osu/osu.Game/Storyboards/Commands/StoryboardLoopingGroup.cs

67 lines
2.9 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 osu.Framework.Graphics.Transforms;
namespace osu.Game.Storyboards.Commands
{
public class StoryboardLoopingGroup : StoryboardCommandGroup
{
private readonly double loopStartTime;
/// <summary>
/// The total number of times this loop is played back. Always greater than zero.
/// </summary>
public readonly int TotalIterations;
/// <summary>
/// Construct a new command loop.
/// </summary>
/// <param name="startTime">The start time of the loop.</param>
/// <param name="repeatCount">The number of times the loop should repeat. Should be greater than zero. Zero means a single playback.</param>
public StoryboardLoopingGroup(double startTime, int repeatCount)
{
ArgumentOutOfRangeException.ThrowIfNegative(repeatCount);
loopStartTime = startTime;
TotalIterations = repeatCount + 1;
}
protected override void AddCommand<T>(ICollection<StoryboardCommand<T>> list, StoryboardCommand<T> command)
=> base.AddCommand(list, new StoryboardLoopingCommand<T>(command, this));
public override string ToString() => $"{loopStartTime} x{TotalIterations}";
private class StoryboardLoopingCommand<T> : StoryboardCommand<T>
{
private readonly StoryboardCommand<T> command;
private readonly StoryboardLoopingGroup loopingGroup;
public StoryboardLoopingCommand(StoryboardCommand<T> command, StoryboardLoopingGroup loopingGroup)
// In an ideal world, we would multiply the command duration by TotalIterations in command end time.
// Unfortunately this would clash with how stable handled end times, and results in some storyboards playing outro
// sequences for minutes or hours.
: base(command.Easing, loopingGroup.loopStartTime + command.StartTime, loopingGroup.loopStartTime + command.EndTime, command.StartValue, command.EndValue)
{
this.command = command;
this.loopingGroup = loopingGroup;
}
public override string PropertyName => command.PropertyName;
public override void ApplyInitialValue<TDrawable>(TDrawable d) => command.ApplyInitialValue(d);
public override TransformSequence<TDrawable> ApplyTransforms<TDrawable>(TDrawable d)
{
if (loopingGroup.TotalIterations == 0)
return command.ApplyTransforms(d);
double loopingGroupDuration = loopingGroup.Duration;
return command.ApplyTransforms(d).Loop(loopingGroupDuration - Duration, loopingGroup.TotalIterations);
}
}
}
}