osu/osu.Game.Rulesets.Osu/Mods/OsuModRandom.cs

64 lines
2.2 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 enable
using System;
using System.Linq;
using osu.Framework.Utils;
using osu.Game.Beatmaps;
using osu.Game.Rulesets.Mods;
using osu.Game.Rulesets.Objects;
using osu.Game.Rulesets.Osu.Beatmaps;
using osu.Game.Rulesets.Osu.UI;
using osu.Game.Rulesets.Osu.Utils;
namespace osu.Game.Rulesets.Osu.Mods
{
/// <summary>
/// Mod that randomises the positions of the <see cref="HitObject"/>s
/// </summary>
public class OsuModRandom : ModRandom, IApplicableToBeatmap
{
public override string Description => "It never gets boring!";
private static readonly float playfield_diagonal = OsuPlayfield.BASE_SIZE.LengthFast;
private Random? rng;
public void ApplyToBeatmap(IBeatmap beatmap)
{
if (!(beatmap is OsuBeatmap osuBeatmap))
return;
Seed.Value ??= RNG.Next();
rng = new Random((int)Seed.Value);
var positionInfos = OsuHitObjectGenerationUtils.GeneratePositionInfos(osuBeatmap.HitObjects);
float rateOfChangeMultiplier = 0;
foreach (var positionInfo in positionInfos)
{
// rateOfChangeMultiplier only changes every 5 iterations in a combo
// to prevent shaky-line-shaped streams
if (positionInfo.HitObject.IndexInCurrentCombo % 5 == 0)
rateOfChangeMultiplier = (float)rng.NextDouble() * 2 - 1;
if (positionInfo == positionInfos.First())
{
positionInfo.DistanceFromPrevious = (float)(rng.NextDouble() * OsuPlayfield.BASE_SIZE.X / 2);
positionInfo.RelativeAngle = (float)(rng.NextDouble() * 2 * Math.PI - Math.PI);
}
else
{
positionInfo.RelativeAngle = rateOfChangeMultiplier * 2 * (float)Math.PI * Math.Min(1f, positionInfo.DistanceFromPrevious / (playfield_diagonal * 0.5f));
}
}
osuBeatmap.HitObjects = OsuHitObjectGenerationUtils.RepositionHitObjects(positionInfos);
}
}
}