Improving performance by adding multithreading support (KhronosGroup#221

)

* Added multithreading support.

* Added multithreading support.

* Fixed spacing.

* fixes from PR

* fixed compile error

GLTFSerialization/GLTFSerialization/GLTFParser.cs

@@ -19,7 +19,7 @@ internal struct GLBHeader
 			public uint FileLength { get; set; }
 		}
 
-		public static GLTFRoot ParseJson(Stream stream, long startPosition = 0)
+		public static void ParseJson(Stream stream, out GLTFRoot gltfRoot, long startPosition = 0)
 		{
 			stream.Position = startPosition;
 			// Check for binary format magic bytes
@@ -32,7 +32,7 @@ public static GLTFRoot ParseJson(Stream stream, long startPosition = 0)
 				stream.Position = startPosition;
 			}
 
-			return GLTFRoot.Deserialize(new StreamReader(stream));
+			gltfRoot = GLTFRoot.Deserialize(new StreamReader(stream));
 		}
 
 		// Moves stream position to binary chunk location

GLTFSerialization/GLTFSerializationCLI/Program.cs

@@ -35,7 +35,8 @@ static void Main(string[] args)
 				goto exit;
 			}
 
-			GLTFRoot root = GLTFParser.ParseJson(stream);
+			GLTFRoot root;
+			GLTFParser.ParseJson(stream, out root);
 			ExtTextureTransformExtension ext = (ExtTextureTransformExtension)
 				root.Materials[1].PbrMetallicRoughness.BaseColorTexture.Extensions["EXT_texture_transform"];
 			root.Serialize(Console.Out);

GLTFSerialization/Tests/GLTFSerializationTests/GLTFLoaderTest.cs

@@ -24,7 +24,8 @@ public void LoadGLTFFromStream()
 			FileStream gltfStream = File.OpenRead(GLTF_PATH);
 
 			GLTFRoot.RegisterExtension(new TestExtensionFactory());
-			GLTFRoot gltfRoot = GLTFParser.ParseJson(gltfStream);
+			GLTFRoot gltfRoot = null;
+			GLTFParser.ParseJson(gltfStream, out gltfRoot);
 			GLTFJsonLoadTestHelper.TestGLTF(gltfRoot);
 		}
 
@@ -33,8 +34,9 @@ public void LoadKHRSpecGlossGLTFFromStream()
 		{
 			Assert.IsTrue(File.Exists(GLTF_PBR_SPECGLOSS_PATH));
 			FileStream gltfStream = File.OpenRead(GLTF_PBR_SPECGLOSS_PATH);
-
-			GLTFRoot gltfRoot = GLTFParser.ParseJson(gltfStream);
+
+			GLTFRoot gltfRoot;
+			GLTFParser.ParseJson(gltfStream, out gltfRoot);
 
 			Assert.IsNotNull(gltfRoot.ExtensionsUsed);
 			Assert.IsTrue(gltfRoot.ExtensionsUsed.Contains(KHR_materials_pbrSpecularGlossinessExtensionFactory.EXTENSION_NAME));
@@ -57,7 +59,8 @@ public void LoadGLBFromStream()
 		{
 			Assert.IsTrue(File.Exists(GLB_PATH));
 			FileStream gltfStream = File.OpenRead(GLB_PATH);
-			GLTFRoot gltfRoot = GLTFParser.ParseJson(gltfStream);
+			GLTFRoot gltfRoot;
+			GLTFParser.ParseJson(gltfStream, out gltfRoot);
 			GLTFJsonLoadTestHelper.TestGLB(gltfRoot);
 		}
 	}

GLTFSerialization/Tests/GLTFSerializationTests/GLTFRootTests.cs

@@ -28,7 +28,7 @@ public void Initialize()
 			writer.Flush();
 			stream.Position = 0;
 
-			_testRoot = GLTFParser.ParseJson(stream);
+			GLTFParser.ParseJson(stream, out _testRoot);
 
 		}
 

GLTFSerialization/Tests/GLTFSerializationTests/MergeNodesTest.cs

@@ -19,10 +19,12 @@ public void MergeNodes()
 			Assert.IsTrue(File.Exists(GLTF_LANTERN_PATH));
 
 			FileStream gltfBoomBoxStream = File.OpenRead(GLTF_BOOMBOX_PATH);
-			GLTFRoot boomBoxRoot = GLTFParser.ParseJson(gltfBoomBoxStream);
+			GLTFRoot boomBoxRoot;
+			GLTFParser.ParseJson(gltfBoomBoxStream, out boomBoxRoot);
 
