Merge pull request #2876 from smoogipoo/more-mania-conversion-fixes

Fix more instances of osu!mania beatmap conversion failing

osu.Game.Rulesets.Mania.Tests/ManiaBeatmapConversionTest.cs

@@ -5,6 +5,8 @@ using System;
 using System.Collections.Generic;
 using NUnit.Framework;
 using osu.Framework.MathUtils;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Mania.Beatmaps;
 using osu.Game.Rulesets.Mania.Objects;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Types;
@@ -13,11 +15,10 @@ using osu.Game.Tests.Beatmaps;
 namespace osu.Game.Rulesets.Mania.Tests
 {
     [TestFixture]
-    public class ManiaBeatmapConversionTest : BeatmapConversionTest<ConvertValue>
+    public class ManiaBeatmapConversionTest : BeatmapConversionTest<ManiaConvertMapping, ConvertValue>
     {
         protected override string ResourceAssembly => "osu.Game.Rulesets.Mania";
 
-        [NonParallelizable]
         [TestCase("basic")]
         public new void Test(string name)
         {
@@ -34,9 +35,35 @@ namespace osu.Game.Rulesets.Mania.Tests
             };
         }
 
+        protected override ManiaConvertMapping CreateConvertMapping() => new ManiaConvertMapping(Converter);
+
         protected override Ruleset CreateRuleset() => new ManiaRuleset();
     }
 
+     public class ManiaConvertMapping : ConvertMapping<ConvertValue>, IEquatable<ManiaConvertMapping>
+     {
+         public uint RandomW;
+         public uint RandomX;
+         public uint RandomY;
+         public uint RandomZ;
+
+         public ManiaConvertMapping()
+         {
+         }
+
+         public ManiaConvertMapping(IBeatmapConverter converter)
+         {
+             var maniaConverter = (ManiaBeatmapConverter)converter;
+             RandomW = maniaConverter.Random.W;
+             RandomX = maniaConverter.Random.X;
+             RandomY = maniaConverter.Random.Y;
+             RandomZ = maniaConverter.Random.Z;
+         }
+
+         public bool Equals(ManiaConvertMapping other) => other != null && RandomW == other.RandomW && RandomX == other.RandomX && RandomY == other.RandomY && RandomZ == other.RandomZ;
+         public override bool Equals(ConvertMapping<ConvertValue> other) => base.Equals(other) && Equals(other as ManiaConvertMapping);
+     }
+
     public struct ConvertValue : IEquatable<ConvertValue>
     {
         /// <summary>

osu.Game.Rulesets.Mania/Beatmaps/ManiaBeatmapConverter.cs

@@ -5,6 +5,7 @@ using osu.Game.Rulesets.Mania.Objects;
 using System;
 using System.Linq;
 using System.Collections.Generic;
+using osu.Framework.MathUtils;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Types;
@@ -28,8 +29,10 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
         public int TargetColumns;
         public readonly bool IsForCurrentRuleset;
 
+        // Internal for testing purposes
+        internal FastRandom Random { get; private set; }
+
         private Pattern lastPattern = new Pattern();
-        private FastRandom random;
 
         private ManiaBeatmap beatmap;
 
@@ -62,7 +65,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
             BeatmapDifficulty difficulty = original.BeatmapInfo.BaseDifficulty;
 
             int seed = (int)Math.Round(difficulty.DrainRate + difficulty.CircleSize) * 20 + (int)(difficulty.OverallDifficulty * 41.2) + (int)Math.Round(difficulty.ApproachRate);
-            random = new FastRandom(seed);
+            Random = new FastRandom(seed);
 
             return base.ConvertBeatmap(original);
         }
@@ -100,7 +103,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
 
         private double lastTime;
         private Vector2 lastPosition;
-        private PatternType lastStair;
+        private PatternType lastStair = PatternType.Stair;
         private void recordNote(double time, Vector2 position)
         {
             lastTime = time;
@@ -115,12 +118,15 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
         /// <returns>The hit objects generated.</returns>
         private IEnumerable<ManiaHitObject> generateSpecific(HitObject original, IBeatmap originalBeatmap)
         {
-            var generator = new SpecificBeatmapPatternGenerator(random, original, beatmap, lastPattern, originalBeatmap);
+            var generator = new SpecificBeatmapPatternGenerator(Random, original, beatmap, lastPattern, originalBeatmap);
 
-            Pattern newPattern = generator.Generate();
-            lastPattern = newPattern;
+            foreach (var newPattern in generator.Generate())
+            {
+                lastPattern = newPattern;
 
-            return newPattern.HitObjects;
+                foreach (var obj in newPattern.HitObjects)
+                    yield return obj;
+            }
         }
 
