implemented ECS

Kamni/src/Engine/Component.cs

@@ -0,0 +1,11 @@
+namespace Kamni.Engine;
+
+public class Component
+{
+    public Entity E { get; internal init; } = null!;
+    
+    public virtual void Update(FrameInfo frame)
+    {
+        
+    }
+}

Kamni/src/Engine/Entity.cs

@@ -0,0 +1,48 @@
+using Raylib_cs;
+
+namespace Kamni.Engine;
+
+public class Entity
+{
+    public readonly long Id;
+    public Vector2 Position;
+    public Vector2 Scale;
+    public float Rotation;
+    
+    private readonly Dictionary<Type, Component> _components = new();
+
+    internal Entity(long id)
+    {
+        Id = id;
+    }
+
+    internal void InvokeUpdate(FrameInfo frame)
+    {
+        foreach (var (type, component) in _components)
+        {
+            component.Update(frame);
+        }
+    }
+
+    public T AddComponent<T>() where T : Component, new()
+    {
+        var component = new T() { E = this };
+        _components.Add(typeof(T), component);
+        return component;
+    }
+
+    public T? TryGetComponent<T>() where T : Component
+    {
+        if (_components.TryGetValue(typeof(T), out var component))
+            return (T)component;
+        return null;
+    }
+
+    public T GetComponent<T>() where T : Component
+    {
+        var component = TryGetComponent<T>();
+        if (component is null)
+            throw new Exception($"Component '{typeof(T).AssemblyQualifiedName}' not found in entity {Id}");
+        return component;
+    }
+}

Kamni/src/Engine/FrameInfo.cs

@@ -0,0 +1,3 @@
+namespace Kamni.Engine;
+
+public record struct FrameInfo(long Number, float deltaT);

Kamni/src/Engine/Scene.cs

@@ -0,0 +1,31 @@
+namespace Kamni.Engine;
+
+public class Scene
+{
+    // TODO: Replace List with some structure with fast Remove(id) 
+    private readonly List<Entity?> _entities = new();
+
+    public IReadOnlyList<Entity?> Entities => _entities;
+
+    public Entity CreateEntity()
+    {
+        Entity e = new Entity(_entities.Count);
+        _entities.Add(e);
+        return e;
+    }
+
+    public void RemoveEntity(Entity e)
+    {
+        // waste 8 bytes in the list to store null at index e.Id
+        // TODO: remove memory leak
+        _entities[(int)e.Id] = null;
+    }
+    
+    internal void InvokeUpdate(FrameInfo frame)
+    {
+        foreach (var entity in _entities)
+        {
+            entity?.InvokeUpdate(frame);
+        }
+    }
+}

Kamni/src/Engine/Sprite.cs

@@ -0,0 +1,8 @@
+using Raylib_cs;
+
+namespace Kamni.Engine;
+
+public class Sprite
+{
+    public Texture2D Texture;
+}

Kamni/src/Program.cs

@@ -1,14 +1,16 @@
 global using System;
 global using System.Numerics;
+global using System.Collections.Generic;
 global using DTLib.Logging;
 global using DTLib.Filesystem;
 global using File = DTLib.Filesystem.File;
 global using Directory = DTLib.Filesystem.Directory;
 global using Path = DTLib.Filesystem.Path;
+global using static Raylib_cs.Raylib;
 using System.Linq;
 using System.Runtime.InteropServices;
+using Kamni.Engine;
 using Raylib_cs;
-using static Raylib_cs.Raylib;
 
 namespace Kamni;
 
@@ -17,6 +19,9 @@ public static class Program
     public static readonly Version GameVersion = new(0, 1, 0);
     public static Settings Settings { get; private set; } = null!;
     public static ILogger Logger { get; private set; } = null!;
+
+    public static Camera2D Camera = new(new Vector2(), new Vector2(), 0, 1);
+    
     
     public static int Main(string[] args)
     {
@@ -52,43 +57,79 @@ public static class Program
         
