Don't punish slider hit windows in difficulty calculations when slider head accuracy is in use

osu.Game.Rulesets.Catch/Difficulty/CatchDifficultyCalculator.cs

@@ -50,7 +50,7 @@ protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beat
             return attributes;
         }
 
-        protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate)
+        protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, Mod[] mods, double clockRate)
         {
             CatchHitObject? lastObject = null;
 

osu.Game.Rulesets.Mania/Difficulty/ManiaDifficultyCalculator.cs

@@ -67,7 +67,7 @@ private static int maxComboForObject(HitObject hitObject)
             return 1;
         }
 
-        protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate)
+        protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, Mod[] mods, double clockRate)
         {
             var sortedObjects = beatmap.HitObjects.ToArray();
 

osu.Game.Rulesets.Osu/Difficulty/Evaluators/RhythmEvaluator.cs

@@ -2,8 +2,12 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Collections.Generic;
+using System.Linq;
 using osu.Game.Rulesets.Difficulty.Preprocessing;
+using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Osu.Difficulty.Preprocessing;
+using osu.Game.Rulesets.Osu.Mods;
 using osu.Game.Rulesets.Osu.Objects;
 
 namespace osu.Game.Rulesets.Osu.Difficulty.Evaluators
@@ -16,7 +20,7 @@ public static class RhythmEvaluator
         /// <summary>
         /// Calculates a rhythm multiplier for the difficulty of the tap associated with historic data of the current <see cref="OsuDifficultyHitObject"/>.
         /// </summary>
-        public static double EvaluateDifficultyOf(DifficultyHitObject current)
+        public static double EvaluateDifficultyOf(DifficultyHitObject current, IReadOnlyList<Mod> mods)
         {
             if (current.BaseObject is Spinner)
                 return 0;
@@ -67,7 +71,7 @@ public static double EvaluateDifficultyOf(DifficultyHitObject current)
                     }
                     else
                     {
-                        if (currObj.BaseObject is Slider) // bpm change is into slider, this is easy acc window
+                        if (currObj.BaseObject is Slider && mods.Any(m => m is OsuModClassic cl && cl.NoSliderHeadAccuracy.Value)) // bpm change is into slider, this is easy acc window without slider head accuracy
                             effectiveRatio *= 0.125;
 
                         if (prevObj.BaseObject is Slider) // bpm change was from a slider, this is easier typically than circle -> circle

osu.Game.Rulesets.Osu/Difficulty/OsuDifficultyCalculator.cs

@@ -113,7 +113,7 @@ protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beat
             return attributes;
         }
 
-        protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate)
+        protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, Mod[] mods, double clockRate)
         {
             List<DifficultyHitObject> objects = new List<DifficultyHitObject>();
 
@@ -122,7 +122,7 @@ protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(I
             for (int i = 1; i < beatmap.HitObjects.Count; i++)
             {
                 var lastLast = i > 1 ? beatmap.HitObjects[i - 2] : null;
-                objects.Add(new OsuDifficultyHitObject(beatmap.HitObjects[i], beatmap.HitObjects[i - 1], lastLast, clockRate, objects, objects.Count));
+                objects.Add(new OsuDifficultyHitObject(beatmap.HitObjects[i], beatmap.HitObjects[i - 1], lastLast, clockRate, objects, objects.Count, mods));
             }
 
             return objects;

osu.Game.Rulesets.Osu/Difficulty/Preprocessing/OsuDifficultyHitObject.cs

@@ -5,6 +5,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using osu.Game.Rulesets.Difficulty.Preprocessing;
+using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Osu.Mods;
 using osu.Game.Rulesets.Osu.Objects;
@@ -86,7 +87,7 @@ public class OsuDifficultyHitObject : DifficultyHitObject
         private readonly OsuHitObject? lastLastObject;
         private readonly OsuHitObject lastObject;
 