         /// <summary>
@@ -138,27 +144,44 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
             Patterns.PatternGenerator conversion = null;
 
             if (distanceData != null)
-                conversion = new DistanceObjectPatternGenerator(random, original, beatmap, lastPattern, originalBeatmap);
+            {
+                var generator = new DistanceObjectPatternGenerator(Random, original, beatmap, lastPattern, originalBeatmap);
+                conversion = generator;
+
+                for (double time = original.StartTime; !Precision.DefinitelyBigger(time, generator.EndTime); time += generator.SegmentDuration)
+                {
+                    recordNote(time, positionData?.Position ?? Vector2.Zero);
+                    computeDensity(time);
+                }
+            }
             else if (endTimeData != null)
-                conversion = new EndTimeObjectPatternGenerator(random, original, beatmap, originalBeatmap);
+            {
+                conversion = new EndTimeObjectPatternGenerator(Random, original, beatmap, originalBeatmap);
+
+                recordNote(endTimeData.EndTime, new Vector2(256, 192));
+                computeDensity(endTimeData.EndTime);
+            }
             else if (positionData != null)
             {
                 computeDensity(original.StartTime);
 
-                conversion = new HitObjectPatternGenerator(random, original, beatmap, lastPattern, lastTime, lastPosition, density, lastStair, originalBeatmap);
+                conversion = new HitObjectPatternGenerator(Random, original, beatmap, lastPattern, lastTime, lastPosition, density, lastStair, originalBeatmap);
 
                 recordNote(original.StartTime, positionData.Position);
             }
 
             if (conversion == null)
-                return null;
+                yield break;
 
-            Pattern newPattern = conversion.Generate();
+            foreach (var newPattern in conversion.Generate())
+            {
+                lastPattern = conversion is EndTimeObjectPatternGenerator ? lastPattern : newPattern;
+                lastStair = (conversion as HitObjectPatternGenerator)?.StairType ?? lastStair;
 
-            lastPattern = conversion is EndTimeObjectPatternGenerator ? lastPattern : newPattern;
-            lastStair = (conversion as HitObjectPatternGenerator)?.StairType ?? lastStair;
+                foreach (var obj in newPattern.HitObjects)
+                    yield return obj;
 
-            return newPattern.HitObjects;
+            }
         }
 
         /// <summary>
@@ -171,7 +194,12 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
             {
             }
 
-            public override Pattern Generate()
+            public override IEnumerable<Pattern> Generate()
+            {
+                yield return generate();
+            }
+
+            private Pattern generate()
             {
                 var endTimeData = HitObject as IHasEndTime;
                 var positionData = HitObject as IHasXPosition;

osu.Game.Rulesets.Mania/Beatmaps/Patterns/Legacy/DistanceObjectPatternGenerator.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using osu.Framework.MathUtils;
 using osu.Game.Audio;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mania.MathUtils;
@@ -24,8 +25,9 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
         /// </summary>
         private const float osu_base_scoring_distance = 100;
 
-        private readonly double endTime;
-        private readonly double segmentDuration;
+        public readonly double EndTime;
+        public readonly double SegmentDuration;
+
         private readonly int spanCount;
 
         private PatternType convertType;
@@ -52,53 +54,81 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             // The duration of the osu! hit object
             double osuDuration = distance / osuVelocity;
 
-            endTime = hitObject.StartTime + osuDuration;
-            segmentDuration = (endTime - HitObject.StartTime) / spanCount;
+            EndTime = hitObject.StartTime + osuDuration;
+            SegmentDuration = (EndTime - HitObject.StartTime) / spanCount;
         }
 
-        public override Pattern Generate()
+        public override IEnumerable<Pattern> Generate()
+        {
+            var originalPattern = generate();
+
+            if (originalPattern.HitObjects.Count() == 1)
+            {
+                yield return originalPattern;
+                yield break;
+            }
+
+            // We need to split the intermediate pattern into two new patterns:
+            // 1. A pattern containing all objects that do not end at our EndTime.
+            // 2. A pattern containing all objects that end at our EndTime. This will be used for further pattern generation.
+            var intermediatePattern = new Pattern();
+            var endTimePattern = new Pattern();
+
+            foreach (var obj in originalPattern.HitObjects)
+            {
+                if (!Precision.AlmostEquals(EndTime, (obj as IHasEndTime)?.EndTime ?? obj.StartTime))
+                    intermediatePattern.Add(obj);
+                else
+                    endTimePattern.Add(obj);
+            }
+
+            yield return intermediatePattern;
+            yield return endTimePattern;
+        }
+
+        private Pattern generate()
         {
             if (TotalColumns == 1)
             {
                 var pattern = new Pattern();
-                addToPattern(pattern, 0, HitObject.StartTime, endTime);
+                addToPattern(pattern, 0, HitObject.StartTime, EndTime);
                 return pattern;
             }
 
             if (spanCount > 1)
             {
-                if (segmentDuration <= 90)
+                if (SegmentDuration <= 90)
                     return generateRandomHoldNotes(HitObject.StartTime, 1);
 
