9, 2016, 7:32am

Doesn’t seem to change it. Using

item.offer(Keys.ITEM_BLOCKSTATE, block.getState());

Gained using

BlockSnapshot block = trans.getOriginal();

In a ChangeBlockEvent.Break event.

ZephireNZ · June 9, 2016, 8:14am

In fact, that is the wrong way to represent this. BlockState does not store the complex data that a spawner can - this data is contained within a BlockSnapshot. So you’ll want to build your snapshot, adding the data you want (eg Keys.SPAWNER_NEXT_ENTITY_TO_SPAWN for the EntityType) .

In writing this, I realise though… I can’t seem to find a data manipulator for representing a BlockSnapshot on an item… My guess it’s that it’s because BlockSnapshot inherently has a location in the world. I expect that it would be made a part of the upcoming schematic API which also includes “archetypes” for entities such as this.

@gabizou, am I correct?

ryantheleach · June 9, 2016, 8:33am

A block snapshot not currently placed in the world can still be a blocksnapshot.

github.com

SpongePowered/SpongeAPI/blob/74a6311b865e2ecc35e6e7851ccbc681e0119f97/src/main/java/org/spongepowered/api/data/LocateableSnapshot.java#L67


    Vector3i getPosition();
    /**
     * Gets the {@link Location} of the snapshot at which it may have been
     * taken from. The {@link Location} being immutable signifies that the
     * {@link LocateableSnapshot} can be re-created at the desired
     * {@link Location}.
     *
     * @return The location of where the snapshot was taken, if available
     */
    Optional<Location<World>> getLocation();
    /**
     * Creates a copy of the snapshot with the provided
     * {@link Location}.
     *
     * @param location The location
     * @return The new snapshot
     */
    T withLocation(Location<World> location);
}

means that the location might not be set.

MarkehMe · June 9, 2016, 9:10am

Was feeling really confident about this - got me excited for a moment!

However, just gave it a go…

Both:

block.get(Keys.SPAWNER_ENTITIES)

and

block.get(Keys.SPAWNER_NEXT_ENTITY_TO_SPAWN)

Were not present on the existing Mob Spawner (java.util.NoSuchElementException: No value present) using 1.8.9-4.2.0-BETA-336

Here was my use method:

	public Item alterItem(BlockSnapshot block, Item item) {
		if (item.getItemType() != ItemTypes.MOB_SPAWNER) return item;
		
		item.offer(Keys.SPAWNER_ENTITIES, block.get(Keys.SPAWNER_ENTITIES).get());
		item.offer(Keys.SPAWNER_NEXT_ENTITY_TO_SPAWN, block.get(Keys.SPAWNER_NEXT_ENTITY_TO_SPAWN).get());
		
		return item;
	}

ZephireNZ · June 9, 2016, 9:15am

Yep, the implementation of MobSpawnerData isn’t in Sponge yet anyway, I’m still waiting on it to be added here:

