protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)
{
if (beatmap.HitObjects.Count == 0)
{
return new OsuDifficultyAttributes {
Mods = mods, Skills = skills
}
}
;
List <double> combinedBonuses = calculateCombinedBonuses(skills);
int totalHits = beatmap.HitObjects.Count(h => h is HitCircle || h is Slider);
Aim aimSkill = skills[0] as Aim;
Speed speedSkill = skills[1] as Speed;
//minor discrepancy here because the combined bonus is not taken into account for the length value
double aimTotal = aimSkill.LengthValue(totalHits) * 2;
double speedTotal = speedSkill.LengthValue(totalHits) * 2;
aimSkill.AddCombinedCorrection(combinedBonuses);
speedSkill.AddCombinedCorrection(combinedBonuses, skills[4]);
double aimDifficulty = aimSkill.CombinedDifficultyValue();
double speedDifficulty = speedSkill.CombinedDifficultyValue();
double aimRating = Math.Sqrt(aimDifficulty);
double speedRating = Math.Sqrt(speedDifficulty);
//consistency
double totalAimBonus = Math.Pow(aimSkill.ConsistencyValue(aimDifficulty), 0.7) * 0.045
+ calculateMixedAimBonus(skills[2] as SnapAim, skills[3] as FlowAim);
double totalSpeedBonus = Math.Pow(speedSkill.ConsistencyValue(speedDifficulty), 0.7) * 0.045;
//calculate the SR first to avoid unnecessary inflation, this should pose no problems as it is just a display value
double displayAim = aimRating * (1.0 + totalAimBonus) * difficulty_multiplier;
double displaySpeed = speedRating * (1.0 + totalSpeedBonus) * difficulty_multiplier;
double starRating = displayAim + displaySpeed + Math.Abs(displayAim - displaySpeed) / 2;
//length bonus
double aimDiffMultiplier = 1.0 + Math.Pow(aimRating, 1.5) / 15000;
aimTotal = Math.Pow(aimTotal, aimDiffMultiplier);
double aimLengthBonus = 1.0 + 0.36 * Math.Min(1.0, aimTotal / 2000.0) +
(aimTotal > 2000 ? Math.Log10(aimTotal / 2000.0) * 0.48 : 0.0);
double speedLengthBonus = 1.0 + 0.1 * Math.Min(1.0, speedTotal / 2000.0) +
(speedTotal > 2000 ? Math.Log10(speedTotal / 2000.0) * 0.2 : 0.0);
totalAimBonus += Math.Pow(aimLengthBonus, 0.33);
totalSpeedBonus += Math.Pow(speedLengthBonus, 0.33);
aimRating *= totalAimBonus * difficulty_multiplier;
speedRating *= totalSpeedBonus * difficulty_multiplier;
HitWindows hitWindows = new OsuHitWindows();
hitWindows.SetDifficulty(beatmap.BeatmapInfo.BaseDifficulty.OverallDifficulty);
// Todo: These int casts are temporary to achieve 1:1 results with osu!stable, and should be removed in the future
double hitWindowGreat = (int)(hitWindows.WindowFor(HitResult.Great)) / clockRate;
double preempt = (int)BeatmapDifficulty.DifficultyRange(beatmap.BeatmapInfo.BaseDifficulty.ApproachRate, 1800, 1200, 450) / clockRate;
int maxCombo = beatmap.HitObjects.Count;
// Add the ticks + tail of the slider. 1 is subtracted because the head circle would be counted twice (once for the slider itself in the line above)
maxCombo += beatmap.HitObjects.OfType <Slider>().Sum(s => s.NestedHitObjects.Count - 1);
int hitCirclesCount = beatmap.HitObjects.Count(h => h is HitCircle);
int spinnerCount = beatmap.HitObjects.Count(h => h is Spinner);
return(new OsuDifficultyAttributes
{
StarRating = starRating,
Mods = mods,
AimStrain = aimRating,
SpeedStrain = speedRating,
ApproachRate = preempt > 1200 ? (1800 - preempt) / 120 : (1200 - preempt) / 150 + 5,
OverallDifficulty = (80 - hitWindowGreat) / 6,
MaxCombo = maxCombo,
HitCircleCount = hitCirclesCount,
SpinnerCount = spinnerCount,
Skills = skills
});
}