 			FileStream gltfLanternStream = File.OpenRead(GLTF_LANTERN_PATH);
-			GLTFRoot lanternRoot = GLTFParser.ParseJson(gltfLanternStream);
+			GLTFRoot lanternRoot;
+			GLTFParser.ParseJson(gltfLanternStream, out lanternRoot);
 
 			GLTFRoot boomBoxCopy = new GLTFRoot(boomBoxRoot);
 

GLTFSerialization/Tests/GLTFSerializationUWPTests/GLTFUWPLoaderTest.cs

@@ -24,7 +24,8 @@ public async Task LoadGLTFFromStreamUWP()
 			StorageFile sampleFile = await StorageFile.GetFileFromApplicationUriAsync(new Uri(GLTF_PATH));
 
 			IRandomAccessStream gltfStream = await sampleFile.OpenAsync(FileAccessMode.Read);
-			GLTFRoot gltfRoot = GLTFParser.ParseJson(gltfStream.AsStream());
+			GLTFRoot gltfRoot;
+			GLTFParser.ParseJson(gltfStream.AsStream(), out gltfRoot);
 			GLTFJsonLoadTestHelper.TestGLTF(gltfRoot);
 		}
 
@@ -36,7 +37,8 @@ public async Task LoadKHRSpecGlossGLTFFromStreamUWP()
 
 
 			IRandomAccessStream gltfStream = await sampleFile.OpenAsync(FileAccessMode.Read);
-			GLTFRoot gltfRoot = GLTFParser.ParseJson(gltfStream.AsStreamForRead());
+			GLTFRoot gltfRoot;
+			GLTFParser.ParseJson(gltfStream.AsStreamForRead(), out gltfRoot);
 
 			Assert.IsNotNull(gltfRoot.ExtensionsUsed);
 			Assert.IsTrue(gltfRoot.ExtensionsUsed.Contains(KHR_materials_pbrSpecularGlossinessExtensionFactory.EXTENSION_NAME));

UnityGLTF/Assets/UnityGLTF/Examples/RootMergeComponent.cs

@@ -28,11 +28,13 @@ IEnumerator Start()
 
 			yield return loader0.LoadStream(Path.GetFileName(asset0Path));
 			var asset0Stream = loader0.LoadedStream;
-			var asset0Root = GLTFParser.ParseJson(asset0Stream);
+			GLTFRoot asset0Root;
+			GLTFParser.ParseJson(asset0Stream, out asset0Root);
 
 			yield return loader1.LoadStream(Path.GetFileName(asset1Path));
 			var asset1Stream = loader1.LoadedStream;
-			var asset1Root = GLTFParser.ParseJson(asset1Stream);
+			GLTFRoot asset1Root;
+			GLTFParser.ParseJson(asset0Stream, out asset1Root);
 
 			string newPath = "../../" + URIHelper.GetDirectoryName(asset0Path);
 
@@ -70,8 +72,8 @@ IEnumerator Start()
 				);
 
 			importer.MaximumLod = MaximumLod;
-
-			yield return importer.LoadScene(-1, Multithreaded);
+			importer.isMultithreaded = Multithreaded;
+			yield return importer.LoadScene(-1);
 		}
 #endif
 	}

UnityGLTF/Assets/UnityGLTF/Scripts/Editor/GLTFImporter.cs

@@ -336,14 +336,16 @@ private GameObject CreateGLTFScene(string projectFilePath)
             ILoader fileLoader = new FileLoader(Path.GetDirectoryName(projectFilePath));
             using (var stream = File.OpenRead(projectFilePath))
             {
-                GLTFRoot gLTFRoot = GLTFParser.ParseJson(stream);
+                GLTFRoot gLTFRoot;
+                GLTFParser.ParseJson(stream, out gLTFRoot);
                 var loader = new GLTFSceneImporter(gLTFRoot, fileLoader, stream);
 
                 loader.MaximumLod = _maximumLod;
+                loader.isMultithreaded = true;
 
                 // HACK: Force the coroutine to run synchronously in the editor
                 var stack = new Stack<IEnumerator>();
-                stack.Push(loader.LoadScene(isMultithreaded: true));
+                stack.Push(loader.LoadScene());
 
                 while (stack.Count > 0)
                 {

UnityGLTF/Assets/UnityGLTF/Scripts/GLTFComponent.cs

@@ -22,6 +22,7 @@ public class GLTFComponent : MonoBehaviour
 		private bool loadOnStart = true;
 
 		public int MaximumLod = 300;
+		public int Timeout = 8;
 		public GLTFSceneImporter.ColliderType Collider = GLTFSceneImporter.ColliderType.None;
 
