chore,gd: refactored project structure and started the mantle system

player_controller/Scripts/FieldOfView.cs

@@ -0,0 +1,44 @@
+using Godot;
+
+namespace PolarBears.PlayerControllerAddon;
+
+public partial class FieldOfView: Node3D
+{
+    [Export(PropertyHint.Range, "0,180,0.1,degrees")]
+    public float BaseFov         { get; set; } = 75.0f;
+    [Export(PropertyHint.Range, "0,10,0.01,or_greater")]
+    public float FovChangeFactor { get; set; } = 1.2f;
+    [Export(PropertyHint.Range, "0,10,0.01,or_greater")]
+    public float FovChangeSpeed  { get; set; } = 6.25f;
+    
+    private Camera3D _camera;
+
+    public void Init(Camera3D cam)
+    {
+        _camera = cam;
+    }
+
+    public struct FovParameters
+    {
+        public bool IsCrouchingHeight;
+        public float Delta;
+        public float SprintSpeed;
+        public Vector3 Velocity;
+    }
+    
+    public void PerformFovAdjustment(FovParameters parameters)
+    {
+        float velocityClamped = Mathf.Clamp(
+            Mathf.Abs(parameters.Velocity.X) + Mathf.Abs(parameters.Velocity.Z), 
+            0.5f, 
+            parameters.SprintSpeed * 2.0f);
+
+        float targetFov = BaseFov + FovChangeFactor * velocityClamped;
+			
+        if (parameters.IsCrouchingHeight){
+            targetFov = BaseFov - FovChangeFactor  * velocityClamped;
+        }
+
+        _camera.Fov = Mathf.Lerp(_camera.Fov, targetFov, parameters.Delta * FovChangeSpeed);
+    }
+}