Difference between revisions of "Pre-release protocol"
Nickelpro1 (talk | contribs) (Undo revision 15989 by Nickelpro1 (talk)) Tag: Undo |
(→Chunk Data: Illustration of what it looks like now, based on my understanding (may be wrong!)) |
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{{Change||The compacted array format has been adjusted so that individual entries no longer span across multiple longs, affecting the main data array and heightmaps.}} | {{Change||The compacted array format has been adjusted so that individual entries no longer span across multiple longs, affecting the main data array and heightmaps.}} | ||
+ | |||
+ | New format, 5 bits per block, containing the following references to blocks in a palette (not shown): <span style="border: solid 2px hsl(0, 90%, 60%)">1</span><span style="border: solid 2px hsl(30, 90%, 60%)">2</span><span style="border: solid 2px hsl(60, 90%, 60%)">2</span><span style="border: solid 2px hsl(90, 90%, 60%)">3</span><span style="border: solid 2px hsl(120, 90%, 60%)">4</span><span style="border: solid 2px hsl(150, 90%, 60%)">4</span><span style="border: solid 2px hsl(180, 90%, 60%)">5</span><span style="border: solid 2px hsl(210, 90%, 60%)">6</span><span style="border: solid 2px hsl(240, 90%, 60%)">6</span><span style="border: solid 2px hsl(270, 90%, 60%)">4</span><span style="border: solid 2px hsl(300, 90%, 60%)">8</span><span style="border: solid 2px hsl(330, 90%, 60%)">0</span><span style="border: solid 2px hsl(0, 90%, 30%)">7</span><span style="border: solid 2px hsl(30, 90%, 30%)">4</span><span style="border: solid 2px hsl(60, 90%, 30%)">3</span><span style="border: solid 2px hsl(90, 90%, 30%)">13</span><span style="border: solid 2px hsl(120, 90%, 30%)">15</span><span style="border: solid 2px hsl(150, 90%, 30%)">16</span><span style="border: solid 2px hsl(180, 90%, 30%)">9</span><span style="border: solid 2px hsl(210, 90%, 30%)">14</span><span style="border: solid 2px hsl(240, 90%, 30%)">10</span><span style="border: solid 2px hsl(270, 90%, 30%)">12</span><span style="border: solid 2px hsl(300, 90%, 30%)">0</span><span style="border: solid 2px hsl(330, 90%, 30%)">2</span> | ||
+ | |||
+ | <code>0020863148418841</code> <code><span style="outline: dashed 2px black">0000</span><span style="outline: solid 2px hsl(330, 90%, 60%)">00000</span><span style="outline: solid 2px hsl(300, 90%, 60%)">01000</span><span style="outline: solid 2px hsl(270, 90%, 60%)">00100</span><span style="outline: solid 2px hsl(240, 90%, 60%)">00110</span><span style="outline: solid 2px hsl(210, 90%, 60%)">00110</span><span style="outline: solid 2px hsl(180, 90%, 60%)">00101</span><span style="outline: solid 2px hsl(150, 90%, 60%)">00100</span><span style="outline: solid 2px hsl(120, 90%, 60%)">00100</span><span style="outline: solid 2px hsl(90, 90%, 60%)">00011</span><span style="outline: solid 2px hsl(60, 90%, 60%)">00010</span><span style="outline: solid 2px hsl(30, 90%, 60%)">00010</span><span style="outline: solid 2px hsl(0, 90%, 60%)">00001</span></code><br> | ||
+ | <code>01018A7260F68C87</code> <code><span style="outline: dashed 2px black">0000</span><span style="outline: solid 2px hsl(330, 90%, 30%)">00010</span><span style="outline: solid 2px hsl(300, 90%, 30%)">00000</span><span style="outline: solid 2px hsl(270, 90%, 30%)">01100</span><span style="outline: solid 2px hsl(240, 90%, 30%)">01010</span><span style="outline: solid 2px hsl(210, 90%, 30%)">01110</span><span style="outline: solid 2px hsl(180, 90%, 30%)">01001</span><span style="outline: solid 2px hsl(150, 90%, 30%)">10000</span><span style="outline: solid 2px hsl(120, 90%, 30%)">01111</span><span style="outline: solid 2px hsl(90, 90%, 30%)">01101</span><span style="outline: solid 2px hsl(60, 90%, 30%)">00011</span><span style="outline: solid 2px hsl(30, 90%, 30%)">00100</span><span style="outline: solid 2px hsl(0, 90%, 30%)">00111</span></code> | ||
==== Update Light ==== | ==== Update Light ==== |
Revision as of 19:39, 30 August 2020
This page documents the changes from the last stable Minecraft release (currently 1.15.2, protocol 578) to the current pre-release (currently 1.16.2, protocol 751). Note that this page contains bleeding-edge information that may not be completely or correctly documented.
