hz-unity-meta-core-sdk

Meta XR Core SDK (com.meta.xr.sdk.core)

The Meta XR Core SDK is the foundational Unity package for developing VR and MR applications targeting Meta Quest headsets. It provides the core XR rig, device management, input handling, and access to platform features like passthrough, hand tracking, spatial anchors, and scene understanding.

Package: com.meta.xr.sdk.core

Finding the SDK Source

The package com.meta.xr.sdk.core may be located in different places depending on the project setup:

• Library/PackageCache/com.meta.xr.sdk.core@<hash>/ (cached from registry)
• Packages/com.meta.xr.sdk.core/ (local package reference)
• A custom on-disk path (embedded or local folder)

Before searching for SDK source, first locate the package root by searching for a known file by filename pattern:

**/com.meta.xr.sdk.core*/Scripts/OVRManager.cs

Then use the resolved parent path for all subsequent search operations.

CRITICAL: After Any OVRProjectConfig or OVRManager Feature Change

Any time you modify OVRProjectConfig or OVRManager feature settings (hand tracking, passthrough, boundaryless, target devices, etc.), you MUST call GenerateOrUpdateAndroidManifest() and verify the result. See references/android-manifest.md for the full workflow.

Quick Reference

Component	Purpose
OVRCameraRig	Primary XR rig prefab replacing Unity's Main Camera
OVRManager	Singleton managing device state, features, and configuration
OVRInput	Unified API for controller input and tracking
OVROverlay	Compositor layers for sharper text, UI, and video
OVRPassthroughLayer	Enables passthrough visualization
OVRSpatialAnchor	World-locked spatial anchors
OVRBoundary	Guardian boundary system access
OVRProjectSetup	Project Setup Tool for configuration tasks

OVRCameraRig: The Primary XR Rig

The OVRCameraRig prefab is the primary GameObject to add to create a VR/MR scene. It replaces Unity's conventional Main Camera and provides:

• Stereo rendering for left/right eyes
• Head and positional tracking via the TrackingSpace hierarchy
• Anchors for eyes (CenterEyeAnchor, LeftEyeAnchor, RightEyeAnchor)
• Anchors for hands/controllers (LeftHandAnchor, RightHandAnchor)

Hierarchy Structure

The OVRCameraRig hierarchy includes eye anchors, hand/controller anchors, and multimodal anchors. To see the current structure, inspect the OVRCameraRig prefab or instantiate it in a scene and examine the TrackingSpace children.

Adding OVRCameraRig to a Scene

When working with a scene that needs XR support:

1. Check if OVRCameraRig exists in the current scene
2. If NOT found, the agent should:
   • Option A: Ask the user which scene contains the OVRCameraRig (it is part of the OVRCameraRig prefab instance)
   • Option B: Open a scene where the agent knows the OVRCameraRig exists
   • Option C: Ask the user if they want to add the OVRCameraRig prefab to the current scene
3. When adding OVRCameraRig, follow the setup steps in references/ovr-camera-rig.md.

OVRManager: Feature Configuration

OVRManager (OVRManager.cs) is the main interface to VR hardware. It is a singleton attached to the OVRCameraRig prefab that exposes the Meta XR SDK to Unity. It controls:

• Target Devices - Which Quest headsets to target
• Performance & Quality - MSAA, adaptive resolution, dynamic resolution
• Tracking - Tracking origin type (Eye Level, Floor Level, Stage, Stationary)
• Display - Color gamut settings
• Quest Features - Hand tracking, passthrough, keyboard, focus awareness, security, experimental features
• Mixed Reality Capture - Real-world compositing

Analyzing OVRManager for Features

To understand what features are available and how they're configured, analyze the OVRManager component on the OVRCameraRig in the scene. The OVRManager Inspector exposes all configurable XR features grouped into sections.

For the full settings reference (tracking origin, passthrough, boundary, hand tracking on OVRProjectConfig, etc.), see references/ovr-manager.md.

OVRProjectSetup (UPST): Listing and Fixing Project Issues

The Unity Project Setup Tool (UPST) (OVRProjectSetup) is a Unity Editor extension that validates project configuration for Meta Quest. It maintains a registry of Configuration Tasks — each task checks a specific setting and reports whether it is satisfied or outstanding.

Primary use: list all outstanding issues for the current platform, then fix them.

• List issues — Query all tasks, filter by platform/validity, and report those where IsDone is false. Each issue has a level (Required, Recommended, Optional), a group (Compatibility, Rendering, Features, etc.), and a fix type (Auto-fix or Manual).
• Fix issues — Use FixAllAsync(BuildTargetGroup) to auto-fix all fixable issues, or invoke individual FixAction delegates directly.