         SetWindowMinSize(480, 360);
         InitWindow(Settings.WindowMode == WindowMode.Window ? 720 : 0 , Settings.WindowMode == WindowMode.Window ? 480 : 0, $"Kamni v{GameVersion}");
+
+        var scene = new Scene();
+        var octagon0 = scene.CreateEntity().AddComponent<PolygonalSprite>();
+        var octagon1 = scene.CreateEntity().AddComponent<PolygonalSprite>();
+        var octagon2 = scene.CreateEntity().AddComponent<PolygonalSprite>();
+        var octagon3 = scene.CreateEntity().AddComponent<PolygonalSprite>();
+        var octagon4 = scene.CreateEntity().AddComponent<PolygonalSprite>();
+        var octagon5 = scene.CreateEntity().AddComponent<PolygonalSprite>();
+        var octagon6 = scene.CreateEntity().AddComponent<PolygonalSprite>();
+        
+        octagon0.Color = Color.Red;
+        octagon0.E.Position = new(0, -100);
+        octagon1.Color = Color.Pink;
+        octagon1.E.Position = new(-100, -50);
+        octagon2.Color = Color.Orange;
+        octagon2.E.Position = new(100, -50);
+        octagon3.Color = Color.Purple;
+        octagon3.E.Position = new(-150, 25);
+        octagon4.Color = Color.Yellow;
+        octagon4.E.Position = new(150, 25);
+        octagon5.Color = Color.SkyBlue;
+        octagon5.E.Position = new(-60, 75);
+        octagon6.Color = Color.Green;
+        octagon6.E.Position = new(60, 75);
+
+        FrameInfo frameInfo = new FrameInfo();
         while (!WindowShouldClose())
         {
             BeginDrawing();
-            DrawFrame();
+            frameInfo.Number++;
+            frameInfo.deltaT = GetFrameTime();
+            
+            Vector2 center = new(GetRenderWidth() / 2f, GetRenderHeight() / 2f);
+            Camera.Offset = center;
+            
+            ClearBackground(Color.DarkBlue);
+        
+            BeginMode2D(Camera);
+            scene.InvokeUpdate(frameInfo);
+            EndMode2D();
+            
+            DrawFPS(5, 5);
+            
             EndDrawing();
         }
         
         CloseWindow();
         return 0;
     }
-
-    static float[] randomRotations = [];
-    static float sumT = 999999;
     
-    static void DrawFrame()
+    
+    class PolygonalSprite : Component
     {
+        public Color Color = Color.White;
+        public int Sides = 5;
+        public int Radius = 32;
         
-        Vector2 center =  new(GetRenderWidth() / 2f, GetRenderHeight() / 2f);
-        float deltaT = GetFrameTime();
-        sumT += deltaT;
-        if (sumT > 0.5)
+        static float sumT = 999999;
+        
+        public override void Update(FrameInfo frame)
         {
-            sumT = 0;
-            randomRotations = Enumerable.Range(0, 7).Select(_ => (float)Random.Shared.Next(-30, 30)).ToArray();
+            DrawPoly(E.Position, Sides, Radius, E.Rotation, Color);
+            
+            sumT += frame.deltaT;
+            if (sumT > 0.5)
+            {
+                sumT = 0;
+                E.Rotation = Random.Shared.Next(-30, 30);
+            }
         }
-        ClearBackground(Color.DarkBlue);
-        DrawPoly(new(center.X, center.Y - 100), 5, 32, randomRotations[0], Color.Red);
-        DrawPoly(new(center.X - 100, center.Y - 50), 5, 32, randomRotations[1], Color.Pink);
-        DrawPoly(new(center.X + 100, center.Y - 50), 5, 32, randomRotations[2], Color.Orange);
-        DrawPoly(new(center.X - 150, center.Y + 25), 5, 32, randomRotations[3], Color.Purple);
-        DrawPoly(new(center.X + 150, center.Y + 25), 5, 32, randomRotations[4], Color.Yellow);
-        DrawPoly(new(center.X - 60, center.Y + 75), 5, 32, randomRotations[3], Color.SkyBlue);
-        DrawPoly(new(center.X + 60, center.Y + 75), 5, 32, randomRotations[4], Color.Green);
-        // DrawPoly(new (center.X + 75, center.Y + 25), 5, 32, 0, Color.Orange);
-        DrawFPS(5, 5);
     }
     
+    
     [UnmanagedCallersOnly(CallConvs = [typeof(System.Runtime.CompilerServices.CallConvCdecl)])]
     private static unsafe void RaylibLogHandler(int logLevel_, sbyte* text_, sbyte* args_)
     {