Player and Avatar System in Decentraland

Player Position and Movement

Access the player's position via the reserved engine.PlayerEntity:

import { engine, Transform } from '@dcl/sdk/ecs'

function trackPlayer() {
  if (!Transform.has(engine.PlayerEntity)) return

  const playerTransform = Transform.get(engine.PlayerEntity)
  console.log('Player position:', playerTransform.position)
  console.log('Player rotation:', playerTransform.rotation)
}

engine.addSystem(trackPlayer)

Distance-Based Logic

import { Vector3 } from '@dcl/sdk/math'

function proximityCheck() {
  const playerPos = Transform.get(engine.PlayerEntity).position
  const npcPos = Transform.get(npcEntity).position
  const distance = Vector3.distance(playerPos, npcPos)

  if (distance < 5) {
    console.log('Player is near the NPC')
  }
}

engine.addSystem(proximityCheck)

Player Profile Data

Get the player's name, wallet address, and guest status:

import { getPlayer } from '@dcl/sdk/src/players'

function main() {
  const player = getPlayer()
  if (player) {
    console.log('Name:', player.name)
    console.log('User ID:', player.userId)
    console.log('Is guest:', player.isGuest)
  }
}

• userId — the player's Ethereum wallet address (or guest ID)
• isGuest — true if the player hasn't connected a wallet

Avatar Attachments

Attach 3D objects to a player's avatar:

import { engine, Transform, GltfContainer, AvatarAttach, AvatarAnchorPointType } from '@dcl/sdk/ecs'

const hat = engine.addEntity()
GltfContainer.create(hat, { src: 'models/hat.glb' })

// Attach to the local player's avatar
AvatarAttach.create(hat, {
  anchorPointId: AvatarAnchorPointType.AAPT_NAME_TAG
})

Anchor Points

AvatarAnchorPointType.AAPT_NAME_TAG      // Above the head
AvatarAnchorPointType.AAPT_RIGHT_HAND    // Right hand
AvatarAnchorPointType.AAPT_LEFT_HAND     // Left hand
AvatarAnchorPointType.AAPT_POSITION      // Avatar root position

Attach to a Specific Player

AvatarAttach.create(hat, {
  avatarId: '0x123...abc',  // Target player's wallet address
  anchorPointId: AvatarAnchorPointType.AAPT_RIGHT_HAND
})

Triggering Emotes

Default Emotes

import { triggerEmote } from '~system/RestrictedActions'

// Play a built-in emote
triggerEmote({ predefinedEmote: 'robot' })
triggerEmote({ predefinedEmote: 'wave' })
triggerEmote({ predefinedEmote: 'clap' })

Custom Scene Emotes

import { triggerSceneEmote } from '~system/RestrictedActions'

// Play a custom emote animation (file must end with _emote.glb)
triggerSceneEmote({
  src: 'animations/Snowball_Throw_emote.glb',
  loop: false
})

Notes:

• Emotes play only while the player is standing still — walking or jumping interrupts them
• Custom emote files must have the _emote.glb suffix

NPC Avatars

Create avatar-shaped NPCs using AvatarShape:

import { engine, Transform, AvatarShape } from '@dcl/sdk/ecs'
import { Vector3 } from '@dcl/sdk/math'

const npc = engine.addEntity()
Transform.create(npc, { position: Vector3.create(8, 0, 8) })

AvatarShape.create(npc, {
  id: 'npc-1',
  name: 'Guard',
  bodyShape: 'urn:decentraland:off-chain:base-avatars:BaseMale',  // or BaseFemale
  wearables: [
    'urn:decentraland:off-chain:base-avatars:eyebrows_00',
    'urn:decentraland:off-chain:base-avatars:mouth_00',
    'urn:decentraland:off-chain:base-avatars:eyes_00',
    'urn:decentraland:off-chain:base-avatars:blue_tshirt',
    'urn:decentraland:off-chain:base-avatars:brown_pants',
    'urn:decentraland:off-chain:base-avatars:classic_shoes',
    'urn:decentraland:off-chain:base-avatars:short_hair'
  ],
  hairColor: { r: 0.92, g: 0.76, b: 0.62 },  // RGB values 0-1
  skinColor: { r: 0.94, g: 0.85, b: 0.6 },   // RGB values 0-1
  emotes: []
})

Mannequin (Show Only Wearables)

Display just the wearables without a full avatar body:

AvatarShape.create(mannequin, {
  id: 'mannequin-1',
  name: 'Display',
  wearables: [
    'urn:decentraland:matic:collections-v2:0x90e5cb2d673699be8f28d339c818a0b60144c494:0'
  ],
  show_only_wearables: true
})

NPC avatars are static — they display the avatar model but don't move or animate on their own. Combine with Animator or Tween for movement.

