osu/osu.Game/Beatmaps/BeatmapConverter.cs

115 lines
3.9 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.
using System;
using System.Collections.Generic;
using System.Linq;
using osu.Game.Rulesets.Objects;
namespace osu.Game.Beatmaps
{
/// <summary>
/// Converts a Beatmap for another mode.
/// </summary>
/// <typeparam name="T">The type of HitObject stored in the Beatmap.</typeparam>
public abstract class BeatmapConverter<T> : IBeatmapConverter
where T : HitObject
{
private event Action<HitObject, IEnumerable<HitObject>> ObjectConverted;
event Action<HitObject, IEnumerable<HitObject>> IBeatmapConverter.ObjectConverted
{
add => ObjectConverted += value;
remove => ObjectConverted -= value;
}
public IBeatmap Beatmap { get; }
protected BeatmapConverter(IBeatmap beatmap)
{
Beatmap = beatmap;
}
/// <summary>
/// Whether <see cref="Beatmap"/> can be converted by this <see cref="BeatmapConverter{T}"/>.
/// </summary>
public bool CanConvert => !Beatmap.HitObjects.Any() || ValidConversionTypes.All(t => Beatmap.HitObjects.Any(t.IsInstanceOfType));
/// <summary>
/// Converts <see cref="Beatmap"/>.
/// </summary>
/// <returns>The converted Beatmap.</returns>
public IBeatmap Convert()
{
// We always operate on a clone of the original beatmap, to not modify it game-wide
return ConvertBeatmap(Beatmap.Clone());
}
/// <summary>
/// Performs the conversion of a Beatmap using this Beatmap Converter.
/// </summary>
/// <param name="original">The un-converted Beatmap.</param>
/// <returns>The converted Beatmap.</returns>
protected virtual Beatmap<T> ConvertBeatmap(IBeatmap original)
{
var beatmap = CreateBeatmap();
beatmap.BeatmapInfo = original.BeatmapInfo;
beatmap.ControlPointInfo = original.ControlPointInfo;
beatmap.HitObjects = convertHitObjects(original.HitObjects, original);
beatmap.Breaks = original.Breaks;
return beatmap;
}
private List<T> convertHitObjects(IReadOnlyList<HitObject> hitObjects, IBeatmap beatmap)
{
var result = new List<T>(hitObjects.Count);
foreach (var obj in hitObjects)
{
if (obj is T tObj)
{
result.Add(tObj);
continue;
}
var converted = ConvertHitObject(obj, beatmap);
if (ObjectConverted != null)
{
converted = converted.ToList();
ObjectConverted.Invoke(obj, converted);
}
foreach (var c in converted)
{
if (c != null)
result.Add(c);
}
}
return result;
}
/// <summary>
/// The types of HitObjects that can be converted to be used for this Beatmap.
/// </summary>
protected abstract IEnumerable<Type> ValidConversionTypes { get; }
/// <summary>
/// Creates the <see cref="Beatmap{T}"/> that will be returned by this <see cref="BeatmapProcessor{T}"/>.
/// </summary>
protected virtual Beatmap<T> CreateBeatmap() => new Beatmap<T>();
/// <summary>
/// Performs the conversion of a hit object.
/// This method is generally executed sequentially for all objects in a beatmap.
/// </summary>
/// <param name="original">The hit object to convert.</param>
/// <param name="beatmap">The un-converted Beatmap.</param>
/// <returns>The converted hit object.</returns>
protected abstract IEnumerable<T> ConvertHitObject(HitObject original, IBeatmap beatmap);
}
}