Add interface to adjust Beatmaps

osu.Game/Rulesets/Mods/IApplicableToBeatmap.cs

@@ -0,0 +1,19 @@
+// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using osu.Game.Beatmaps;
+
+namespace osu.Game.Rulesets.Mods
+{
+    /// <summary>
+    /// Interface for a <see cref="Mod"/> that applies changes to a <see cref="Beatmap"/>.
+    /// </summary>
+    public interface IApplicableToBeatmap : IApplicableMod
+    {
+        /// <summary>
+        /// Applies this <see cref="Mod"/> to a <see cref="Beatmap"/>.
+        /// </summary>
+        /// <param name="beatmap">The <see cref="Beatmap"/> to apply to.</param>
+        void ApplyToBeatmap(IBeatmap beatmap);
+    }
+}