One who wishes to commandeer the merging of this into Protocol when an update is made must be sure to respect any changes that may have occurred to the respective packets there.
Contents
Data types
The UUID type is now also sometimes encoded by the Notchian server as an array of four 32-bit integers, from most significant to least significant (matching the new format used on entity NBT). This representation is identical to using 16 bytes, two 64-bit integers, or one 128-bit integers.
Packets
ID | Packet name | Documentation | |
---|---|---|---|
Handshaking serverbound | |||
0x00 | Handshake | Current | Pre |
Play clientbound | |||
0x02 | Spawn Weather Entity | Current | |
Spawn Living Entity | Current | (unchanged) | |
Spawn Painting | Current | (unchanged) | |
Spawn Player | Current | (unchanged) | |
Entity Animation (clientbound) | Current | (unchanged) | |
Statistics | Current | (unchanged) | |
Acknowledge Player Digging | Current | (unchanged) | |
Block Break Animation | Current | (unchanged) | |
Block Entity Data | Current | (unchanged) | |
Block Action | Current | (unchanged) | |
Block Change | Current | (unchanged) | |
Boss Bar | Current | (unchanged) | |
Server Difficulty | Current | (unchanged) | |
Chat Message (clientbound) | Current | Pre | |
Tab-Complete (clientbound) | Current | (unchanged) | |
Declare Commands | Current | (unchanged) | |
Window Confirmation (clientbound) | Current | (unchanged) | |
Close Window (clientbound) | Current | (unchanged) | |
Window Items | Current | (unchanged) | |
Window Property | Current | (unchanged) | |
Set Slot | Current | (unchanged) | |
Set Cooldown | Current | (unchanged) | |
Plugin Message (clientbound) | Current | (unchanged) | |
Named Sound Effect | Current | (unchanged) | |
Disconnect (play) | Current | (unchanged) | |
Entity Status | Current | (unchanged) | |
Explosion | Current | (unchanged) | |
Unload Chunk | Current | (unchanged) | |
Change Game State | Current | (unchanged) | |
Open Horse Window | Current | (unchanged) | |
Keep Alive (clientbound) | Current | (unchanged) | |
Chunk Data | Current | Pre | |
Effect | Current | (unchanged) | |
Particle | Current | (unchanged) | |
Update Light | Current | Pre | |
Join Game | Current | Pre | |
Map Data | Current | (unchanged) | |
Trade List | Current | (unchanged) | |
Entity Position | Current | (unchanged) | |
Entity Position and Rotation | Current | (unchanged) | |
Entity Rotation | Current | (unchanged) | |
Entity Movement | Current | (unchanged) | |
Vehicle Move (clientbound) | Current | (unchanged) | |
Open Book | Current | (unchanged) | |
Open Window | Current | (unchanged) | |
Open Sign Editor | Current | (unchanged) | |
Craft Recipe Response | Current | (unchanged) | |
Player Abilities (clientbound) | Current | (unchanged) | |
Combat Event | Current | (unchanged) | |
Player Info | Current | (unchanged) | |
Face Player | Current | (unchanged) | |
Player Position And Look (clientbound) | Current | (unchanged) | |
Unlock Recipes | Current | Pre | |
Destroy Entities | Current | (unchanged) | |
Remove Entity Effect | Current | (unchanged) | |
Resource Pack Send | Current | (unchanged) | |
Respawn | Current | Pre | |
Entity Head Look | Current | (unchanged) | |
Multi Block Change | Current | Pre | |
Select Advancement Tab | Current | (unchanged) | |
World Border | Current | (unchanged) | |
Camera | Current | (unchanged) | |
Held Item Change (clientbound) | Current | (unchanged) | |
Update View Position | Current | (unchanged) | |
Update View Distance | Current | (unchanged) | |
0x47 | Entity Equipment | Current | Pre |
Spawn Position | Current | (unchanged) | |
Time Update | Current | (unchanged) | |
Title | Current | (unchanged) | |
Entity Sound Effect | Current | (unchanged) | |
Sound Effect | Current | (unchanged) | |
Stop Sound | Current | (unchanged) | |
Player List Header And Footer | Current | (unchanged) | |
NBT Query Response | Current | (unchanged) | |
Collect Item | Current | (unchanged) | |
