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By design, the different locomotion interactors do not directly move the player around, but instead emit events requesting this action to be performed. This decouples the locomotor system so the way the user moves is not tied to how the user selects where to move. It also centralizes the movement instead of binding it to different interactors.

How do Locomotion Events work?

Locomotion events work by implementing broadcasters to send out the events and handlers to receive the events and perform some action accordingly.

LocomotionEvent has a Translation Type, a Rotation type , and a Pose indicating the parameters for this movement. The Pose.position indicates the Translation parameter and Pose.rotation the rotation parameter.

LocomotionEvent Type	Description	Example of use
Translation.Absolute	The pose.position indicates the absolute world position desired for the character’s feet.	Teleport to the mirror.
Translation.AbsoluteHead	The pose.position indicates the absolute world position desired for the character’s head.	Use this when the player head final positioning is more important than the character’s height, for example when seating in a virtual low chair.
Translation Relative	The pose.position indicates a Relative discrete movement.	Take a step backwards.
Translation Velocity	The pose.position indicates a velocity to be applied in that frame.	Move in the world forward direction at 1 m/s
Turning Absolute	The pose.rotation indicates the absolute world rotation desired for the character.	Face the mirror.
Turning Relative	The pose.rotation indicates a relative rotation around the player’s head.	Snap rotate 45 degrees to the left.
Teleport Velocity	The pose.rotation indicates an angular velocity to be applied in that frame.	Rotate at 90 degrees per second to the right

ILocomotionEventBroadcaster

ILocomotionEventBroadcaster is used for sending events. TurnerInteractor and TeleportInteractor implement it.

ILocomotionEventHandler

ILocomotionEventHandler is used for handling locomotion events. The component PlayerLocomotor implements it to listen to all incoming locomotion events and move the player at the end of the current frame when all updates have finished. This ensures no glitches happen and that the next frame is executed with all transforms correctly updated.

LocomotionEventsConnection

LocomotionEventsConnection collects several broadcasters at the interactors level and links them to one handler instead of directly pointing from a handler to several broadcasters.

TurnerEventBroadcaster

Turner Interactors do not provide locomotion turning events themselves. Instead they generate a state value (Disabled, Normal, Hover or Selected) and an axis 1D value (from -1 to 1). TurnerEventBroadcaster then reads these two values and generates the desired events. It supports two different turning modes: Snap and Smooth.

When using Snap turning, TurnerEventBroadcaster will fire a turning event once during select (either at the beginning or the end of the selection), which indicates that a Snap Turn Degrees instant rotation relative to the player should occur.

When using Smooth turning, TurnerEventBroadcaster will continuously fire events during select, indicating that the player should rotate at the rate specified in Smooth Turn Curve.

StepLocomotionBroadcaster

StepLocomotionBroadcaster generates relative translation events that request to move the player for a discrete amount in the ground plane.

SlideLocomotionBroadcaster

SlideLocomotionBroadcaster generates continuous translation events that requests to move the player at a specified velocity above the ground plane.

Learn more

To add locomotion interactions, see Create Locomotion Interactions.
To learn about the structure of interactions, see Interaction Architecture.
To learn about best practices when designing for locomotion, see the Locomotion Design Guide.

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