UUID

GlitchyEngine/src/Core/UUID.bf

@@ -0,0 +1,53 @@
+using Bon;
+using System;
+using Bon.Integrated;
+using System.Collections;
+
+namespace GlitchyEngine.Core
+{
+	[BonTarget]
+	struct UUID : IHashable
+	{
+		[BonInclude]
+		private uint64 _uuid;
+
+		private static Random s_Random = new .() ~ delete _;
+
+		static this()
+		{
+			gBonEnv.typeHandlers.Add(typeof(UUID),
+				((.)new => Serialize, (.)new => Deserialize));
+		}
+
+		/// Creates a new random UUID.
+		public this()
+		{
+			_uuid = s_Random.NextU64();
+		}
+		
+		/// Creates a new UUID with the given value.
+		public this(uint64 uuid)
+		{
+			_uuid = uuid;
+		}
+
+		public int GetHashCode()
+		{
+			return (int)_uuid;
+		}
+
+		static void Serialize(BonWriter writer, ValueView val, BonEnvironment env)
+		{
+			UUID uuid = *(UUID*)val.dataPtr;
+
+			Bon.Integrated.Serialize.[Friend]Integer(typeof(uint64), writer, ValueView(typeof(uint64), &uuid._uuid));
+		}
+
+		public static Result<void> Deserialize(BonReader reader, ValueView val, BonEnvironment env)
+		{
+			Bon.Integrated.Deserialize.[Friend]Integer!(typeof(uint64), reader, val);
+
+			return .Ok;
+		}
+	}
+}

GlitchyEngine/src/World/Components.bf

@@ -1,6 +1,7 @@
 using System;
 using GlitchyEngine.Math;
 using GlitchyEngine.Renderer;
+using GlitchyEngine.Core;
 
 namespace GlitchyEngine.World
 {
@@ -15,6 +16,22 @@ namespace GlitchyEngine.World
 		}
 	}
 
+	struct IDComponent
+	{
+		public readonly UUID ID;
+
+		/// Create aa new IDComponent with a random UUID.
+		public this()
+		{
+			ID = UUID();
+		}
+
+		public this(UUID id)
+		{
+			ID = id;
+		}
+	}
+
 	/// If an entity has the EditorComponent it won't be displayed in the scene hierarchy.
 	struct EditorComponent
 	{

GlitchyEngine/src/World/Entity.bf

@@ -1,5 +1,6 @@
 using System;
 using System.Collections;
+using GlitchyEngine.Core;
 
 using internal GlitchyEngine.World;
 
@@ -63,6 +64,8 @@ namespace GlitchyEngine.World
 			}
 		}
 
+		public UUID UUID => GetComponent<IDComponent>().ID;
+
 		public TransformComponent* Transform => GetComponent<TransformComponent>();
 
 		public T* AddComponent<T>(T value = T()) where T: struct, new

GlitchyEngine/src/World/Scene.bf

@@ -3,6 +3,7 @@ using GlitchyEngine.Renderer;
 using System;
 using System.Collections;
 using Box2D;
+using GlitchyEngine.Core;
 
 namespace GlitchyEngine.World
 {
@@ -24,6 +25,9 @@ namespace GlitchyEngine.World
 
 		private Effect _gammaCorrectEffect ~ _.ReleaseRef();
 
+		// Maps ids to the entities they represent.
+		private Dictionary<UUID, EcsEntity> _idToEntity = new .() ~ delete _;
+
 		public Entity ActiveCamera => {
 			Entity cameraEntity = .();
 
@@ -205,6 +209,8 @@ namespace GlitchyEngine.World
 				}
 			}
 
+			renderTarget = _cameraTarget..AddRef();
+
 			// 3D render
 			Renderer.BeginScene(*primaryCamera, primaryCameraTransform, renderTarget, _compositeTarget);
 
@@ -468,13 +474,20 @@ namespace GlitchyEngine.World
 		}
 
 		/// Creates a new Entity with the given name.
-		public Entity CreateEntity(String name = "")
+		public Entity CreateEntity(String name = "", UUID id = default)
 		{
 			Entity entity = Entity(_ecsWorld.NewEntity(), this);
 			entity.AddComponent<TransformComponent>();
 
 			let nameComponent = entity.AddComponent<DebugNameComponent>();
 			nameComponent.SetName(name.IsEmpty ? "Entity" : name);
+			
+			// If no id is given generate a random one.
+			IDComponent idComponent = (id == default) ? IDComponent() : IDComponent(id);
+
+			entity.AddComponent<IDComponent>(idComponent);
+
+			_idToEntity.Add(idComponent.ID, entity.Handle);
 
 			return entity;
 		}
@@ -485,6 +498,8 @@ namespace GlitchyEngine.World
 		*/
 		public void DestroyEntity(Entity entity, bool destroyChildren = false)
 		{
+			_idToEntity.Remove(entity.UUID);
+
 			if (destroyChildren)
 			{
 				for (Entity child in entity.EnumerateChildren)
@@ -496,6 +511,16 @@ namespace GlitchyEngine.World
 			_ecsWorld.RemoveEntity(entity.Handle);
 		}
 
+		public Result<Entity> GetEntityByID(UUID id)
+		{
+			if (_idToEntity.TryGetValue(id, let ecsEntity))
+			{
+				return .Ok(Entity(ecsEntity, this));
+			}
+
+			return .Err;
+		}
+
 		private uint32 ViewportWidth, ViewportHeight;
 
 		/// Sets the size of the viewport into which the scene will be rendered.

