osu/osu.Game/Beatmaps/BeatmapDifficulty.cs

70 lines
3.3 KiB
C#

// 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.ComponentModel.DataAnnotations.Schema;
using Newtonsoft.Json;
namespace osu.Game.Beatmaps
{
public class BeatmapDifficulty
{
/// <summary>
/// The default value used for all difficulty settings except <see cref="SliderMultiplier"/> and <see cref="SliderTickRate"/>.
/// </summary>
public const float DEFAULT_DIFFICULTY = 5;
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
[JsonIgnore]
public int ID { get; set; }
public float DrainRate { get; set; } = DEFAULT_DIFFICULTY;
public float CircleSize { get; set; } = DEFAULT_DIFFICULTY;
public float OverallDifficulty { get; set; } = DEFAULT_DIFFICULTY;
private float? approachRate;
public float ApproachRate
{
get => approachRate ?? OverallDifficulty;
set => approachRate = value;
}
public double SliderMultiplier { get; set; } = 1;
public double SliderTickRate { get; set; } = 1;
/// <summary>
/// Returns a shallow-clone of this <see cref="BeatmapDifficulty"/>.
/// </summary>
public BeatmapDifficulty Clone() => (BeatmapDifficulty)MemberwiseClone();
/// <summary>
/// Maps a difficulty value [0, 10] to a two-piece linear range of values.
/// </summary>
/// <param name="difficulty">The difficulty value to be mapped.</param>
/// <param name="min">Minimum of the resulting range which will be achieved by a difficulty value of 0.</param>
/// <param name="mid">Midpoint of the resulting range which will be achieved by a difficulty value of 5.</param>
/// <param name="max">Maximum of the resulting range which will be achieved by a difficulty value of 10.</param>
/// <returns>Value to which the difficulty value maps in the specified range.</returns>
public static double DifficultyRange(double difficulty, double min, double mid, double max)
{
if (difficulty > 5)
return mid + (max - mid) * (difficulty - 5) / 5;
if (difficulty < 5)
return mid - (mid - min) * (5 - difficulty) / 5;
return mid;
}
/// <summary>
/// Maps a difficulty value [0, 10] to a two-piece linear range of values.
/// </summary>
/// <param name="difficulty">The difficulty value to be mapped.</param>
/// <param name="range">The values that define the two linear ranges.</param>
/// <param name="range.od0">Minimum of the resulting range which will be achieved by a difficulty value of 0.</param>
/// <param name="range.od5">Midpoint of the resulting range which will be achieved by a difficulty value of 5.</param>
/// <param name="range.od10">Maximum of the resulting range which will be achieved by a difficulty value of 10.</param>
/// <returns>Value to which the difficulty value maps in the specified range.</returns>
public static double DifficultyRange(double difficulty, (double od0, double od5, double od10) range)
=> DifficultyRange(difficulty, range.od0, range.od5, range.od10);
}
}