-                if (segmentDuration <= 120)
+                if (SegmentDuration <= 120)
                 {
                     convertType |= PatternType.ForceNotStack;
                     return generateRandomNotes(HitObject.StartTime, spanCount + 1);
                 }
 
-                if (segmentDuration <= 160)
+                if (SegmentDuration <= 160)
                     return generateStair(HitObject.StartTime);
 
-                if (segmentDuration <= 200 && ConversionDifficulty > 3)
+                if (SegmentDuration <= 200 && ConversionDifficulty > 3)
                     return generateRandomMultipleNotes(HitObject.StartTime);
 
-                double duration = endTime - HitObject.StartTime;
+                double duration = EndTime - HitObject.StartTime;
                 if (duration >= 4000)
                     return generateNRandomNotes(HitObject.StartTime, 0.23, 0, 0);
 
-                if (segmentDuration > 400 && spanCount < TotalColumns - 1 - RandomStart)
+                if (SegmentDuration > 400 && spanCount < TotalColumns - 1 - RandomStart)
                     return generateTiledHoldNotes(HitObject.StartTime);
 
                 return generateHoldAndNormalNotes(HitObject.StartTime);
             }
 
-            if (segmentDuration <= 110)
+            if (SegmentDuration <= 110)
             {
                 if (PreviousPattern.ColumnWithObjects < TotalColumns)
                     convertType |= PatternType.ForceNotStack;
                 else
                     convertType &= ~PatternType.ForceNotStack;
-                return generateRandomNotes(HitObject.StartTime, segmentDuration < 80 ? 1 : 2);
+                return generateRandomNotes(HitObject.StartTime, SegmentDuration < 80 ? 1 : 2);
             }
 
             if (ConversionDifficulty > 6.5)
@@ -148,7 +178,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             {
                 while (pattern.ColumnHasObject(nextColumn) || PreviousPattern.ColumnHasObject(nextColumn))  //find available column
                     nextColumn = Random.Next(RandomStart, TotalColumns);
-                addToPattern(pattern, nextColumn, startTime, endTime);
+                addToPattern(pattern, nextColumn, startTime, EndTime);
             }
 
             // This is can't be combined with the above loop due to RNG
@@ -156,7 +186,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             {
                 while (pattern.ColumnHasObject(nextColumn))
                     nextColumn = Random.Next(RandomStart, TotalColumns);
-                addToPattern(pattern, nextColumn, startTime, endTime);
+                addToPattern(pattern, nextColumn, startTime, EndTime);
             }
 
             return pattern;
@@ -193,7 +223,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                     nextColumn = Random.Next(RandomStart, TotalColumns);
 
                 lastColumn = nextColumn;
-                startTime += segmentDuration;
+                startTime += SegmentDuration;
             }
 
             return pattern;
@@ -223,7 +253,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             for (int i = 0; i <= spanCount; i++)
             {
                 addToPattern(pattern, column, startTime, startTime);
-                startTime += segmentDuration;
+                startTime += SegmentDuration;
 
                 // Check if we're at the borders of the stage, and invert the pattern if so
                 if (increasing)
@@ -284,7 +314,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                     addToPattern(pattern, nextColumn, startTime, startTime);
 
                 nextColumn = Random.Next(RandomStart, TotalColumns);
-                startTime += segmentDuration;
+                startTime += SegmentDuration;
             }
 
             return pattern;
@@ -372,8 +402,8 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                 while (pattern.ColumnHasObject(nextColumn))
                     nextColumn = Random.Next(RandomStart, TotalColumns);
 
-                addToPattern(pattern, nextColumn, startTime, endTime);
-                startTime += segmentDuration;
+                addToPattern(pattern, nextColumn, startTime, EndTime);
+                startTime += SegmentDuration;
             }
 
             return pattern;
@@ -402,7 +432,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             }
 
             // Create the hold note
-            addToPattern(pattern, holdColumn, startTime, endTime);
+            addToPattern(pattern, holdColumn, startTime, EndTime);
 
             int nextColumn = Random.Next(RandomStart, TotalColumns);
             int noteCount;
@@ -434,7 +464,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                 pattern.Add(rowPattern);
                 rowPattern.Clear();
 
-                startTime += segmentDuration;
+                startTime += SegmentDuration;
             }
 
             return pattern;
@@ -452,7 +482,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             if (curveData == null)
                 return HitObject.Samples;
 
-            double segmentTime = (endTime - HitObject.StartTime) / spanCount;
+            double segmentTime = (EndTime - HitObject.StartTime) / spanCount;
 
             int index = (int)(segmentTime == 0 ? 0 : (time - HitObject.StartTime) / segmentTime);
             return curveData.RepeatSamples[index];

osu.Game.Rulesets.Mania/Beatmaps/Patterns/Legacy/EndTimeObjectPatternGenerator.cs

