diff --git a/.github/copilot-instructions.md b/.github/copilot-instructions.md
new file mode 100644
index 0000000..a49f64a
--- /dev/null
+++ b/.github/copilot-instructions.md
@@ -0,0 +1,4 @@
+# Copilot Instructions
+
+## Project Guidelines
+- In MoonTools.ECS, do not store plain references to `Entity` objects in long-lived collections outside the ECS world, because their underlying IDs can be reused or destroyed. Instead, query the ECS world to track or process entities based on their assigned components.
\ No newline at end of file
diff --git a/Nerfed.Editor/Program.cs b/Nerfed.Editor/Program.cs
index dcf929b..1751a82 100644
--- a/Nerfed.Editor/Program.cs
+++ b/Nerfed.Editor/Program.cs
@@ -29,40 +29,40 @@ internal class Program
//systems.Add(new ParentSystem(world));
systems.Add(new LocalToWorldSystem(world));
editorSystems.Add(new EditorProfilerWindow(world));
- editorSystems.Add(new EditorHierarchyWindow(world));
+ // editorSystems.Add(new EditorHierarchyWindow(world));
#if DEBUG
editorSystems.Add(new EditorInspectorWindow(world));
#endif
- Entity ent1 = world.CreateEntity("parent");
- world.Set(ent1, new Root());
- world.Set(ent1, new LocalTransform(new Vector3(1, 0, 0), Quaternion.Identity, Vector3.One));
+ // Entity ent1 = world.CreateEntity("parent");
+ // world.Set(ent1, new Root());
+ // world.Set(ent1, new LocalTransform(new Vector3(1, 0, 0), Quaternion.Identity, Vector3.One));
+ //
+ // Entity ent2 = world.CreateEntity("child");
+ // world.Set(ent2, new LocalTransform(new Vector3(0, 1, 0), Quaternion.Identity, Vector3.One));
+ // Transform.SetParent(world, ent2, ent1);
+ //
+ // Entity ent3 = world.CreateEntity("entity3");
+ // world.Set(ent3, new Root());
+ // Transform.SetParent(world, ent3, ent2);
+ //
+ // Entity ent4 = world.CreateEntity("entity4");
+ // world.Set(ent4, new Root());
+ //
+ // Entity ent5 = world.CreateBaseEntity("entity5");
- Entity ent2 = world.CreateEntity("child");
- world.Set(ent2, new LocalTransform(new Vector3(0, 1, 0), Quaternion.Identity, Vector3.One));
- Transform.SetParent(world, ent2, ent1);
-
- Entity ent3 = world.CreateEntity("entity3");
- world.Set(ent3, new Root());
- Transform.SetParent(world, ent3, ent2);
-
- Entity ent4 = world.CreateEntity("entity4");
- world.Set(ent4, new Root());
-
- Entity ent5 = world.CreateBaseEntity("entity5");
-
- for (int i = 0; i < 256; i++)
+ for (int i = 0; i < 1000000; i++)
{
Entity newEnt = world.CreateBaseEntity();
world.Set(newEnt, new LocalTransform(new Vector3(i, i, i), Quaternion.Identity, Vector3.One));
- Entity parent = newEnt;
- for (int j = 0; j < 2; j++) {
- Entity newChildEnt = world.CreateEntity();
- world.Set(newChildEnt, new LocalTransform(new Vector3(i + j * i, i - j * i, j - i * i), Quaternion.Identity, Vector3.One));
- Transform.SetParent(world, newChildEnt, parent);
- parent = newChildEnt;
- }
+ // Entity parent = newEnt;
+ // for (int j = 0; j < 2; j++) {
+ // Entity newChildEnt = world.CreateEntity();
+ // world.Set(newChildEnt, new LocalTransform(new Vector3(i + j * i, i - j * i, j - i * i), Quaternion.Identity, Vector3.One));
+ // Transform.SetParent(world, newChildEnt, parent);
+ // parent = newChildEnt;
+ // }
}
// Open project.
diff --git a/Nerfed.Runtime/Components/LocalTransform.cs b/Nerfed.Runtime/Components/LocalTransform.cs
index 79b2cd4..04b6032 100644
--- a/Nerfed.Runtime/Components/LocalTransform.cs
+++ b/Nerfed.Runtime/Components/LocalTransform.cs
@@ -1,7 +1,9 @@
using System.Numerics;
+using Nerfed.Runtime.Scene;
namespace Nerfed.Runtime.Components
{
+ [SceneComponent]
public readonly record struct LocalTransform(Vector3 position, Quaternion rotation, Vector3 scale)
{
public static readonly LocalTransform Identity = new(Vector3.Zero, Quaternion.Identity, Vector3.One);
diff --git a/Nerfed.Runtime/Components/Test.cs b/Nerfed.Runtime/Components/Test.cs
index 9cd7e8d..9c93d7d 100644
--- a/Nerfed.Runtime/Components/Test.cs
+++ b/Nerfed.Runtime/Components/Test.cs
@@ -1,4 +1,7 @@
-namespace Nerfed.Runtime.Components
+using Nerfed.Runtime.Scene;
+
+namespace Nerfed.Runtime.Components
{
+ [SceneComponent]
public readonly record struct Test();
}
diff --git a/Nerfed.Runtime/Engine.cs b/Nerfed.Runtime/Engine.cs
index 3a7e894..1145eb5 100644
--- a/Nerfed.Runtime/Engine.cs
+++ b/Nerfed.Runtime/Engine.cs
@@ -16,7 +16,7 @@ public static class Engine
public static bool VSync { get; set; }
public static GraphicsDevice GraphicsDevice { get; private set; }
- public static AudioDevice AudioDevice { get; private set; }
+ //public static AudioDevice AudioDevice { get; private set; }
public static Window MainWindow { get; private set; }
public static TimeSpan Timestep { get; private set; }
@@ -44,37 +44,32 @@ public static class Engine
private const string WindowTitle = "Nerfed";
//..