Entity Teleport | Current | (unchanged) | |
Advancements | Current | (unchanged) | |
Entity Properties | Current | Pre | |
Entity Effect | Current | (unchanged) | |
Declare Recipes | Current | Pre | |
Tags | Current | (unchanged) | |
Play serverbound | |||
0x0E | Interact Entity | Current | Pre |
0x0F | Generate Structure | Pre | |
Keep Alive (serverbound) | Current | (unchanged) | |
Lock Difficulty | Current | (unchanged) | |
Player Position | Current | (unchanged) | |
Player Position And Rotation (serverbound) | Current | (unchanged) | |
Player Rotation | Current | (unchanged) | |
Player Movement | Current | (unchanged) | |
Vehicle Move (serverbound) | Current | (unchanged) | |
Steer Boat | Current | (unchanged) | |
Pick Item | Current | (unchanged) | |
Craft Recipe Request | Current | (unchanged) | |
Player Abilities (serverbound) | Current | Pre | |
Player Digging | Current | (unchanged) | |
Entity Action | Current | (unchanged) | |
Steer Vehicle | Current | (unchanged) | |
0x1D | Recipe Book Data | Current | |
0x1E | Set Displayed Recipe | Pre | |
0x1F | Set Recipe Book State | Pre | |
Name Item | Current | (unchanged) | |
Resource Pack Status | Current | (unchanged) | |
Advancement Tab | Current | (unchanged) | |
Select Trade | Current | (unchanged) | |
Set Beacon Effect | Current | (unchanged) | |
Held Item Change (serverbound) | Current | (unchanged) | |
Update Command Block | Current | (unchanged) | |
Update Command Block Minecart | Current | (unchanged) | |
Creative Inventory Action | Current | (unchanged) | |
Update Jigsaw Block | Current | Pre | |
Update Structure Block | Current | (unchanged) | |
Update Sign | Current | (unchanged) | |
Animation (serverbound) | Current | (unchanged) | |
Spectate | Current | (unchanged) | |
Player Block Placement | Current | (unchanged) | |
Use Item | Current | (unchanged) | |
Login clientbound | |||
0x02 | Login Success | Current | Pre |
New/modified data types
No changes so far.
Entity Metadata
FishingHook
Extends Entity.
Index | Type | Meaning | Default | |
---|---|---|---|---|
7 | VarInt | Hooked entity id + 1, or 0 if there is no hooked entity | 0 | |
8 | Boolean | Is catchable | False |
Abstract Arrow
Extends Entity.
Abstract base class for Tipped Arrow (which is used for regular arrows as well as tipped ones) and Spectral Arrow.
Index | Type | Meaning | Default | |
---|---|---|---|---|
7 | Byte | Bit mask | Meaning | 0 |
0x01 | Is critical | |||
0x02 | Is noclip (used by loyalty tridents when returning) | |||
OptUUID | Unused | Empty | ||
Byte | Peircing level | 0 |
Tipped Arrow
Extends Abstract Arrow.
Used for both tipped and regular arrows. If not tipped, then color is set to -1 and no tipped arrow particles are used.
Index | Type | Meaning | Default | |
---|---|---|---|---|
VarInt | Color (-1 for no particles) | -1 |
Spectral Arrow
Extends Abstract Arrow.
No additional metadata.
Trident
Extends Abstract Arrow.
Index | Type | Meaning | Default | |
---|---|---|---|---|
VarInt | Loyalty level (enchantment) | 0 | ||
Boolean | Has enchantment glint | False |
Strider
Extends Animal.
Index | Type | Meaning | Default | |
---|---|---|---|---|
16 | VarInt | Total time to "boost" with warped fungus on a stick for | 0 | |
17 | Boolean | Is shaking (true unless riding a vehicle or on or in a block tagged with strider_warm_blocks (default: lava)) | false | |
18 | Boolean | Has saddle | false |
Hoglin
Extends Animal.
Index | Type | Meaning | Default | |
---|---|---|---|---|
16 | Boolean | Is immune to zombification | false |
Zoglin
Extends Monster.
Index | Type | Meaning | Default | |
---|---|---|---|---|
15 | Boolean | Is baby | false |
Base Piglin
Extends Monster.
Index | Type | Meaning | Default | |
---|---|---|---|---|
15 | Boolean | Is immune to zombification | false |
Piglin
Extends Base Piglin.
Index | Type | Meaning | Default | |
---|---|---|---|---|
16 | Boolean | Is baby | false | |
17 | Boolean | Is charging crossbow | false | |
18 | Boolean | Is dancing | false |
Piglin Brute
Extends Base Piglin.