@@ -24,7 +24,12 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             endTime = endtimeData?.EndTime ?? 0;
         }
 
-        public override Pattern Generate()
+        public override IEnumerable<Pattern> Generate()
+        {
+            yield return generate();
+        }
+
+        private Pattern generate()
         {
             var pattern = new Pattern();
 

osu.Game.Rulesets.Mania/Beatmaps/Patterns/Legacy/HitObjectPatternGenerator.cs

@@ -2,6 +2,7 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using OpenTK;
 using osu.Game.Audio;
@@ -82,127 +83,133 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             {
                 if (HitObject.Samples.Any(s => s.Name == SampleInfo.HIT_FINISH) && TotalColumns != 8)
                     convertType |= PatternType.Mirror;
-                else
+                else if (HitObject.Samples.Any(s => s.Name == SampleInfo.HIT_CLAP))
                     convertType |= PatternType.Gathered;
             }
         }
 
-        public override Pattern Generate()
+        public override IEnumerable<Pattern> Generate()
         {
-            if (TotalColumns == 1)
+            yield return generate();
+        }
+
+        private Pattern generate()
+        {
+            var pattern = new Pattern();
+
+            try
             {
-                var pattern = new Pattern();
-                addToPattern(pattern, 0);
-                return pattern;
-            }
-
-            int lastColumn = PreviousPattern.HitObjects.FirstOrDefault()?.Column ?? 0;
-
-            if ((convertType & PatternType.Reverse) > 0 && PreviousPattern.HitObjects.Any())
-            {
-                // Generate a new pattern by copying the last hit objects in reverse-column order
-                var pattern = new Pattern();
-
-                for (int i = RandomStart; i < TotalColumns; i++)
-                    if (PreviousPattern.ColumnHasObject(i))
-                        addToPattern(pattern, RandomStart + TotalColumns - i - 1);
-
-                return pattern;
-            }
-
-            if ((convertType & PatternType.Cycle) > 0 && PreviousPattern.HitObjects.Count() == 1
-                // If we convert to 7K + 1, let's not overload the special key
-                && (TotalColumns != 8 || lastColumn != 0)
-                // Make sure the last column was not the centre column
-                && (TotalColumns % 2 == 0 || lastColumn != TotalColumns / 2))
-            {
-                // Generate a new pattern by cycling backwards (similar to Reverse but for only one hit object)
-                var pattern = new Pattern();
-
-                int column = RandomStart + TotalColumns - lastColumn - 1;
-                addToPattern(pattern, column);
-
-                return pattern;
-            }
-
-            if ((convertType & PatternType.ForceStack) > 0 && PreviousPattern.HitObjects.Any())
-            {
-                // Generate a new pattern by placing on the already filled columns
-                var pattern = new Pattern();
-
-                for (int i = RandomStart; i < TotalColumns; i++)
-                    if (PreviousPattern.ColumnHasObject(i))
-                        addToPattern(pattern, i);
-
-                return pattern;
-            }
-
-            if ((convertType & PatternType.Stair) > 0 && PreviousPattern.HitObjects.Count() == 1)
-            {
-                // Generate a new pattern by placing on the next column, cycling back to the start if there is no "next"
-                var pattern = new Pattern();
-
-                int targetColumn = lastColumn + 1;
-                if (targetColumn == TotalColumns)
+                if (TotalColumns == 1)
                 {
-                    targetColumn = RandomStart;
-                    StairType = PatternType.ReverseStair;
+                    addToPattern(pattern, 0);
+                    return pattern;
                 }
 
-                addToPattern(pattern, targetColumn);
-                return pattern;
-            }
+                int lastColumn = PreviousPattern.HitObjects.FirstOrDefault()?.Column ?? 0;
 
-            if ((convertType & PatternType.ReverseStair) > 0 && PreviousPattern.HitObjects.Count() == 1)
-            {
-                // Generate a new pattern by placing on the previous column, cycling back to the end if there is no "previous"
-                var pattern = new Pattern();
-
-                int targetColumn = lastColumn - 1;
-                if (targetColumn == RandomStart - 1)
+                if ((convertType & PatternType.Reverse) > 0 && PreviousPattern.HitObjects.Any())
                 {
-                    targetColumn = TotalColumns - 1;
-                    StairType = PatternType.Stair;
+                    // Generate a new pattern by copying the last hit objects in reverse-column order
+                    for (int i = RandomStart; i < TotalColumns; i++)
+                        if (PreviousPattern.ColumnHasObject(i))
+                            addToPattern(pattern, RandomStart + TotalColumns - i - 1);
+
+                    return pattern;
                 }
 
