The interface

What a client shows its player besides the field: the view and camera, input locks, the minimap and text over the screen. Tips, quests, highlights and the tutorial are in Tutorial and guidance.

The view

A client reports where its view sits and which way it faces with Camera, which a server answers (see Ordering). A client tells a server what it has selected with SelectObject, and as it locks its view to its champion or releases it with CameraLock.

A server carries a client’s view from one place to another with MoveCamera. A server can also lock or free a client’s camera with CameraLockSet, which the client answers with CameraLock except while it holds its camera itself, and set a point a player’s view keeps to with CameraBehaviour.

In 3.01–3.10

A client sends no Camera while its camera is locked: a server that needs a client’s view reports frees its camera with CameraLockSet.

In 3.10

A client ignores CameraLockSet that arrives while it holds its camera itself, and answers nothing.

Input

A server locks or unlocks kinds of input, such as movement, spells or the shop, with InputLock or InputLockToggled.

In 3.01–3.10

A client keeps every lock a message sets or clears, and later input obeys them, but it acts on a lock at once only where the message’s mask is exactly one of 1, 4, 8, 16, 32 or 128.

In 3.10

A watching client ignores InputLock.

The minimap and text on screen

MinimapIcon changes what a client draws for a unit on its map. A server can float text over a unit (FloatingText, UnitText), warn a player who seems to be away (AfkWarning), and take the interface down (HudDisabled).

Messages

Each message of this system in this book, with each layout it has across the book’s patches and every note its definition carries. A layout is the message’s body, after the header its channel’s family puts in front (see Messages).

`Camera`

What a client sends to say where its view sits and which way it faces. Each report is sent once where a server answers it, and again and again where a server does not. The header names no object: it carries zero.

Definition.

In every range of this book

Command 45 on requests, sent by the client, unreliable.

Field	Type	What it is
positionX	f32
positionY	f32
positionZ	f32
directionX	f32
directionY	f32
directionZ	f32
clientId	u32	The client id of the client the view belongs to.
syncId	u8	Names this report, counting up as the view moves. A client sends the report again until a server returns the name.

`SelectObject`

What a client sends as the object it has selected changes. The header names no object: it carries zero.

Definition.

In every range of this book

Command 175 on requests, sent by the client, reliable.

Field	Type	What it is
clientId	u32	The client id of the client selecting: the one its Registered gave it. Zero is a client id like any other rather than an absence.
selected	u32	The network object now selected, or zero where none is.

Vectors (1)

one-on-3-15

`CameraLock`

What a client sends as it locks its view to a unit or releases it. The header names no object: it carries zero.

Definition.

In every range of this book

Command 129 on requests, sent by the client, reliable.

A client sends it whenever its lock changes: by the player, or as the game forces a lock or lifts one. It sends none while playing a replay.

Field	Type	What it is
state	1-byte bits
state.locked	bit 0	Set while the view follows a unit.
state.unused	bit 1 to 7	Unused; a client writes zero.
clientId	u32	The client id of the client locking. Zero is a client id like any other rather than an absence.

Vectors (1)

one-on-3-15

`MoveCamera`

What a server sends to carry a client’s view from one place to another. The header names the champion of the player it is sent to.

Definition.

In every range of this book

Command 36 on events, sent by the server, reliable.

Where the header names a champion, only the client whose own champion it is moves its view; others take the message and do nothing. Where the header carries zero, a client moves its view to to over travelTime, how and from having no effect.

Field	Type	What it is
how	1-byte bits
how.fromWhereItIs	bit 0	Set to start from where the camera stands, fromX, fromY and fromZ having no effect; clear to start from them.
how.unused1	bit 1	Unused; a server writes zero.
how.unused	bit 2 to 7	Unused; a server writes zero.
fromX	f32	Where the view starts, along one ground axis, in world units.
fromY	f32	Where the view starts, in height, in world units.
fromZ	f32	Where the view starts, along the other ground axis, in world units.
toX	f32	Where the view ends, along one ground axis, in world units.
toY	f32	Where the view ends, in height, in world units.
toZ	f32	Where the view ends, along the other ground axis, in world units.
travelTime	f32	How long the view takes to get there, in seconds. The view moves at an even speed over the distance along the ground.

`CameraLockSet`

What a server sends to lock the camera to the champion or free it. A client answers with CameraLock. The header names no object: a server writes zero.

