Merge pull request #26405 from bdach/catch-scoring

Adjust catch scoring to match stable score V2

osu.Game.Rulesets.Catch/Scoring/CatchScoreProcessor.cs

@@ -2,6 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Collections.Generic;
 using osu.Game.Rulesets.Judgements;
 using osu.Game.Rulesets.Scoring;
 using osu.Game.Scoring;
@@ -20,20 +21,73 @@ namespace osu.Game.Rulesets.Catch.Scoring
         private const int combo_cap = 200;
         private const double combo_base = 4;
 
+        private double fruitTinyScale;
+
         public CatchScoreProcessor()
             : base(new CatchRuleset())
         {
         }
 
+        protected override void Reset(bool storeResults)
+        {
+            base.Reset(storeResults);
+
+            // large ticks are *purposefully* not counted to match stable
+            int fruitTinyScaleDivisor = MaximumResultCounts.GetValueOrDefault(HitResult.SmallTickHit) + MaximumResultCounts.GetValueOrDefault(HitResult.Great);
+            fruitTinyScale = fruitTinyScaleDivisor == 0
+                ? 0
+                : (double)MaximumResultCounts.GetValueOrDefault(HitResult.SmallTickHit) / fruitTinyScaleDivisor;
+        }
+
         protected override double ComputeTotalScore(double comboProgress, double accuracyProgress, double bonusPortion)
         {
-            return 600000 * comboProgress
-                   + 400000 * Accuracy.Value * accuracyProgress
+            const int max_tiny_droplets_portion = 400000;
+
+            double comboPortion = 1000000 - max_tiny_droplets_portion + max_tiny_droplets_portion * (1 - fruitTinyScale);
+            double dropletsPortion = max_tiny_droplets_portion * fruitTinyScale;
+            double dropletsHit = MaximumResultCounts.GetValueOrDefault(HitResult.SmallTickHit) == 0
+                ? 0
+                : (double)ScoreResultCounts.GetValueOrDefault(HitResult.SmallTickHit) / MaximumResultCounts.GetValueOrDefault(HitResult.SmallTickHit);
+
+            return comboPortion * comboProgress
+                   + dropletsPortion * dropletsHit
                    + bonusPortion;
         }
 
+        public override int GetBaseScoreForResult(HitResult result)
+        {
+            switch (result)
+            {
+                // dirty hack to emulate accuracy on stable weighting every object equally in accuracy portion
+                case HitResult.Great:
+                case HitResult.LargeTickHit:
+                case HitResult.SmallTickHit:
+                    return 300;
+
+                case HitResult.LargeBonus:
+                    return 200;
+            }
+
+            return base.GetBaseScoreForResult(result);
+        }
+
         protected override double GetComboScoreChange(JudgementResult result)
-            => GetBaseScoreForResult(result.Type) * Math.Min(Math.Max(0.5, Math.Log(result.ComboAfterJudgement, combo_base)), Math.Log(combo_cap, combo_base));
+        {
+            double baseIncrease = 0;
+
+            switch (result.Type)
+            {
+                case HitResult.Great:
+                    baseIncrease = 300;
+                    break;
+
+                case HitResult.LargeTickHit:
+                    baseIncrease = 100;
+                    break;
+            }
+
+            return baseIncrease * Math.Min(Math.Max(0.5, Math.Log(result.ComboAfterJudgement, combo_base)), Math.Log(combo_cap, combo_base));
+        }
 
         public override ScoreRank RankFromAccuracy(double accuracy)
         {

osu.Game/Database/StandardisedScoreMigrationTools.cs

@@ -446,9 +446,30 @@ namespace osu.Game.Database
                     break;
 
                 case 2:
+                    // compare logic in `CatchScoreProcessor`.
+
+                    // this could technically be slightly incorrect in the case of stable scores.
+                    // because large droplet misses are counted as full misses in stable scores,
+                    // `score.MaximumStatistics.GetValueOrDefault(Great)` will be equal to the count of fruits *and* large droplets
+                    // rather than just fruits (which was the intent).
+                    // this is not fixable without introducing an extra legacy score attribute dedicated for catch,
+                    // and this is a ballpark conversion process anyway, so attempt to trudge on.
+                    int fruitTinyScaleDivisor = score.MaximumStatistics.GetValueOrDefault(HitResult.SmallTickHit) + score.MaximumStatistics.GetValueOrDefault(HitResult.Great);
+                    double fruitTinyScale = fruitTinyScaleDivisor == 0
+                        ? 0
+                        : (double)score.MaximumStatistics.GetValueOrDefault(HitResult.SmallTickHit) / fruitTinyScaleDivisor;
+
+                    const int max_tiny_droplets_portion = 400000;
+
+                    double comboPortion = 1000000 - max_tiny_droplets_portion + max_tiny_droplets_portion * (1 - fruitTinyScale);
+                    double dropletsPortion = max_tiny_droplets_portion * fruitTinyScale;
+                    double dropletsHit = score.MaximumStatistics.GetValueOrDefault(HitResult.SmallTickHit) == 0
+                        ? 0
+                        : (double)score.Statistics.GetValueOrDefault(HitResult.SmallTickHit) / score.MaximumStatistics.GetValueOrDefault(HitResult.SmallTickHit);
+
                     convertedTotalScore = (long)Math.Round((
-                        600000 * comboProportion
-                        + 400000 * score.Accuracy
+                        comboPortion * estimateComboProportionForCatch(attributes.MaxCombo, score.MaxCombo, score.Statistics.GetValueOrDefault(HitResult.Miss))
+                        + dropletsPortion * dropletsHit
                         + bonusProportion) * modMultiplier);
                     break;
 