UPST can be driven programmatically via Unity MCP using reflection (see references/project-setup-tool.md for the full API, task registry access, property reading, and fix invocation patterns).

Access via UI: Meta > Tools > Project Setup Tool.

CRITICAL: AndroidManifest Update

NEVER directly edit AndroidManifest.xml for features managed by OVRProjectConfig. See references/android-manifest.md for the full manifest update workflow and rules.

Core Features

Passthrough (Mixed Reality)

Passthrough provides real-time visualization of the physical world inside the headset, enabling mixed reality experiences. See references/passthrough.md for setup steps and configuration.

Hand Tracking

Hand tracking enables natural hand interaction without controllers. See references/hand-tracking.md for setup and configuration.

Spatial Anchors

Spatial anchors anchor virtual content to real-world locations that persist across sessions.

For spatial anchors details, see references/spatial-anchors.md.

Scene API

Scene provides access to the user's physical environment model (walls, floor, furniture) for scene-aware MR experiences.

For Scene API details, see references/scene-api.md.

Boundaryless Mode

Boundaryless mode disables the Guardian boundary for MR experiences where the physical world is visible.

For boundaryless setup, see references/boundaryless.md.

Compositor Layers (OVROverlay)

OVROverlay renders textures directly via the VR compositor, bypassing eye buffer resampling for sharper text, UI, and video. Supports up to 15 overlay layers per scene with quad, cylinder, cubemap, equirect, and fisheye shapes.

For compositor layer details, see references/ovr-overlay.md.

Controller Input (OVRInput)

OVRInput provides unified access to controller buttons, triggers, thumbsticks, and tracking.

For controller input details, see references/controller-input.md.

Project Setup Workflow

For the full project setup workflow (install SDK, set build platform, configure XR provider, add OVRCameraRig, configure OVRManager, generate AndroidManifest), see references/project-setup-workflow.md.

Documentation Links

All documentation references point to the official Meta developer docs at developers.meta.com:

• Meta XR Core SDK Overview
• OVRCameraRig Configuration
• Project Setup Tool
• Android Manifest Generation
• Passthrough API
• Hand Tracking Overview
• Spatial Anchors Overview
• Scene Overview
• Compositor Layers (OVROverlay)
• Controller Input
• Project Configuration

Calling SDK Methods via Unity MCP

SDK classes (e.g. OVRManifestPreprocessor, OVRProjectSetup) live in assemblies that are not directly referenceable from Unity MCP compiled scripts. You must use runtime reflection to call them. The Unity MCP compilation environment also has specific quirks that will cause silent crashes if not followed.

Rules

1. Never add using System.Reflection; — it causes UNEXPECTED_ERROR crashes in the MCP framework. Fully qualify reflection types instead (e.g. System.Reflection.TargetInvocationException).
2. Never use BindingFlags overloads of GetMethod / GetProperty — they also trigger MCP crashes. Use the parameterless GetMethod("MethodName") overload (finds public methods by default).
3. Always pass silentMode: true (or equivalent) for any method that may call EditorUtility.DisplayDialog — dialogs block indefinitely in MCP context.
4. Always catch System.Reflection.TargetInvocationException and log InnerException — reflection wraps the real error.

Template

using UnityEngine;
using UnityEditor;

internal class CommandScript : IRunCommand
{
    public void Execute(ExecutionResult result)
    {
        // 1. Find the type by name across all loaded assemblies
        System.Type t = null;
        foreach (var asm in System.AppDomain.CurrentDomain.GetAssemblies())
        {
            try { t = asm.GetType("CLASS_NAME_HERE"); } catch { }
            if (t != null) break;
        }
        if (t == null) { result.LogError("Type CLASS_NAME_HERE not found."); return; }

        // 2. Get the method (parameterless overload only — no BindingFlags)
        var m = t.GetMethod("METHOD_NAME_HERE");
        if (m == null) { result.LogError("Method METHOD_NAME_HERE not found."); return; }

        // 3. Invoke with error handling
        try
        {
            m.Invoke(null, new object[] { /* args */ });
            result.Log("Done.");
        }
        catch (System.Reflection.TargetInvocationException tie)
        {
            result.LogError("Error: " + tie.InnerException);
        }
    }
}

Replace CLASS_NAME_HERE, METHOD_NAME_HERE, and the args array as needed. For instance methods, pass the target object instead of null.

Using metavr Tools for Latest Docs

If the metavr MCP server is available, use the mcp__metavr__meta_docs_search and mcp__metavr__meta_docs_get_page tools to verify current API details, as Meta SDK documentation updates frequently. Use mcp__metavr__search_api_reference with engine='unity' to look up exact method signatures for OVRManager, OVRCameraRig, OVRInput, and other classes.