Definition.

In every range of this book

Command 120 on events, sent by the server, reliable.

A client ignores the message while something of its own holds the camera. It sends no CameraLock while playing a replay.

Field	Type	What it is
state	1-byte bits	Whether the camera is locked.
state.locked	bit 0	Set to lock the camera, clear to free it.
state.unused	bit 1 to 7	Unused; a server writes zero.

Vectors (1)

one-on-3-15

`CameraBehaviour`

What a server sends to set a point a champion’s player’s view keeps to. The header names the champion.

Definition.

In every range of this book

Command 114 on events, sent by the server, reliable.

Field	Type	What it is
x	f32	Along one ground axis, in world units.
y	f32	In height, in world units.
z	f32	Along the other ground axis, in world units.

`InputLock`

What a server sends to lock or unlock a kind of input on a client. The header carries zero.

Definition.

In every range of this book

Command 132 on events, sent by the server, reliable.

A client ignores it while playing a replay.

Field	Type	What it is
category	u32	Which input, as a set of bits. Values: 1 cameraLocking, 2 movement, 4 abilities, 8 summonerSpells, 16 shop, 32 chat, 64 minimapMovement, 128 cameraMovement.
state	1-byte bits	Whether to lock.
state.locked	bit 0	Set to lock, clear to unlock.
state.unused	bit 1 to 7	Unused; a server writes zero.

Vectors (2)

another-on-3-15, one-on-3-15

`InputLockToggled`

What a server sends to turn kinds of input off where they are on, or on where they are off. The header carries zero.

Definition.

In every range of this book

Command 155 on events, sent by the server, reliable.

A client acts on the change at once only where exactly one lock is set; any other value still changes what is locked, and takes effect as the player next tries.

Field	Type	What it is
locks	u32	Each lock set flips. Values: 1 cameraLock, 2 movement, 4 spells, 8 summonerSpells, 16 shop, 32 chat, 64 minimapMovement, 128 cameraMovement.

Vectors (1)

one-on-3-15

`MinimapIcon`

What a server sends to change what a client draws for a unit on its map. The header names no object: it carries zero.

Definition.

In every range of this book

Command 216 on events, sent by the server, reliable.

A client does nothing unless unit is a unit it holds that can be attacked.

Field	Type	What it is
unit	u32	The unit this is about.
changeIcon	u8	1 to replace the unit’s minimap icon with icon; 0 leaves it, and icon has no effect.
icon	text, 64 bytes	The name the client loads the mark under. Written out in full and padded with zero bytes to the width above.
changeBorder	u8	1 to replace the unit’s ring with border, and what it does with borderScript; 0 leaves both, and neither has any effect.
border	text, 64 bytes	The name the client loads the ring around the mark under, written and padded as above.

Vectors (1)

one-on-3-15

`FloatingText`

What a server sends to show text floating over a unit. The header names the unit.

Definition.

In 3.01–3.14

Command 24 on events, sent by the server, reliable.

Field	Type	What it is
unused	u32	Unused; a server writes zero.
delay	f32	Unused; a server writes 2.
slot	i32	Where the text goes. 0 floats it over the unit while the unit is in the client’s own view, the text looked up as a key into the client’s own text. 1 to 50 writes it, in colour, to that line of a debugging display, only where the unit is the one the player has selected. A client does nothing for any other value.
error	u8	Nonzero has a client ignore the whole message.
colour	u8	The text’s colour on the debugging display; it has no effect for slot 0.
style	u32	Which style of floating text.
text	text, ended by a zero byte	The text, ended by a zero byte; the two take at most 1024 bytes.

Vectors (2)

another-on-3-14, one-on-3-14

In 3.15

Command 24 on events, sent by the server, reliable.

Field	Type	What it is
delay	f32	Unused; a server writes 2.
slot	i32	Where the text goes. 0 floats it over the unit while the unit is in the client’s own view, the text looked up as a key into the client’s own text. 1 to 50 writes it, in colour, to that line of a debugging display, only where the unit is the one the player has selected. A client does nothing for any other value.
error	u8	Nonzero has a client ignore the whole message.
colour	u8	The text’s colour on the debugging display; it has no effect for slot 0.
style	u32	Which style of floating text.
length	u32	The text’s length in bytes, counting its zero byte.
text	text, sized by length	The text.