No additional metadata.
Wolf
Extends TameableAnimal.
Index | Type | Meaning | Default | |
---|---|---|---|---|
18 | Boolean | Is begging | false | |
19 | VarInt | Collar color (values are those used with dyes) | 14 (Red) | |
20 | VarInt | Anger time | 0 |
Zombie Pigman Zombified Piglin
Extends Zombie.
No additional metadata.
Block Actions
No changes so far.
Inventories
No changes so far.
Plugin Channels
No changes so far.
Play
Clientbound
Chat Message (clientbound)
Identifying the difference between Chat/System Message is important as it helps respect the user's chat visibility options. See processing chat for more info about these positions.
Game info accepts json formatting but does not display it, although the deprecated §-based formatting works. This is not an issue when using the Title packet, so prefer that packet for displaying information in that slot. See MC-119145 for more information.
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
Play | Client | JSON Data | Chat | Limited to 32767 bytes | |
Position | Byte | 0: chat (chat box), 1: system message (chat box), 2: game info (above hotbar). | |||
Sender | UUID | Used by the Notchian client for the disableChat launch option. Setting both longs to 0 will always display the message regardless of the setting. |
Chunk Data
- Main article: Chunk Format
- See also: #Unload Chunk
![]() |
The following information needs to be added to this page: |
How do biomes work now? The biome change happened at the same time as the seed change, but it's not clear how/if biomes could be computed given that it's not the actual seed... (/r/mojira discussion which notes that it seems to be some kind of interpolation, and 3D biomes are only used in the nether) |
The server only sends skylight information for chunk pillars in the Overworld, it's up to the client to know in which dimenison the player is currently located. You can also infer this information from the primary bitmask and the amount of uncompressed bytes sent. This packet also sends all block entities in the chunk (though sending them is not required; it is still legal to send them with Update Block Entity later).
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
Play | Client | Chunk X | Int | Chunk coordinate (block coordinate divided by 16, rounded down) | |
Chunk Z | Int | Chunk coordinate (block coordinate divided by 16, rounded down) | |||
Full chunk | Boolean | See Chunk Format | |||
Primary Bit Mask | VarInt | Bitmask with bits set to 1 for every 16×16×16 chunk section whose data is included in Data. The least significant bit represents the chunk section at the bottom of the chunk column (from y=0 to y=15). | |||
Heightmaps | NBT | Compound containing one long array named MOTION_BLOCKING , which is a heightmap for the highest solid block at each position in the chunk (as a compacted long array with 256 entries at 9 bits per entry totaling 36 longs). The Notchian server also adds a WORLD_SURFACE long array, the purpose of which is unknown, but it's not required for the chunk to be accepted.
| |||
Biomes length | Optional VarInt | Size of the following array. Not present if full chunk is false. | |||
Biomes | Optional array of |
||||
Size | VarInt | Size of Data in bytes | |||
Data | Byte array | See data structure in Chunk Format | |||
Number of block entities | VarInt | Number of elements in the following array | |||
Block entities | Array of NBT Tag | All block entities in the chunk. Use the x, y, and z tags in the NBT to determine their positions. |
Note that the Notchian client requires an Update View Position packet when it crosses a chunk border, otherwise it'll only display render distance + 2 chunks around the chunk it spawned in.
The compacted array format has been adjusted so that individual entries no longer span across multiple longs, affecting the main data array and heightmaps.
New format, 5 bits per block, containing the following references to blocks in a palette (not shown): 122344566480743131516914101202
0020863148418841
0000000000100000100001100011000101001000010000011000100001000001
01018A7260F68C87
0000000100000001100010100111001001100000111101101000110010000111
Update Light
Updates light levels for a chunk.
