Add sample showing ARWorldMap support

Packages/manifest.json

 {
-  "dependencies": {
-    "com.unity.xr.arcore": "1.0.0-preview.20",
-    "com.unity.xr.arfoundation": "1.0.0-preview.19",
-    "com.unity.xr.arkit": "1.0.0-preview.16"
-  }
-}
+    "dependencies": {
+      "com.unity.xr.arcore": "1.0.0-preview.23",
+      "com.unity.xr.arfoundation": "1.0.0-preview.20",
+      "com.unity.xr.arkit": "1.0.0-preview.17"
+    },
+    "registry": "https://staging-packages.unity.com"
+  }

Assets/Scenes/ARWorldMap.unity.meta

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Assets/Scripts/ARWorldMapController.cs

+using System.Collections;
+using System.Collections.Generic;
+using System.IO;
+using Unity.Collections;
+using UnityEngine;
+using UnityEngine.UI;
+using UnityEngine.XR.ARFoundation;
+#if UNITY_IOS
+using UnityEngine.XR.ARKit;
+#endif
+
+public class ARWorldMapController : MonoBehaviour
+{
+    [SerializeField]
+    ARSession m_ARSession;
+
+    [SerializeField]
+    Text m_ErrorText;
+
+    [SerializeField]
+    Button m_SaveButton;
+
+    [SerializeField]
+    Button m_LoadButton;
+
+    [SerializeField]
+    Text m_LogText;
+
+    [SerializeField]
+    Text m_MappingStatus;
+
+    public void OnSaveButton()
+    {
+#if UNITY_IOS
+        StartCoroutine(Save());
+#endif
+    }
+
+    public void OnLoadButton()
+    {
+#if UNITY_IOS
+        StartCoroutine(Load());
+#endif
+    }
+
+    public void OnResetButton()
+    {
+        m_ARSession.Reset();
+    }
+
+#if UNITY_IOS
+    IEnumerator Save()
+    {
+        var sessionSubsystem = ARSubsystemManager.sessionSubsystem;
+        if (sessionSubsystem == null)
+        {
+            Log("No session subsystem available. Could not save.");
+            yield break;
+        }
+
+        var request = sessionSubsystem.GetARWorldMapAsync();
+
+        while (!request.status.IsDone())
+            yield return null;
+
+        if (request.status.IsError())
+        {
+            Log(string.Format("Session serialization failed with status {0}", request.status));
+            yield break;
+        }
+
+        var worldMap = request.GetWorldMap();
+        request.Dispose();
+
+        SaveAndDisposeWorldMap(worldMap);
+    }
+
+    IEnumerator Load()
+    {
+        var sessionSubsystem = ARSubsystemManager.sessionSubsystem;
+        if (sessionSubsystem == null)
+        {
+            Log("No session subsystem available. Could not load.");
+            yield break;
+        }
+
+        var file = File.Open(path, FileMode.Open);
+        if (file == null)
+        {
+            Log(string.Format("File {0} does not exist.", path));
+            yield break;
+        }
+
+        Log(string.Format("Reading {0}...", path));
+
+        int bytesPerFrame = 1024 * 10;
+        var bytesRemaining = file.Length;
+        var binaryReader = new BinaryReader(file);
+        var allBytes = new List<byte>();
+        while (bytesRemaining > 0)
+        {
+            var bytes = binaryReader.ReadBytes(bytesPerFrame);
+            allBytes.AddRange(bytes);
+            bytesRemaining -= bytesPerFrame;
+            yield return null;
+        }
+
+        var data = new NativeArray<byte>(allBytes.Count, Allocator.Temp);
+        data.CopyFrom(allBytes.ToArray());
+
+        Log(string.Format("Deserializing to ARWorldMap...", path));
+        ARWorldMap worldMap;
+        if (ARWorldMap.TryDeserialize(data, out worldMap))
+        data.Dispose();
+
+        if (worldMap.valid)
+        {
+            Log("Deserialized successfully.");
+        }
+        else
+        {
+            Debug.LogError("Data is not a valid ARWorldMap.");
+            yield break;
+        }
+
+        Log("Apply ARWorldMap to current session.");
+        sessionSubsystem.ApplyWorldMap(worldMap);
+    }
+
+    void SaveAndDisposeWorldMap(ARWorldMap worldMap)
+    {
+        Log("Serializing ARWorldMap to byte array...");
+        var data = worldMap.Serialize(Allocator.Temp);
+        Log(string.Format("ARWorldMap has {0} bytes.", data.Length));
+
+        var file = File.Open(path, FileMode.Create);
+        var writer = new BinaryWriter(file);
+        writer.Write(data.ToArray());
+        writer.Close();
+        data.Dispose();
+        worldMap.Dispose();
+        Log(string.Format("ARWorldMap written to {0}", path));
+    }
+#endif
+
+    string path
+    {
+        get
+        {
+            return Path.Combine(Application.persistentDataPath, "my_session.worldmap");
+        }
+    }
+
+    bool supported
+    {
+        get
+        {
+#if UNITY_IOS
+            var sessionSubsystem = ARSubsystemManager.sessionSubsystem;
+            if (sessionSubsystem != null)
+                return sessionSubsystem.WorldMapSupported();
+#endif
+            return false;
+        }
+    }
+
+    void Awake()
+    {
+        m_LogMessages = new List<string>();
+    }
+
+    void Log(string logMessage)
+    {
+        m_LogMessages.Add(logMessage);
+    }
+
+    void Update()
+    {
+        if (supported)
+        {
+            m_ErrorText.enabled = false;
+            m_SaveButton.enabled = true;
+            m_LoadButton.enabled = true;
+        }
+        else
+        {
+            m_ErrorText.enabled = true;
+            m_SaveButton.enabled = false;
+            m_LoadButton.enabled = false;
+        }
+
+        var sessionSubsystem = ARSubsystemManager.sessionSubsystem;
+        if (sessionSubsystem == null)
+            return;
+
+        var numLogsToShow = 20;
+        string msg = "";
+        for (int i = Mathf.Max(0, m_LogMessages.Count - numLogsToShow); i < m_LogMessages.Count; ++i)
+        {
+            msg += m_LogMessages[i];
+            msg += "\n";
+        }
+        m_LogText.text = msg;
+
+#if UNITY_IOS
+        m_MappingStatus.text = string.Format("Mapping Status: {0}", sessionSubsystem.GetWorldMappingStatus());
+#endif
+    }
+
+    List<string> m_LogMessages;
+}

Assets/Scripts/ARWorldMapController.cs.meta

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