- public static void Run(string[] args)
- {
+ public static void Run(string[] args) {
Timestep = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / TargetTimestep);
gameTimer = Stopwatch.StartNew();
SetFrameLimiter(new FrameLimiterSettings(FrameLimiterMode.Capped, MaxFps));
- for (int i = 0; i < previousSleepTimes.Length; i += 1)
- {
+ for(int i = 0; i < previousSleepTimes.Length; i += 1) {
previousSleepTimes[i] = TimeSpan.FromMilliseconds(1);
}
- if (SDL.SDL_Init(SDL.SDL_INIT_VIDEO | SDL.SDL_INIT_TIMER | SDL.SDL_INIT_GAMECONTROLLER) < 0)
- {
+ if(SDL.SDL_Init(SDL.SDL_INIT_VIDEO | SDL.SDL_INIT_TIMER | SDL.SDL_INIT_GAMECONTROLLER) < 0) {
throw new Exception("Failed to init SDL");
}
-
+
GraphicsDevice = new GraphicsDevice(BackendFlags.All);
GraphicsDevice.LoadDefaultPipelines();
MainWindow = new Window(GraphicsDevice, new WindowCreateInfo(WindowTitle, WindowWidth, WindowHeight, ScreenMode.Windowed));
- if (!GraphicsDevice.ClaimWindow(MainWindow, SwapchainComposition.SDR, VSync ? PresentMode.VSync : PresentMode.Mailbox))
- {
+ if(!GraphicsDevice.ClaimWindow(MainWindow, SwapchainComposition.SDR, VSync ? PresentMode.VSync : PresentMode.Mailbox)) {
throw new Exception("Failed to claim window");
}
- AudioDevice = new AudioDevice();
+ //AudioDevice = new AudioDevice();
OnInitialize?.Invoke();
- while (!quit)
- {
+ while(!quit) {
Tick();
}
@@ -83,40 +78,33 @@ public static class Engine
GraphicsDevice.UnclaimWindow(MainWindow);
MainWindow.Dispose();
GraphicsDevice.Dispose();
- AudioDevice.Dispose();
+ //AudioDevice.Dispose();
SDL.SDL_Quit();
}
///
/// Updates the frame limiter settings.
///
- public static void SetFrameLimiter(FrameLimiterSettings settings)
- {
+ public static void SetFrameLimiter(FrameLimiterSettings settings) {
framerateCapped = settings.Mode == FrameLimiterMode.Capped;
- if (framerateCapped)
- {
+ if(framerateCapped) {
framerateCapTimeSpan = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / settings.Cap);
- }
- else
- {
+ } else {
framerateCapTimeSpan = TimeSpan.Zero;
}
}
- public static void Quit()
- {
+ public static void Quit() {
quit = true;
}
- private static void Tick()
- {
+ private static void Tick() {
Profiler.BeginFrame();
AdvanceElapsedTime();
- if (framerateCapped)
- {
+ if(framerateCapped) {
Profiler.BeginSample("framerateCapped");
/* We want to wait until the framerate cap,
@@ -124,8 +112,7 @@ public static class Engine
* seeing how long we actually slept for lets us estimate the worst case
* sleep precision so we don't oversleep the next frame.
*/
- while (accumulatedDrawTime + worstCaseSleepPrecision < framerateCapTimeSpan)
- {
+ while(accumulatedDrawTime + worstCaseSleepPrecision < framerateCapTimeSpan) {
Thread.Sleep(1);
TimeSpan timeAdvancedSinceSleeping = AdvanceElapsedTime();
UpdateEstimatedSleepPrecision(timeAdvancedSinceSleeping);
@@ -136,8 +123,7 @@ public static class Engine
* SpinWait(1) works by pausing the thread for very short intervals, so it is
* an efficient and time-accurate way to wait out the rest of the time.
*/
- while (accumulatedDrawTime < framerateCapTimeSpan)
- {
+ while(accumulatedDrawTime < framerateCapTimeSpan) {
Thread.SpinWait(1);
AdvanceElapsedTime();
}
@@ -146,15 +132,12 @@ public static class Engine
}
// Do not let any step take longer than our maximum.
- if (accumulatedUpdateTime > MaxDeltaTime)
- {
+ if(accumulatedUpdateTime > MaxDeltaTime) {
accumulatedUpdateTime = MaxDeltaTime;
}
- if (!quit)
- {
- while (accumulatedUpdateTime >= Timestep)
- {
+ if(!quit) {
+ while(accumulatedUpdateTime >= Timestep) {
Profiler.BeginSample("Update");
Keyboard.Update();
Mouse.Update();
@@ -167,7 +150,7 @@ public static class Engine
OnUpdate?.Invoke();
Profiler.EndSample();
- AudioDevice.WakeThread();
+ //AudioDevice.WakeThread();
accumulatedUpdateTime -= Timestep;
Profiler.EndSample();
}
@@ -185,8 +168,7 @@ public static class Engine
Profiler.EndFrame();
}
- private static TimeSpan AdvanceElapsedTime()
- {
+ private static TimeSpan AdvanceElapsedTime() {
long currentTicks = gameTimer.Elapsed.Ticks;
TimeSpan timeAdvanced = TimeSpan.FromTicks(currentTicks - previousTicks);
accumulatedUpdateTime += timeAdvanced;
@@ -195,12 +177,9 @@ public static class Engine
return timeAdvanced;
}
- private static void ProcessSDLEvents()
- {
- while (SDL.SDL_PollEvent(out SDL.SDL_Event ev) == 1)
- {
- switch (ev.type)
- {
+ private static void ProcessSDLEvents() {
+ while(SDL.SDL_PollEvent(out SDL.SDL_Event ev) == 1) {
+ switch(ev.type) {
case SDL.SDL_EventType.SDL_QUIT:
Quit();
break;
@@ -236,16 +215,14 @@ public static class Engine
/* To calculate the sleep precision of the OS, we take the worst case
* time spent sleeping over the results of previous requests to sleep 1ms.
*/
- private static void UpdateEstimatedSleepPrecision(TimeSpan timeSpentSleeping)
- {
+ private static void UpdateEstimatedSleepPrecision(TimeSpan timeSpentSleeping) {
/* It is unlikely that the scheduler will actually be more imprecise than
* 4ms and we don't want to get wrecked by a single long sleep so we cap this
* value at 4ms for sanity.
*/
TimeSpan upperTimeBound = TimeSpan.FromMilliseconds(4);
- if (timeSpentSleeping > upperTimeBound)
- {
+ if(timeSpentSleeping > upperTimeBound) {
timeSpentSleeping = upperTimeBound;
}
@@ -254,17 +231,12 @@ public static class Engine
* is if we either 1) just got a new worst case, or 2) the worst case was
* the oldest entry on the list.
*/
- if (timeSpentSleeping >= worstCaseSleepPrecision)
- {
+ if(timeSpentSleeping >= worstCaseSleepPrecision) {
worstCaseSleepPrecision = timeSpentSleeping;
- }
- else if (previousSleepTimes[sleepTimeIndex] == worstCaseSleepPrecision)
- {
+ } else if(previousSleepTimes[sleepTimeIndex] == worstCaseSleepPrecision) {
TimeSpan maxSleepTime = TimeSpan.MinValue;
- for (int i = 0; i < previousSleepTimes.Length; i++)
- {
- if (previousSleepTimes[i] > maxSleepTime)
- {
+ for(int i = 0; i < previousSleepTimes.Length; i++) {
+ if(previousSleepTimes[i] > maxSleepTime) {
maxSleepTime = previousSleepTimes[i];
}
}
diff --git a/Nerfed.Runtime/Scene/ISceneSerializer.cs b/Nerfed.Runtime/Scene/ISceneSerializer.cs
new file mode 100644
index 0000000..55b7556
--- /dev/null
+++ b/Nerfed.Runtime/Scene/ISceneSerializer.cs
@@ -0,0 +1,13 @@
+namespace Nerfed.Runtime.Scene;
+
+///
+/// Abstraction over a concrete scene format (JSON, binary, …).
