Merge pull request #13986 from 02Naitsirk/display-sr-changes

Implement total SR formula that better correlates with pp
ppy · Sep 15, 2021 · 5c1e1d8 · 5c1e1d8
2 parents 203f1b8 + 5ea1924
commit 5c1e1d8
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Showing 3 changed files with 13 additions and 6 deletions.
diff --git a/osu.Game.Rulesets.Osu.Tests/OsuDifficultyCalculatorTest.cs b/osu.Game.Rulesets.Osu.Tests/OsuDifficultyCalculatorTest.cs
@@ -15,13 +15,13 @@ public class OsuDifficultyCalculatorTest : DifficultyCalculatorTest
     {
         protected override string ResourceAssembly => "osu.Game.Rulesets.Osu";
 
-        [TestCase(6.7568168283591499d, "diffcalc-test")]
-        [TestCase(1.0348244046058293d, "zero-length-sliders")]
+        [TestCase(6.6634445062299665d, "diffcalc-test")]
+        [TestCase(1.0414203870195022d, "zero-length-sliders")]
         public void Test(double expected, string name)
             => base.Test(expected, name);
 
-        [TestCase(8.4783236764532557d, "diffcalc-test")]
-        [TestCase(1.2708532136987165d, "zero-length-sliders")]
+        [TestCase(8.3858089051603368d, "diffcalc-test")]
+        [TestCase(1.2723279173428435d, "zero-length-sliders")]
         public void TestClockRateAdjusted(double expected, string name)
             => Test(expected, name, new OsuModDoubleTime());
 

diff --git a/osu.Game.Rulesets.Osu/Difficulty/OsuDifficultyCalculator.cs b/osu.Game.Rulesets.Osu/Difficulty/OsuDifficultyCalculator.cs
@@ -34,7 +34,11 @@ protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beat
 
             double aimRating = Math.Sqrt(skills[0].DifficultyValue()) * difficulty_multiplier;
             double speedRating = Math.Sqrt(skills[1].DifficultyValue()) * difficulty_multiplier;
-            double starRating = aimRating + speedRating + Math.Abs(aimRating - speedRating) / 2;
+
+            double baseAimPerformance = Math.Pow(5 * Math.Max(1, aimRating / 0.0675) - 4, 3) / 100000;
+            double baseSpeedPerformance = Math.Pow(5 * Math.Max(1, speedRating / 0.0675) - 4, 3) / 100000;
+            double basePerformance = Math.Pow(Math.Pow(baseAimPerformance, 1.1) + Math.Pow(baseSpeedPerformance, 1.1), 1 / 1.1);
+            double starRating = basePerformance > 0.00001 ? Math.Cbrt(1.12) * 0.027 * (Math.Cbrt(100000 / Math.Pow(2, 1 / 1.1) * basePerformance) + 4) : 0;
 
             HitWindows hitWindows = new OsuHitWindows();
             hitWindows.SetDifficulty(beatmap.BeatmapInfo.BaseDifficulty.OverallDifficulty);

diff --git a/osu.Game/Tests/Beatmaps/DifficultyCalculatorTest.cs b/osu.Game/Tests/Beatmaps/DifficultyCalculatorTest.cs
@@ -23,7 +23,10 @@ public abstract class DifficultyCalculatorTest
         protected abstract string ResourceAssembly { get; }
 
         protected void Test(double expected, string name, params Mod[] mods)
-            => Assert.AreEqual(expected, CreateDifficultyCalculator(getBeatmap(name)).Calculate(mods).StarRating);
+        {
+            // Platform-dependent math functions (Pow, Cbrt, Exp, etc) may result in minute differences.
+            Assert.That(CreateDifficultyCalculator(getBeatmap(name)).Calculate(mods).StarRating, Is.EqualTo(expected).Within(0.00001));
+        }
 
         private WorkingBeatmap getBeatmap(string name)
         {