feat: added basic window, input & drawing

Platforms/Desktop/Engine.Integration.SDL3/Sdl3Camera2D.cs

@@ -0,0 +1,86 @@
+using Engine.Core;
+
+namespace Engine.Integration.SDL3;
+
+public class Sdl3Camera2D : Behaviour, ICamera2D, IFirstFrameUpdate, ILastFrameUpdate, IPreDraw
+{
+    public Event<Sdl3Camera2D> OnViewMatrixChanged { get; } = new();
+    public Event<Sdl3Camera2D> OnProjectionMatrixChanged { get; } = new();
+    public Event<Sdl3Camera2D> OnViewportChanged { get; } = new();
+    public Event<Sdl3Camera2D> OnZoomChanged { get; } = new();
+
+    private IWindow window = null!;
+    public ITransform2D Transform { get; private set; } = null!;
+
+    public Matrix4x4 ProjectionMatrix
+    {
+        get;
+        private set
+        {
+            if (field == value)
+                return;
+
+            field = value;
+            OnProjectionMatrixChanged.Invoke(this);
+        }
+    } = Matrix4x4.Identity;
+
+    public Matrix4x4 ViewMatrix
+    {
+        get;
+        private set
+        {
+            if (field == value)
+                return;
+
+            field = value;
+            OnViewMatrixChanged.Invoke(this);
+        }
+    } = Matrix4x4.Identity;
+
+    public float Zoom
+    {
+        get;
+        set
+        {
+            float newValue = Math.Max(0.1f, value);
+
+            if (field == newValue)
+                return;
+
+            field = newValue;
+            OnZoomChanged.Invoke(this);
+        }
+    } = 1f;
+
+    // TODO This causes delay since OnPreDraw calls assuming this is called in in Update 
+    public Vector2D ScreenToWorldPosition(Vector2D screenPosition)
+    {
+        Vector2D worldPosition = Vector2D.Transform(screenPosition, Transform);
+        return worldPosition;
+    }
+
+    public Vector2D WorldToScreenPosition(Vector2D worldPosition)
+    {
+        Vector2D screenPosition = Vector2D.Transform(worldPosition, Transform);
+        return screenPosition;
+    }
+
+    public void LastActiveFrame() => Transform = null!;
+    public void FirstActiveFrame()
+    {
+        window = BehaviourController.UniverseObject.Universe.FindRequiredBehaviour<IWindow>();
+        Transform = BehaviourController.GetRequiredBehaviour<ITransform2D>();
+    }
+
+    public void PreDraw()
+    {
+        ProjectionMatrix = Matrix4x4.CreateOrthographicViewCentered(window.Size.X, window.Size.Y);
+
+        ViewMatrix = Matrix4x4.Identity
+            .ApplyScale(Transform.Scale.X.Max(Transform.Scale.Y))
+            .ApplyScale(Zoom)
+            .ApplyRotationZ(-Transform.Rotation * Math.DegreeToRadian)
+            .ApplyTranslation(new Vector3D(-Transform.Position.X, -Transform.Position.Y, 0f));
+    }
+}