How To

Apply Camera Behaviors


Apply Camera Behaviors

Bouncing behavior

The bouncing behavior (BABYLON.BouncingBehavior) is designed to produce a small bouncing effect when an ArcRotateCamera reaches the lowerRadiusLimit or the upperRadiusLimit.

The bouncing behavior can be configured using the following properties:

  • transitionDuration: Define the duration of the animation, in milliseconds. By default the value is set to 450ms
  • lowerRadiusTransitionRange: Define the length of the distance animated by the transition when lower radius is reached. By default the value is set to 2
  • upperRadiusTransitionRange: Define the length of the distance animated by the transition when upper radius is reached. By default the value is set to -2
  • autoTransitionRange: Define a value indicating if the lowerRadiusTransitionRange and upperRadiusTransitionRange are defined automatically. Transition ranges will be set to 5% of the bounding box diagonal in world space

You can easily turn on this behavior on an ArcRotateCamera with the following code:

camera.useBouncingBehavior = true;

You can find a live demo here: https://www.babylonjs-playground.com/#6FBD14 -


AutoRotation Behavior

The autoRotation behavior (BABYLON.AutoRotationBehavior) is designed to create a smooth rotation of an ArcRotateCamera when there is no user interaction.

This behavior can be configured with the following properties:

  • idleRotationSpeed: Speed at which the camera rotates around the mesh
  • idleRotationWaitTime: Time (in milliseconds) to wait after user interaction before the camera starts rotating
  • idleRotationSpinupTime: Time (milliseconds) to take to spin up to the full idle rotation speed
  • zoomStopsAnimation: Flag that indicates if user zooming should stop animation

You can easily turn on this behavior on an ArcRotateCamera with the following code:

camera.useAutoRotationBehavior = true;

You can find a live demo here: https://www.babylonjs-playground.com/#6FBD14#1 -


Framing Behavior

The framing behavior (BABYLON.FramingBehavior) is designed to automatically position an ArcRotateCamera when its target is set to a mesh. It is also useful if you want to prevent the camera to go under a virtual horizontal plane.

This behavior can be configured with the following properties:

  • mode: The behavior can be configured to:
    • BABYLON.FramingBehavior.IgnoreBoundsSizeMode: The camera can move all the way towards the mesh
    • BABYLON.FramingBehavior.FitFrustumSidesMode: The camera is not allowed to zoom closer to the mesh than the point at which the adjusted bounding sphere touches the frustum sides
  • radiusScale: Define the scale applied to the radius (1 by default)
  • positionY: Define the Y offset of the primary mesh from the camera's focus (0 by default)
  • defaultElevation: Define the angle above/below the horizontal plane to return to when the return to default elevation idle behaviour is triggered, in radians (0.3 by default)
  • elevationReturnTime: Define the time (in milliseconds) taken to return to the default beta position (1500 by default). Negative value indicates camera should not return to default
  • elevationReturnWaitTime: Define the delay (in milliseconds) taken before the camera returns to the default beta position (1000 by default)
  • zoomStopsAnimation: Define if user zooming should stop animation
  • framingTime: Define the transition time when framing the mesh, in milliseconds (1500 by default)

You can easily turn on this behavior on an ArcRotateCamera with the following code:

camera.useFramingBehavior = true;

You can find a live demo here: https://www.babylonjs-playground.com/#6FBD14#2 -