@@ -475,6 +496,94 @@ namespace osu.Game.Database
             return convertedTotalScore;
         }
 
+        /// <summary>
+        /// <para>
+        /// For catch, the general method of calculating the combo proportion used for other rulesets is generally useless.
+        /// This is because in stable score V1, catch has quadratic score progression,
+        /// while in stable score V2, score progression is logarithmic up to 200 combo and then linear.
+        /// </para>
+        /// <para>
+        /// This means that applying the naive rescale method to scores with lots of short combos (think 10x 100-long combos on a 1000-object map)
+        /// by linearly rescaling the combo portion as given by score V1 leads to horribly underestimating it.
+        /// Therefore this method attempts to counteract this by calculating the best case estimate for the combo proportion that takes all of the above into account.
+        /// </para>
+        /// <para>
+        /// The general idea is that aside from the <paramref name="scoreMaxCombo"/> which the player is known to have hit,
+        /// the remaining misses are evenly distributed across the rest of the objects that give combo.
+        /// This is therefore a worst-case estimate.
+        /// </para>
+        /// </summary>
+        private static double estimateComboProportionForCatch(int beatmapMaxCombo, int scoreMaxCombo, int scoreMissCount)
+        {
+            if (beatmapMaxCombo == 0)
+                return 1;
+
+            if (scoreMaxCombo == 0)
+                return 0;
+
+            if (beatmapMaxCombo == scoreMaxCombo)
+                return 1;
+
+            double estimatedBestCaseTotal = estimateBestCaseComboTotal(beatmapMaxCombo);
+
+            int remainingCombo = beatmapMaxCombo - (scoreMaxCombo + scoreMissCount);
+            double totalDroppedScore = 0;
+
+            int assumedLengthOfRemainingCombos = (int)Math.Floor((double)remainingCombo / scoreMissCount);
+
+            if (assumedLengthOfRemainingCombos > 0)
+            {
+                int assumedCombosCount = (int)Math.Floor((double)remainingCombo / assumedLengthOfRemainingCombos);
+                totalDroppedScore += assumedCombosCount * estimateDroppedComboScoreAfterMiss(assumedLengthOfRemainingCombos);
+
+                remainingCombo -= assumedCombosCount * assumedLengthOfRemainingCombos;
+
+                if (remainingCombo > 0)
+                    totalDroppedScore += estimateDroppedComboScoreAfterMiss(remainingCombo);
+            }
+            else
+            {
+                // there are so many misses that attempting to evenly divide remaining combo results in 0 length per combo,
+                // i.e. all remaining judgements are combo breaks.
+                // in that case, presume every single remaining object is a miss and did not give any combo score.
+                totalDroppedScore = estimatedBestCaseTotal - estimateBestCaseComboTotal(scoreMaxCombo);
+            }
+
+            return estimatedBestCaseTotal == 0
+                ? 1
+                : 1 - Math.Clamp(totalDroppedScore / estimatedBestCaseTotal, 0, 1);
+
+            double estimateBestCaseComboTotal(int maxCombo)
+            {
+                if (maxCombo == 0)
+                    return 1;
+
+                double estimatedTotal = 0.5 * Math.Min(maxCombo, 2);
+
+                if (maxCombo <= 2)
+                    return estimatedTotal;
+
+                // int_2^x log_4(t) dt
+                estimatedTotal += (Math.Min(maxCombo, 200) * (Math.Log(Math.Min(maxCombo, 200)) - 1) + 2 - Math.Log(4)) / Math.Log(4);
+
+                if (maxCombo <= 200)
+                    return estimatedTotal;
+
+                estimatedTotal += (maxCombo - 200) * Math.Log(200) / Math.Log(4);
+                return estimatedTotal;
+            }
+
+            double estimateDroppedComboScoreAfterMiss(int lengthOfComboAfterMiss)
+            {
+                if (lengthOfComboAfterMiss >= 200)
+                    lengthOfComboAfterMiss = 200;
+
+                // int_0^x (log_4(200) - log_4(t)) dt
+                // note that this is an pessimistic estimate, i.e. it may subtract too much if the miss happened before reaching 200 combo
+                return lengthOfComboAfterMiss * (1 + Math.Log(200) - Math.Log(lengthOfComboAfterMiss)) / Math.Log(4);
+            }
+        }
+
         public static double ComputeAccuracy(ScoreInfo scoreInfo)
         {
             Ruleset ruleset = scoreInfo.Ruleset.CreateInstance();

osu.Game/Rulesets/Scoring/ScoreProcessor.cs

@@ -169,14 +169,14 @@ namespace osu.Game.Rulesets.Scoring
                 if (!beatmapApplied)
                     throw new InvalidOperationException($"Cannot access maximum statistics before calling {nameof(ApplyBeatmap)}.");
 