-        public OsuDifficultyHitObject(HitObject hitObject, HitObject lastObject, HitObject? lastLastObject, double clockRate, List<DifficultyHitObject> objects, int index)
+        public OsuDifficultyHitObject(HitObject hitObject, HitObject lastObject, HitObject? lastLastObject, double clockRate, List<DifficultyHitObject> objects, int index, IReadOnlyList<Mod> mods)
             : base(hitObject, lastObject, clockRate, objects, index)
         {
             this.lastLastObject = lastLastObject as OsuHitObject;
@@ -95,7 +96,7 @@ public OsuDifficultyHitObject(HitObject hitObject, HitObject lastObject, HitObje
             // Capped to 25ms to prevent difficulty calculation breaking from simultaneous objects.
             StrainTime = Math.Max(DeltaTime, min_delta_time);
 
-            if (BaseObject is Slider sliderObject)
+            if (BaseObject is Slider sliderObject && mods.Any(m => m is OsuModClassic cl && cl.NoSliderHeadAccuracy.Value))
             {
                 HitWindowGreat = 2 * sliderObject.HeadCircle.HitWindows.WindowFor(HitResult.Great) / clockRate;
             }

osu.Game.Rulesets.Osu/Difficulty/Skills/Speed.cs

@@ -41,7 +41,7 @@ protected override double StrainValueAt(DifficultyHitObject current)
             currentStrain *= strainDecay(((OsuDifficultyHitObject)current).StrainTime);
             currentStrain += SpeedEvaluator.EvaluateDifficultyOf(current) * skillMultiplier;
 
-            currentRhythm = RhythmEvaluator.EvaluateDifficultyOf(current);
+            currentRhythm = RhythmEvaluator.EvaluateDifficultyOf(current, Mods);
 
             double totalStrain = currentStrain * currentRhythm;
 

osu.Game.Rulesets.Taiko/Difficulty/TaikoDifficultyCalculator.cs

@@ -46,7 +46,7 @@ protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods, double clo
             new TaikoModHardRock(),
         };
 
-        protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate)
+        protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, Mod[] mods, double clockRate)
         {
             List<DifficultyHitObject> difficultyHitObjects = new List<DifficultyHitObject>();
             List<TaikoDifficultyHitObject> centreObjects = new List<TaikoDifficultyHitObject>();

osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs

@@ -160,7 +160,7 @@ public IEnumerable<DifficultyAttributes> CalculateAllLegacyCombinations(Cancella
         /// <summary>
         /// Retrieves the <see cref="DifficultyHitObject"/>s to calculate against.
         /// </summary>
-        private IEnumerable<DifficultyHitObject> getDifficultyHitObjects() => SortObjects(CreateDifficultyHitObjects(Beatmap, clockRate));
+        private IEnumerable<DifficultyHitObject> getDifficultyHitObjects() => SortObjects(CreateDifficultyHitObjects(Beatmap, playableMods, clockRate));
 
         /// <summary>
         /// Performs required tasks before every calculation.
@@ -277,9 +277,10 @@ static IEnumerable<Mod> createDifficultyAdjustmentModCombinations(ReadOnlyMemory
         /// Enumerates <see cref="DifficultyHitObject"/>s to be processed from <see cref="HitObject"/>s in the <see cref="IBeatmap"/>.
         /// </summary>
         /// <param name="beatmap">The <see cref="IBeatmap"/> providing the <see cref="HitObject"/>s to enumerate.</param>
+        /// <param name="mods">The <see cref="Mod"/>s that difficulty was calculated with.</param>
         /// <param name="clockRate">The rate at which the gameplay clock is run at.</param>
         /// <returns>The enumerated <see cref="DifficultyHitObject"/>s.</returns>
-        protected abstract IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate);
+        protected abstract IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, Mod[] mods, double clockRate);
 
         /// <summary>
         /// Creates the <see cref="Skill"/>s to calculate the difficulty of an <see cref="IBeatmap"/>.