camera-control
Camera Control in Decentraland
Reading Camera State
Access the camera's current position and rotation via the reserved engine.CameraEntity:
import { engine, Transform } from '@dcl/sdk/ecs'
function trackCamera() {
if (!Transform.has(engine.CameraEntity)) return
const cameraTransform = Transform.get(engine.CameraEntity)
console.log('Camera position:', cameraTransform.position)
console.log('Camera rotation:', cameraTransform.rotation)
}
engine.addSystem(trackCamera)
Camera Mode Detection
Check whether the player is in first-person or third-person:
import { engine, CameraMode, CameraType } from '@dcl/sdk/ecs'
function checkCameraMode() {
if (!CameraMode.has(engine.CameraEntity)) return
const cameraMode = CameraMode.get(engine.CameraEntity)
if (cameraMode.mode === CameraType.CT_FIRST_PERSON) {
console.log('First person camera')
} else if (cameraMode.mode === CameraType.CT_THIRD_PERSON) {
console.log('Third person camera')
}
}
engine.addSystem(checkCameraMode)
Camera Mode Values
CameraType.CT_FIRST_PERSON // First-person view
CameraType.CT_THIRD_PERSON // Third-person view (default)
CameraModeArea (Force Camera in a Region)
Force a specific camera mode when the player enters an area:
import { engine, Transform, CameraModeArea, CameraType } from '@dcl/sdk/ecs'
import { Vector3 } from '@dcl/sdk/math'
const fpArea = engine.addEntity()
Transform.create(fpArea, { position: Vector3.create(8, 1.5, 8) })
CameraModeArea.create(fpArea, {
area: Vector3.create(6, 4, 6), // 6x4x6 meter box
mode: CameraType.CT_FIRST_PERSON // Force first-person inside
})
When the player leaves the area, the camera reverts to their preferred mode.
VirtualCamera (Cinematic Cameras)
Create scripted camera positions for cutscenes or special views:
import { engine, Transform, VirtualCamera, MainCamera } from '@dcl/sdk/ecs'
import { Vector3, Quaternion } from '@dcl/sdk/math'
const cinematicCam = engine.addEntity()
Transform.create(cinematicCam, {
position: Vector3.create(8, 5, 2),
rotation: Quaternion.fromEulerDegrees(-20, 0, 0)
})
VirtualCamera.create(cinematicCam, {
defaultTransition: {
transitionMode: VirtualCamera.Transition.Speed(1.0)
}
})
// Activate the virtual camera
MainCamera.getMutable(engine.CameraEntity).virtualCameraEntity = cinematicCam
// Return to normal camera
MainCamera.getMutable(engine.CameraEntity).virtualCameraEntity = undefined
Transition Modes
VirtualCamera.Transition.Speed(1.0) // Speed-based smooth transition
VirtualCamera.Transition.Time(2) // Time-based transition (2 seconds)
Look-At Target
Make the virtual camera track an entity:
const target = engine.addEntity()
Transform.create(target, { position: Vector3.create(8, 1, 8) })
VirtualCamera.create(cinematicCam, {
lookAtEntity: target,
defaultTransition: {
transitionMode: VirtualCamera.Transition.Speed(2.0)
}
})
// Activate
MainCamera.getMutable(engine.CameraEntity).virtualCameraEntity = cinematicCam
Tracking Camera Position
Poll camera position each frame for camera-triggered events:
import { engine, Transform } from '@dcl/sdk/ecs'
import { Vector3 } from '@dcl/sdk/math'
let lastNotifiedZone = ''
function cameraZoneSystem() {
if (!Transform.has(engine.CameraEntity)) return
const camPos = Transform.get(engine.CameraEntity).position
let currentZone = ''
if (camPos.y > 10) {
currentZone = 'sky'
} else if (camPos.x < 4) {
currentZone = 'west'
} else {
currentZone = 'center'
}
if (currentZone !== lastNotifiedZone) {
lastNotifiedZone = currentZone
console.log('Camera entered zone:', currentZone)
}
}
engine.addSystem(cameraZoneSystem)
Common Patterns
Camera-Triggered Events
Use the camera position to trigger actions when the player looks at a specific area:
function cameraLookTrigger() {
const camTransform = Transform.get(engine.CameraEntity)
const targetPos = Vector3.create(8, 2, 8)
const distance = Vector3.distance(camTransform.position, targetPos)
if (distance < 5) {
// Player is close — check if camera is pointing at target
// Use raycasting for precise look detection (see add-interactivity skill)
}
}
engine.addSystem(cameraLookTrigger)
Following an NPC
Move camera to track an NPC by updating a VirtualCamera's Transform:
function followNpcCamera(dt: number) {
const npcPos = Transform.get(npcEntity).position
const camTransform = Transform.getMutable(cinematicCam)
// Position camera behind and above the NPC
camTransform.position = Vector3.create(
npcPos.x - 2,
npcPos.y + 3,
npcPos.z - 2
)
}
engine.addSystem(followNpcCamera)
Freezing player during cutscenes? Combine VirtualCamera with
InputModifierfrom the advanced-input skill to prevent player movement during cinematic sequences.
Best Practices
- Only one VirtualCamera should be active at a time
- Use
CameraModeAreato force first-person in tight indoor spaces - Keep transition speeds between 0.5 and 3.0 for comfortable camera movement
- Always provide a way for the player to exit forced camera modes (e.g., leave the area)
- Read camera state via
engine.CameraEntity— never try to write to it directly - For look-at detection, combine camera position with raycasting (see
add-interactivityskill) - Camera control is read-only outside of VirtualCamera and CameraModeArea — you cannot directly move the player's camera
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