-                addToPattern(pattern, targetColumn);
-                return pattern;
-            }
+                if ((convertType & PatternType.Cycle) > 0 && PreviousPattern.HitObjects.Count() == 1
+                                                          // If we convert to 7K + 1, let's not overload the special key
+                                                          && (TotalColumns != 8 || lastColumn != 0)
+                                                          // Make sure the last column was not the centre column
+                                                          && (TotalColumns % 2 == 0 || lastColumn != TotalColumns / 2))
+                {
+                    // Generate a new pattern by cycling backwards (similar to Reverse but for only one hit object)
+                    int column = RandomStart + TotalColumns - lastColumn - 1;
+                    addToPattern(pattern, column);
 
-            if ((convertType & PatternType.KeepSingle) > 0)
-                return generateRandomNotes(1);
+                    return pattern;
+                }
+
+                if ((convertType & PatternType.ForceStack) > 0 && PreviousPattern.HitObjects.Any())
+                {
+                    // Generate a new pattern by placing on the already filled columns
+                    for (int i = RandomStart; i < TotalColumns; i++)
+                        if (PreviousPattern.ColumnHasObject(i))
+                            addToPattern(pattern, i);
+
+                    return pattern;
+                }
+
+                if (PreviousPattern.HitObjects.Count() == 1)
+                {
+                    if ((convertType & PatternType.Stair) > 0)
+                    {
+                        // Generate a new pattern by placing on the next column, cycling back to the start if there is no "next"
+                        int targetColumn = lastColumn + 1;
+                        if (targetColumn == TotalColumns)
+                            targetColumn = RandomStart;
+
+                        addToPattern(pattern, targetColumn);
+                        return pattern;
+                    }
+
+                    if ((convertType & PatternType.ReverseStair) > 0)
+                    {
+                        // Generate a new pattern by placing on the previous column, cycling back to the end if there is no "previous"
+                        int targetColumn = lastColumn - 1;
+                        if (targetColumn == RandomStart - 1)
+                            targetColumn = TotalColumns - 1;
+
+                        addToPattern(pattern, targetColumn);
+                        return pattern;
+                    }
+                }
+
+                if ((convertType & PatternType.KeepSingle) > 0)
+                    return pattern = generateRandomNotes(1);
+
+                if ((convertType & PatternType.Mirror) > 0)
+                {
+                    if (ConversionDifficulty > 6.5)
+                        return pattern = generateRandomPatternWithMirrored(0.12, 0.38, 0.12);
+                    if (ConversionDifficulty > 4)
+                        return pattern = generateRandomPatternWithMirrored(0.12, 0.17, 0);
+                    return pattern = generateRandomPatternWithMirrored(0.12, 0, 0);
+                }
 
-            if ((convertType & PatternType.Mirror) > 0)
-            {
                 if (ConversionDifficulty > 6.5)
-                    return generateRandomPatternWithMirrored(0.12, 0.38, 0.12);
+                {
+                    if ((convertType & PatternType.LowProbability) > 0)
+                        return pattern = generateRandomPattern(0.78, 0.42, 0, 0);
+                    return pattern = generateRandomPattern(1, 0.62, 0, 0);
+                }
+
                 if (ConversionDifficulty > 4)
-                    return generateRandomPatternWithMirrored(0.12, 0.17, 0);
-                return generateRandomPatternWithMirrored(0.12, 0, 0);
-            }
+                {
+                    if ((convertType & PatternType.LowProbability) > 0)
+                        return pattern = generateRandomPattern(0.35, 0.08, 0, 0);
+                    return pattern = generateRandomPattern(0.52, 0.15, 0, 0);
+                }
 
-            if (ConversionDifficulty > 6.5)
+                if (ConversionDifficulty > 2)
+                {
+                    if ((convertType & PatternType.LowProbability) > 0)
+                        return pattern = generateRandomPattern(0.18, 0, 0, 0);
+                    return pattern = generateRandomPattern(0.45, 0, 0, 0);
+                }
+
+                return pattern = generateRandomPattern(0, 0, 0, 0);
+            }
+            finally
             {
-                if ((convertType & PatternType.LowProbability) > 0)
-                    return generateRandomPattern(0.78, 0.42, 0, 0);
-                return generateRandomPattern(1, 0.62, 0, 0);
+                foreach (var obj in pattern.HitObjects)
+                {
+                    if ((convertType & PatternType.Stair) > 0 && obj.Column == TotalColumns - 1)
+                        StairType = PatternType.ReverseStair;
+                    if ((convertType & PatternType.ReverseStair) > 0 && obj.Column == RandomStart)
+                        StairType = PatternType.Stair;
+                }
             }
-
-            if (ConversionDifficulty > 4)
-            {
-                if ((convertType & PatternType.LowProbability) > 0)
-                    return generateRandomPattern(0.35, 0.08, 0, 0);
-                return generateRandomPattern(0.52, 0.15, 0, 0);
-            }
-
-            if (ConversionDifficulty > 2)
-            {
-                if ((convertType & PatternType.LowProbability) > 0)
-                    return generateRandomPattern(0.18, 0, 0, 0);
-                return generateRandomPattern(0.45, 0, 0, 0);
-            }
-
-            return generateRandomPattern(0, 0, 0, 0);
         }
 