Avatar Modifier Areas

Modify how avatars appear or behave in a region:

import { engine, Transform, AvatarModifierArea, AvatarModifierType } from '@dcl/sdk/ecs'
import { Vector3 } from '@dcl/sdk/math'

const modifierArea = engine.addEntity()
Transform.create(modifierArea, {
  position: Vector3.create(8, 1.5, 8),
  scale: Vector3.create(4, 3, 4)
})

AvatarModifierArea.create(modifierArea, {
  area: { box: Vector3.create(4, 3, 4) },
  modifiers: [AvatarModifierType.AMT_HIDE_AVATARS],
  excludeIds: ['0x123...abc']  // Optional: exclude specific players
})

Available Modifiers

AvatarModifierType.AMT_HIDE_AVATARS       // Hide all avatars in the area
AvatarModifierType.AMT_DISABLE_PASSPORTS  // Disable clicking on avatars to see profiles
AvatarModifierType.AMT_DISABLE_JUMPING    // Prevent jumping in the area

Movement Constraints

// Prevent jumping in a specific area
const constraintArea = engine.addEntity()
Transform.create(constraintArea, {
  position: Vector3.create(8, 5, 8),
  scale: Vector3.create(6, 10, 6)
})

AvatarModifierArea.create(constraintArea, {
  area: { box: Vector3.create(6, 10, 6) },
  modifiers: [AvatarModifierType.AMT_DISABLE_JUMPING]
})

Teleporting the Player

You MUST use movePlayerTo from ~system/RestrictedActions to move or teleport the player. Setting Transform.getMutable(engine.PlayerEntity).position does NOT work — the runtime ignores direct writes to the player transform.

import { movePlayerTo } from '~system/RestrictedActions'

// Move player to a position
void movePlayerTo({
  newRelativePosition: Vector3.create(8, 0, 8)
})

// Move player with camera direction
void movePlayerTo({
  newRelativePosition: Vector3.create(8, 0, 8),
  cameraTarget: Vector3.create(8, 1, 12)
})

Avatar Change Listeners

React to avatar changes in real-time:

import { AvatarEmoteCommand, AvatarBase, AvatarEquippedData } from '@dcl/sdk/ecs'

// Detect when any player triggers an emote
AvatarEmoteCommand.onChange(engine.PlayerEntity, (cmd) => {
  if (cmd) console.log('Emote played:', cmd.emoteUrn)
})

// Detect avatar appearance changes (wearables, skin color, etc.)
AvatarBase.onChange(engine.PlayerEntity, (base) => {
  if (base) console.log('Avatar name:', base.name)
})

// Detect equipment changes
AvatarEquippedData.onChange(engine.PlayerEntity, (equipped) => {
  if (equipped) console.log('Wearables changed:', equipped.wearableUrns)
})

Additional Anchor Points

Beyond the commonly used anchor points, the full list includes:

• AvatarAnchorPointType.AAPT_POSITION — avatar feet position
• AvatarAnchorPointType.AAPT_NAME_TAG — above the name tag
• AvatarAnchorPointType.AAPT_LEFT_HAND / AAPT_RIGHT_HAND
• AvatarAnchorPointType.AAPT_HEAD — head bone
• AvatarAnchorPointType.AAPT_NECK — neck bone

Best Practices

• Always check Transform.has(engine.PlayerEntity) before reading player data — it may not be ready on the first frame
• Use getPlayer() to check isGuest before attempting wallet-dependent features
• AvatarAttach requires the target player to be in the same scene — attachments disappear when the player leaves
• Custom emote files must use the _emote.glb naming convention
• Use AvatarModifierArea with AMT_HIDE_AVATARS for private rooms or puzzle areas
• Add excludeIds to modifier areas when you want specific players (like the scene owner) to remain visible
• Never use Transform.getMutable(engine.PlayerEntity) to move the player — it does not work. Always use movePlayerTo from ~system/RestrictedActions
• Transform.get(engine.PlayerEntity) is valid for reading position only

For component field details, see {baseDir}/../../context/components-reference.md.