add EventSystemBase

Sia.Examples/Example16_EventSystem.cs

@@ -0,0 +1,143 @@
+namespace Sia_Examples;
+
+using Sia;
+
+public static partial class Example16_EventSystem
+{
+    [SiaTemplate(nameof(Position))]
+    public record RPosition(int X, int Y);
+
+    public partial record struct Position
+    {
+        public readonly record struct MoveUp(int Count) : IEvent;
+        public readonly record struct MoveDown(int Count) : IEvent;
+        public readonly record struct MoveLeft(int Count) : IEvent;
+        public readonly record struct MoveRight(int Count) : IEvent;
+
+        public readonly record struct TestCommand : ICommand
+        {
+            public void Execute(World world, in EntityRef target)
+                => target.Get<Position>().X++;
+        }
+    }
+
+    public class TestEventSystem : EventSystemBase
+    {
+        public override void Initialize(World world, Scheduler scheduler)
+        {
+            base.Initialize(world, scheduler);
+            world.IndexHosts(Matchers.Of<Position>());
+
+            RecordEvent<Position.MoveUp>();
+            RecordEvent<Position.MoveDown>();
+            RecordEvent<Position.MoveLeft>();
+            RecordEvent<Position.MoveRight>();
+        }
+
+        private ref Position Get(in Identity id)
+            => ref World[id].Get<Position>();
+
+        protected override void HandleEvent<TEvent>(in Identity id, in TEvent e)
+        {
+            switch (e) {
+                case Position.MoveUp(int count):
+                    Console.WriteLine("Move Up!");
+                    Get(id).Y += count;
+                    break;
+                case Position.MoveDown(int count):
+                    Console.WriteLine("Move Down!");
+                    Get(id).Y -= count;
+                    break;
+                case Position.MoveLeft(int count):
+                    Console.WriteLine("Move Left!");
+                    Get(id).X -= count;
+                    break;
+                case Position.MoveRight(int count):
+                    Console.WriteLine("Move Right!");
+                    Get(id).X += count;
+                    break;
+            }
+        }
+    }
+
+    public class TestSnapshotEventSystem : SnapshotEventSystemBase<Position>
+    {
+        public override void Initialize(World world, Scheduler scheduler)
+        {
+            base.Initialize(world, scheduler);
+
+            RecordEvent<WorldEvents.Add<Position>>();
+            RecordRemovalEvent<WorldEvents.Add<Position>>();
+            RecordEvent<Position.TestCommand>();
+        }
+
+        protected override Position Snapshot<TEvent>(in EntityRef entity, in TEvent e)
+            => entity.Get<Position>();
+
+        protected override void HandleEvent<TEvent>(
+            in Identity id, in Position snapshot, in TEvent e)
+        {
+            switch (e) {
+                case Position.TestCommand:
+                    Console.WriteLine("Test Command!");
+                    Console.WriteLine("\tPrevious X: " + snapshot.X);
+                    break;
+            }
+        }
+    }
+
+    public class TestTemplateEventSystem : TemplateEventSystemBase<Position, RPosition>
+    {
+        protected override void HandleEvent<TEvent>(
+            in Identity id, in Position snapshot, in TEvent e)
+        {
+            switch (e) {
+                case WorldEvents.Add<Position>:
+                    Console.WriteLine("Position added!");
+                    break;
+                case WorldEvents.Remove<Position>:
+                    Console.WriteLine("Position removed!");
+                    break;
+
+                case Position.SetX:
+                    Console.WriteLine("Set X!");
+                    Console.WriteLine("\tPrevious X: " + snapshot.X);
+                    break;
+                case Position.SetY:
+                    Console.WriteLine("Set Y!");
+                    Console.WriteLine("\tPrevious Y: " + snapshot.Y);
+                    break;
+            }
+        }
+    }
+
+    public static void Run(World world)
+    {
+        var scheduler = new Scheduler();
+
+        SystemChain.Empty
+            .Add<TestTemplateEventSystem>()
+            .Add<TestEventSystem>()
+            .Add<TestSnapshotEventSystem>()
+            .RegisterTo(world, scheduler);
+
+        var e = world.CreateInArrayHost(HList.Create(new Position(1, 1)));
+        var pos = new Position.View(e);
+
+        e.Send(new Position.MoveUp(5));
+        e.Send(new Position.MoveLeft(5));
+        scheduler.Tick();
+
+        e.Modify(new Position.TestCommand());
+        scheduler.Tick();
+
+        pos.X += 10;
+        scheduler.Tick();
+
+        pos.Y += 5;
+        scheduler.Tick();
+
+        e.Remove<Position>();
+        scheduler.Tick();
+    }
+}

Sia.Examples/Program.cs

@@ -25,4 +25,5 @@ void Invoke(Action<World> action)
 Invoke(Example12_Addon.Run);
 Invoke(Example13_Parallel.Run);
 Invoke(Example14_RunnerWithContext.Run);
-Invoke(Example15_Serialization.Run);
+Invoke(Example15_Serialization.Run);
+Invoke(Example16_EventSystem.Run);