Conceptos
Propiedades
All blocks are of a base type. Examples of base types include redstone dust, brick stairs, and chest. However, to further differentiate these base types, each block has set of different properties, of which each can take a limited set of values (i.e. activated redstone, corner brick stairs, double chest). A block can have multiple properties (such as corner,*upsidedown* stairs).
Examples of block properties
minecraft:dirt[snowy=false,variant=default] minecraft:dirt[snowy=true,variant=default] minecraft:dirt[snowy=false,variant=grassless] minecraft:dirt[snowy=true,variant=grassless] minecraft:redstone_wire[east=up,north=up,power=0,south=up,west=up] minecraft:redstone_wire[east=side,north=up,power=0,south=up,west=up] minecraft:redstone_wire[east=none,north=up,power=0,south=up,west=up] minecraft:redstone_wire[east=up,north=side,power=0,south=up,west=up]
Algunas propiedades, sin embargo, son efímeras – estas existen sólo cuando el juego se ejecuta. Sus valores no estan escritos en el archivo save porque sus valores pueden ser detectados automáticamente. Por ejemplo, con el circuito de Redstone, que aunque estén en funcionamiento o no pueden ser detectados en base al ambiente (¿alguna palanca está encendida?). En este caso, la propiedad «power» de «minecraft:redstone_wire» como se muestra arriba es una propiedad efímera.
Each property will have a finite number of valid values that can be assigned to the property. Exampeles would be that redstone power can only be a value between 0 and 15. This means that Minecraft knows each possible state of a block prior to fully booting the server. This is required knowledge as sending blocks over the network are compressed to a number.
Block Entity Data
With block properties having a known preset of possible values, these cannot be used when attempting to store data whereby there is a infinite amount of possibilities. Examples include sign text and block inventories.
Minecraft’s solution to this is block entities, which are Java objects that store additional data on a Location the block is at in NBT format. Examples of block entities are Chest
Example use would be to receive the inventory of a chest. This can be done as follows
import org.spongepowered.api.world.server.ServerLocation;
import org.spongepowered.api.block.entity.BlockEntity;
import org.spongepowered.api.block.entity.carrier.chest.Chest;
import org.spongepowered.api.item.inventory.type.BlockEntityInventory;
public Optional<BlockEntityInventory<Chest>> getChestInventory(ServerLocation location){
Optional<BlockEntity> optionalBlockEntity = location.blockEntity();
if(optionalBlockEntity.isPresent()){
BlockEntity blockEntity = optionalBlockEntity.get();
if(blockEntity instanceof Chest){
Chest chest = (Chest) blockEntity;
return Optional.of(chest.inventory());
}
}
return Optional.empty();
}
Truco
Algunas cosas, como pinturas, son en realidad entidades.
Sin embargo, las entidades también pueden suplantar a la prestación para que no parezca un bloque regular, aunque esto es generalmente ineficiente y provoca una caída de framerate cliente.