Added useful maths function to the .Net API

NuakeNet/src/Math.cs

@@ -1,10 +1,87 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Numerics;
 using System.Text;
 using System.Threading.Tasks;
 
 namespace Nuake.Net
 {
+    public class Maths
+    {
+        public static float AngleRepeat(float value, float max)
+        {
+            return (value % max + max) % max;
+        }
+
+        /// <summary>
+        /// Lerps euler angles and prevents flipping.
+        /// </summary>
+        /// <param name="from"></param>
+        /// <param name="to"></param>
+        /// <param name="t"></param>
+        /// <returns></returns>
+        public static float LerpAngle(float from, float to, float t)
+        {
+            float delta = AngleRepeat(to - from, 360f);
+            if (delta > 180f)
+            {
+                delta -= 360f;
+            }
+            return from + delta * Math.Max(0f, Math.Min(1f, t));
+        }
+
+        /// <summary>
+        /// Normalize a 3D vector but if the length of the input vector is 0, then the return vector is of length 0.
+        /// </summary>
+        /// <param name="v"></param>
+        /// <returns></returns>
+        public static Vector3 NormalizeSafe(Vector3 v)
+        {
+            if (v.LengthSquared() == 0.0)
+                return new Vector3();
+            return Vector3.Normalize(v);
+        }
+
+        /// <summary>
+        /// Normalize a 2D vector but if the length of the input vector is 0, then the return vector is of length 0.
+        /// </summary>
+        /// <param name="v"></param>
+        /// <returns></returns>
+        public static Vector2 NormalizeSafe(Vector2 v)
+        {
+            if (v.LengthSquared() == 0.0)
+                return new Vector2();
+            return Vector2.Normalize(v);
+        }
+
+
+        /// <summary>
+        /// Normalize a 3D vector, and sets the Y component to 0. If the input length of the input vector is zero, then the return vector is of length 0.
+        /// </summary>
+        /// <param name="v"></param>
+        /// <returns></returns>
+        public static Vector3 NormalizeSafe2D(Vector3 v)
+        {
+            v.Y = 0f;
+            if (v.LengthSquared() == 0.0)
+                return new Vector3();
+
+            return Vector3.Normalize(v);
+        }
+
+
+        /// <summary>
+        /// Returns the length of a 3D vector taking only the X & Z components into account.
+        /// </summary>
+        /// <param name="input"></param>
+        /// <returns></returns>
+        private float Length2D(Vector3 input)
+        {
+            input.Y = 0;
+            return input.Length();
+        }
+    }
+
     
 }