         /// <summary>

osu.Game.Rulesets.Mania/Beatmaps/Patterns/Legacy/PatternGenerator.cs

@@ -103,17 +103,14 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                 HitObject lastObject = OriginalBeatmap.HitObjects.LastOrDefault();
                 HitObject firstObject = OriginalBeatmap.HitObjects.FirstOrDefault();
 
-                double drainTime = (lastObject?.StartTime ?? 0) - (firstObject?.StartTime ?? 0);
-                drainTime -= OriginalBeatmap.TotalBreakTime;
+                // Drain time in seconds
+                int drainTime = (int)(((lastObject?.StartTime ?? 0) - (firstObject?.StartTime ?? 0) - OriginalBeatmap.TotalBreakTime) / 1000);
 
                 if (drainTime == 0)
-                    drainTime = 10000000;
-
-                // We need this in seconds
-                drainTime /= 1000;
+                    drainTime = 10000;
 
                 BeatmapDifficulty difficulty = OriginalBeatmap.BeatmapInfo.BaseDifficulty;
-                conversionDifficulty = ((difficulty.DrainRate + MathHelper.Clamp(difficulty.ApproachRate, 4, 7)) / 1.5 + OriginalBeatmap.HitObjects.Count() / drainTime * 9f) / 38f * 5f / 1.15;
+                conversionDifficulty = ((difficulty.DrainRate + MathHelper.Clamp(difficulty.ApproachRate, 4, 7)) / 1.5 + (double)OriginalBeatmap.HitObjects.Count() / drainTime * 9f) / 38f * 5f / 1.15;
                 conversionDifficulty = Math.Min(conversionDifficulty.Value, 12);
 
                 return conversionDifficulty.Value;

osu.Game.Rulesets.Mania/Beatmaps/Patterns/PatternGenerator.cs

@@ -2,6 +2,7 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using System;
+using System.Collections.Generic;
 using osu.Game.Rulesets.Objects;
 
 namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns
@@ -42,9 +43,9 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns
         }
 
         /// <summary>
-        /// Generates the pattern for <see cref="HitObject"/>, filled with hit objects.
+        /// Generates the patterns for <see cref="HitObject"/>, each filled with hit objects.
         /// </summary>
-        /// <returns>The <see cref="Pattern"/> containing the hit objects.</returns>
-        public abstract Pattern Generate();
+        /// <returns>The <see cref="Pattern"/>s containing the hit objects.</returns>
+        public abstract IEnumerable<Pattern> Generate();
     }
 }

osu.Game.Rulesets.Mania/MathUtils/FastRandom.cs

@@ -15,11 +15,15 @@ namespace osu.Game.Rulesets.Mania.MathUtils
         private const uint y = 842502087;
         private const uint z = 3579807591;
         private const uint w = 273326509;
-        private uint _x, _y = y, _z = z, _w = w;
+
+        internal uint X { get; private set; }
+        internal uint Y { get; private set; } = y;
+        internal uint Z { get; private set; } = z;
+        internal uint W { get; private set; } = w;
 
         public FastRandom(int seed)
         {
-            _x = (uint)seed;
+            X = (uint)seed;
         }
 
         public FastRandom()
@@ -33,11 +37,11 @@ namespace osu.Game.Rulesets.Mania.MathUtils
         /// <returns>The random value.</returns>
         public uint NextUInt()
         {
-            uint t = _x ^ _x << 11;
-            _x = _y;
-            _y = _z;
-            _z = _w;
-            return _w = _w ^ _w >> 19 ^ t ^ t >> 8;
+            uint t = X ^ X << 11;
+            X = Y;
+            Y = Z;
+            Z = W;
+            return W = W ^ W >> 19 ^ t ^ t >> 8;
         }
 
         /// <summary>

osu.Game.Rulesets.Mania/Resources/Testing/Beatmaps/basic-expected-conversion.json