Packet ID | State | Bound To | Field Name | Field Type | Notes | ||
---|---|---|---|---|---|---|---|
Play | Client | Chunk X | VarInt | Chunk coordinate (block coordinate divided by 16, rounded down) | |||
Chunk Z | VarInt | Chunk coordinate (block coordinate divided by 16, rounded down) | |||||
Trust Edges | Boolean | If edges should be trusted for light updates. | |||||
Sky Light Mask | VarInt | Mask containing 18 bits, with the lowest bit corresponding to chunk section -1 (in the void, y=-16 to y=-1) and the highest bit for chunk section 16 (above the world, y=256 to y=271) | |||||
Block Light Mask | VarInt | Mask containing 18 bits, with the same order as sky light | |||||
Empty Sky Light Mask | VarInt | Mask containing 18 bits, which indicates sections that have 0 for all their sky light values. If a section is set in both this mask and the main sky light mask, it is ignored for this mask and it is included in the sky light arrays (the notchian server does not create such masks). If it is only set in this mask, it is not included in the sky light arrays. | |||||
Empty Block Light Mask | VarInt | Mask containing 18 bits, which indicates sections that have 0 for all their block light values. If a section is set in both this mask and the main block light mask, it is ignored for this mask and it is included in the block light arrays (the notchian server does not create such masks). If it is only set in this mask, it is not included in the block light arrays. | |||||
Sky Light arrays | Length | Array | VarInt | Length of the following array in bytes (always 2048) | |||
Sky Light array | Array of 2048 bytes | There is 1 array for each bit set to true in the sky light mask, starting with the lowest value. Half a byte per light value. | |||||
Block Light arrays | Length | Array | VarInt | Length of the following array in bytes (always 2048) | |||
Block Light array | Array of 2048 bytes | There is 1 array for each bit set to true in the block light mask, starting with the lowest value. Half a byte per light value. |
Individual block or sky light arrays are is given for each block with increasing x coordinates, within rows of increasing z coordinates, within layers of increasing y coordinates. Even-indexed items (those with an even x coordinate, starting at 0) are packed into the low bits, odd-indexed into the high bits.
Join Game
See Protocol Encryption for information on logging in.
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
Play | Client | Entity ID | Int | The player's Entity ID (EID) | |
Is hardcore | Boolean | ||||
Gamemode | Unsigned Byte | 0: Survival, 1: Creative, 2: Adventure, 3: Spectator. | |||
Previous Gamemode | Unsigned Byte | 0: survival, 1: creative, 2: adventure, 3: spectator. The hardcore flag is not included. The previous gamemode. (More information needed) | |||
World Count | VarInt | Size of the following array | |||
World Names | Array of Identifier | Identifiers for all worlds on the server | |||
Dimension Codec | NBT Tag Compound | The full extent of these is still unknown, but the tag represents a dimension and biome registry. See below for the vanilla default. | |||
Dimension | |||||
World Name | Identifier | Name of the world being spawned into | |||
Hashed seed | Long | First 8 bytes of the SHA-256 hash of the world's seed. | |||
Max Players | Was once used by the client to draw the player list, but now is ignored | ||||
Level Type | String Enum (16) | default, flat, largeBiomes, amplified, customized, buffet, default_1_1 | |||
View Distance | VarInt | Render distance (2-32) | |||
Reduced Debug Info | Boolean | If true, a Notchian client shows reduced information on the debug screen. For servers in development, this should almost always be false. | |||
Enable respawn screen | Boolean | Set to false when the doImmediateRespawn gamerule is true | |||
Is Debug | Boolean | True if the world is a debug mode world; debug mode worlds cannot be modified and have predefined blocks | |||
Is Flat | Boolean | True if the world is a superflat world; flat worlds have different void fog and a horizon at y=0 instead of y=63 |
![]() |
The following information needs to be added to this page: |
Lay out and explain the format |
Default Vanilla Dimension/Biome Codec
Known dimension attributes:
Name | Type | Meaning | Values | |
---|---|---|---|---|
name | String | Dimension's name | "minecraft:overworld", "minecraft:the_nether", "minecraft:the_end" or something else | |
piglin_safe | Byte | Whether piglins shake and transform to zombified piglins. | 1: true, 0: false | |
natural | Byte | When false, compasses spin randomly. When true, nether portals can spawn zombified piglins. | 1: true, 0: false | |
ambient_light | Float | How much light the dimension has. | 0.0 to 1.0 | |
fixed_time | Long | If this is set to a number, the time of the day is the specified value. | false, or 0 to 24000 | |
infiniburn | String | A resource location defining what block tag to use for infiniburn. | "" or minecraft resource "minecraft:..." | |
respawn_anchor_works | Byte | Whether players can charge and use respawn anchors. | 1: true, 0: false | |
has_skylight | Byte | Whether the dimension has skylight access or not. | 1: true, 0: false | |
bed_works | Byte | Whether players can use a bed to sleep. | 1: true, 0: false | |
