osu/osu.Game/Beatmaps/StarDifficulty.cs

85 lines
3.2 KiB
C#

// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
// See the LICENCE file in the repository root for full licence text.
#nullable disable
using JetBrains.Annotations;
using osu.Framework.Utils;
using osu.Game.Rulesets.Difficulty;
namespace osu.Game.Beatmaps
{
public readonly struct StarDifficulty
{
/// <summary>
/// The star difficulty rating for the given beatmap.
/// </summary>
public readonly double Stars;
/// <summary>
/// The maximum combo achievable on the given beatmap.
/// </summary>
public readonly int MaxCombo;
/// <summary>
/// The difficulty attributes computed for the given beatmap.
/// Might not be available if the star difficulty is associated with a beatmap that's not locally available.
/// </summary>
[CanBeNull]
public readonly DifficultyAttributes Attributes;
/// <summary>
/// Creates a <see cref="StarDifficulty"/> structure based on <see cref="DifficultyAttributes"/> computed
/// by a <see cref="DifficultyCalculator"/>.
/// </summary>
public StarDifficulty([NotNull] DifficultyAttributes attributes)
{
Stars = double.IsFinite(attributes.StarRating) ? attributes.StarRating : 0;
MaxCombo = attributes.MaxCombo;
Attributes = attributes;
// Todo: Add more members (BeatmapInfo.DifficultyRating? Attributes? Etc...)
}
/// <summary>
/// Creates a <see cref="StarDifficulty"/> structure with a pre-populated star difficulty and max combo
/// in scenarios where computing <see cref="DifficultyAttributes"/> is not feasible (i.e. when working with online sources).
/// </summary>
public StarDifficulty(double starDifficulty, int maxCombo)
{
Stars = double.IsFinite(starDifficulty) ? starDifficulty : 0;
MaxCombo = maxCombo;
Attributes = null;
}
public DifficultyRating DifficultyRating => GetDifficultyRating(Stars);
/// <summary>
/// Retrieves the <see cref="DifficultyRating"/> that describes a star rating.
/// </summary>
/// <remarks>
/// For more information, see: https://osu.ppy.sh/help/wiki/Difficulties
/// </remarks>
/// <param name="starRating">The star rating.</param>
/// <returns>The <see cref="DifficultyRating"/> that best describes <paramref name="starRating"/>.</returns>
public static DifficultyRating GetDifficultyRating(double starRating)
{
if (Precision.AlmostBigger(starRating, 6.5, 0.005))
return DifficultyRating.ExpertPlus;
if (Precision.AlmostBigger(starRating, 5.3, 0.005))
return DifficultyRating.Expert;
if (Precision.AlmostBigger(starRating, 4.0, 0.005))
return DifficultyRating.Insane;
if (Precision.AlmostBigger(starRating, 2.7, 0.005))
return DifficultyRating.Hard;
if (Precision.AlmostBigger(starRating, 2.0, 0.005))
return DifficultyRating.Normal;
return DifficultyRating.Easy;
}
}
}