github.com/SpongePowered/Sponge

Implement MobSpawnerData

SpongePowered:bleeding ← ZephireNZ:data/mob-spawners

opened 11:30AM - 06 May 16 UTC

ZephireNZ

+1434 -405

[API](https://github.com/SpongePowered/SpongeAPI/pull/1226) | **Common** | [Forg…e](https://github.com/SpongePowered/SpongeForge/pull/794) This implements many of the missing parts to both `MobSpawnerData` and `Dungeon`. Dungeons now have two possible ways of generating a spawner: - `WeightedTable<EntityArchetype>` - When left as default, will use the vanilla/forge list of entity names and their weights - `MobSpawnerData` Both the builder and the `Dungeon` object itself have setters for these - setting one disables the other. Setting the choices to null, as mentioned in the java docs, will cause the `Dungeon` to use the vanilla list. Test code: ``` java @Plugin(id = "test-plugin", name = "Test Plugin", version = "1.0.0") public class TestPlugin { @Inject private Logger log; @Inject private PluginContainer container; @Listener public void onInit(LoadWorldEvent event) { event.getTargetWorld() .getWorldGenerator() .getPopulators(Dungeon.class) .stream() .map(Dungeon.class::cast) .filter(Objects::nonNull) .forEach(dungeon -> { WeightedTable<EntityArchetype> choices = new WeightedTable<>(); choices.add(EntityArchetype.of(EntityTypes.COW), 1); choices.add(EntityArchetype.of(EntityTypes.ENDERMAN), 1); dungeon.setChoices(choices); // MobSpawnerData data = new SpongeMobSpawnerData(); // Lazy, but meh // data.set(Keys.SPAWNER_NEXT_ENTITY_TO_SPAWN, new WeightedSerializableObject<>(EntityArchetype.of(EntityTypes.CHICKEN), 1)); // dungeon.setMobSpawnerData(data); }); } @Listener public void onGameStartedServer(GameStartedServerEvent event) { Sponge.getCommandManager().register(this, testKeysCommand(), "test-keys"); Sponge.getCommandManager().register(this, testDataCommand(), "test-data"); } private CommandCallable testKeysCommand() { return CommandSpec.builder() .executor((src, args) -> { Location<World> loc = getDefaultWorld().getLocation(0, 0, 0); if ((src instanceof Locatable)) { loc = ((Locatable) src).getLocation(); } // Create infront of location loc = loc.getBlockRelative(Direction.NORTH); loc.setBlock(BlockTypes.MOB_SPAWNER.getDefaultState(), Cause.of(NamedCause.source(container))); log.info("=== BEFORE ==="); dump(loc); loc.offer(Keys.SPAWNER_REMAINING_DELAY, (short) 1000); loc.offer(Keys.SPAWNER_MINIMUM_DELAY, (short) 200); loc.offer(Keys.SPAWNER_MAXIMUM_DELAY, (short) 1000); loc.offer(Keys.SPAWNER_SPAWN_COUNT, (short) 15); loc.offer(Keys.SPAWNER_MAXIMUM_NEARBY_ENTITIES, (short) 1); loc.offer(Keys.SPAWNER_REQUIRED_PLAYER_RANGE, (short) 50); loc.offer(Keys.SPAWNER_SPAWN_RANGE, (short) 3); loc.offer(Keys.SPAWNER_NEXT_ENTITY_TO_SPAWN, new WeightedSerializableObject<>(EntityArchetype.of(EntityTypes.SLIME), 1)); WeightedTable<EntityArchetype> table = new WeightedTable<>(); table.add(EntityArchetype.of(EntityTypes.BAT), 1); loc.offer(Keys.SPAWNER_ENTITIES, table); log.info("=== AFTER ==="); dump(loc); return CommandResult.success(); }) .build(); } private CommandCallable testDataCommand() { return CommandSpec.builder() .executor((src, args) -> { Location<World> loc = getDefaultWorld().getLocation(0, 0, 1); if ((src instanceof Locatable)) { loc = ((Locatable) src).getLocation(); } // Create infront of location loc = loc.getBlockRelative(Direction.NORTH); loc.setBlock(BlockTypes.MOB_SPAWNER.getDefaultState(), Cause.of(NamedCause.source(container))); MobSpawnerData data = loc.getOrCreate(MobSpawnerData.class).get(); log.info("=== BEFORE ==="); dump(data); data.set(Keys.SPAWNER_REMAINING_DELAY, (short) 1000); data.set(Keys.SPAWNER_MINIMUM_DELAY, (short) 200); data.set(Keys.SPAWNER_MAXIMUM_DELAY, (short) 1000); data.set(Keys.SPAWNER_SPAWN_COUNT, (short) 15); data.set(Keys.SPAWNER_MAXIMUM_NEARBY_ENTITIES, (short) 1); data.set(Keys.SPAWNER_REQUIRED_PLAYER_RANGE, (short) 50); data.set(Keys.SPAWNER_SPAWN_RANGE, (short) 3); data.set(Keys.SPAWNER_NEXT_ENTITY_TO_SPAWN, new WeightedSerializableObject<>(EntityArchetype.of(EntityTypes.SLIME), 1)); WeightedTable<EntityArchetype> table = new WeightedTable<>(); table.add(EntityArchetype.of(EntityTypes.BAT), 1); data.set(Keys.SPAWNER_ENTITIES, table); log.info("=== AFTER ==="); log.info("result {}", loc.offer(data).isSuccessful()); dump(loc.get(MobSpawnerData.class).get()); return CommandResult.success(); }) .build(); } private static World getDefaultWorld() { // Lazy, but meh return (World) SpongeImpl.getServer().getEntityWorld(); } private void dump(ValueContainer<?> data) { log.info("remaining {}", data.get(Keys.SPAWNER_REMAINING_DELAY).get()); log.info("min {}", data.get(Keys.SPAWNER_MINIMUM_DELAY).get()); log.info("max {}", data.get(Keys.SPAWNER_MAXIMUM_DELAY).get()); log.info("count {}", data.get(Keys.SPAWNER_SPAWN_COUNT).get()); log.info("nearby {}", data.get(Keys.SPAWNER_MAXIMUM_NEARBY_ENTITIES).get()); log.info("playerrange {}", data.get(Keys.SPAWNER_REQUIRED_PLAYER_RANGE).get()); log.info("range {}", data.get(Keys.SPAWNER_SPAWN_RANGE).get()); log.info("next {}", data.get(Keys.SPAWNER_NEXT_ENTITY_TO_SPAWN).get().toContainer().toString()); log.info("possible [{}]", Joiner.on(", ").join(data.get(Keys.SPAWNER_ENTITIES).get())); } } ```

So basically at the moment you’re down on two counts…

MarkehMe · June 9, 2016, 9:17am

Oh my… life goes on !

I will keep the code commented out for Mob Spawners until that is implemented. If there is anything I can do to assist, let me know. I’ll be sure to subscribe to that thread on GitHub.

gabizou · June 9, 2016, 7:16pm

You’re partially correct, the point of the MobSpawnerData is to change the tile entity information without having to rely on going from one DataHolder to an ImmutableDataHolder and then finally reaching the point where you can interact with data.