effects | String | ? | "minecraft:overworld", "minecraft:the_nether", "minecraft:the_end" or something else | |
has_raids | Byte | Whether players with the Bad Omen effect can cause a raid. | 1: true, 0: false | |
logical_height | Int | The maximum height to which chorus fruits and nether portals can bring players within this dimension. | 0-256 | |
coordinate_scale | Float | The multiplier applied to coordinates when traveling to the dimension. | 1: true, 0: false | |
ultrawarm | Byte | Whether the dimensions behaves like the nether (water evaporates and sponges dry) or not. Also causes lava to spread thinner. | 1: true, 0: false | |
has_ceiling | Byte | Whether the dimension has a bedrock ceiling or not. When true, causes lava to spread faster. | 1: true, 0: false |
Unlock Recipes
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
Play | Client | ||||
Action | VarInt | 0: init, 1: add, 2: remove | |||
Crafting Recipe Book Open | Boolean | If true, then the crafting recipe book will be open when the player opens its inventory. | |||
Crafting Recipe Book Filter Active | Boolean | If true, then the filtering option is active when the players opens its inventory. | |||
Smelting Recipe Book Open | Boolean | If true, then the smelting recipe book will be open when the player opens its inventory. | |||
Smelting Recipe Book Filter Active | Boolean | If true, then the filtering option is active when the players opens its inventory. | |||
Blast Furance Recipe Book Open | Boolean | If true, then the blast furnace recipe book will be open when the player opens its inventory. | |||
Blast Furance Recipe Book Filter Active | Boolean | If true, then the filtering option is active when the players opens its inventory. | |||
Smoker Recipe Book Open | Boolean | If true, then the smoker recipe book will be open when the player opens its inventory. | |||
Smoker Recipe Book Filter Active | Boolean | If true, then the filtering option is active when the players opens its inventory. | |||
Array size 1 | VarInt | Number of elements in the following array | |||
Recipe IDs | Array of Identifier | ||||
Array size 2 | Optional VarInt | Number of elements in the following array, only present if mode is 0 (init) | |||
Recipe IDs | Optional Array of Identifier, only present if mode is 0 (init) |
Action:
- 0 (init) = All the recipes in the list 2 will added to the recipe book. All the recipes in list 1 will be tagged as displayed, recipes that aren't tagged will be shown in the notification.
- 1 (add) = All the recipes in the list are added and their icon will be shown in the notification.
- 2 (remove) = Remove all the recipes in the list. This allows them to re-displayed when they are readded.
Respawn
To change the player's dimension (overworld/nether/end), send them a respawn packet with the appropriate dimension, followed by prechunks/chunks for the new dimension, and finally a position and look packet. You do not need to unload chunks, the client will do it automatically.
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
Play | Client | Dimension | |||
World Name | Identifier | Name of the world being spawned into | |||
Hashed seed | Long | First 8 bytes of the SHA-256 hash of the world's seed. | |||
Gamemode | Unsigned Byte | 0: survival, 1: creative, 2: adventure, 3: spectator. The hardcore flag is not included | |||
Previous Gamemode | Unsigned Byte | 0: survival, 1: creative, 2: adventure, 3: spectator. The hardcore flag is not included. The previous gamemode. (More information needed) | |||
Level Type | String (16) | Same as Join Game | |||
Is Debug | Boolean | True if the world is a debug mode world; debug mode worlds cannot be modified and have predefined blocks | |||
Is Flat | Boolean | True if the world is a superflat world; flat worlds have different void fog and a horizon at y=0 instead of y=63 | |||
Copy metadata | Boolean | If false, metadata is reset on the respawned player entity. Set to true for dimension changes (including the dimension change triggered by sending client status perform respawn to exit the end poem/credits), and false for normal respawns. |
![]() |
The following information needs to be added to this page: |
Does the new World Name field resolve this same-dimension issue? |
Avoid changing player's dimension to same dimension they were already in unless they are dead. If you change the dimension to one they are already in, weird bugs can occur, such as the player being unable to attack other players in new world (until they die and respawn).
If you must respawn a player in the same dimension without killing them, send two respawn packets, one to a different world and then another to the world you want. You do not need to complete the first respawn; it only matters that you send two packets.
Multi Block Change
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
Play | Client | Long | Chunk section coordinate (encoded chunk x and z with each 22 bits, and section y with 20 bits, from left to right) | ||
Boolean | Always inverse the preceding Update Light packet's "Trust Edges" bool | ||||
Array size | VarInt | Number of elements in the following array | |||
Array of VarLong | Each entry is composed of the block id, shifted right by 12, and the relative block position in the chunk section (4 bits for x, z, and y, from left to right). |
Entity Properties
Sets attributes on the given entity.
