Allow "Difficulty Adjust" mod's extended AR selection to go below zero

osu.Game.Rulesets.Osu/Mods/OsuModDifficultyAdjust.cs

@@ -2,13 +2,19 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System.Linq;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Framework.Localisation;
 using osu.Game.Beatmaps;
+using osu.Game.Beatmaps.ControlPoints;
 using osu.Game.Configuration;
+using osu.Game.Graphics.UserInterface;
 using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Osu.Objects;
 
 namespace osu.Game.Rulesets.Osu.Mods
 {
-    public class OsuModDifficultyAdjust : ModDifficultyAdjust
+    public partial class OsuModDifficultyAdjust : ModDifficultyAdjust
     {
         [SettingSource("Circle Size", "Override a beatmap's set CS.", FIRST_SETTING_ORDER - 1, SettingControlType = typeof(DifficultyAdjustSettingsControl))]
         public DifficultyBindable CircleSize { get; } = new DifficultyBindable
@@ -20,12 +26,13 @@ public class OsuModDifficultyAdjust : ModDifficultyAdjust
             ReadCurrentFromDifficulty = diff => diff.CircleSize,
         };
 
-        [SettingSource("Approach Rate", "Override a beatmap's set AR.", LAST_SETTING_ORDER + 1, SettingControlType = typeof(DifficultyAdjustSettingsControl))]
+        [SettingSource("Approach Rate", "Override a beatmap's set AR.", LAST_SETTING_ORDER + 1, SettingControlType = typeof(ApproachRateSettingsControl))]
         public DifficultyBindable ApproachRate { get; } = new DifficultyBindable
         {
             Precision = 0.1f,
             MinValue = 0,
             MaxValue = 10,
+            ExtendedMinValue = -10,
             ExtendedMaxValue = 11,
             ReadCurrentFromDifficulty = diff => diff.ApproachRate,
         };
@@ -53,5 +60,34 @@ protected override void ApplySettings(BeatmapDifficulty difficulty)
             if (CircleSize.Value != null) difficulty.CircleSize = CircleSize.Value.Value;
             if (ApproachRate.Value != null) difficulty.ApproachRate = ApproachRate.Value.Value;
         }
+
+        private partial class ApproachRateSettingsControl : DifficultyAdjustSettingsControl
+        {
+            protected override RoundedSliderBar<float> CreateSlider(BindableNumber<float> current) =>
+                new ApproachRateSlider
+                {
+                    RelativeSizeAxes = Axes.X,
+                    Current = current,
+                    KeyboardStep = 0.1f,
+                };
+
+            /// <summary>
+            /// A slider bar with more detailed approach rate info for its given value
+            /// </summary>
+            public partial class ApproachRateSlider : RoundedSliderBar<float>
+            {
+                public override LocalisableString TooltipText =>
+                    (Current as BindableNumber<float>)?.MinValue < 0
+                        ? $"{base.TooltipText} ({getPreemptTime(Current.Value):0} ms)"
+                        : base.TooltipText;
+
+                private double getPreemptTime(float approachRate)
+                {
+                    var hitCircle = new HitCircle();
+                    hitCircle.ApplyDefaults(new ControlPointInfo(), new BeatmapDifficulty { ApproachRate = approachRate });
+                    return hitCircle.TimePreempt;
+                }
+            }
+        }
     }
 }

osu.Game/Rulesets/Mods/DifficultyAdjustSettingsControl.cs

@@ -29,7 +29,14 @@ public partial class DifficultyAdjustSettingsControl : SettingsItem<float?>
         /// </remarks>
         private readonly BindableNumber<float> sliderDisplayCurrent = new BindableNumber<float>();
 
-        protected override Drawable CreateControl() => new SliderControl(sliderDisplayCurrent);
+        protected sealed override Drawable CreateControl() => new SliderControl(sliderDisplayCurrent, CreateSlider);
+
+        protected virtual RoundedSliderBar<float> CreateSlider(BindableNumber<float> current) => new RoundedSliderBar<float>
+        {
+            RelativeSizeAxes = Axes.X,
+            Current = current,
+            KeyboardStep = 0.1f,
+        };
 
         /// <summary>
         /// Guards against beatmap values displayed on slider bars being transferred to user override.
@@ -100,16 +107,11 @@ private partial class SliderControl : CompositeDrawable, IHasCurrentValue<float?
                 set => current.Current = value;
             }
 
-            public SliderControl(BindableNumber<float> currentNumber)
+            public SliderControl(BindableNumber<float> currentNumber, Func<BindableNumber<float>, RoundedSliderBar<float>> createSlider)
             {
                 InternalChildren = new Drawable[]
                 {
-                    new RoundedSliderBar<float>
-                    {
-                        RelativeSizeAxes = Axes.X,
-                        Current = currentNumber,
-                        KeyboardStep = 0.1f,
-                    }
+                    createSlider(currentNumber)
                 };
 
                 AutoSizeAxes = Axes.Y;

osu.Game/Rulesets/Mods/DifficultyBindable.cs

@@ -34,9 +34,18 @@ public float Precision
             set => CurrentNumber.Precision = value;
         }
 
+        private float minValue;
+
         public float MinValue
         {
-            set => CurrentNumber.MinValue = value;
+            set
+            {
+                if (value == minValue)
+                    return;
+
+                minValue = value;
+                updateExtents();
+            }
         }
 
         private float maxValue;
@@ -49,7 +58,24 @@ public float MaxValue
                     return;
 
                 maxValue = value;
-                updateMaxValue();
+                updateExtents();
+            }
+        }
+
+        private float? extendedMinValue;
+
+        /// <summary>
+        /// The minimum value to be used when extended limits are applied.
+        /// </summary>
+        public float? ExtendedMinValue
+        {
+            set
+            {
+                if (value == extendedMinValue)
+                    return;
+
+                extendedMinValue = value;
+                updateExtents();
             }
         }
 
@@ -66,7 +92,7 @@ public float MaxValue
                     return;
 
                 extendedMaxValue = value;
-                updateMaxValue();
+                updateExtents();
             }
         }
 
@@ -78,7 +104,7 @@ public DifficultyBindable()
         public DifficultyBindable(float? defaultValue = null)
             : base(defaultValue)
         {
-            ExtendedLimits.BindValueChanged(_ => updateMaxValue());
+            ExtendedLimits.BindValueChanged(_ => updateExtents());
         }
 
         public override float? Value
@@ -94,8 +120,9 @@ public DifficultyBindable(float? defaultValue = null)
             }
         }
 
-        private void updateMaxValue()
+        private void updateExtents()
         {
+            CurrentNumber.MinValue = ExtendedLimits.Value && extendedMinValue != null ? extendedMinValue.Value : minValue;
             CurrentNumber.MaxValue = ExtendedLimits.Value && extendedMaxValue != null ? extendedMaxValue.Value : maxValue;
         }