@@ -1,103 +1,132 @@
 {
     "Mappings": [{
-            "StartTime": 500,
-            "Objects": [{
-                    "StartTime": 500,
-                    "EndTime": 2500,
-                    "Column": 0
-                },
-                {
-                    "StartTime": 1500,
-                    "EndTime": 2500,
-                    "Column": 1
-                }
-            ]
-        },
-        {
-            "StartTime": 3000,
-            "Objects": [{
-                "StartTime": 3000,
-                "EndTime": 4000,
-                "Column": 2
-            }]
-        },
-        {
-            "StartTime": 4500,
-            "Objects": [{
-                "StartTime": 4500,
-                "EndTime": 5500,
-                "Column": 4
-            }]
-        },
-        {
-            "StartTime": 6000,
-            "Objects": [{
-                "StartTime": 6000,
-                "EndTime": 6500,
-                "Column": 2
-            }]
-        },
-        {
-            "StartTime": 7000,
-            "Objects": [{
-                "StartTime": 7000,
-                "EndTime": 8000,
-                "Column": 2
-            }]
-        },
-        {
-            "StartTime": 8500,
-            "Objects": [{
-                "StartTime": 8500,
-                "EndTime": 11000,
-                "Column": 0
-            }]
-        },
-        {
-            "StartTime": 11500,
-            "Objects": [{
-                "StartTime": 11500,
-                "EndTime": 12000,
-                "Column": 1
-            }]
-        },
-        {
-            "StartTime": 12500,
-            "Objects": [{
-                "StartTime": 12500,
-                "EndTime": 16500,
-                "Column": 4
-            }]
-        },
-        {
-            "StartTime": 17000,
-            "Objects": [{
-                "StartTime": 17000,
-                "EndTime": 18000,
-                "Column": 2
-            }]
-        },
-        {
-            "StartTime": 18500,
-            "Objects": [{
-                "StartTime": 18500,
-                "EndTime": 19450,
-                "Column": 0
-            }]
-        },
-        {
-            "StartTime": 19875,
-            "Objects": [{
-                    "StartTime": 19875,
-                    "EndTime": 23875,
-                    "Column": 1
-                },
-                {
-                    "StartTime": 19875,
-                    "EndTime": 23875,
-                    "Column": 0
-                }
-            ]
-        }
-    ]
+        "RandomW": 2659373485,
+        "RandomX": 3579807591,
+        "RandomY": 273326509,
+        "RandomZ": 272969173,
+        "StartTime": 500.0,
+        "Objects": [{
+            "StartTime": 500.0,
+            "EndTime": 2500.0,
+            "Column": 0
+        }, {
+            "StartTime": 1500.0,
+            "EndTime": 2500.0,
+            "Column": 1
+        }]
+    }, {
+        "RandomW": 3083803045,
+        "RandomX": 273326509,
+        "RandomY": 272969173,
+        "RandomZ": 2659373485,
+        "StartTime": 3000.0,
+        "Objects": [{
+            "StartTime": 3000.0,
+            "EndTime": 4000.0,
+            "Column": 2
+        }]
+    }, {
+        "RandomW": 4073554232,
+        "RandomX": 272969173,
+        "RandomY": 2659373485,
+        "RandomZ": 3083803045,
+        "StartTime": 4500.0,
+        "Objects": [{
+            "StartTime": 4500.0,
+            "EndTime": 5500.0,
+            "Column": 4
+        }]
+    }, {
+        "RandomW": 3420401969,
+        "RandomX": 2659373485,
+        "RandomY": 3083803045,
+        "RandomZ": 4073554232,
+        "StartTime": 6000.0,
+        "Objects": [{
+            "StartTime": 6000.0,
+            "EndTime": 6500.0,
+            "Column": 2
+        }]
+    }, {
+        "RandomW": 1129881182,
+        "RandomX": 3083803045,
+        "RandomY": 4073554232,
+        "RandomZ": 3420401969,
+        "StartTime": 7000.0,
+        "Objects": [{
+            "StartTime": 7000.0,
+            "EndTime": 8000.0,
+            "Column": 2
+        }]
+    }, {
+        "RandomW": 315568458,
+        "RandomX": 3420401969,
+        "RandomY": 1129881182,
+        "RandomZ": 2358617505,
+        "StartTime": 8500.0,
+        "Objects": [{
+            "StartTime": 8500.0,
+            "EndTime": 11000.0,
+            "Column": 0
+        }]
+    }, {
+        "RandomW": 548134043,
+        "RandomX": 1129881182,
+        "RandomY": 2358617505,
+        "RandomZ": 315568458,
+        "StartTime": 11500.0,
+        "Objects": [{
+            "StartTime": 11500.0,
+            "EndTime": 12000.0,
+            "Column": 1
+        }]
+    }, {
+        "RandomW": 3979422122,
+        "RandomX": 548134043,
+        "RandomY": 2810584254,
+        "RandomZ": 2250186050,
+        "StartTime": 12500.0,
+        "Objects": [{
+            "StartTime": 12500.0,
+            "EndTime": 16500.0,
+            "Column": 4
+        }]
+    }, {
+        "RandomW": 2466283411,
+        "RandomX": 2810584254,
+        "RandomY": 2250186050,
+        "RandomZ": 3979422122,
+        "StartTime": 17000.0,
+        "Objects": [{
+            "StartTime": 17000.0,
+            "EndTime": 18000.0,
+            "Column": 2
+        }]
+    }, {
+        "RandomW": 83157665,
+        "RandomX": 2250186050,
+        "RandomY": 3979422122,
+        "RandomZ": 2466283411,
+        "StartTime": 18500.0,
+        "Objects": [{
+            "StartTime": 18500.0,
+            "EndTime": 19450.0,
+            "Column": 0
+        }]
+    }, {
+        "RandomW": 2383087700,
+        "RandomX": 83157665,
+        "RandomY": 2055150192,
+        "RandomZ": 510071020,
+        "StartTime": 19875.0,
+        "Objects": [{
+            "StartTime": 19875.0,
+            "EndTime": 23875.0,
+            "Column": 1
+        }, {
+            "StartTime": 19875.0,
+            "EndTime": 23875.0,
+            "Column": 0
+        }]
+    }]
 }

