XRIK

Noting up-front: XRIK is a preview package and it has been over 100 days since XRIK has been updated by Unity. Unity claims they are still actively developing it. So far the primary feedback has been that it was designed in a way that makes it uncharacteristically difficult to extend.
It is likely to change and possibly significantly.

Main Components of XRIK:

• XR Rig (wraps up user-space in a movable room-scale rig)

• Controllers (InputDevice or XRNode)

• Interaction via:

  • Interactors

  • Interactables

• Interaction States

  • Hover (direct or ray-interaction is currently valid: similar to mouse-over event in UI)

  • Selected (action following a hover, indicating user intent: grab, trigger teleport, make active selection)

  • Activated (a secondary state of selected item. shoot a held gun, flashlight switch, etc)

• Locomotion

  • typically triggered via Interaction system (usually by ray interactors)

  • managed by a locomotion system, which is fed requests by one or more locomotion providers

    • teleport and snap-turn locomotion providers are included

    • custom provider can be made to perform smooth locomotion or alternatives

The primary concept in the XRTK is the relation between Interactors and Interactables

The framework takes care of a lot of other things (namely easing multiplatform development), but the central Interaction metaphor is broken down into those two things: Interactor and Interactable.

Interactables

Interactables are interactive "things in the world"
They may react to the users hands via Interactors on their hands or in the world
Your hands are interactors, the raycast for teleporting is an interactor

Movement type:

• • • Velocity Tracking vs Kinematic:

      • Kinematic Directly controls Interactable

      • Velocity tracking considers Interactables physics constraints

        • hinged doors, drawers, switches, etc

Links and References

How Drifter Optimized Robo Recall for Quest
Profiling and Optimization in UE4
Optimizing Performance across Oculus Mobile (Unity)
Oculus guidelines: Configure Unity for Quest

Quest Optimization Tips

• Use ASTC texture compression

• Vulkan still problematic

• REDUCE DRAW CALLS

  • batch meshes

  • atlased textures (2k atlas texture)

  • limit number of materials

  • "more efficient to push a lot of vertices in few draw calls, than a few vertices in many draw calls"

• Light & Shadows

  • Pixel lights: no more than 1, preferably 0

    • limit real-time/dynamic lights

    • limit what those lights effect

  • hard shadows ok, no shadows preferred

    • use blob shadow mesh for characters

  • Baked lighting

    • lightmap at 4k has worked well

    • non-directional

    • light probes are efficient and mobile friendly

  • Faked lighting

    • "volumetric lighting" on geometry

      • possible Oculus dome lightbeam mesh? Manipulate angle via blendshapes?

    • particles provide atmosphere

Unity Specific Quest Optimizations

Stereo Rendering Method: Single Pass (CPU gains via fewer draw calls)

Quest - Profiling performance on-device

need Android ADB bridge