+/// Implementations read and write to a ,
+/// making it straightforward to add a compact binary format later without
+/// changing any of the surrounding scene infrastructure.
+///
+public interface ISceneSerializer
+{
+ void Serialize(SceneData scene, Stream stream);
+ SceneData Deserialize(Stream stream);
+}
diff --git a/Nerfed.Runtime/Scene/JsonSceneSerializer.cs b/Nerfed.Runtime/Scene/JsonSceneSerializer.cs
new file mode 100644
index 0000000..dc70c0b
--- /dev/null
+++ b/Nerfed.Runtime/Scene/JsonSceneSerializer.cs
@@ -0,0 +1,189 @@
+using System.Numerics;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace Nerfed.Runtime.Scene;
+
+///
+/// Human-readable JSON scene serializer.
+///
+/// Example output:
+///
+/// {
+/// "version": 1,
+/// "name": "MyScene",
+/// "entities": [
+/// {
+/// "id": "a1b2c3d4-...",
+/// "tag": "Player",
+/// "parentId": null,
+/// "components": [
+/// {
+/// "type": "Nerfed.Runtime.Components.LocalTransform",
+/// "data": {
+/// "position": { "x": 0.0, "y": 0.0, "z": 0.0 },
+/// "rotation": { "x": 0.0, "y": 0.0, "z": 0.0, "w": 1.0 },
+/// "scale": { "x": 1.0, "y": 1.0, "z": 1.0 }
+/// }
+/// }
+/// ]
+/// }
+/// ],
+/// "relations": [
+/// {
+/// "type": "Nerfed.Runtime.Components.OwnerRelation",
+/// "entityA": "a1b2c3d4-...",
+/// "entityB": "e5f6a7b8-...",
+/// "data": {}
+/// }
+/// ]
+/// }
+///
+///
+public sealed class JsonSceneSerializer : ISceneSerializer
+{
+ private static readonly JsonSerializerOptions Options = new() {
+ WriteIndented = true,
+ Converters =
+ {
+ new Vector3JsonConverter(),
+ new QuaternionJsonConverter(),
+ new SceneComponentDataJsonConverter(),
+ new SceneRelationDataJsonConverter(),
+ },
+ };
+
+ public void Serialize(SceneData scene, Stream stream) {
+ JsonSerializer.Serialize(stream, scene, Options);
+ }
+
+ public SceneData Deserialize(Stream stream) {
+ return JsonSerializer.Deserialize(stream, Options)
+ ?? throw new InvalidOperationException("Failed to deserialize scene: root element was null.");
+ }
+
+ // -------------------------------------------------------------------------
+ // Converters
+ // -------------------------------------------------------------------------
+
+ private sealed class Vector3JsonConverter : JsonConverter
+ {
+ public override Vector3 Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) {
+ float x = 0f, y = 0f, z = 0f;
+ reader.Read(); // StartObject
+ while(reader.Read() && reader.TokenType != JsonTokenType.EndObject) {
+ string name = reader.GetString()!;
+ reader.Read();
+ switch(name) {
+ case "x": x = reader.GetSingle(); break;
+ case "y": y = reader.GetSingle(); break;
+ case "z": z = reader.GetSingle(); break;
+ }
+ }
+ return new Vector3(x, y, z);
+ }
+
+ public override void Write(Utf8JsonWriter writer, Vector3 value, JsonSerializerOptions options) {
+ writer.WriteStartObject();
+ writer.WriteNumber("x", value.X);
+ writer.WriteNumber("y", value.Y);
+ writer.WriteNumber("z", value.Z);
+ writer.WriteEndObject();
+ }
+ }
+
+ private sealed class QuaternionJsonConverter : JsonConverter
+ {
+ public override Quaternion Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) {
+ float x = 0f, y = 0f, z = 0f, w = 1f;
+ reader.Read(); // StartObject
+ while(reader.Read() && reader.TokenType != JsonTokenType.EndObject) {
+ string name = reader.GetString()!;
+ reader.Read();
+ switch(name) {
+ case "x": x = reader.GetSingle(); break;
+ case "y": y = reader.GetSingle(); break;
+ case "z": z = reader.GetSingle(); break;
+ case "w": w = reader.GetSingle(); break;
+ }
+ }
+ return new Quaternion(x, y, z, w);
+ }
+
+ public override void Write(Utf8JsonWriter writer, Quaternion value, JsonSerializerOptions options) {
+ writer.WriteStartObject();
+ writer.WriteNumber("x", value.X);
+ writer.WriteNumber("y", value.Y);
+ writer.WriteNumber("z", value.Z);
+ writer.WriteNumber("w", value.W);
+ writer.WriteEndObject();
+ }
+ }
+
+ ///
+ /// Buffers the full JSON object, resolves the CLR component type from the "type" field,
+ /// then deserializes "data" using that concrete type.
+ ///
+ private sealed class SceneComponentDataJsonConverter : JsonConverter
+ {
+ public override SceneComponentData Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) {
+ using JsonDocument doc = JsonDocument.ParseValue(ref reader);
+ JsonElement root = doc.RootElement;
+
+ string typeName = root.GetProperty("type").GetString()
+ ?? throw new JsonException("Missing or null 'type' field in component data.");
+
+ Type componentType = SceneManager.GetComponentType(typeName)
+ ?? throw new JsonException($"Unknown component type '{typeName}'. Ensure the struct is marked with [SceneComponent].");
+
+ string rawData = root.GetProperty("data").GetRawText();
+ ValueType value = (ValueType)JsonSerializer.Deserialize(rawData, componentType, options)!;
+
+ return new SceneComponentData { Type = typeName, Value = value };
+ }
+
+ public override void Write(Utf8JsonWriter writer, SceneComponentData value, JsonSerializerOptions options) {
+ writer.WriteStartObject();
+ writer.WriteString("type", value.Type);
+ writer.WritePropertyName("data");
+ JsonSerializer.Serialize(writer, value.Value, value.Value.GetType(), options);
+ writer.WriteEndObject();
+ }
+ }
+
+ ///
+ /// Same pattern as but for relation data.
+ /// Resolves the type via .
