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Ta strona jest o the latest official PC version of Minecraft. Dla the 2013 April Fools' day "Minecraft 2.0" version zobacz Minecraft 2.0/Chunk format.

Chunks store the terrain and entities within a 16×256×16 area. They also store precomputed lighting, heightmap data for Minecraft's performance, and other meta information.

NBT structure

Chunks are stored in NBT format, with this structure (see Block Format below for the ordering of the blocks within each array):

• The root tag.
  •  DataVersion: Version of the chunk NBT structure.
  •  Level: Chunk data.
    •  xPos: X position of the chunk.
    •  zPos: Z position of the chunk.
    •  LastUpdate: Tick when the chunk was last saved.
    •  LightPopulated: 1 or 0 (true/false) - If true, the server/client has already calculated lighting values for this chunk after generation.
    •  TerrainPopulated: 1 or not present (true/false) indicate whether the terrain in this chunk was populated with special things. (Ores, special blocks, trees, dungeons, flowers, waterfalls, etc.) If set to zero then Minecraft will regenerate these features in the blocks that already exist.
    •  V: Currently always saved as 1 and not actually loaded by the game. Likely a chunk version tag.
    •  InhabitedTime: The cumulative number of ticks players have been in this chunk. Note that this value increases faster when more players are in the chunk. Used for regional difficulty: increases the chances of mobs spawning with equipment, the chances of that equipment having enchantments, the chances of spiders having potion effects, the chances of mobs having the ability to pick up dropped items, and the chances of zombies having the ability to spawn other zombies when attacked. Note that at values 3600000 and above, regional difficulty is effectively maxed for this chunk. At values 0 and below, the difficulty is capped to a minimum (thus, if this is set to a negative number, it will behave identically to being set to 0, apart from taking time to build back up to the positives). See Regional Difficulty for more specifics.
    •  Biomes: May not exist. 256 bytes of biome data, one byte for each vertical column in the chunk. See Data Values for biome IDs. If this tag does not exist it will be created and filled by Minecraft when the chunk is loaded and saved. If any values in this array are -1, Minecraft will also set them to the correct biome.
    •  HeightMap: 1024 bytes(256 TAG_Int) of heightmap data. 16 × 16. Each byte records the lowest level in each column where the light from the sky is at full strength. Speeds computing of the SkyLight.
    •  Sections: List of Compound tags, each tag is a sub-chunk of sorts.
      • An individual Section.
        •  Y: The Y index (not coordinate) of this section. Range 0 to 15 (bottom to top), with no duplicates but some sections may be missing if empty.
        •  Blocks: 4096 bytes of block IDs defining the terrain. 8 bits per block, plus the bits from the below Add tag.
        •  Add: May not exist. 2048 bytes of additional block ID data. The value to add to (combine with) the above block ID to form the true block ID in the range 0 to 4095. 4 bits per block. Combining is done by shifting this value to the left 8 bits and then adding it to the block ID from above.
        •  Data: 2048 bytes of block data additionally defining parts of the terrain. 4 bits per block.
        •  BlockLight: 2048 bytes recording the amount of block-emitted light in each block. Makes load times faster compared to recomputing at load time. 4 bits per block.
        •  SkyLight: 2048 bytes recording the amount of sunlight or moonlight hitting each block. 4 bits per block.
    •  Entities: Each TAG_Compound in this list defines an entity in the chunk. See Entity Format below. If this list is empty it will be a list of Byte tags.
    •  TileEntities: Each TAG_Compound in this list defines a block entity in the chunk. See Block Entity Format below. If this list is empty it will be a list of Byte tags.
    •  TileTicks: May not exist. Each TAG_Compound in this list is an "active" block in this chunk waiting to be updated. These are used to save the state of redstone machines, falling sand or water, and other activity. See Tile Tick Format below. This tag may not exist.

Block format

In the Anvil format, block positions are ordered YZX for compression purposes.