Packet ID | State | Bound To | Field Name | Field Type | Notes | ||
---|---|---|---|---|---|---|---|
Play | Client | Entity ID | VarInt | ||||
Number Of Properties | Int | Number of elements in the following array | |||||
Property | Key | Array | See below | ||||
Value | Double | See below | |||||
Number Of Modifiers | VarInt | Number of elements in the following array | |||||
Modifiers | Array of Modifier Data | See Attribute#Modifiers. Modifier Data defined below. |
Known Key values (see also Attribute#Modifiers):
Key | Default | Min | Max | Label |
---|---|---|---|---|
20.0 | 0.0 | 1024.0 | Max Health | |
32.0 | 0.0 | 2048.0 | Follow Range | |
0.0 | 0.0 | 1.0 | Knockback Resistance | |
0.7 | 0.0 | 1024.0 | Movement Speed | |
2.0 | 0.0 | 2048.0 | Attack Damage | |
4.0 | 0.0 | 1024.0 | Attack Speed | |
0.4 | 0.0 | 1024.0 | Flying Speed | |
generic.armor | 0.0 | 0.0 | 30.0 | Armor |
0.0 | 0.0 | 20.0 | Armor Toughness | |
0.0 | 0.0 | 5.0 | — | |
generic.luck | 0.0 | -1024.0 | 1024.0 | Luck |
0.7 | 0.0 | 2.0 | Jump Strength | |
0.0 | 0.0 | 1.0 | Spawn Reinforcements Chance | |
generic.reachDistance | 5.0 | 0.0 | 1024.0 | Player Reach Distance (Forge only) |
forge.swimSpeed | 1.0 | 0.0 | 1024.0 | Swimming Speed (Forge only) |
Unknown attributes will cause a game crash (MC-150405) due to the default minimum being larger than the default value.
Modifier Data structure:
Field Name | Field Type | Notes |
---|---|---|
UUID | UUID | |
Amount | Double | May be positive or negative |
Operation | Byte | See below |
The operation controls how the base value of the modifier is changed.
- 0: Add/subtract amount
- 1: Add/subtract amount percent of the current value
- 2: Multiply by amount percent
All of the 0's are applied first, and then the 1's, and then the 2's.
Declare Recipes
Packet ID | State | Bound To | Field Name | Field Type | Notes | ||
---|---|---|---|---|---|---|---|
Play | Client | Num Recipes | VarInt | Number of elements in the following array | |||
Recipe | Recipe ID | Array | Identifier | ||||
Type | String | The recipe type, see below | |||||
Data | Optional, varies | Additional data for the recipe. For some types, there will be no data. |
Recipe types:
Type | Description | Data | ||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
crafting_shapeless
|
Shapeless crafting recipe. All items in the ingredient list must be present, but in any order/slot. | As follows:
| ||||||||||||||||||
crafting_shaped
|
Shaped crafting recipe. All items must be present in the same pattern (which may be flipped horizontally or translated) | As follows:
| ||||||||||||||||||
crafting_special_armordye
|
Recipe for dying leather armor | None | ||||||||||||||||||
crafting_special_bookcloning
|
Recipe for copying contents of written books | |||||||||||||||||||
crafting_special_mapcloning
|
Recipe for copying maps | |||||||||||||||||||
crafting_special_mapextending
|
Recipe for adding paper to maps | |||||||||||||||||||
crafting_special_firework_rocket
|
Recipe for making firework rockets | |||||||||||||||||||
crafting_special_firework_star
|
Recipe for making firework stars | |||||||||||||||||||
crafting_special_firework_star_fade
|
Recipe for making firework stars fade between multiple colors | |||||||||||||||||||
crafting_special_repairitem
|
Recipe for repairing items via crafting | |||||||||||||||||||
crafting_special_tippedarrow
|
Recipe for crafting tipped arrows | |||||||||||||||||||
crafting_special_bannerduplicate
|
Recipe for copying banner patterns | |||||||||||||||||||
crafting_special_banneraddpattern
|
Recipe for adding patterns to banners | |||||||||||||||||||
crafting_special_shielddecoration
|
Recipe for applying a banner's pattern to a shield | |||||||||||||||||||
crafting_special_shulkerboxcoloring
|
Recipe for recoloring a shulker box | |||||||||||||||||||
smelting
|
Smelting recipe | As follows:
| ||||||||||||||||||
blasting
|
Blast furnace recipe | |||||||||||||||||||
smoking
|
Smoker recipe | |||||||||||||||||||
campfire_cooking
|
Campfire recipe | |||||||||||||||||||
stonecutting
|
Stonecutter recipe | As follows:
| ||||||||||||||||||
smithing
|
Smithing table recipe | As follows:
|
Ingredient is defined as:
Name | Type | Description |
---|---|---|
Count | VarInt | Number of elements in the following array |
Items | Array of Slot | Any item in this array may be used for the recipe. The count of each item should be 1. |
Serverbound
Interact Entity
This packet is sent from the client to the server when the client attacks or right-clicks another entity (a player, minecart, etc).
