refactor: Rename stuff.

Source/Visuals/Extensions/Vector3Extensions.cs

@@ -1,23 +1,27 @@
 using System;
 using Godot;
 
-namespace GoDough.Visuals.Extensions {
-  public static class Vector3Extensions {
+namespace GoDough.Visuals.Extensions
+{
+  public static class Vector3Extensions
+  {
 
     public static Vector3 CopyWith(
       this Vector3 source,
-      Nullable<float> x,
+      Nullable<float> x = null,
       Nullable<float> y = null,
-      Nullable<float> z = null) {
+      Nullable<float> z = null)
+    {
       return new Vector3(
         x ?? source.X,
         y ?? source.Y,
         z ?? source.Z);
     }
 
-     public static Vector3 Copy(
-      this Vector3 source) {
-      return source.CopyWith(null);
+    public static Vector3 Copy(
+     this Vector3 source)
+    {
+      return source.CopyWith();
     }
   }
 }