gl viewport

NResUI/Rendering/Viewport/ViewportCamera.cs

@@ -0,0 +1,38 @@
+using System.Numerics;
+
+namespace NResUI.Rendering.Viewport;
+
+public sealed class ViewportCamera
+{
+    public float YawDegrees { get; set; } = 35.0f;
+    public float PitchDegrees { get; set; } = 25.0f;
+    public float Distance { get; set; } = 4.0f;
+
+    public Matrix4x4 GetSceneRotationMatrix()
+    {
+        return Matrix4x4.CreateRotationY(ToRadians(YawDegrees)) *
+               Matrix4x4.CreateRotationX(ToRadians(PitchDegrees));
+    }
+
+    public Matrix4x4 GetViewMatrix()
+    {
+        return Matrix4x4.CreateLookAt(
+            new Vector3(0.0f, 0.0f, Distance),
+            Vector3.Zero,
+            Vector3.UnitY);
+    }
+
+    public Matrix4x4 GetProjectionMatrix(float aspectRatio)
+    {
+        return Matrix4x4.CreatePerspectiveFieldOfView(
+            ToRadians(60.0f),
+            aspectRatio,
+            0.01f,
+            100.0f);
+    }
+
+    public static float ToRadians(float degrees)
+    {
+        return degrees * MathF.PI / 180.0f;
+    }
+}