GlitchyEngine/src/World/SceneSerializer.bf

@@ -4,6 +4,8 @@ using System;
 using System.Reflection;
 using System.IO;
 using GlitchyEngine.Math;
+using GlitchyEngine.Core;
+using System.Collections;
 
 namespace GlitchyEngine.World
 {
@@ -13,6 +15,11 @@ namespace GlitchyEngine.World
 	{
 		private Scene _scene;
 
+		// Maps from ParentID to ChildEntity
+		private Dictionary<UUID, Entity> _parentIdToChild;
+
+		private List<(Entity Entity, UUID ParentId)> _entitiesMissingParent;
+
 		public this(Scene scene)
 		{
 			_scene = scene;
@@ -60,14 +67,13 @@ namespace GlitchyEngine.World
 			File.WriteAllText(filePath, buffer);
 		}
 
-		static void SerializeEntity(BonWriter writer, Entity entity)
+		void SerializeEntity(BonWriter writer, Entity entity)
 		{
 			writer.EntryStart();
 
 			using (writer.ObjectBlock())
 			{
-				// TODO: Entity GUID goes here!
-				Serialize.Value(writer, "Id", entity.Handle.Index);
+				Serialize.Value(writer, "Id", entity.UUID);
 				
 				SerializeComponent<EditorComponent>(writer, entity, "EditorComponent", scope (component) => {});
 
@@ -88,7 +94,10 @@ namespace GlitchyEngine.World
 				{
 					// TODO: Use GUIDs
 					if (component.Parent != .InvalidEntity)
-						Serialize.Value(writer, "ParentId", component.Parent.Index);
+					{
+						Entity parent = Entity(component.Parent, _scene);
+						Serialize.Value(writer, "ParentId", parent.UUID);
+					}
 
 					Serialize.Value(writer, "Position", component.Position);
 					Serialize.Value(writer, "Rotation", component.Rotation);
@@ -177,6 +186,9 @@ namespace GlitchyEngine.World
 		{
 			Debug.Profiler.ProfileResourceFunction!();
 
+			_parentIdToChild = scope Dictionary<UUID, Entity>();
+			_entitiesMissingParent = scope List<(Entity Entity, UUID ParentId)>();
+
 			String buffer = scope String();
 			File.ReadAllText(filePath, buffer);
 
@@ -217,6 +229,19 @@ namespace GlitchyEngine.World
 
 			Try!(Deserialize.End(reader));
 
+			// Find parents for entities that don't have their parent yet
+			for ((Entity Entity, UUID ParentId) entry in _entitiesMissingParent)
+			{
+				let parentResult = _scene.GetEntityByID(entry.ParentId);
+
+				Log.EngineLogger.Assert(parentResult case .Ok, "Parent entity does not exist.");
+
+				if (parentResult case .Ok(let parent))
+				{
+					entry.Entity.Parent = parent;
+				}
+			}
+
 			return .Ok;
 		}
 
@@ -224,10 +249,9 @@ namespace GlitchyEngine.World
 		{
 			Try!(reader.ObjectBlock());
 			
-			Entity entity = _scene.CreateEntity();
+			Deserialize.Value<uint64>(reader, "Id", let uuid);
 
-			// TODO: GUID?
-			Deserialize.Value<uint32>(reader, "Id", let id);
+			Entity entity = _scene.CreateEntity("", UUID(uuid));
 
 			while(reader.ObjectHasMore())
 			{
@@ -282,10 +306,21 @@ namespace GlitchyEngine.World
 						let nextId = Try!(reader.Identifier());
 						if (nextId == "ParentId")
 						{
-							// TODO: Use GUIDs
-							uint32 pId;
+							UUID pId;
 							Deserialize.Value(reader, out pId);
 							reader.EntryEnd();
+
+							var parentEntity = _scene.GetEntityByID(pId);
+
+							if (parentEntity case .Ok(let parent))
+							{
+								component.Parent = parent.Handle;
+							}
+							else
+							{
+								_entitiesMissingParent.Add((entity, pId));
+							}
+
 							Deserialize.Value(reader, "Position", out component.[Friend]_position);
 							reader.EntryEnd();
 						}