Nerf repeated angles in Flashlight skill

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

@@ -18,11 +18,14 @@ public static class FlashlightEvaluator
         private const double min_velocity = 0.5;
         private const double slider_multiplier = 1.3;
 
+        private const double min_angle_multiplier = 0.2;
+
         /// <summary>
         /// Evaluates the difficulty of memorising and hitting an object, based on:
         /// <list type="bullet">
         /// <item><description>distance between a number of previous objects and the current object,</description></item>
         /// <item><description>the visual opacity of the current object,</description></item>
+        /// <item><description>the angle made by the current object,</description></item>
         /// <item><description>length and speed of the current object (for sliders),</description></item>
         /// <item><description>and whether the hidden mod is enabled.</description></item>
         /// </list>
@@ -43,6 +46,8 @@ public static double EvaluateDifficultyOf(DifficultyHitObject current, bool hidd
 
             OsuDifficultyHitObject lastObj = osuCurrent;
 
+            double angleRepeatCount = 0.0;
+
             // This is iterating backwards in time from the current object.
             for (int i = 0; i < Math.Min(current.Index, 10); i++)
             {
@@ -66,6 +71,13 @@ public static double EvaluateDifficultyOf(DifficultyHitObject current, bool hidd
                     double opacityBonus = 1.0 + max_opacity_bonus * (1.0 - osuCurrent.OpacityAt(currentHitObject.StartTime, hidden));
 
                     result += stackNerf * opacityBonus * scalingFactor * jumpDistance / cumulativeStrainTime;
+
+                    if (currentObj.Angle != null && osuCurrent.Angle != null)
+                    {
+                        // Objects further back in time should count less for the nerf.
+                        if (Math.Abs(currentObj.Angle.Value - osuCurrent.Angle.Value) < 0.02)
+                            angleRepeatCount += Math.Max(1.0 - 0.1 * i, 0.0);
+                    }
                 }
 
                 lastObj = currentObj;
@@ -77,6 +89,9 @@ public static double EvaluateDifficultyOf(DifficultyHitObject current, bool hidd
             if (hidden)
                 result *= 1.0 + hidden_bonus;
 
+            // Nerf patterns with repeated angles.
+            result *= min_angle_multiplier + (1.0 - min_angle_multiplier) / (angleRepeatCount + 1.0);
+
             double sliderBonus = 0.0;
 
             if (osuCurrent.BaseObject is Slider osuSlider)

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

@@ -26,7 +26,7 @@ public Flashlight(Mod[] mods)
             hasHiddenMod = mods.Any(m => m is OsuModHidden);
         }
 
-        private double skillMultiplier => 0.05;
+        private double skillMultiplier => 0.052;
         private double strainDecayBase => 0.15;
 
         private double currentStrain;