Tracked Device Graphic Raycaster component

The Tracked Device Graphic Raycaster component lets you use 3D tracked devices to highlight and select UI elements on a canvas.

Add a Tracked Device Graphic Raycaster component to the same GameObject containing the Canvas component.

Property	Description
Ignore Reversed Graphics	When enabled, raycasts ignore graphics facing away from the source of the raycast.
Check for 2D Occlusion	Enable if raycasts should be blocked by 2D objects occluding the canvas. Objects must have a collider to block the raycast. Enabling this option incurs a performance cost.
Check for 3D Occlusion	Enable if raycasts should be blocked by 3D objects occluding the canvas. Objects must have a collider to block the raycast. Enabling this option incurs a performance cost.
Blocking Mask	A LayerMask identifying the layers containing objects that are allowed to occlude the canvas.
Raycast Trigger Interaction	Specifies whether the ray cast should be blocked by trigger colliders when checking for 3D occlusion. Refer to QueryTriggerInteraction for more information.

Architecture notes

TrackedDeviceGraphicRaycaster uses two distinct result collections during a UI raycast pass:

• allRaycastResults (shared, aggregated output)

• allRaycastResults is the (RaycastResult)List (whose parameter in the Raycast function is named resultAppendList) provided by the Unity EventSystem during EventSystem.RaycastAll. This list is shared across all active raycasters for the current frame/event, and each raycaster is expected to append its own RaycastResult entries into it. The EventSystem later uses the aggregated results to determine hover, press, drag, click, and other UI event routing.

Due to allRaycastResults being shared and appended-to by multiple raycasters, its contents and ordering must not be assumed to belong to a single raycaster (e.g., allRaycastResults[0] may be a hit produced by a different raycaster).

• m_RaycasterLocalHitDataBuffer per-raycaster authoritative hit data

• m_RaycasterLocalHitDataBuffer is a per-instance working buffer containing RaycastHitData entries computed by this specific TrackedDeviceGraphicRaycaster. It is cleared and repopulated each cast (ray or spherecast) and used to sort candidate Graphic hits for this raycaster’s Canvas.

For poke interaction, m_RaycasterLocalHitDataBuffer[0] represents this raycaster’s top-ranked hit and is used as the authoritative target when evaluating poke state and selection via XRPokeLogic (passing the correct pokedTransform into MeetsRequirementsForSelectAction). This avoids relying on the shared allRaycastResults list for determining the “first hit,” which can be incorrect when multiple canvases/raycasters are active.