The coordinate system is as follows:

• X increases East, decreases West
• Y increases upwards, decreases downwards
• Z increases South, decreases North

This also happens to yield the most natural scan direction, because all indices in the least significant dimension (i.e. X in this case) appear for each index in the next most significant dimension; so one reads an array ordered YZX as one would a book lying with its top northward, all letters (or X-indices) on a single line (or Z-index) at a time, and all lines on a single page (or Y-index) at a time. For the 2D arrays (i.e. "Biomes" and "HeightMap") the inapplicable Y dimension is simply omitted, as though the book is only one page thick.

Each section in a chunk is a 16x16x16-block area, with up to 16 sections in a chunk. Section 0 is the bottom section of the chunk, and section 15 is the top section of the chunk. To save space, completely empty sections are not saved. Within each section is a byte tag "Y" for the Y index of the section, 0 to 15, and then byte arrays for the blocks. The "Block" byte array has 4096 partial block IDs at 8 bits per block. Another byte array "Add" is used for block with IDs over 255, and is 2048 bytes of the other part of the 4096 block IDs at 4 bits per block. When both the "Block" and "Add" byte arrays exist, the partial ID from the "Add" array is shifted left 8 bits and added to the partial ID from the "Blocks" array to form the true Block ID. The "Data" byte array is also 2048 bytes for 4096 block data values at 4 bits per block. The "BlockLight" and "SkyLight" byte arrays are the same as the "Data" byte array but they are used for block light levels and sky light levels respectively. The "SkyLight" values represent how much sunlight or moonlight can potentially reach the block, independent of the current light level of the sky.

The endianness of the 2048-byte arrays (i.e. "Add," "Data," "BlockLight," & "SkyLight"), which give only 4 bits per block, seems to stand as the one anomalous exception to the otherwise consistent, format-wide standard of big-endian data storage. It also runs counter to the presumably natural human-readable printing direction. If the blocks begin at 0, they are grouped with even numbers preceding odd numbers (i.e. 0 & 1 share a byte, 2 & 3 share the next, etc.); under these designations Minecraft stores even-numbered blocks in the least significant half-byte, and odd-numbered blocks in the most significant half-byte. Thus block[0] is byte[0] at 0x0F, block[1] is byte[0] at 0xF0, block[2] is byte[1] at 0x0F, block[3] is byte[1] at 0xF0, etc. ...

The pseudo-code below shows how to access individual block information from a single section. Hover over text to see additional information or comments.

byte Nibble4(byte[] arr, int index){ return index%2 == 0 ? arr[index/2]&0x0F : (arr[index/2]>>4)&0x0F; }
int BlockPos = y*16*16 + z*16 + x;
byte BlockID_a = Blocks[BlockPos];
byte BlockID_b = Nibble4(Add, BlockPos);
short BlockID = BlockID_a + (BlockID_b << 8);
byte BlockData = Nibble4(Data, BlockPos);
byte Blocklight = Nibble4(BlockLight, BlockPos);
byte Skylight = Nibble4(SkyLight, BlockPos);

Entity format

Every entity is an unnamed  TAG_Compound contained in the Entities list of a chunk file. The sole exception is the Player entity, stored in level.dat, or in <player>.dat files on servers. All entities share this base:

id Pos Motion Rotation FallDistance Fire Air OnGround Dimension Invulnerable PortalCooldown UUIDMost UUIDLeast UUID CustomName CustomNameVisible Silent Riding CommandStats SuccessCountObjective SuccessCountName AffectedBlocksObjective AffectedBlocksName AffectedEntitiesObjective AffectedEntitiesName AffectedItemsObjective AffectedItemsName QueryResultObjective QueryResultName

