xr-development

XR Development in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> Related skills: 3d-essentials for 3D rendering and environment, physics-system for 3D physics interactions, input-handling for non-XR input patterns, export-pipeline for platform exports.

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1. XR Setup

Enabling OpenXR

1. Project Settings → Plugins → Enable: OpenXR (or OpenXR Plugin depending on version)
2. Project Settings → XR → OpenXR → Enabled → true
3. Project Settings → XR → Shaders → Enabled → true (for XR shader support)
4. Rendering:

• Use Forward+ or Mobile renderer (Compatibility also works for simpler scenes)
• Set Project Settings → Display → Window → VSync Mode to Disabled (the XR runtime controls frame timing)

Core Scene Structure

Main (Node3D)
├── XROrigin3D                    ← Player's physical space origin
│   ├── XRCamera3D                ← Head-mounted display
│   ├── XRController3D (left)     ← Left controller
│   │   └── LeftHandModel (MeshInstance3D or hand tracking)
│   ├── XRController3D (right)    ← Right controller
│   │   └── RightHandModel
│   └── (XRBodyTracker via XRServer — optional full body tracking)
├── WorldEnvironment
└── GameWorld (Node3D)
    └── ... level geometry

Starting XR Session

extends Node3D

func _ready() -> void:
    var xr_interface: XRInterface = XRServer.find_interface("OpenXR")
    if xr_interface and xr_interface.is_initialized():
        get_viewport().use_xr = true
    else:
        push_error("OpenXR not available")

public partial class XRMain : Node3D
{
    public override void _Ready()
    {
        var xrInterface = XRServer.FindInterface("OpenXR");
        if (xrInterface != null && xrInterface.IsInitialized())
            GetViewport().UseXr = true;
        else
            GD.PushError("OpenXR not available");
    }
}

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2. Controllers and Input

XRController3D nodes (one per hand, child of XROrigin3D) expose buttons via the OpenXR action map. Common buttons: trigger (select_button), grip (grip_button), thumbstick (primary_axis Vector2). Apply thumbstick locomotion velocity to XROrigin3D (not the camera).

> See [references/controllers-and-input.md](references/controllers-and-input.md) for full XRController3D wiring, OpenXR button reference, and thumbstick locomotion recipe.

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3. Hand Tracking

When the headset supports hand tracking (Quest 2+, Vision Pro), XRController3D nodes can be configured to track hand joints. Sample finger positions for gesture detection, or bind to standard select / grip events when the user pinches.

> See [references/hand-tracking.md](references/hand-tracking.md) for hand-tracking node setup, joint sampling, and gesture-driven interactions.

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4. Grabbing Objects

Standard pattern: an Area3D on the controller detects nearby RigidBody3D objects; on grip-press, parent the body to the controller and freeze it; on grip-release, restore the parent and apply the controller's velocity to launch.

> See [references/grabbing-objects.md](references/grabbing-objects.md) for the full physics-based grabbing implementation (GDScript + C#).

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5. XR UI Interaction

For UI in VR, render a Control tree to a SubViewport, map its texture onto a Quad mesh placed in 3D space. Pointer: a RayCast3D from the controller hits the quad, the hit position is converted back to 2D viewport coords, an InputEventMouseMotion is forwarded into the SubViewport.

> See [references/xr-ui.md](references/xr-ui.md) for the SubViewport-on-quad recipe and pointer/ray interaction.

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6. Passthrough (Mixed Reality)

For headsets that support it (Quest 2+, Vision Pro), set OpenXRInterface.environment_blend_mode = XR_ENVIRONMENT_BLEND_MODE_ALPHA_BLEND and clear the WorldEnvironment background to transparent. The user sees the real world with virtual content composited on top.

> See [references/passthrough.md](references/passthrough.md) for the full enabling steps and Quest-specific notes.

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7. Meta Quest Export

Setup

1. Install Android Build Template: Project → Install Android Build Template
2. Install OpenXR Vendors plugin: Project → Project Settings → Plugins → Enable Godot OpenXR Vendors (or install from AssetLib)
3. Export → Add → Android
4. In the Android export preset:

• XR Features → XR Mode → OpenXR
• XR Features → Hand Tracking → Optional or Required
• XR Features → Passthrough → Optional (if needed)
• Architectures → arm64 → enabled (Quest is ARM)

1. Set minimum API level to 29+

Performance Settings for Quest

| Setting | Recommended Value |

|---------|-------------------|

| Renderer | Mobile |

| MSAA | 2x or 4x (VR needs antialiasing) |

| Texture Compression | ETC2/ASTC |

| Target FPS | 72 (Quest 2) or 90 (Quest 3) |

> Critical: VR must maintain consistent frame rate. Dropped frames cause nausea. Profile aggressively and keep draw calls low.