+ ///
+ private sealed class SceneRelationDataJsonConverter : JsonConverter
+ {
+ public override SceneRelationData Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) {
+ using JsonDocument doc = JsonDocument.ParseValue(ref reader);
+ JsonElement root = doc.RootElement;
+
+ string typeName = root.GetProperty("type").GetString()
+ ?? throw new JsonException("Missing or null 'type' field in relation data.");
+
+ Type relationType = SceneManager.GetRelationType(typeName)
+ ?? throw new JsonException($"Unknown relation type '{typeName}'. Ensure the struct is marked with [SceneRelation].");
+
+ Guid entityA = root.GetProperty("entityA").GetGuid();
+ Guid entityB = root.GetProperty("entityB").GetGuid();
+
+ string rawData = root.GetProperty("data").GetRawText();
+ ValueType value = (ValueType)JsonSerializer.Deserialize(rawData, relationType, options)!;
+
+ return new SceneRelationData { Type = typeName, EntityA = entityA, EntityB = entityB, Value = value };
+ }
+
+ public override void Write(Utf8JsonWriter writer, SceneRelationData value, JsonSerializerOptions options) {
+ writer.WriteStartObject();
+ writer.WriteString("type", value.Type);
+ writer.WriteString("entityA", value.EntityA);
+ writer.WriteString("entityB", value.EntityB);
+ writer.WritePropertyName("data");
+ JsonSerializer.Serialize(writer, value.Value, value.Value.GetType(), options);
+ writer.WriteEndObject();
+ }
+ }
+}
\ No newline at end of file
diff --git a/Nerfed.Runtime/Scene/SceneComponentAttribute.cs b/Nerfed.Runtime/Scene/SceneComponentAttribute.cs
new file mode 100644
index 0000000..8202144
--- /dev/null
+++ b/Nerfed.Runtime/Scene/SceneComponentAttribute.cs
@@ -0,0 +1,8 @@
+namespace Nerfed.Runtime.Scene;
+
+///
+/// Marks an unmanaged struct as a serializable scene component.
+/// Only types with this attribute will be saved/loaded by the scene system.
+///
+[AttributeUsage(AttributeTargets.Struct, Inherited = false)]
+public sealed class SceneComponentAttribute : Attribute { }
diff --git a/Nerfed.Runtime/Scene/SceneData.cs b/Nerfed.Runtime/Scene/SceneData.cs
new file mode 100644
index 0000000..ee4f624
--- /dev/null
+++ b/Nerfed.Runtime/Scene/SceneData.cs
@@ -0,0 +1,65 @@
+namespace Nerfed.Runtime.Scene;
+
+///
+/// Root data model for a scene. A scene and a prefab are the same thing —
+/// there is no distinction between the two, mirroring Godot's design.
+///
+public sealed class SceneData
+{
+ /// Incremented when the file format changes in a breaking way.
+ public int Version { get; set; } = SceneData.CurrentVersion;
+ public string Name { get; set; } = string.Empty;
+ public List Entities { get; set; } = new();
+ /// All user-defined relations between entities in this scene.
+ public List Relations { get; set; } = new();
+
+ public const int CurrentVersion = 1;
+}
+
+///
+/// Serialized representation of a single entity.
+/// The is a scene-local identifier that only exists in the
+/// serialized data and is used to reconstruct parent–child and relation references.
+/// It is never stored as a component on a live entity.
+/// An entity is included if it owns at least one component
+/// OR participates in at least one relation.
+///
+public sealed class SceneEntityData
+{
+ public Guid Id { get; set; } = Guid.NewGuid();
+ public string Tag { get; set; } = string.Empty;
+
+ ///
+ /// Scene-local of this entity's
+ /// parent, or null if this is a root entity.
+ ///
+ public Guid? ParentId { get; set; }
+
+ public List Components { get; set; } = new();
+}
+
+///
+/// Serialized representation of a single component value on an entity.
+/// is the fully-qualified CLR type name used to resolve the component on load.
+/// is the boxed runtime value; each is
+/// responsible for converting it to/from its wire format.
+///
+public sealed class SceneComponentData
+{
+ public string Type { get; set; } = string.Empty;
+ public ValueType Value { get; set; } = default!;
+}
+
+///
+/// Serialized representation of a relation between two entities.
+/// and reference scene-local values.
+/// identifies the relation kind (must be marked with ).
+/// holds the relation data payload (may be an empty struct).
+///
+public sealed class SceneRelationData
+{
+ public string Type { get; set; } = string.Empty;
+ public Guid EntityA { get; set; }
+ public Guid EntityB { get; set; }
+ public ValueType Value { get; set; } = default!;
+}
diff --git a/Nerfed.Runtime/Scene/SceneManager.cs b/Nerfed.Runtime/Scene/SceneManager.cs
new file mode 100644
index 0000000..a703c51
--- /dev/null
+++ b/Nerfed.Runtime/Scene/SceneManager.cs
@@ -0,0 +1,345 @@
+using System.Reflection;
+using MoonTools.ECS;
+using Nerfed.Runtime.Components;
+
+namespace Nerfed.Runtime.Scene;
+
+///
+/// Central hub for scene serialization and deserialization.
+///
+/// On first use the static constructor scans all loaded assemblies for:
+/// • Structs annotated with — serialized as per-entity component data.
+/// • Structs annotated with — serialized as cross-entity relation data.
+///
+/// The hierarchy is handled separately via
+/// and does NOT need a .
+///
+/// Usage:
+///
+/// var serializer = new JsonSceneSerializer();
+/// SceneManager.Save(world, "Assets/level1.scene", serializer, "Level 1");
+/// SceneManager.Load(world, "Assets/level1.scene", serializer);
+///
+///
+public static class SceneManager
+{
+ // Full CLR type name → Type
+ private static readonly Dictionary ComponentRegistry = new();
+ private static readonly Dictionary RelationRegistry = new();
+
+ // Reflection cache so we only build the delegates once per type.