A Notchian server only accepts this packet if the entity being attacked/used is visible without obstruction and within a 4-unit radius of the player's position.
Note that middle-click in creative mode is interpreted by the client and sent as a Creative Inventory Action packet instead.
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
0x0E | Play | Server | Entity ID | VarInt | The ID of the entity to interact |
Type | VarInt Enum | 0: interact, 1: attack, 2: interact at | |||
Target X | Optional Float | Only if Type is interact at | |||
Target Y | Optional Float | Only if Type is interact at | |||
Target Z | Optional Float | Only if Type is interact at | |||
Hand | Optional VarInt Enum | Only if Type is interact or interact at; 0: main hand, 1: off hand | |||
Sneaking | Boolean | If the client is sneaking. |
Generate Structure
Sent when Generate is pressed on the Jigsaw Block interface.
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
0x0F | Play | Server | Location | Position | Block entity location |
Levels | VarInt | Value of the levels slider/max depth to generate | |||
Keep Jigsaws | Boolean |
Player Abilities (serverbound)
The latter 2 fields are used to indicate the walking and flying speeds respectively, while the first field is used to determine the value of 4 booleans.
The vanilla client sends this packet when the player starts/stops flying with the Flags parameter changed accordingly. All other parameters are ignored by the vanilla server.
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
Play | Server | Flags | Byte | Bit mask. | |
Flying Speed | Float | ||||
Walking Speed | Float |
Set Displayed Recipe
Replaces Recipe Book Data, type 0.
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
0x1E | Play | Server | Recipe ID | Identifier |
Set Recipe Book State
Replaces Recipe Book Data, type 1.
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
0x1F | Play | Server | Book ID | VarInt enum | 0: crafting, 1: furnace, 2: blast furnace, 3: smoker |
Book Open | Boolean | ||||
Filter Active | Boolean |
Update Jigsaw Block
Sent when Done is pressed on the Jigsaw Block interface.
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
Play | Server | Location | Position | Block entity location | |
Attachment type | Identifier | ||||
Name | Identifier | ||||
Target | Identifier | ||||
Identifier | |||||
Final state | String | "Turns into" on the GUI, final_state in NBT
| |||
Joint type | String | rollable if the attached piece can be rotated, else aligned
|
Entity Equipment
Packet ID | State | Bound To | Field Name | Field Type | Notes | ||
---|---|---|---|---|---|---|---|
0x47 | Play | Client | Entity ID | VarInt | Entity's EID | ||
Slot | VarInt Enum | Equipment slot. 0: main hand, 1: off hand, 2–5: armor slot (2: boots, 3: leggings, 4: chestplate, 5: helmet) | |||||
Item | Slot | ||||||
Equipment | Slot | Array | Byte Enum | Equipment slot. 0: main hand, 1: off hand, 2–5: armor slot (2: boots, 3: leggings, 4: chestplate, 5: helmet). Also has the top bit set if another entry follows, and otherwise unset if this is the last item in the array. | |||
Item | Slot |
Handshaking
Clientbound
There are no clientbound packets in the Handshaking state, since the protocol immediately switches to a different state after the client sends the first packet.
Serverbound
Handshake
This causes the server to switch into the target state.
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
0x00 | Handshaking | Server | Protocol Version | VarInt | See protocol version numbers (currently |
Server Address | String | Hostname or IP, e.g. localhost or 127.0.0.1, that was used to connect. The Notchian server does not use this information. Note that SRV records are a complete redirect, e.g. if _minecraft._tcp.example.com points to mc.example.org, users connecting to example.com will provide mc.example.org as server address in addition to connecting to it. | |||
Server Port | Unsigned Short | Default is 25565. The Notchian server does not use this information. | |||
Next State | VarInt Enum | 1 for status, 2 for login |
Status
Clientbound
No changes so far.
Serverbound
No changes so far.
Login
Clientbound
Login Success
Packet ID | State | Bound To | Field Name | Field Type | Notes |
---|---|---|---|---|---|
0x02 | Login | Client | UUID | ||
Username | String (16) |
This packet switches the connection state to play.
Serverbound
No changes so far.