> ⚠️ Changed in Godot 4.7: New project settings xr/openxr/foveation_eye_tracked and xr/openxr/foveation_with_subsampled_images both default to true — when the foveation level is not "Disabled", eye-tracked foveation is used where the headset supports it, and subsampled images are used on Vulkan for a bigger foveation win. Subsampled images are incompatible with many screen-space features (e.g., FXAA, glow); if any are enabled, subsampled images are automatically disabled with a log warning. Set either setting to false to opt out. See GH-117868.

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8. Godot 4.5+ XR Features

Godot 4.5 adds a D3D12 OpenXR backend on Windows (Quest Link / SteamVR alternative to Vulkan), foveated rendering on the Mobile Vulkan renderer, Application SpaceWarp frame synthesis for Quest/Pico, OpenXR Render Models for platform-native controller meshes, and native visionOS export via the Apple Embedded preset. All are enabled through Project Settings or the Godot OpenXR Vendors plugin — no engine-level code changes.

> See [references/godot-4-5-features.md](references/godot-4-5-features.md) for enabling steps, GDScript + C# render-model snippets, and per-feature caveats.

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9. Godot 4.6+ XR Features

OpenXR 1.1 Support (Godot 4.6+)

Godot 4.6 ships with native OpenXR 1.1 runtime support. Devices and runtimes that implement OpenXR 1.1 automatically unlock 1.1 features (improved compositor layers, updated interaction profiles, etc.) without any project-level change. No API change is required — the engine negotiates the spec version with the runtime at startup.

> Note: OpenXR 1.1 was introduced in Godot 4.6 (beta as of this writing). API behaviour may evolve before the stable release — see https://godotengine.org/article/dev-snapshot-godot-4-6-beta-1/ for current details.

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Spatial Entities — Anchors, Plane Tracking, Marker Tracking (Godot 4.6+)

Godot 4.6 stabilises the XR Spatial Entities extension, enabling:

• Spatial anchors — persist virtual object positions across sessions (XRSpatialAnchor)
• Plane detection — detect floor, wall, and ceiling surfaces from the environment scan
• Marker tracking — track QR codes or image markers in the scene

Basic spatial anchor usage:

# Requires: OpenXR Spatial Entities extension enabled in the vendor plugin
# XRSpatialAnchor is a Node3D placed in your scene that the runtime keeps locked
# to a real-world location.

extends Node3D

@export var anchor_scene: PackedScene  # Scene containing XRSpatialAnchor

func place_anchor_at(world_position: Vector3) -> void:
    var anchor: XRSpatialAnchor = XRSpatialAnchor.new()
    anchor.position = world_position
    add_child(anchor)
    # The XR runtime takes over tracking once the node is added to the scene tree.
    # Persist the anchor UUID to restore it on next launch (platform-specific API).

// Requires: OpenXR Spatial Entities extension enabled in the vendor plugin
public partial class SpatialAnchorManager : Node3D
{
    public void PlaceAnchorAt(Vector3 worldPosition)
    {
        var anchor = new XRSpatialAnchor();
        anchor.Position = worldPosition;
        AddChild(anchor);
        // The XR runtime takes over tracking once added to the scene tree.
        // Persist anchor UUID via platform-specific API for cross-session recall.
    }
}

> Note: XRSpatialAnchor, plane tracking, and marker tracking APIs were introduced in Godot 4.6 (beta as of this writing). The full API surface — especially persistence, query callbacks, and plane/marker node types — may change before the stable release. See https://godotengine.org/article/dev-snapshot-godot-4-6-beta-1/ for current signatures and the Godot OpenXR Vendors plugin for platform-specific spatial entity setup.

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10. Godot 4.7+ XR Features

User Presence Detection (Godot 4.7+)

OpenXRInterface exposes the OpenXR user presence extension: the user_presence_changed(is_user_present: bool) signal fires when the user puts on or removes the headset, is_user_presence_supported() reports whether the extension is supported and enabled, and is_user_present() polls the current state (both only return valid values after OpenXR is initialized). Typical use: pause the game and mute audio when the headset comes off.