+ private static readonly Dictionary> HasComponentCache = new();
+ private static readonly Dictionary> GetComponentCache = new();
+ private static readonly Dictionary> SetComponentCache = new();
+ private static readonly Dictionary> HasOutRelationCache = new();
+ private static readonly Dictionary> OutRelationsCache = new();
+ private static readonly Dictionary> GetRelationDataCache = new();
+ private static readonly Dictionary> RelateCache = new();
+
+ static SceneManager() {
+ foreach(Assembly assembly in AppDomain.CurrentDomain.GetAssemblies()) {
+ Type[] types;
+ try { types = assembly.GetTypes(); } catch(ReflectionTypeLoadException ex) { types = ex.Types.Where(t => t is not null).ToArray()!; }
+
+ foreach(Type type in types) {
+ if(type.FullName is null) continue;
+
+ if(type.GetCustomAttribute() is not null)
+ ComponentRegistry[type.FullName] = type;
+
+ if(type.GetCustomAttribute() is not null)
+ RelationRegistry[type.FullName] = type;
+ }
+ }
+ }
+
+ // -------------------------------------------------------------------------
+ // Public registry accessors
+ // -------------------------------------------------------------------------
+
+ public static Type? GetComponentType(string fullName) {
+ ComponentRegistry.TryGetValue(fullName, out Type? type);
+ return type;
+ }
+
+ public static Type? GetRelationType(string fullName) {
+ RelationRegistry.TryGetValue(fullName, out Type? type);
+ return type;
+ }
+
+ public static IReadOnlyDictionary RegisteredComponentTypes => ComponentRegistry;
+ public static IReadOnlyDictionary RegisteredRelationTypes => RelationRegistry;
+
+ // -------------------------------------------------------------------------
+ // High-level Save / Load
+ // -------------------------------------------------------------------------
+
+ public static void Save(World world, string path, ISceneSerializer serializer, string sceneName = "") {
+ SceneData scene = Extract(world, sceneName);
+ string? directory = Path.GetDirectoryName(path);
+ if(!string.IsNullOrEmpty(directory))
+ Directory.CreateDirectory(directory);
+ using FileStream stream = File.Open(path, FileMode.Create, FileAccess.Write);
+ serializer.Serialize(scene, stream);
+ }
+
+ public static Dictionary Load(World world, string path, ISceneSerializer serializer) {
+ using FileStream stream = File.Open(path, FileMode.Open, FileAccess.Read);
+ SceneData scene = serializer.Deserialize(stream);
+ return Instantiate(world, scene);
+ }
+
+ // -------------------------------------------------------------------------
+ // Extract (world → SceneData)
+ // -------------------------------------------------------------------------
+
+ public static SceneData Extract(World world, string name = "") {
+ SceneData scene = new() { Name = name };
+
+ // ── 1. Collect entities ──────────────────────────────────────────────
+ // Include an entity if it has at least one scene component OR if it
+ // appears as an endpoint of at least one scene relation. This ensures
+ // pure grouping nodes and relation-only entities are not dropped.
+
+ Dictionary entityToGuid = new();
+
+ void EnsureEntity(Entity e) {
+ if(!entityToGuid.ContainsKey(e.ID))
+ entityToGuid[e.ID] = Guid.NewGuid();
+ }
+
+ foreach(Entity entity in world.GetAllEntities()) {
+ if(HasAnySceneComponent(world, entity))
+ EnsureEntity(entity);
+ }
+
+ // Walk all registered relation types and pull in both endpoints.
+ foreach(Type relationType in RelationRegistry.Values) {
+ foreach((Entity a, Entity b) in WorldAllRelations(world, relationType)) {
+ EnsureEntity(a);
+ EnsureEntity(b);
+ }
+ }
+
+ // Also include entities that are part of the ChildParentRelation hierarchy
+ // even if they carry no scene components and no user-defined relations.
+ foreach((Entity child, Entity parent) in world.Relations()) {
+ EnsureEntity(child);
+ EnsureEntity(parent);
+ }
+
+ // ── 2. Build entity records (parents must be known before children so
+ // we sort parents-before-children for readable output) ───────────
+ List ordered = BuildSortedEntityList(world, entityToGuid);
+ scene.Entities.AddRange(ordered);
+
+ // ── 3. Build relation records ────────────────────────────────────────
+ foreach((string typeName, Type relationType) in RelationRegistry) {
+ foreach((Entity a, Entity b) in WorldAllRelations(world, relationType)) {
+ if(!entityToGuid.TryGetValue(a.ID, out Guid guidA) ||
+ !entityToGuid.TryGetValue(b.ID, out Guid guidB))
+ continue;
+
+ ValueType payload = WorldGetRelationData(world, a, b, relationType);
+ scene.Relations.Add(new SceneRelationData {
+ Type = typeName,
+ EntityA = guidA,
+ EntityB = guidB,
+ Value = payload,
+ });
+ }
+ }
+
+ return scene;
+ }
+
+ // -------------------------------------------------------------------------
+ // Instantiate (SceneData → world)
+ // -------------------------------------------------------------------------
+
+ public static Dictionary Instantiate(World world, SceneData scene) {
+ Dictionary guidToEntity = new(scene.Entities.Count);
+
+ // Pass 1 – create all entities.
+ foreach(SceneEntityData entityData in scene.Entities) {
+ Entity entity = world.CreateEntity(entityData.Tag);
+ guidToEntity[entityData.Id] = entity;
+ }
+
+ // Pass 2 – set components and wire up the ChildParentRelation hierarchy.
+ foreach(SceneEntityData entityData in scene.Entities) {
+ Entity entity = guidToEntity[entityData.Id];
+
+ foreach(SceneComponentData componentData in entityData.Components)
+ WorldSetComponent(world, entity, componentData.Type, componentData.Value);
+
+ if(entityData.ParentId is Guid parentGuid && guidToEntity.TryGetValue(parentGuid, out Entity parent)) {
+ world.Set(entity, new Child());
+ world.Relate(entity, parent, new ChildParentRelation());
+ } else {
+ world.Set(entity, new Root());
+ }
+ }
+
+ // Pass 3 – restore all user-defined relations.
+ foreach(SceneRelationData relationData in scene.Relations) {
+ if(!guidToEntity.TryGetValue(relationData.EntityA, out Entity entityA) ||
+ !guidToEntity.TryGetValue(relationData.EntityB, out Entity entityB))
+ continue;
+
+ WorldRelate(world, entityA, entityB, relationData.Type, relationData.Value);
+ }
+
+ return guidToEntity;
+ }
+
+ // -------------------------------------------------------------------------
+ // Helpers – entity ordering
+ // -------------------------------------------------------------------------
+
+ // Returns entities sorted so that a parent always appears before its children,
+ // making the JSON file human-readable and easier to diff.
+ private static List BuildSortedEntityList(
+ World world,
+ Dictionary entityToGuid) {
+ // Build per-entity data (unsorted first).
+ Dictionary byGuid = new(entityToGuid.Count);
+
+ foreach((uint entityId, Guid guid) in entityToGuid) {
+ Entity entity = new(entityId);
+
+ Guid? parentId = null;
+ if(world.HasOutRelation(entity)) {
+ // Iterate all out-relations — an entity may have multiple parents
+ // in theory, but ChildParentRelation is designed as singleton.
+ // We capture the first valid one here.
+ foreach(Entity parent in world.OutRelations(entity)) {
+ if(entityToGuid.TryGetValue(parent.ID, out Guid parentGuid)) {
+ parentId = parentGuid;
+ break;
+ }
+ }
+ }
+
+ List components = new();
+ foreach((string typeName, Type componentType) in ComponentRegistry) {
+ if(!WorldHasComponent(world, entity, componentType)) continue;
+ ValueType value = WorldGetComponent(world, entity, componentType);
+ components.Add(new SceneComponentData { Type = typeName, Value = value });
+ }
+
+ byGuid[guid] = new SceneEntityData {
+ Id = guid,
+ Tag = world.GetTag(entity),
+ ParentId = parentId,
+ Components = components,
+ };
+ }
+
+ // Topological sort: parents before children.
