update: expanded Fixed64 operators

Author: mrdav30

src/FixedMathSharp/Numerics/Fixed64.cs

@@ -252,14 +252,30 @@ public static explicit operator decimal(Fixed64 value)
         }
 
         /// <summary>
-        /// Adds an int to y 
+        /// Adds an Fixed64 to x 
         /// </summary>
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static Fixed64 operator +(int x, Fixed64 y)
         {
             return y + x;
         }
 
+        /// <summary>
+        /// Adds a float to x 
+        /// </summary>
+        public static Fixed64 operator +(Fixed64 x, float y)
+        {
+            return new Fixed64((x.m_rawValue * FixedMath.SCALE_FACTOR_D) + y);
+        }
+
+        /// <summary>
+        /// Adds a Fixed64 to x 
+        /// </summary>
+        public static Fixed64 operator +(float x, Fixed64 y)
+        {
+            return y + x;
+        }
+
         /// <summary>
         /// Subtracts one Fixed64 number from another, with saturating behavior in case of overflow.
         /// </summary>
@@ -284,12 +300,30 @@ public static explicit operator decimal(Fixed64 value)
         }
 
         /// <summary>
-        /// Subtracts an int from y 
+        /// Subtracts a Fixed64 from x 
         /// </summary>
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static Fixed64 operator -(int x, Fixed64 y)
         {
-            return y - x;
+            return new Fixed64(x - (y.m_rawValue * FixedMath.SCALE_FACTOR_D));
+        }
+
+        /// <summary>
+        /// Subtracts a float from x 
+        /// </summary>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static Fixed64 operator -(Fixed64 x, float y)
+        {
+            return new Fixed64((x.m_rawValue * FixedMath.SCALE_FACTOR_D) - y);
+        }
+
+        /// <summary>
+        /// Subtracts a Fixed64 from x 
+        /// </summary>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static Fixed64 operator -(float x, Fixed64 y)
+        {
+            return new Fixed64(x - (y.m_rawValue * FixedMath.SCALE_FACTOR_D));
         }
 
         /// <summary>