Add snap/flow perf attributes

Author: Givikap120

osu.Game.Rulesets.Osu/Difficulty/OsuPerformanceAttributes.cs

@@ -42,6 +42,12 @@ public class OsuPerformanceAttributes : PerformanceAttributes
         [JsonProperty("speed_estimated_slider_breaks")]
         public double SpeedEstimatedSliderBreaks { get; set; }
 
+        [JsonProperty("snap")]
+        public double Snap { get; set; }
+
+        [JsonProperty("flow")]
+        public double Flow { get; set; }
+
         public override IEnumerable<PerformanceDisplayAttribute> GetAttributesForDisplay()
         {
             foreach (var attribute in base.GetAttributesForDisplay())

osu.Game.Rulesets.Osu/Difficulty/OsuPerformanceCalculator.cs

@@ -165,6 +165,8 @@ protected override PerformanceAttributes CreatePerformanceAttributes(ScoreInfo s
                 AimEstimatedSliderBreaks = aimEstimatedSliderBreaks,
                 SpeedEstimatedSliderBreaks = speedEstimatedSliderBreaks,
                 SpeedDeviation = speedDeviation,
+                Snap = aimValue * Math.Pow(osuAttributes.SnapAimDifficulty / Math.Max(osuAttributes.AimDifficulty, 0.01), 3),
+                Flow = aimValue * Math.Pow(osuAttributes.FlowAimDifficulty / Math.Max(osuAttributes.AimDifficulty, 0.01), 3),
                 Total = totalValue
             };
         }