+ List sorted = new(byGuid.Count);
+ HashSet visited = new(byGuid.Count);
+
+ void Visit(Guid id) {
+ if(!visited.Add(id)) return;
+ SceneEntityData data = byGuid[id];
+ if(data.ParentId is Guid pid && byGuid.ContainsKey(pid))
+ Visit(pid);
+ sorted.Add(data);
+ }
+
+ foreach(Guid id in byGuid.Keys)
+ Visit(id);
+
+ return sorted;
+ }
+
+ // -------------------------------------------------------------------------
+ // Reflection helpers – components
+ // -------------------------------------------------------------------------
+
+ private static bool HasAnySceneComponent(World world, Entity entity) {
+ foreach(Type componentType in ComponentRegistry.Values) {
+ if(WorldHasComponent(world, entity, componentType)) return true;
+ }
+ return false;
+ }
+
+ private static bool WorldHasComponent(World world, Entity entity, Type componentType) {
+ if(!HasComponentCache.TryGetValue(componentType, out Func? fn)) {
+ MethodInfo method = FindGenericMethod(nameof(World.Has)).MakeGenericMethod(componentType);
+ fn = (w, e) => (bool)method.Invoke(w, new object[] { e })!;
+ HasComponentCache[componentType] = fn;
+ }
+ return fn(world, entity);
+ }
+
+ private static ValueType WorldGetComponent(World world, Entity entity, Type componentType) {
+ if(!GetComponentCache.TryGetValue(componentType, out Func? fn)) {
+ MethodInfo method = FindGenericMethod(nameof(World.Get)).MakeGenericMethod(componentType);
+ fn = (w, e) => (ValueType)method.Invoke(w, new object[] { e })!;
+ GetComponentCache[componentType] = fn;
+ }
+ return fn(world, entity);
+ }
+
+ private static void WorldSetComponent(World world, Entity entity, string typeName, ValueType value) {
+ if(!ComponentRegistry.TryGetValue(typeName, out Type? componentType)) return;
+
+ if(!SetComponentCache.TryGetValue(componentType, out Action? fn)) {
+ MethodInfo method = FindGenericMethod(nameof(World.Set)).MakeGenericMethod(componentType);
+ fn = (w, e, v) => method.Invoke(w, new object[] { e, v });
+ SetComponentCache[componentType] = fn;
+ }
+ fn(world, entity, value);
+ }
+
+ // -------------------------------------------------------------------------
+ // Reflection helpers – relations
+ // -------------------------------------------------------------------------
+
+ private static IEnumerable<(Entity, Entity)> WorldAllRelations(World world, Type relationType) {
+ // World.Relations() returns ReverseSpanEnumerator<(Entity,Entity)>.
+ // We materialise it into a list so the caller can iterate freely.
+ MethodInfo method = FindGenericMethod(nameof(World.Relations)).MakeGenericMethod(relationType);
+ // Returns a boxed ReverseSpanEnumerator; invoke MoveNext/Current via dynamic.
+ // Easiest: call via dynamic to avoid unsafe span-from-box issues.
+ dynamic enumerator = method.Invoke(world, null)!;
+ List<(Entity, Entity)> results = new();
+ while(enumerator.MoveNext())
+ results.Add(enumerator.Current);
+ return results;
+ }
+
+ private static ValueType WorldGetRelationData(World world, Entity a, Entity b, Type relationType) {
+ if(!GetRelationDataCache.TryGetValue(relationType, out Func? fn)) {
+ MethodInfo method = FindGenericMethod(nameof(World.GetRelationData)).MakeGenericMethod(relationType);
+ fn = (w, ea, eb) => (ValueType)method.Invoke(w, new object[] { ea, eb })!;
+ GetRelationDataCache[relationType] = fn;
+ }
+ return fn(world, a, b);
+ }
+
+ private static void WorldRelate(World world, Entity a, Entity b, string typeName, ValueType value) {
+ if(!RelationRegistry.TryGetValue(typeName, out Type? relationType)) return;
+
+ if(!RelateCache.TryGetValue(relationType, out Action? fn)) {
+ MethodInfo method = FindGenericMethod(nameof(World.Relate)).MakeGenericMethod(relationType);
+ fn = (w, ea, eb, v) => method.Invoke(w, new object[] { ea, eb, v });
+ RelateCache[relationType] = fn;
+ }
+ fn(world, a, b, value);
+ }
+
+ // -------------------------------------------------------------------------
+ // Utility
+ // -------------------------------------------------------------------------
+
+ private static MethodInfo FindGenericMethod(string name) {
+ foreach(MethodInfo m in typeof(World).GetMethods(BindingFlags.Public | BindingFlags.Instance)) {
+ if(m.Name == name && m.IsGenericMethodDefinition)
+ return m;
+ }
+ throw new InvalidOperationException($"Could not find generic method '{name}' on {nameof(World)}.");
+ }
+}
diff --git a/Nerfed.Runtime/Scene/SceneRelationAttribute.cs b/Nerfed.Runtime/Scene/SceneRelationAttribute.cs
new file mode 100644
index 0000000..162bec9
--- /dev/null
+++ b/Nerfed.Runtime/Scene/SceneRelationAttribute.cs
@@ -0,0 +1,10 @@
+namespace Nerfed.Runtime.Scene;
+
+///
+/// Marks an unmanaged struct as a serializable scene relation kind.
+/// Both endpoints and the data payload will be saved/loaded by the scene system.
+/// The hierarchy is handled separately via
+/// and should NOT be marked with this attribute.
+///
+[AttributeUsage(AttributeTargets.Struct, Inherited = false)]
+public sealed class SceneRelationAttribute : Attribute { }
diff --git a/Nerfed.Runtime/Scene/Streaming/ChunkStreamingSystem.cs b/Nerfed.Runtime/Scene/Streaming/ChunkStreamingSystem.cs
new file mode 100644
index 0000000..0ccc397
--- /dev/null
+++ b/Nerfed.Runtime/Scene/Streaming/ChunkStreamingSystem.cs
@@ -0,0 +1,202 @@
+using MoonTools.ECS;
+using System.Collections.Generic;
+using System;
+using System.Numerics;
+using Nerfed.Runtime.Components;
+
+namespace Nerfed.Runtime.Scene.Streaming;
+
+///
+/// Status of a chunk in the streaming system.
+///
+public enum ChunkState
+{
+ Unloaded,
+ Loading,
+ Loaded,
+ Unloading
+}
+
+///
+/// A system that manages spatial partitioning. It determines which chunks should be loaded based on observers.
