Touch Interactions

The Telerik XR Core package provides a mechanism for handling close finger interactions through its ITouchSurface interface. This interface is used in the Telerik XR Interactions package to detect the components that interact with fingers when hand tracking is available.

ITouchSurface Interface

This interface is used to calculate the closest point and surface orientation when interacting with a touch surface. It is used to detect the surfaces that are available for touch interactions and to perform the needed calculations during the close distance interactions. You must implement the following methods:

• ClosestPoint—receives a point in space as an argument and returns the closest point from the touch surface.
• SurfaceDirection—receives a point in space as an argument and returns the surface direction at the closest surface point.

TouchSurfaceCanvas Class

This class implements the ITouchSurface interface allowing finger interactions with Canvas UI. TouchSurfaceCanvas must be attached to a Canvas element with RectTransform and BoxCollider components and is responsible for updating the collider when the RectTransform dimensions are changed.

Touch Surface Canvas Prefab

For easier setup, you may drag and drop the Touch Surface Canvas prefab which is located in the XR Core package Prefabs folder. This prefab has a predefined structure with necessary colliders and components and you only need to adjust its RectTransform dimensions based on the touch surface size and position that you want to create in your scene.