osu.Game/Tests/Beatmaps/BeatmapConversionTest.cs

@@ -25,6 +25,8 @@ namespace osu.Game.Tests.Beatmaps
 
         protected abstract string ResourceAssembly { get; }
 
+        protected IBeatmapConverter Converter { get; private set; }
+
         protected void Test(string name)
         {
             var ourResult = convert(name);
@@ -41,14 +43,22 @@ namespace osu.Game.Tests.Beatmaps
                         Assert.Fail($"A conversion did not generate any hitobjects, but should have, for hitobject at time: {expectedResult.Mappings[mappingCounter].StartTime}\n");
                     else if (mappingCounter >= expectedResult.Mappings.Count)
                         Assert.Fail($"A conversion generated hitobjects, but should not have, for hitobject at time: {ourResult.Mappings[mappingCounter].StartTime}\n");
+                    else if (!expectedResult.Mappings[mappingCounter].Equals(ourResult.Mappings[mappingCounter]))
+                    {
+                        var expectedMapping = expectedResult.Mappings[mappingCounter];
+                        var ourMapping = ourResult.Mappings[mappingCounter];
+
+                        Assert.Fail($"The conversion mapping differed for object at time {expectedMapping.StartTime}:\n"
+                                    + $"Expected {JsonConvert.SerializeObject(expectedMapping)}\n"
+                                    + $"Received: {JsonConvert.SerializeObject(ourMapping)}\n");
+                    }
                     else
                     {
-                        var counter = mappingCounter;
+                        var ourMapping = ourResult.Mappings[mappingCounter];
+                        var expectedMapping = expectedResult.Mappings[mappingCounter];
+
                         Assert.Multiple(() =>
                         {
-                            var ourMapping = ourResult.Mappings[counter];
-                            var expectedMapping = expectedResult.Mappings[counter];
-
                             int objectCounter = 0;
                             while (true)
                             {
@@ -60,10 +70,6 @@ namespace osu.Game.Tests.Beatmaps
                                 else if (objectCounter >= expectedMapping.Objects.Count)
                                     Assert.Fail($"The conversion generated a hitobject, but should not have, for hitobject at time: {ourMapping.StartTime}:\n"
                                                 + $"Received: {JsonConvert.SerializeObject(ourMapping.Objects[objectCounter])}\n");
-                                else if (!expectedMapping.Equals(ourMapping))
-                                    Assert.Fail($"The conversion mapping differed for object at time {expectedMapping.StartTime}:\n"
-                                                + $"Expected {JsonConvert.SerializeObject(expectedMapping)}\n"
-                                                + $"Received: {JsonConvert.SerializeObject(ourMapping)}\n");
                                 else if (!expectedMapping.Objects[objectCounter].Equals(ourMapping.Objects[objectCounter]))
                                 {
                                     Assert.Fail($"The conversion generated differing hitobjects for object at time: {expectedMapping.StartTime}:\n"
@@ -88,10 +94,11 @@ namespace osu.Game.Tests.Beatmaps
             var rulesetInstance = CreateRuleset();
             beatmap.BeatmapInfo.Ruleset = beatmap.BeatmapInfo.RulesetID == rulesetInstance.RulesetInfo.ID ? rulesetInstance.RulesetInfo : new RulesetInfo();
 
-            var result = new ConvertResult();
-            var converter = rulesetInstance.CreateBeatmapConverter(beatmap);
+            Converter = rulesetInstance.CreateBeatmapConverter(beatmap);
 
-            converter.ObjectConverted += (orig, converted) =>
+            var result = new ConvertResult();
+
+            Converter.ObjectConverted += (orig, converted) =>
             {
                 converted.ForEach(h => h.ApplyDefaults(beatmap.ControlPointInfo, beatmap.BeatmapInfo.BaseDifficulty));
 
@@ -103,7 +110,7 @@ namespace osu.Game.Tests.Beatmaps
                 result.Mappings.Add(mapping);
             };
 
-            IBeatmap convertedBeatmap = converter.Convert();
+            IBeatmap convertedBeatmap = Converter.Convert();
             rulesetInstance.CreateBeatmapProcessor(convertedBeatmap)?.PostProcess();
 
             return result;