+///
+public class ChunkStreamingSystem : MoonTools.ECS.System
+{
+ private readonly struct ChunkCoord : IEquatable
+ {
+ public readonly int X;
+ public readonly int Y;
+ public readonly int Z;
+
+ // Pre-calculated on creation
+ public readonly long Id;
+
+ public ChunkCoord(int x, int y, int z)
+ {
+ X = x;
+ Y = y;
+ Z = z;
+
+ // We allocate 21 bits per axis (allowing ~2 million chunks positive and negative).
+ var hashX = (long)x & 0x1FFFFF;
+ var hashY = (long)y & 0x1FFFFF;
+ var hashZ = (long)z & 0x1FFFFF;
+
+ Id = hashX | (hashY << 21) | (hashZ << 42);
+ }
+
+ public bool Equals(ChunkCoord other) => Id == other.Id;
+ public override bool Equals(object? obj) => obj is ChunkCoord other && Equals(other);
+ public override int GetHashCode() => Id.GetHashCode();
+ }
+
+ // Configurable size of a chunk in world coordinates.
+ public float ChunkSize { get; set; } = 64f;
+
+ private readonly Filter _observerFilter;
+ private readonly Filter _chunkMemberFilter;
+ private readonly Filter _unloadedFilter;
+
+ // Active loaded/loading chunks
+ private readonly Dictionary _activeChunks = new();
+
+ // Queue of chunks waiting to be loaded
+ private readonly Queue _pendingLoads = new();
+
+ // Queue of chunks waiting to be completely tagged for unloading
+ private readonly Queue _pendingUnloads = new();
+
+ public ChunkStreamingSystem(World world) : base(world)
+ {
+ _observerFilter = FilterBuilder
+ .Include()
+ .Include() // Needs a world position
+ .Exclude() // Ignore dying observers
+ .Build();
+
+ _chunkMemberFilter = FilterBuilder
+ .Include()
+ .Exclude() // Ignore entities already marked for death
+ .Build();
+
+ _unloadedFilter = FilterBuilder
+ .Include()
+ .Build();
+ }
+
+ public override void Update(TimeSpan delta)
+ {
+ var requiredChunks = new HashSet();
+
+ // 1. Find all chunks that should be loaded based on observers
+ foreach (var observerEntity in _observerFilter.Entities)
+ {
+ var observer = Get(observerEntity);
+ var transform = Get(observerEntity);
+
+ // Convert world pos to grid coordinates
+ var worldPos = transform.localToWorldMatrix.Translation;
+ var centerChunk = GetChunkCoord(worldPos);
+
+ // Determine chunk radius based on observer radius and chunk size
+ int chunkRadius = (int)MathF.Ceiling(observer.ViewRadius / ChunkSize);
+
+ for (int x = -chunkRadius; x <= chunkRadius; x++)
+ {
+ for (int y = -chunkRadius; y <= chunkRadius; y++)
+ {
+ for (int z = -chunkRadius; z <= chunkRadius; z++)
+ {
+ var coord = new ChunkCoord(centerChunk.X + x, centerChunk.Y + y, centerChunk.Z + z);
+ requiredChunks.Add(coord);
+ }
+ }
+ }
+ }
+
+ // 2. Unload chunks that are active but no longer required
+ var chunksToUnload = new List();
+ foreach (var activeChunk in _activeChunks.Keys)
+ {
+ if (!requiredChunks.Contains(activeChunk) && _activeChunks[activeChunk] != ChunkState.Unloading)
+ {
+ chunksToUnload.Add(activeChunk);
+ }
+ }
+
+ foreach (var coord in chunksToUnload)
+ {
+ _activeChunks[coord] = ChunkState.Unloading;
+ _pendingUnloads.Enqueue(coord);
+ }
+
+ // 3. Queue newly required chunks
+ foreach (var coord in requiredChunks)
+ {
+ if (!_activeChunks.ContainsKey(coord))
+ {
+ // Mark as unloaded so we don't queue it multiple times
+ _activeChunks[coord] = ChunkState.Unloaded;
+ _pendingLoads.Enqueue(coord);
+ }
+ }
+
+ // 4. Process only ONE chunk load per frame to prevent stuttering
+ if (_pendingLoads.Count > 0)
+ {
+ var chunkToLoad = _pendingLoads.Dequeue();
+ // Double check it wasn't unloaded before we got around to loading it
+ if (_activeChunks.TryGetValue(chunkToLoad, out var state) && state == ChunkState.Unloaded)
+ {
+ LoadChunk(chunkToLoad);
+ }
+ }
+
+ // 5. Process only ONE chunk unload tagging per frame
+ if (_pendingUnloads.Count > 0)
+ {
+ var chunkToUnload = _pendingUnloads.Dequeue();
+ UnloadChunk(chunkToUnload);
+ }
+ }
+
+ private ChunkCoord GetChunkCoord(Vector3 worldPos)
+ {
+ return new ChunkCoord(
+ (int)MathF.Floor(worldPos.X / ChunkSize),
+ (int)MathF.Floor(worldPos.Y / ChunkSize),
+ (int)MathF.Floor(worldPos.Z / ChunkSize)
+ );
+ }
+
+ private void LoadChunk(ChunkCoord coord)
+ {
+ _activeChunks[coord] = ChunkState.Loading;
+
+ // TODO: In a real system, you'd queue async I/O here to read SceneData for this chunk
+ // and spawn the entities. Once they are all spawned, set state to Loaded.
+
+ // For demonstration, immediately set to loaded.
+ _activeChunks[coord] = ChunkState.Loaded;
+ }
+
+ private void UnloadChunk(ChunkCoord coord)
+ {
+ // Instead of destroying everything instantly, we tag the entities as 'Unloaded'
+ // so that they stop participating in rendering/gameplay, and get destroyed slowly
+ // by the ChunkTeardownSystem.
+ long coordId = coord.Id;
+ foreach (var entity in _chunkMemberFilter.Entities)
+ {
+ var chunkMember = Get(entity);
+ if (chunkMember.ChunkId == coordId)
+ {
+ Set(entity, new ChunkUnloadPendingTag());
+ }
+ }
+
+ // Immediately remove it from the required grid so it can be re-loaded
+ // if the player turns around quickly, while older entities are just garbage collected.
+ _activeChunks.Remove(coord);
+ }
+}
diff --git a/Nerfed.Runtime/Scene/Streaming/ChunkTeardownSystem.cs b/Nerfed.Runtime/Scene/Streaming/ChunkTeardownSystem.cs
new file mode 100644
index 0000000..f94d1fb
--- /dev/null
+++ b/Nerfed.Runtime/Scene/Streaming/ChunkTeardownSystem.cs
@@ -0,0 +1,35 @@
+using MoonTools.ECS;
+using System;
+
+namespace Nerfed.Runtime.Scene.Streaming;
+
+///
+/// A centralized cleanup system for slowly destroying chunk entities to avoid frame stutters.
