Add async callbacks to GLTFImportPluginContext

Runtime/Scripts/GLTFSceneImporter.cs

@@ -430,7 +430,7 @@ public void Dispose()
 				// TODO check where the right place is to call OnBeforeImport as early as possible
 				foreach (var plugin in Context.Plugins)
 				{
-					plugin.OnBeforeImport();
+					await plugin.OnBeforeImportAsync();
 				}
 
 				if (_options.ThrowOnLowMemory)
@@ -458,14 +458,14 @@ public void Dispose()
 				if (_gltfRoot == null)
 				{
 					foreach (var plugin in Context.Plugins)
-						plugin.OnBeforeImportRoot();
+						await plugin.OnBeforeImportRootAsync();
 					await LoadJson(_gltfFileName);
 					progressStatus.IsDownloaded = true;
 				}
 
 				foreach (var plugin in Context.Plugins)
 				{
-					plugin.OnAfterImportRoot(_gltfRoot);
+					await plugin.OnAfterImportRootAsync(_gltfRoot);
 				}
 
 				cancellationToken.ThrowIfCancellationRequested();
@@ -683,7 +683,7 @@ private void InitializeGltfTopLevelObject()
 			try
 			{
 				foreach (var plugin in Context.Plugins)
-					plugin.OnBeforeImportScene(scene);
+					await plugin.OnBeforeImportSceneAsync(scene);
 			}
 			catch (Exception e)
 			{
@@ -731,7 +731,7 @@ private void InitializeGltfTopLevelObject()
 			try
 			{
 				foreach (var plugin in Context.Plugins)
-					plugin.OnAfterImportScene(scene, sceneIndex, CreatedObject);
+					await plugin.OnAfterImportSceneAsync(scene, sceneIndex, CreatedObject);
 			}
 			catch (Exception e)
 			{
@@ -821,7 +821,7 @@ private async Task<GameObject> GetNode(int nodeId, CancellationToken cancellatio
 					try
 					{
 						foreach (var plugin in Context.Plugins)
-							plugin.OnAfterImportNode(node, nodeId, _assetCache.NodeCache[nodeId]);
+							await plugin.OnAfterImportNodeAsync(node, nodeId, _assetCache.NodeCache[nodeId]);
 					}
 					catch (Exception ex)
 					{

Runtime/Scripts/Plugins/Core/GltfImportPlugin.cs

@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using System.Threading.Tasks;
 using GLTF.Schema;
 using UnityEngine;
 
@@ -61,5 +62,51 @@ public virtual void OnAfterImport()
 		{
 
 		}
+
+#pragma warning disable CS1998 // Async method lacks 'await' operators and will run synchronously.
+		// These methods can be overridden if an importer needs to call async functions.
+		// These are provided for backwards compatibility and by default, will call the
+		// synchronous version.
+
+		public virtual async Task OnBeforeImportAsync()
+		{
+			OnBeforeImport();
+		}
+
+		public virtual async Task OnBeforeImportRootAsync()
+		{
+			OnBeforeImportRoot();
+		}
+
+		public virtual async Task OnAfterImportRootAsync(GLTFRoot gltfRoot)
+		{
+			OnAfterImportRoot(gltfRoot);
+		}
+
+		public virtual async Task OnBeforeImportSceneAsync(GLTFScene scene)
+		{
+			OnBeforeImportScene(scene);
+		}
+
+		public virtual async Task OnAfterImportNodeAsync(Node node, int nodeIndex, GameObject nodeObject)
+		{
+			OnAfterImportNode(node, nodeIndex, nodeObject);
+		}
+
+		public virtual async Task OnAfterImportMaterialAsync(GLTFMaterial material, int materialIndex, Material materialObject)
+		{
+			OnAfterImportMaterial(material, materialIndex, materialObject);
+		}
+
+		public virtual async Task OnAfterImportTextureAsync(GLTFTexture texture, int textureIndex, Texture textureObject)
+		{
+			OnAfterImportTexture(texture, textureIndex, textureObject);
+		}
+
+		public virtual async Task OnAfterImportSceneAsync(GLTFScene scene, int sceneIndex, GameObject sceneObject)
+		{
+			OnAfterImportScene(scene, sceneIndex, sceneObject);
+		}
+#pragma warning restore CS1998 // Async method lacks 'await' operators and will run synchronously.
 	}
 }

Runtime/Scripts/SceneImporter/ImporterMaterials.cs

@@ -790,7 +790,7 @@ void SetTransformKeyword()
 
 			foreach (var plugin in Context.Plugins)
 			{
-				plugin.OnAfterImportMaterial(def, materialIndex, mapper.Material);
+				await plugin.OnAfterImportMaterialAsync(def, materialIndex, mapper.Material);
 			}
 		}
 

Runtime/Scripts/SceneImporter/ImporterTextures.cs

@@ -658,7 +658,7 @@ TextureWrapMode UnityWrapMode(GLTF.Schema.WrapMode gltfWrapMode)
 
 				foreach (var plugin in Context.Plugins)
 				{
-					plugin.OnAfterImportTexture(texture, textureIndex, tex);
+					await plugin.OnAfterImportTextureAsync(texture, textureIndex, tex);
 				}
 			}
 			catch (Exception ex)