-                return new Dictionary<HitResult, int>(maximumResultCounts);
+                return new Dictionary<HitResult, int>(MaximumResultCounts);
             }
         }
 
         private bool beatmapApplied;
 
-        private readonly Dictionary<HitResult, int> scoreResultCounts = new Dictionary<HitResult, int>();
-        private readonly Dictionary<HitResult, int> maximumResultCounts = new Dictionary<HitResult, int>();
+        protected readonly Dictionary<HitResult, int> ScoreResultCounts = new Dictionary<HitResult, int>();
+        protected readonly Dictionary<HitResult, int> MaximumResultCounts = new Dictionary<HitResult, int>();
 
         private readonly List<HitEvent> hitEvents = new List<HitEvent>();
         private HitObject? lastHitObject;
@@ -222,7 +222,7 @@ namespace osu.Game.Rulesets.Scoring
             if (result.FailedAtJudgement)
                 return;
 
-            scoreResultCounts[result.Type] = scoreResultCounts.GetValueOrDefault(result.Type) + 1;
+            ScoreResultCounts[result.Type] = ScoreResultCounts.GetValueOrDefault(result.Type) + 1;
 
             if (result.Type.IncreasesCombo())
                 Combo.Value++;
@@ -278,7 +278,7 @@ namespace osu.Game.Rulesets.Scoring
             if (result.FailedAtJudgement)
                 return;
 
-            scoreResultCounts[result.Type] = scoreResultCounts.GetValueOrDefault(result.Type) - 1;
+            ScoreResultCounts[result.Type] = ScoreResultCounts.GetValueOrDefault(result.Type) - 1;
 
             if (result.Judgement.MaxResult.AffectsAccuracy())
             {
@@ -400,13 +400,13 @@ namespace osu.Game.Rulesets.Scoring
                 maximumComboPortion = currentComboPortion;
                 maximumAccuracyJudgementCount = currentAccuracyJudgementCount;
 
-                maximumResultCounts.Clear();
-                maximumResultCounts.AddRange(scoreResultCounts);
+                MaximumResultCounts.Clear();
+                MaximumResultCounts.AddRange(ScoreResultCounts);
 
                 MaximumTotalScore = TotalScore.Value;
             }
 
-            scoreResultCounts.Clear();
+            ScoreResultCounts.Clear();
 
             currentBaseScore = 0;
             currentMaximumBaseScore = 0;
@@ -435,10 +435,10 @@ namespace osu.Game.Rulesets.Scoring
             score.MaximumStatistics.Clear();
 
             foreach (var result in HitResultExtensions.ALL_TYPES)
-                score.Statistics[result] = scoreResultCounts.GetValueOrDefault(result);
+                score.Statistics[result] = ScoreResultCounts.GetValueOrDefault(result);
 
             foreach (var result in HitResultExtensions.ALL_TYPES)
-                score.MaximumStatistics[result] = maximumResultCounts.GetValueOrDefault(result);
+                score.MaximumStatistics[result] = MaximumResultCounts.GetValueOrDefault(result);
 
             // Populate total score after everything else.
             score.TotalScore = TotalScore.Value;
@@ -469,8 +469,8 @@ namespace osu.Game.Rulesets.Scoring
             HighestCombo.Value = frame.Header.MaxCombo;
             TotalScore.Value = frame.Header.TotalScore;
 
-            scoreResultCounts.Clear();
-            scoreResultCounts.AddRange(frame.Header.Statistics);
+            ScoreResultCounts.Clear();
+            ScoreResultCounts.AddRange(frame.Header.Statistics);
 
             SetScoreProcessorStatistics(frame.Header.ScoreProcessorStatistics);
 

osu.Game/Scoring/Legacy/LegacyScoreEncoder.cs

@@ -37,9 +37,10 @@ namespace osu.Game.Scoring.Legacy
         /// <item><description>30000008: Add accuracy conversion. Reconvert all scores.</description></item>
         /// <item><description>30000009: Fix edge cases in conversion for scores which have 0.0x mod multiplier on stable. Reconvert all scores.</description></item>
         /// <item><description>30000010: Fix mania score V1 conversion using score V1 accuracy rather than V2 accuracy. Reconvert all scores.</description></item>
+        /// <item><description>30000011: Re-do catch scoring to mirror stable Score V2 as closely as feasible. Reconvert all scores.</description></item>
         /// </list>
         /// </remarks>
-        public const int LATEST_VERSION = 30000010;
+        public const int LATEST_VERSION = 30000011;
 
         /// <summary>
         /// The first stable-compatible YYYYMMDD format version given to lazer usage of replays.