+///
+public class ChunkTeardownSystem : MoonTools.ECS.System
+{
+ private readonly Filter _unloadedFilter;
+
+ // Adjustable limit to prevent massive stutters when unloading chunks.
+ public int MaxEntitiesToDestroyPerFrame { get; set; } = 250;
+
+ public ChunkTeardownSystem(World world) : base(world)
+ {
+ _unloadedFilter = FilterBuilder
+ .Include()
+ .Build();
+ }
+
+ public override void Update(TimeSpan delta)
+ {
+ int destroyed = 0;
+
+ foreach (var entity in _unloadedFilter.Entities)
+ {
+ if (destroyed >= MaxEntitiesToDestroyPerFrame) break;
+
+ Destroy(entity);
+ destroyed++;
+ }
+ }
+}
diff --git a/Nerfed.Runtime/Scene/Streaming/StreamingComponents.cs b/Nerfed.Runtime/Scene/Streaming/StreamingComponents.cs
new file mode 100644
index 0000000..0da245e
--- /dev/null
+++ b/Nerfed.Runtime/Scene/Streaming/StreamingComponents.cs
@@ -0,0 +1,28 @@
+using MoonTools.ECS;
+using System.Numerics;
+
+namespace Nerfed.Runtime.Scene.Streaming;
+
+///
+/// Marks an entity as a streaming observer (e.g. the player camera) that causes chunks
+/// to be loaded around it.
+///
+public struct ChunkObserverComponent
+{
+ public float ViewRadius;
+}
+
+///
+/// Tags an entity as belonging to a specific chunk, allowing it to be unloaded when the chunk is out of range.
+///
+public struct ChunkMemberComponent
+{
+ // A 64-bit spatial hash combining the X, Y, and Z coordinates.
+ public long ChunkId;
+}
+
+///
+/// Added to entities that belong to a chunk that has been unloaded.
+/// A dedicated system will process and destroy these slowly over multiple frames.
+///
+public struct ChunkUnloadPendingTag { }
diff --git a/Nerfed.Runtime/Systems/LocalToWorldSystem.cs b/Nerfed.Runtime/Systems/LocalToWorldSystem.cs
index 1949807..8e83ebe 100644
--- a/Nerfed.Runtime/Systems/LocalToWorldSystem.cs
+++ b/Nerfed.Runtime/Systems/LocalToWorldSystem.cs
@@ -1,6 +1,8 @@
using MoonTools.ECS;
using Nerfed.Runtime.Components;
using Nerfed.Runtime.Util;
+using System;
+using System.Collections.Generic;
using System.Numerics;
// TODO:
@@ -15,10 +17,19 @@ namespace Nerfed.Runtime.Systems
{
public class LocalToWorldSystem : MoonTools.ECS.System
{
- private readonly bool useParallelFor = true; // When having a low amount of transforms or when in debug mode this might be slower.
+ public override IReadOnlySet ReadsComponents { get; } = new HashSet { typeof(LocalTransform) };
+ public override IReadOnlySet WritesComponents { get; } = new HashSet { typeof(LocalToWorld) };
+
+ private readonly bool useParallelFor = true;
+ private const int ParallelForMinCount = 32; // Below this, parallel overhead costs more than it saves.
+ private static readonly System.Threading.Tasks.ParallelOptions ParallelOptions = new()
+ {
+ MaxDegreeOfParallelism = Environment.ProcessorCount
+ };
private readonly Filter rootEntitiesFilter;
private readonly Filter entitiesWithoutLocalToWorldFilter;
private readonly Action updateWorldTransform;
+ private ParallelWriter _parallelWriter;
public LocalToWorldSystem(World world) : base(world)
{
@@ -39,50 +50,64 @@ namespace Nerfed.Runtime.Systems
if (useParallelFor)
{
- Profiler.BeginSample("ParallelFor.LocalToWorldCheck");
// This check is needed because some entities might not have a LocalToWorld component yet.
// Adding this during the loop will break.
+ Profiler.BeginSample("ParallelFor.LocalToWorldCheck");
foreach (Entity entity in entitiesWithoutLocalToWorldFilter.Entities) {
Set(entity, new LocalToWorld(Matrix4x4.Identity));
}
Profiler.EndSample();
+ // Acquire a ParallelWriter AFTER pre-allocation — all entities now have LocalToWorld.
+ // This writer only permits updating existing values; no structural mutations allowed.
+ _parallelWriter = World.GetParallelWriter();
+
Profiler.BeginSample("ParallelFor.LocalToWorldUpdate");
- // This should only be used when the filter doesn't change by executing these functions!
- // So no entity deletion or setting/removing of components used by the filters in this loop.
- Parallel.For(0, rootEntitiesFilter.Count, updateWorldTransform);
+ if (rootEntitiesFilter.Count >= ParallelForMinCount)
+ {
+ Parallel.For(0, rootEntitiesFilter.Count, ParallelOptions, updateWorldTransform);
+ }
+ else
+ {
+ // Not enough work to justify thread overhead — run serially.
+ for (int i = 0; i < rootEntitiesFilter.Count; i++)
+ {
+ updateWorldTransform(i);
+ }
+ }
Profiler.EndSample();
}
else
{
foreach (Entity entity in rootEntitiesFilter.Entities)
{
- Profiler.BeginSample("UpdateWorldTransform");
+ // Profiler.BeginSample("UpdateWorldTransform");
UpdateWorldTransform(entity, Matrix4x4.Identity);
- Profiler.EndSample();
+ // Profiler.EndSample();
}
}
}
private void UpdateWorldTransformByIndex(int entityFilterIndex)
{
- Profiler.BeginSample("UpdateWorldTransformByIndex");
+ // Profiler.BeginSample("UpdateWorldTransformByIndex");
Entity entity = rootEntitiesFilter.NthEntity(entityFilterIndex);
UpdateWorldTransform(entity, Matrix4x4.Identity);
- Profiler.EndSample();
+ // Profiler.EndSample();
}
private void UpdateWorldTransform(in Entity entity, Matrix4x4 localToWorldMatrix)
{
- // TODO: Only update dirty transforms.
- // If a parent is dirty all the children need to update their localToWorld matrix.
- // How do we check if something is dirty? How do we know if a LocalTransform has been changed?
if (Has(entity))
{
LocalTransform localTransform = Get(entity);
localToWorldMatrix = Matrix4x4.Multiply(localToWorldMatrix, localTransform.TRS());
LocalToWorld localToWorld = new(localToWorldMatrix);
- Set(entity, localToWorld);
+
+ if (useParallelFor)
+ _parallelWriter.Set(entity, localToWorld); // thread-safe: direct write, no structural mutation
+ else
+ Set(entity, localToWorld);
}
ReverseSpanEnumerator childEntities = World.InRelations(entity);