> Note: The signal is not emitted during application startup or shutdown — assume user presence is gained on startup and lost on shutdown.

func _ready() -> void:
    var xr_interface: OpenXRInterface = XRServer.find_interface("OpenXR")
    if xr_interface and xr_interface.is_user_presence_supported():
        xr_interface.user_presence_changed.connect(_on_user_presence_changed)

func _on_user_presence_changed(is_user_present: bool) -> void:
    get_tree().paused = not is_user_present

public override void _Ready()
{
    var xrInterface = XRServer.FindInterface("OpenXR") as OpenXRInterface;
    if (xrInterface != null && xrInterface.IsUserPresenceSupported())
        xrInterface.UserPresenceChanged += OnUserPresenceChanged;
}

private void OnUserPresenceChanged(bool isUserPresent)
{
    GetTree().Paused = !isUserPresent;
}

Composition Layer Eye Visibility (Godot 4.7+)

OpenXRCompositionLayer gains eye_visibility (EyeVisibility enum: EYE_VISIBILITY_BOTH = 0 default, EYE_VISIBILITY_LEFT = 1, EYE_VISIBILITY_RIGHT = 2) — the eye(s) the composition layer is visible to. Renders a quad/cylinder/equirect layer to one eye only, e.g. for per-eye calibration screens or stereo content authored per eye.

$OpenXRCompositionLayerQuad.eye_visibility = OpenXRCompositionLayer.EYE_VISIBILITY_LEFT

GetNode<OpenXRCompositionLayerQuad>("OpenXRCompositionLayerQuad").EyeVisibility =
    OpenXRCompositionLayer.EyeVisibilityEnum.Left;

> Note: Not all composition layer types or runtimes support restricting visibility to a single eye.

Spatial Anchor Extensibility (Godot 4.7+)

OpenXRSpatialAnchorCapability.create_new_anchor() gains an optional next parameter — full signature: create_new_anchor(transform: Transform3D, spatial_context: RID = RID(), next: OpenXRStructureBase = null) -> OpenXRAnchorTracker. next must be a valid next object for the XrSpatialAnchorCreateInfoEXT chain, letting vendor-specific create-info structs be appended when creating an anchor. Existing calls are unaffected (compatible change, GH-118128).

> Note: OpenXRSpatialAnchorCapability is still marked experimental — the class may change in future versions. For typical anchor placement, keep using the node-based workflow from Section 9.

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11. Common Pitfalls

| Symptom | Cause | Fix |

|---------|-------|-----|

| Black screen in headset | use_xr = true not set on viewport | Set in _ready() after checking XR interface |

| Controller input not firing | Wrong signal name for the platform | Check OpenXR action map bindings in Project Settings |

| Objects scale wrong in VR | Scene not built at real-world scale | Use 1 unit = 1 meter throughout the scene |

| Motion sickness from locomotion | Smooth rotation | Use snap turning (30° increments) or add a vignette during movement |

| UI unreadable in VR | Panel too far away or too small | Place UI at 1–2m distance, use SubViewport at 1024+ resolution |

| Hand tracking jittery | Raw joint data used directly | Apply smoothing (lerp toward new position each frame) |

| Export fails on Quest | Missing Android build template or wrong architecture | Install Android Build Template; enable arm64; set API level 29+ |

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12. Implementation Checklist

• [ ] OpenXR is enabled in Project Settings
• [ ] Scene uses XROrigin3D → XRCamera3D + XRController3D hierarchy
• [ ] XR session is started with get_viewport().use_xr = true after interface check
• [ ] World is built at 1 unit = 1 meter scale
• [ ] Controller input uses OpenXR action names (trigger_click, grip_click, etc.)
• [ ] Fallback exists for hand tracking → controller tracking
• [ ] UI panels use SubViewport rendered on a 3D mesh
• [ ] Locomotion includes comfort options (snap turn, vignette)
• [ ] VSync is disabled (XR runtime handles frame timing)
• [ ] Quest export uses Mobile renderer, arm64 architecture, API level 29+
• [ ] On Windows Quest Link / SteamVR builds, consider D3D12 backend if Vulkan drivers are problematic (Godot 4.5+)
• [ ] Foveated rendering enabled via OpenXR Vendors plugin for standalone Quest/Pico targets (Godot 4.5+)
• [ ] Application SpaceWarp evaluated for performance budget on Meta Quest / Pico targets (Godot 4.5+)
• [ ] OpenXR Render Models used for controller visuals instead of bundled meshes where supported (Godot 4.5+)
• [ ] visionOS export uses the Apple Embedded preset with visionOS SDK target (Godot 4.5+)
• [ ] Spatial anchors use XRSpatialAnchor and vendor plugin spatial entities extension (Godot 4.6+)
• [ ] Headset on/off handled via OpenXRInterface.user_presence_changed — pause/mute when the user is away (Godot 4.7+)
• [ ] Foveation defaults reviewed — xr/openxr/foveation_eye_tracked and xr/openxr/foveation_with_subsampled_images are on by default; disable subsampled images if you rely on FXAA/glow (Godot 4.7+)