 		[SerializeField]
@@ -69,8 +70,10 @@ public IEnumerator Load()
 				sceneImporter.SceneParent = gameObject.transform;
 				sceneImporter.Collider = Collider;
 				sceneImporter.MaximumLod = MaximumLod;
+				sceneImporter.Timeout = Timeout;
+				sceneImporter.isMultithreaded = Multithreaded;
 				sceneImporter.CustomShaderName = shaderOverride ? shaderOverride.name : null;
-				yield return sceneImporter.LoadScene(-1, Multithreaded);
+				yield return sceneImporter.LoadScene(-1);
 
 				// Override the shaders on all materials if a shader is provided
 				if (shaderOverride != null)

UnityGLTF/Assets/UnityGLTF/Scripts/GLTFSceneImporter.cs

@@ -3,6 +3,7 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Threading;
 using GLTF;
 using GLTF.Schema;
 using UnityEngine;
@@ -13,6 +14,7 @@
 using Matrix4x4 = GLTF.Math.Matrix4x4;
 using Object = UnityEngine.Object;
 using WrapMode = UnityEngine.WrapMode;
+using ThreadPriority = System.Threading.ThreadPriority;
 
 #if WINDOWS_UWP
 using System.Threading.Tasks;
@@ -41,6 +43,16 @@ public enum ColliderType
 		/// </summary>
 		public int MaximumLod = 300;
 
+		/// <summary>
+		/// Timeout for certain threading operations
+		/// </summary>
+		public int Timeout = 8;
+
+		/// <summary>
+		/// Use Multithreading or not
+		/// </summary>
+		public bool isMultithreaded = false;
+
 		/// <summary>
 		/// The parent transform for the created GameObject
 		/// </summary>
@@ -79,6 +91,7 @@ protected struct GLBStream
 		protected ILoader _loader;
 		private bool _isRunning = false;
 
+
 		/// <summary>
 		/// Creates a GLTFSceneBuilder object which will be able to construct a scene based off a url
 		/// </summary>
@@ -121,10 +134,9 @@ public GameObject LastLoadedScene
 		/// Loads a glTF Scene into the LastLoadedScene field
 		/// </summary>
 		/// <param name="sceneIndex">The scene to load, If the index isn't specified, we use the default index in the file. Failing that we load index 0.</param>
-		/// <param name="isMultithreaded">Whether all components should be loaded on a background thread</param>
 		/// <param name="onLoadComplete">Callback function for when load is completed</param>
 		/// <returns></returns>
-		public IEnumerator LoadScene(int sceneIndex = -1, bool isMultithreaded = false, Action<GameObject> onLoadComplete = null)
+		public IEnumerator LoadScene(int sceneIndex = -1, Action<GameObject> onLoadComplete = null)
 		{
 			try
 			{
@@ -142,7 +154,7 @@ public IEnumerator LoadScene(int sceneIndex = -1, bool isMultithreaded = false,
 				{
 					yield return LoadJson(_gltfFileName);
 				}
-				yield return _LoadScene(sceneIndex, isMultithreaded);
+				yield return _LoadScene(sceneIndex);
 
 				Cleanup();
 			}
@@ -291,11 +303,33 @@ protected IEnumerator ConstructImageBuffer(GLTFTexture texture, int textureIndex
 
 		private IEnumerator LoadJson(string jsonFilePath)
 		{
-			yield return _loader.LoadStream(jsonFilePath);
+			if (isMultithreaded && _loader.HasSyncLoadMethod)
+             {
+                 Thread loadThread = new Thread(() => _loader.LoadStreamSync(jsonFilePath));
+                 loadThread.Priority = ThreadPriority.Highest;
+                 loadThread.Start();
+                 yield return new WaitUntil(() => !loadThread.IsAlive);
+             }
+             else
+             {
+                 yield return _loader.LoadStream(jsonFilePath);
+             }
 
 			_gltfStream.Stream = _loader.LoadedStream;
 			_gltfStream.StartPosition = 0;
-			_gltfRoot = GLTFParser.ParseJson(_gltfStream.Stream, _gltfStream.StartPosition);
+
+			if (isMultithreaded)
+			{
+				Thread parseJsonThread = new Thread(() => GLTFParser.ParseJson(_gltfStream.Stream, out _gltfRoot, _gltfStream.StartPosition));
+				parseJsonThread.Priority = ThreadPriority.Highest;
+				parseJsonThread.Start();
+				yield return new WaitUntil(() => !parseJsonThread.IsAlive);
+			}
+			else
+			{
+				GLTFParser.ParseJson(_gltfStream.Stream, out _gltfRoot, _gltfStream.StartPosition);
+				yield return null;
+			}
 		}
 
