Add the support for downloading an image from a given url in keyvaluetags of the Trackable

README.md

@@ -24,15 +24,15 @@ This wrapper for the World Analysis relies on the ARFoundation (version 5.1.x) U
 
 Image markers are supported on both iOS and Android platforms through ARKit and ARCore.
 
-The name of the Trackable in the World Storage must correspond to the name of a file (jpg or png) placed in the Unity persistent data path of the application on the user device.
+The name of the Trackable in the World Storage must correspond to the name of a file (jpg or png) placed in the Unity persistent data path of the application on the user device. The variable keyvalueTags of the Trackable can also contain a parameter with the "url" key providing a link to download the image.
 
 More information about ARFoundation Image Tracking can be found here: https://docs.unity3d.com/Packages/com.unity.xr.arfoundation@5.1/manual/index.html
 
 ### Mesh Trackables ###
 
-Mesh trackable are supported on iOS through ARKit.
+Mesh trackables are supported on iOS through ARKit.
 
-ARKit can track meshes that are defined in the .arobject format. Such an object can be scanned with the sample application provided here : https://developer.apple.com/documentation/arkit/arkit_in_ios/content_anchors/scanning_and_detecting_3d_objects
+ARKit can track meshes that are defined in the .arobject format. Such an object can be scanned with the sample application provided here: https://developer.apple.com/documentation/arkit/arkit_in_ios/content_anchors/scanning_and_detecting_3d_objects
 
 Unity serializes .arobject into ARKitReferenceObjectEntry in the editor. ARKitReferenceObjectEntry cannot then be imported at runtime from a .arobjject file. Dynamic loading is not supported yet.
 

Runtime/Scripts/WorldAnalysisARFoundationHelper.cs

+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+using System.Threading.Tasks; 
+using System.Net ;
+using System.IO ;
+
+public class WorldAnalysisARFoundationHelper 
+{
+    /// <summary>
+    /// Downaload file http
+    /// </summary>
+    /// <param name="toLoad">load url</param>
+    /// <returns>key and value with local path and file name with extension</returns>
+    public static async Task<KeyValuePair<string, string> > DownloadFileHTTP(string toLoad)
+    {
+        string filePath = "";
+        string fileName = "";
+        #if UNITY_EDITOR
+            string folder = Application.streamingAssetsPath;
+        #else 
+            string folder = Application.persistentDataPath;
+        #endif
+        
+        using (var client = new WebClient())
+        {
+            await client.DownloadFileTaskAsync(toLoad, folder + "/Temp.data");
+            string header_contentDisposition = client.ResponseHeaders["content-disposition"];
+            if (header_contentDisposition == null)
+            {
+                string[] splittedLink = toLoad.Split('/');
+                fileName = splittedLink[splittedLink.Length - 1];
+            }
+            else
+            {
+                fileName = new System.Net.Mime.ContentDisposition(header_contentDisposition).FileName;
+            }
+            filePath = folder + "/" + fileName;
+            if (File.Exists(filePath))
+            {
+                File.Delete(filePath);
+            }
+            File.Move(folder + "/Temp.data", filePath);
+        }
+        return new KeyValuePair<string, string>(filePath , fileName);
+    }
+}

Runtime/Scripts/WorldAnalysisARFoundationHelper.cs.meta

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Runtime/Scripts/WorldAnalysisARFoundationModuleImage.cs

@@ -68,7 +68,20 @@ public class WorldAnalysisARFoundationModuleImage : WorldAnalysisARFoundationMod
         {
             return false;
         }
-        bool resul = AddImageToLibrary(trackable.Name, (float)trackable.TrackableSize[0]);
+
+        // Check if an image url is provided
+        string url = "" ;
+        if (trackable.KeyvalueTags.ContainsKey("url"))
+        {
+            foreach(string s in trackable.KeyvalueTags["url"])
+            {
+                // first one
+                url = s ;
+                break ;
+            }
+        }
+
+        bool resul = AddImageToLibrary(trackable.Name, url, (float)trackable.TrackableSize[0]);
         if (resul)
         {
             m_uuidToName[trackable.UUID] = trackable.Name;
@@ -133,9 +146,10 @@ public class WorldAnalysisARFoundationModuleImage : WorldAnalysisARFoundationMod
     /// Add a new image to the arfoundation library
     /// </summary>
     /// <param name="fileName">file name</param>
+    /// </param name="url"> potential url</param>
     /// <param name="imageWidthInMeters">image width in meters</param>
-    /// <returns></returns>
-    protected bool AddImageToLibrary(string fileName, float imageWidthInMeters)
+    /// <returns>image found or not</returns>
+    protected bool AddImageToLibrary(string fileName, string url, float imageWidthInMeters)
     {
         // check if image is in the library
         if (m_trackedImageInLibrary.Contains(fileName))
@@ -150,18 +164,50 @@ public class WorldAnalysisARFoundationModuleImage : WorldAnalysisARFoundationMod
 #endif
 
         bool found = CheckImageExist(ref imagePath); // try to find in jpg or png
-        if (!found)
+        if (!found && url.Length == 0)
         {
             Debug.LogWarning("Try to Track Image " + fileName + "  but file not found");
             return false; 
         }
-        
-        //Load texture and add it to arfoundation library
+
+        if (!found)
+        {
+            // Here we don't check if url exists and still return true: could be improve
+            LoadTextureFromURL(url, fileName, imageWidthInMeters);
+        }
+        else 
+        {
+            //Load texture and add it to arfoundation library
+            LoadTextureFromMemory(imagePath, fileName, imageWidthInMeters);
+        }
+        return true;
+    }
+
+    /// <summary>
+    /// Add a new image from local memory to the arfoundation library
+    /// </summary>
+    /// </param name="imagePath"> local image path</param>
+    /// <param name="fileName">file name</param>
+    /// <param name="imageWidthInMeters">image width in meters</param>
+    private void LoadTextureFromMemory(string imagePath, string fileName, float imageWidthInMeters)
+    {
         var rawData = File.ReadAllBytes(imagePath);
         Texture2D tex = new Texture2D(2, 2);
         tex.LoadImage(rawData);
         AddTextureToLibrary(tex, fileName, imageWidthInMeters);
-        return true;
+    }
+
+    /// <summary>
+    /// Add a new image from a given url to the arfoundation library
+    /// </summary>
+    /// </param name="url"> url to the image to download</param>
+    /// <param name="fileName">file name</param>
+    /// <param name="imageWidthInMeters">image width in meters</param>
+    public async void LoadTextureFromURL(string url, string fileName, float imageWidthInMeters)
+    {
+        Debug.Log("Download image from url "+ url);
+        KeyValuePair<string , string> downloaded = await WorldAnalysisARFoundationHelper.DownloadFileHTTP(url);
+        LoadTextureFromMemory(downloaded.Key, fileName, imageWidthInMeters);
     }
 
     /// <summary>