• Entity data

Chunk format/Entity

Mobs

Mob Entities
Entity ID	Name
Bat	Bat
Blaze	Blaze
CaveSpider	Cave Spider
Chicken	Chicken
Cow	Cow
Creeper	Creeper
EnderDragon	Ender Dragon
Enderman	Enderman
Endermite	Endermite
Ghast	Ghast
Giant	Giant
Guardian	Guardian Elder Guardian
EntityHorse	Horse
LavaSlime	Magma Cube
MushroomCow	Mooshroom
Ozelot	Ocelot
Pig	Pig
PigZombie	Zombie Pigman
Rabbit	Rabbit
Sheep	Sheep
Shulker	Shulker
Silverfish	Silverfish
Skeleton	Skeleton Wither Skeleton
Slime	Slime
SnowMan	Snow Golem
Spider	Spider
Squid	Squid
Villager	Villager
VillagerGolem	Iron Golem
Witch	Witch
WitherBoss	Wither
Wolf	Wolf
Zombie	Zombie Zombie Villager

Mobs are a subclass of Entity with additional tags to store their health, attacking/damaged state, potion effects, and more depending on the mob. Players are a subclass of Mob.

Projectiles

Projectile Entities
Entity ID	Name
Arrow	Arrow
DragonFireball	Ender Dragon Fireball
Fireball	Ghast Fireball
SmallFireball	Blaze Fireball/Fire Charge
Snowball	Snowball
SpectralArrow	Spectral Arrow
ThrownEgg	Egg
ThrownEnderpearl	Ender Pearl
ThrownExpBottle	Bottle o' Enchanting
ThrownPotion	Splash Potion
WitherSkull	Wither Skull

Projectiles are a subclass of Entity and have very obscure tags such as X,Y,Z coordinate tags despite Entity Pos tag, inTile despite inGround, and shake despite most projectiles not being arrows. While all projectiles share tags, they are all independently implemented through Throwable, ArrowBase, and FireballBase.

Items and XPOrbs

Item Entities
Entity ID	Name
Item	Dropped Item
XPOrb	Experience Orb

Items and XPOrbs are a subclass of Entity. Szablon:Data transclude Szablon:Data transclude

Vehicles

Vehicle Entities
Entity ID	Name
Boat	Boat
Minecart (deprecated)	Minecart Minecart with Chest Minecart with Furnace
MinecartRideable	Minecart
MinecartChest	Minecart with Chest
MinecartFurnace	Minecart with Furnace
MinecartSpawner	Minecart with Spawner
MinecartTNT	Minecart with TNT
MinecartHopper	Minecart with Hopper
MinecartCommandBlock	Minecart with Command Block

Vehicles are subclasses of Entity.

Dynamic tiles

Dynamic Block Entities
Entity ID	Name
PrimedTnt	TNT
FallingSand	Dynamic Tile

Dynamic tiles are a subclass of Entity and are used to simulate realistically moving blocks.

Other

Other Entities
Entity ID	Name
AreaEffectCloud	Area Effect Cloud
ArmorStand	Armor Stand
EnderCrystal	Ender Crystal
EyeOfEnderSignal	Eye of Ender
FireworksRocketEntity	Firework Rocket
ItemFrame	Item Frame
LeashKnot	Lead Knot
Painting	Painting
ShulkerBullet	Shulker Bullet
	Fishing Rod Bobber

Other entity types that are a subclass of Entity but do not fit into any of the above categories.

Block entity format

Block Entities
Block Entity ID	Associated Block
Airportal	End Portal (block)
Banner	Banner
Beacon	Beacon
Cauldron	Brewing Stand
Chest	Chest Trapped Chest
Comparator	Redstone Comparator
Control	Command Block
DLDetector	Daylight Sensor
Dropper	Dropper
EnchantTable	Enchantment Table
EnderChest	Ender Chest
EndGateway	End Gateway (block)
FlowerPot	Flower Pot
Furnace	Furnace
Hopper	Hopper
MobSpawner	Monster Spawner
Music	Note Block
Piston	Piston Moving
RecordPlayer	Jukebox
Sign	Sign
Skull	Mob head
Trap	Dispenser

A block entity (not related to entity) is used by Minecraft to store information about a block that can't be stored in the four bits of block data the block has. Block entities were called "tile entities" until the 1.8 snapshots and that term is still used in some command usage.

