osukey/osu.Game.Rulesets.Osu/Difficulty/Skills/Aim.cs

// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE

using System;
using osu.Game.Rulesets.Osu.Difficulty.Preprocessing;

namespace osu.Game.Rulesets.Osu.Difficulty.Skills
{
    /// <summary>
    /// Represents the skill required to correctly aim at every object in the map with a uniform CircleSize and normalized distances.
    /// </summary>
    public class Aim : Skill
    {
        protected override double SkillMultiplier => 26.25;
        protected override double StrainDecayBase => 0.15;

        protected override double StrainValueOf(OsuDifficultyHitObject current)
        {
            double angleBonus = 1.0;

            if (current.Angle != null)
            {
                double angle = current.Angle.Value * 180 / Math.PI;

                if (current.JumpDistance > SINGLE_SPACING_THRESHOLD)
                {
                    if (angle > 75)
                        angleBonus = (angle / 45 - 75) / 2;
                    else if (angle > 120)
                        angleBonus = 0.5;
                }
            }

            return angleBonus * (
                       Math.Pow(current.JumpDistance - SINGLE_SPACING_THRESHOLD, 0.99)
                       + Math.Pow(current.TravelDistance, 0.99)
                       + Math.Pow(current.JumpDistance, 0.99)
                   ) / current.StrainTime;
        }
    }
}