osu/osu.Game/Beatmaps/BeatmapConverter.cs

109 lines
4.3 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;
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;
}
/// <summary>
/// Checks if a Beatmap can be converted using this Beatmap Converter.
/// </summary>
/// <param name="beatmap">The Beatmap to check.</param>
/// <returns>Whether the Beatmap can be converted using this Beatmap Converter.</returns>
public bool CanConvert(Beatmap beatmap) => ValidConversionTypes.All(t => beatmap.HitObjects.Any(t.IsInstanceOfType));
/// <summary>
/// Converts a Beatmap using this Beatmap Converter.
/// </summary>
/// <param name="original">The un-converted Beatmap.</param>
/// <returns>The converted Beatmap.</returns>
public Beatmap<T> Convert(Beatmap original)
{
// We always operate on a clone of the original beatmap, to not modify it game-wide
return ConvertBeatmap(new Beatmap(original));
}
void IBeatmapConverter.Convert(Beatmap original) => Convert(original);
/// <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(Beatmap original)
{
var beatmap = CreateBeatmap();
beatmap.BeatmapInfo = original.BeatmapInfo;
beatmap.ControlPointInfo = original.ControlPointInfo;
beatmap.HitObjects = original.HitObjects.SelectMany(h => convert(h, original)).ToList();
return beatmap;
}
/// <summary>
/// Converts a hit object.
/// </summary>
/// <param name="original">The hit object to convert.</param>
/// <param name="beatmap">The un-converted Beatmap.</param>
/// <returns>The converted hit object.</returns>
private IEnumerable<T> convert(HitObject original, Beatmap beatmap)
{
// Check if the hitobject is already the converted type
T tObject = original as T;
if (tObject != null)
{
yield return tObject;
yield break;
}
var converted = ConvertHitObject(original, beatmap).ToList();
ObjectConverted?.Invoke(original, converted);
// Convert the hit object
foreach (var obj in converted)
{
if (obj == null)
continue;
yield return obj;
}
}
/// <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, Beatmap beatmap);
}
}