Tile tick format

Tile Ticks represent block updates that need to happen because they could not happen before the chunk was saved. Examples reasons for tile ticks include redstone circuits needing to continue updating, water and lava that should continue flowing, recently placed sand or gravel that should fall, etc. Tile ticks are not used for purposes such as leaf decay, where the decay information is stored in the leaf block data values and handled by Minecraft when the chunk loads. For map makers, tile ticks can be used to update blocks after a period of time has passed with the chunk loaded into memory.

• A Tile Tick
  •  i: The ID of the block; used to activate the correct block update procedure.
  •  t: The number of ticks until processing should occur. May be negative when processing is overdue.
  •  p: If multiple tile ticks are scheduled for the same tick, tile ticks with lower p will be processed first. If they also have the same p, the order is unknown.
  •  x: X position
  •  y: Y position
  •  z: Z position

History

Chunks were first introduced in Minecraft Infdev. Before the addition of the MCRegion format in Beta 1.3, chunks were stored as individual chunk files ".dat" where the file names contained the chunk's position encoded in Base36 - this is known as the Alpha level format. MCRegion changed this by storing groups of 32×32 chunks in individual ".mcr" files with the coordinates in Base10, with the goal being to reduce disk usage by cutting down on the number of file handles Minecraft had open at once. MCRegion's successor is the current format, Anvil, which only made changes to the chunk format. The region file technique is still used, but the region file extensions are ".mca" instead.

The major change from MCRegion to Anvil was the division of Chunks into Sections; each chunk has up to 16 individual 16×16×16 block Sections so that completely empty sections will not be saved at all. Preparation has also been made to support blocks with IDs in the range 0 to 4095, as compared to the previous 0 to 255 limitation. However, Minecraft is not fully prepared for such blocks to exist as items; many item IDs are already taken in the range 256 to 4095.

The Blocks, Data, BlockLight, and SkyLight arrays are now housed in individual chunk Sections. The Data, SkyLight, and BlockLight are arrays of 4-bit values, and the BlockLight and SkyLight arrays no longer house part of the block ID. The Blocks array is 8 bits per block, and the 4096-blocks support exists in the form of an optional Add byte array of 4-bits per block for additional block ID information. With the Anvil format, the NBT Format was changed from Notch's original specification to include an integer array tag similar to the existing byte array tag. It is currently only used for HeightMap information in chunks.

