Koncepciók

Tulajdonságok

Minden blokk egy alaptípus. Például alaptípusnak számít a föld, a lépcső és a levél. Viszont, hogy továbbá megkülönböztessük ezeket az alaptípusokat, minden blokknak van egy tulajdonság készlete, amelyből mindegyik vehet egy korlátozott mennyiségű értéket (pl. podzol föld, tégla lépcső, tölgyfa levél). Egy blokknak több tulajdonsága is lehet (mondjuk keletre-néző, tégla lépcső).

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:planks[variant=oak]
minecraft:planks[variant=spruce]
minecraft:planks[variant=birch]
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]

Some properties, however, are ephemeral – they exist only when the game is running. Their values are not written to the save file because their values can be detected automatically. For example, with Redstone wire, whether they are powered or not can be detected based on the environment (is there a lever that is on?). In this case, the power property of minecraft:redstone_wire as illustrated above is an ephemeral property.

As of writing, Minecraft still stores block data to an old format with 12 bits for a base type (4096 possible base types) and 4 bits for „metadata” (16 possible values per base type). However, properties do not map directly to metadata due to legacy reasons: for example, the furnace block consists of two base types (currently smelting versus not smelting), each not utilizing their metadata at all. On the other hand, logs do use their metadata fully, but because the combination of properties exceeds 16 possible values (think tree type and direction), logs must be split over two base types.

In the future, there will only be one 16 bit number (65536 possible combinations of base type + properties). Blocks will be assigned an ID automatically and this assignment will be stored in the world save file. This is illustrated below:

0 => minecraft:dirt[snowy=false,variant=default] 1 => minecraft:dirt[snowy=true,variant=default] 2 => minecraft:dirt[snowy=false,variant=grassless] 3 => minecraft:dirt[snowy=true,variant=grassless] 4 => minecraft:planks[variant=oak] 5 => minecraft:planks[variant=spruce] etc.

Blokkentitás adat

A lehetséges 65536 lehetséges kombinációval, nem lehet eltárolni annyi információt, mint mondjuk egy inventoryval, ezért van egy másik módja néhány blokknak az adattárolásra: blokkentitások.

Tile entities themselves are Java objects (like a Chest class). Normally, Minecraft code would access data in a tile entity by getting its instance and then calling it methods or fields, like a regular object (world.getTileEntity(position).getInventory()). When tile entities need to be written to the save file, they are stored in the NBT format.

Javaslat

Some things, like paintings, are actually entities.

However, tile entities can also override rendering so they don’t look like a regular block, although this is generally inefficient and causes a client framerate drop.