 		private IEnumerator _LoadNode(int nodeIndex)
@@ -327,9 +361,8 @@ protected void InitializeAssetCache()
 		/// Creates a scene based off loaded JSON. Includes loading in binary and image data to construct the meshes required.
 		/// </summary>
 		/// <param name="sceneIndex">The bufferIndex of scene in gltf file to load</param>
-		/// <param name="isMultithreaded">Whether to use a thread to do loading</param>
 		/// <returns></returns>
-		protected IEnumerator _LoadScene(int sceneIndex = -1, bool isMultithreaded = false)
+		protected IEnumerator _LoadScene(int sceneIndex = -1)
 		{
 			GLTFScene scene;
 			InitializeAssetCache(); // asset cache currently needs initialized every time due to cleanup logic
@@ -482,10 +515,19 @@ protected virtual IEnumerator ConstructUnityTexture(Stream stream, bool markGpuO
 						throw new Exception("Stream is larger than can be copied into byte array");
 					}
 
-					stream.Read(buffer, 0, (int)stream.Length);
-				}
-
-				yield return null;
+					if (isMultithreaded)
+					{
+						Thread readThread = new Thread(() => stream.Read(buffer, 0, (int)stream.Length));
+						readThread.Priority = ThreadPriority.Highest;
+						readThread.Start();
+						yield return new WaitUntil(() => !readThread.IsAlive);
+					}
+					else
+					{
+						stream.Read(buffer, 0, (int)stream.Length);
+						yield return null;
+					}					
+				}				
 
 				//	NOTE: the second parameter of LoadImage() marks non-readable, but we can't mark it until after we call Apply()
 				texture.LoadImage(buffer, false);
@@ -562,7 +604,21 @@ protected virtual IEnumerator ConstructMeshAttributes(MeshPrimitive primitive, i
 					attributeAccessors[SemanticProperties.INDICES] = indexBuilder;
 				}
 
-				GLTFHelpers.BuildMeshAttributes(ref attributeAccessors);
+				if (isMultithreaded)
+				{
+					Thread buildMeshAttributesThread = new Thread(() => GLTFHelpers.BuildMeshAttributes(ref attributeAccessors));
+					buildMeshAttributesThread.Priority = ThreadPriority.Highest;
+					buildMeshAttributesThread.Start();
+					while (!buildMeshAttributesThread.Join(Timeout))
+					{
+						yield return null;
+					}
+				}
+				else
+				{
+					GLTFHelpers.BuildMeshAttributes(ref attributeAccessors);
+				}
+
 				TransformAttributes(ref attributeAccessors);
 				_assetCache.MeshCache[meshID][primitiveIndex].MeshAttributes = attributeAccessors;
 			}

UnityGLTF/Assets/UnityGLTF/Scripts/Loader/FileLoader.cs

@@ -15,9 +15,12 @@ public class FileLoader : ILoader
 		private string _rootDirectoryPath;
 		public Stream LoadedStream { get; private set; }
 
+		public bool HasSyncLoadMethod { get; private set; }
+
 		public FileLoader(string rootDirectoryPath)
 		{
 			_rootDirectoryPath = rootDirectoryPath;
+			HasSyncLoadMethod = true;
 		}
 
 		public IEnumerator LoadStream(string gltfFilePath)
@@ -41,5 +44,26 @@ private IEnumerator LoadFileStream(string rootPath, string fileToLoad)
 			yield return null;
 			LoadedStream = File.OpenRead(pathToLoad);
 		}
+
+		public void LoadStreamSync(string gltfFilePath)
+ 	    {
+ 	        if (gltfFilePath == null)
+ 	        {
+ 	            throw new ArgumentNullException("gltfFilePath");
+ 	        }
+
+ 	        LoadFileStreamSync(_rootDirectoryPath, gltfFilePath);
+ 	    }
+
+ 	    private void LoadFileStreamSync(string rootPath, string fileToLoad)
+ 	    {
+ 	        string pathToLoad = Path.Combine(rootPath, fileToLoad);
+ 	        if (!File.Exists(pathToLoad))
+ 	        {
+ 	            throw new FileNotFoundException("Buffer file not found", fileToLoad);
+ 	        }
+
+ 	        LoadedStream = File.OpenRead(pathToLoad);
+ 	    }
 	}
 }

UnityGLTF/Assets/UnityGLTF/Scripts/Loader/ILoader.cs

@@ -12,6 +12,10 @@ public interface ILoader
 	{
 		IEnumerator LoadStream(string relativeFilePath);
 
+		void LoadStreamSync(string jsonFilePath);
+
 		Stream LoadedStream { get; }
+
+		bool HasSyncLoadMethod { get; }
 	}
 }