Added Zero, One, Linear and Clamp to Easings

CHANGELOG.md

@@ -16,6 +16,7 @@ Jump to version:
 ### MLEM
 Additions
 - Added GraphicsExtensions.WithRenderTargets, a multi-target version of WithRenderTarget
+- Added Zero, One, Linear and Clamp to Easings
 
 Fixes
 - Fixed TextInput not working correctly when using surrogate pairs

MLEM/Misc/Easings.cs

@@ -1,4 +1,5 @@
 using System;
+using Microsoft.Xna.Framework;
 
 namespace MLEM.Misc {
     /// <summary>
@@ -8,6 +9,21 @@ namespace MLEM.Misc {
     /// </summary>
     public static class Easings {
 
+        /// <summary>
+        /// An easing function that constantly returns 0, regardless of the input percentage.
+        /// This is useful for chaining using <see cref="AndThen(MLEM.Misc.Easings.Easing,MLEM.Misc.Easings.Easing)"/>.
+        /// </summary>
+        public static readonly Easing Zero = p => 0;
+        /// <summary>
+        /// An easing function that constantly returns 1, regardless of the input percentage.
+        /// This is useful for chaining using <see cref="AndThen(MLEM.Misc.Easings.Easing,MLEM.Misc.Easings.Easing)"/>.
+        /// </summary>
+        public static readonly Easing One = p => 1;
+        /// <summary>
+        /// A linear easing function that returns the input percentage without modifying it.
+        /// </summary>
+        public static readonly Easing Linear = p => p;
+
         /// <summary>https://easings.net/#easeInSine</summary>
         public static readonly Easing InSine = p => 1 - (float) Math.Cos(p * Math.PI / 2);
         /// <summary>https://easings.net/#easeOutSine</summary>
@@ -170,6 +186,17 @@ namespace MLEM.Misc {
             };
         }
 
+        /// <summary>
+        /// Causes output from the easing function to be clamped between the <paramref name="min"/> and <paramref name="max"/> values passed.
+        /// </summary>
+        /// <param name="easing">The easing function to clamp.</param>
+        /// <param name="min">The minimum output value to clamp to, defaults to 0.</param>
+        /// <param name="max">The maximum output value to clamp to, defaults to 1.</param>
+        /// <returns>A clamped easing function.</returns>
+        public static Easing Clamp(this Easing easing, float min = 0, float max = 1) {
+            return p => MathHelper.Clamp(easing(p), min, max);
+        }
+
         /// <summary>
         /// A delegate method used by <see cref="Easings"/>.
         /// </summary>