`UnitText`

What a server sends to float a line of the client’s own text over a unit, as combat text floats. A client shows it only where the unit is in its sight, and not while playing a replay. The header carries zero.

Definition.

In 3.01

Command 25 on events, sent by the server, reliable.

Field	Type	What it is
unit	u32	The unit to float it over: one that can be damaged.
style	u8	How the line looks, from 0 to 24. A client shows debug lines to nobody. Values: 0 invulnerable, 1 special, 2 heal, 3 manaHeal, 4 manaDamage, 5 dodge, 6 physicalCritical, 7 experience, 8 gold, 9 level, 10 disable, 11 questReceived, 12 questComplete, 13 score, 14 physicalDamage, 15 magicDamage, 16 trueDamage, 17 enemyPhysicalDamage, 18 enemyMagicDamage, 19 enemyTrueDamage, 20 enemyPhysicalCritical, 21 countdown, 22 damage, 23 critical, 24 debug.
number	i32	A number put into the text where it asks for one.
text	text, 128 bytes	A key into the client’s own text. The text ends at its first zero byte, which falls within the field.

Vectors (1)

disable-on-3-01

In 3.02–3.8

Command 25 on events, sent by the server, reliable.

Field	Type	What it is
unit	u32	The unit to float it over: one that can be damaged.
style	u8	How the line looks, from 0 to 25. A client shows debug lines to nobody. Values: 0 invulnerable, 1 special, 2 heal, 3 manaHeal, 4 manaDamage, 5 dodge, 6 physicalCritical, 7 experience, 8 gold, 9 level, 10 disable, 11 questReceived, 12 questComplete, 13 score, 14 physicalDamage, 15 magicDamage, 16 trueDamage, 17 enemyPhysicalDamage, 18 enemyMagicDamage, 19 enemyTrueDamage, 20 enemyPhysicalCritical, 21 countdown, 22 onMyWay, 23 damage, 24 critical, 25 debug.
number	i32	A number put into the text where it asks for one.
text	text, 128 bytes	A key into the client’s own text. The text ends at its first zero byte, which falls within the field.

Vectors (1)

disable-on-3-8

In 3.9–3.11

Command 25 on events, sent by the server, reliable.

Field	Type	What it is
unit	u32	The unit to float it over: one that can be damaged.
style	u8	How the line looks, from 0 to 26. A client shows debug lines to nobody. Values: 0 invulnerable, 1 special, 2 heal, 3 manaHeal, 4 manaDamage, 5 dodge, 6 physicalCritical, 7 experience, 8 gold, 9 level, 10 disable, 11 questReceived, 12 questComplete, 13 score, 14 physicalDamage, 15 magicDamage, 16 trueDamage, 17 enemyPhysicalDamage, 18 enemyMagicDamage, 19 enemyTrueDamage, 20 enemyPhysicalCritical, 21 countdown, 22 onMyWay, 24 damage, 25 critical, 26 debug.
number	i32	A number put into the text where it asks for one.
text	text, 128 bytes	A key into the client’s own text. The text ends at its first zero byte, which falls within the field.

Vectors (1)

disable-on-3-11

In 3.12–3.15

Command 25 on events, sent by the server, reliable.

Field	Type	What it is
unit	u32	The unit to float it over: one that can be damaged.
style	u8	How the line looks, from 0 to 27. A client shows debug lines to nobody. Values: 0 invulnerable, 1 special, 2 heal, 3 manaHeal, 4 manaDamage, 5 dodge, 6 physicalCritical, 7 magicCritical, 8 experience, 9 gold, 10 level, 11 disable, 12 questReceived, 13 questComplete, 14 score, 15 physicalDamage, 16 magicDamage, 17 trueDamage, 18 enemyPhysicalDamage, 19 enemyMagicDamage, 20 enemyTrueDamage, 21 enemyPhysicalCritical, 22 countdown, 23 onMyWay, 24 absorbed, 25 damage, 26 critical, 27 debug.
number	i32	A number put into the text where it asks for one.
text	text, 128 bytes	A key into the client’s own text. The text ends at its first zero byte, which falls within the field.

Vectors (1)

level-on-3-12

`AfkWarning`

What a server sends to warn the player that they seem to be away, in a popup with one button that only closes it. It carries nothing of its own. The header carries zero.

Definition.