Konsepter
Egenskaper
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]
Noen egenskaper er derimot flyktige – de eksisterer kun når spillet kjører. Deres verdier skrives ikke til lagringsfilen fordi verdiene kan oppdages automatisk. For eksempel, med redstoneledninger, kan man merke om de er påslått eller ikke basert på området rundt (finnes det en påslått spak?). I dette tilfellet er power-egenskapen til minecraft:redstone_wire, som vist over, en flyktig egenskap.
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();
}
Tips
Noen ting, som malerier, er faktisk entiteter.
Tile entities kan imidlertid også overstyre rendering slik at de ikke ser ut som en vanlig blokk, selv om dette generelt sett er ineffektivt og medfører et tap i bildefrekvensen på klienter.