Pełna wersja
?					Removed MaxExperience, RemainingExperience, ExperienceRegenTick, ExperienceRegenRate and ExperienceRegenAmount from MobSpawner.
1.4.2			12w34a		Added entity WitherBoss.
1.5			13w02a		Added entity MinecartTNT.
					Minecart is now deprecated.
			13w03a		Added entity MinecartHopper.
			13w06a		Added entity MinecartSpawner.
1.6.1			13w16a		Added entity EntityHorse.
			13w21a		Removed ArmorType from EntityHorse.
					Removed Saddle from EntityHorse.
			1.6.1-pre		Readded Saddle to EntityHorse.
1.7.2			13w39a		Added entity MinecartCommandBlock.
1.8			14w02a		Added Lock to containers.
					Item IDs are no longer used when specifying NBT data.
					Added Block to FallingSand, using the alphabetical ID format.
			14w06a		Added ShowParticles to all mobs.
					Added PickupDelay to item entities.
					Setting Age to -32768 makes items which never expire.
					Removed AttackTime from mobs.
			14w10a		Added rewardExp to Villager.
					Added OwnerUUID for mobs that can breed.
					Added Owner to Skull.
					Changes to item frames and paintings: added Facing, TileX, TileY and TileZ now represent the co-ordinates of the block the item is in rather than what it is placed on, deprecated Direction and Dir.
			14w11a		Added entity Endermite.
					Added EndermiteCount to Enderman.
			14w21a		CustomName and CustomNameVisible now work for all entities.
			14w25a		Added entity Guardian.
					Added Text1, Text2, Text3 and Text4 to signs. The limit no longer depends on the amount of characters (16), it now depends on the width of the characters.
			14w27a		Added entity Rabbit. Added CommandStats to command blocks and signs.
			14w28a		Removed EndermiteCount from Enderman.
			14w30a		Added Silent for all entities.
			14w32a		Added NoAI for all mobs.
					Added entity ArmorStand.
			14w32c		Added NoBasePlate to ArmorStand.
1.9			15w31a		Added tags HandItems, ArmorItems, HandDropChances, and ArmorDropChances to Living, which replace the DropChances and Equipment tags.
					Added HandItems and ArmorItems to ArmorStand.
					Added Glowing to Entity.
					Added Team to LivingBase.
					Added DragonPhase to EnderDragon
					Added entity Shulker, child of SnowMan.
					Added entity ShulkerBullet, child of Entity.
					Added entity DragonFireball, which extends FireballBase and has no unique tags.
					Added entities TippedArrow and SpectralArrow, children of Arrow.
					Added block EndGateway, child of TileEntity.
			15w32a		Tags and DataVersion tag can now be applied on entities.
					Changed the Fuse tag's type for the PrimedTnt entity from "Byte" to "Short".
			15w32c		Introduced a limit on the amount of tags an entity can have (1024 tags). When surpassed it displays an error saying: "Cannot add more than 1024 tags to an entity."
			15w33a		Added entity AreaEffectCloud, child of Entity.
					Added ExactTeleport and renamed Life to Age for EndGateway.
					Added Linger to ThrownPotion.
					Removed DataVersion from Entity. It is now only applied to Player only, child of LivingBase.
					Removed UUID from Entity.
					HealF under LivingBase has become deprecated.
					Health under LivingBase has changed from type "Short" to "Float".
					Equipment removed from ArmorStand and Living entity, its usage replaced by HandItems and ArmorItems which were added earlier.
			15w33c		Added BeamTarget to EnderCrystal.
			15w34a		Added powered and conditional byte tags to Control tile entity for command blocks.
					Added life and power to FireballBase.
					Added id inside SpawnData to MobSpawner.
					Added powered to the Music tile entity for note blocks.
			15w35a		Added VillagerProfession to Zombie.
			15w37a		Added Enabled to MinecartHopper.
			15w38a		Added SkeletonTrap and SkeletonTrapTime to EntityHorse.
			15w41a		Replaced Riding with Passengers for all entities.
					Added RootVehicle for all passengers.
					Added Type to Boat.
			15w42a		Added Fuel to Cauldron (brewing stands).
			15w43a		Added LootTable and LootTableSeed to Chest, Minecart and MinecartHopper.
					Added DeathLootTable and DeathLootTableSeed to all mobs.
					Added life and power to all fireballs (FireballBase).
			15w44a		Added ShowBottom to EnderCrystal.
			15w44b		Added Potion and CustomPotionEffects to Arrow.
					Added Potion to AreaEffectCloud.
			15w45a		Removed Linger from ThrownPotion. Instead, the potion will linger if the stored item has an ID of minecraft:lingering_potion.
					ThrownPotion will now render as its stored item even if the item is not a potion.
			15w46a		MoreCarrotTicks from Rabbit is now set to 40 when rabbits eat a carrot crop, but is not used anyway.
			15w47a		Added PaymentItem to Beacon.
			15w49a		Removed PaymentItem from Beacon.
					In order for a sign to accept text, all 4 tags ("Text1", "Text2", "Text3", and "Text4") must exist.
			15w51b		The original values of DisabledSlots in ArmorStand have changed in nature.