From 28e006eeb9f806e8cc41653df295fef4f17ac3ac Mon Sep 17 00:00:00 2001
From: smoogipooo <smoogipooo@gmail.com>
Date: Thu, 16 Mar 2017 23:17:27 +0900
Subject: [PATCH] Move MapDifficultyRange into BaseDifficulty.

---
 osu.Game/Database/BaseDifficulty.cs | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/osu.Game/Database/BaseDifficulty.cs b/osu.Game/Database/BaseDifficulty.cs
index 83f6e2fdd5..ea7511315f 100644
--- a/osu.Game/Database/BaseDifficulty.cs
+++ b/osu.Game/Database/BaseDifficulty.cs
@@ -15,6 +15,23 @@ namespace osu.Game.Database
         public float ApproachRate { get; set; }
         public float SliderMultiplier { get; set; }
         public float SliderTickRate { get; set; }
+
+        /// <summary>
+        /// Maps a difficulty value [0, 10] to a two-piece linear range of values.
+        /// </summary>
+        /// <param name="difficulty">The difficulty value to be mapped.</param>
+        /// <param name="min">Minimum of the resulting range which will be achieved by a difficulty value of 0.</param>
+        /// <param name="mid">Midpoint of the resulting range which will be achieved by a difficulty value of 5.</param>
+        /// <param name="max">Maximum of the resulting range which will be achieved by a difficulty value of 10.</param>
+        /// <returns>Value to which the difficulty value maps in the specified range.</returns>
+        public static double DifficultyRange(double difficulty, double min, double mid, double max)
+        {
+            if (difficulty > 5)
+                return mid + (max - mid) * (difficulty - 5) / 5;
+            if (difficulty < 5)
+                return mid - (mid - min) * (5 - difficulty) / 5;
+            return mid;
+        }
     }
 }