osu/osu.Game/Rulesets/Replays/FramedReplayInputHandler.cs

194 lines
7.4 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.Collections.Generic;
using System.Linq;
using osu.Framework.Input.StateChanges;
using osu.Game.Input.Handlers;
using osu.Game.Replays;
namespace osu.Game.Rulesets.Replays
{
/// <summary>
/// The ReplayHandler will take a replay and handle the propagation of updates to the input stack.
/// It handles logic of any frames which *must* be executed.
/// </summary>
public abstract class FramedReplayInputHandler<TFrame> : ReplayInputHandler
where TFrame : ReplayFrame
{
/// <summary>
/// Whether we have at least one replay frame.
/// </summary>
public bool HasFrames => Frames.Count != 0;
/// <summary>
/// Whether we are waiting for new frames to be received.
/// </summary>
public bool WaitingForFrame => !replay.HasReceivedAllFrames && currentFrameIndex == Frames.Count - 1;
/// <summary>
/// The current frame of the replay.
/// The current time is always between the start and the end time of the current frame.
/// </summary>
/// <remarks>Returns null if the current time is strictly before the first frame.</remarks>
public TFrame? CurrentFrame => currentFrameIndex == -1 ? null : (TFrame)Frames[currentFrameIndex];
/// <summary>
/// The next frame of the replay.
/// The start time of <see cref="NextFrame"/> is always greater or equal to the start time of <see cref="CurrentFrame"/> regardless of the seeking direction.
/// </summary>
/// <remarks>Returns null if the current frame is the last frame.</remarks>
public TFrame? NextFrame => currentFrameIndex == Frames.Count - 1 ? null : (TFrame)Frames[currentFrameIndex + 1];
/// <summary>
/// The frame for the start value of the interpolation of the replay movement.
/// </summary>
/// <exception cref="InvalidOperationException">The replay is empty.</exception>
public TFrame StartFrame
{
get
{
if (!HasFrames)
throw new InvalidOperationException($"Attempted to get {nameof(StartFrame)} of an empty replay");
return (TFrame)Frames[Math.Max(0, currentFrameIndex)];
}
}
/// <summary>
/// The frame for the end value of the interpolation of the replay movement.
/// </summary>
/// <exception cref="InvalidOperationException">The replay is empty.</exception>
public TFrame EndFrame
{
get
{
if (!HasFrames)
throw new InvalidOperationException($"Attempted to get {nameof(EndFrame)} of an empty replay");
return (TFrame)Frames[Math.Min(currentFrameIndex + 1, Frames.Count - 1)];
}
}
/// <summary>
/// When set, we will ensure frames executed by nested drawables are frame-accurate to replay data.
/// Disabling this can make replay playback smoother (useful for autoplay, currently).
/// </summary>
public bool FrameAccuratePlayback;
// This input handler should be enabled only if there is at least one replay frame.
public override bool IsActive => HasFrames;
protected double CurrentTime { get; private set; }
protected virtual double AllowedImportantTimeSpan => sixty_frame_time * 1.2;
protected List<ReplayFrame> Frames => replay.Frames;
private readonly Replay replay;
private int currentFrameIndex;
private const double sixty_frame_time = 1000.0 / 60;
protected FramedReplayInputHandler(Replay replay)
{
// TODO: This replay frame ordering should be enforced on the Replay type.
// Currently, the ordering can be broken if the frames are added after this construction.
replay.Frames = replay.Frames.OrderBy(f => f.Time).ToList();
this.replay = replay;
currentFrameIndex = -1;
CurrentTime = double.NegativeInfinity;
}
private bool inImportantSection
{
get
{
if (!HasFrames || !FrameAccuratePlayback || currentFrameIndex == -1)
return false;
return IsImportant(StartFrame) && // a button is in a pressed state
Math.Abs(CurrentTime - EndFrame.Time) <= AllowedImportantTimeSpan; // the next frame is within an allowable time span
}
}
protected virtual bool IsImportant(TFrame frame) => false;
/// <summary>
/// Update the current frame based on an incoming time value.
/// There are cases where we return a "must-use" time value that is different from the input.
/// This is to ensure accurate playback of replay data.
/// </summary>
/// <param name="time">The time which we should use for finding the current frame.</param>
/// <returns>The usable time value. If null, we should not advance time as we do not have enough data.</returns>
public override double? SetFrameFromTime(double time)
{
if (!HasFrames)
{
// In the case all frames are received, allow time to progress regardless.
if (replay.HasReceivedAllFrames)
return CurrentTime = time;
return null;
}
double frameStart = getFrameTime(currentFrameIndex);
double frameEnd = getFrameTime(currentFrameIndex + 1);
// If the proposed time is after the current frame end time, we progress forwards to precisely the new frame's time (regardless of incoming time).
if (frameEnd <= time)
{
time = frameEnd;
currentFrameIndex++;
}
// If the proposed time is before the current frame start time, and we are at the frame boundary, we progress backwards.
else if (time < frameStart && CurrentTime == frameStart)
currentFrameIndex--;
frameStart = getFrameTime(currentFrameIndex);
frameEnd = getFrameTime(currentFrameIndex + 1);
// Pause until more frames are arrived.
if (WaitingForFrame && frameStart < time)
{
CurrentTime = frameStart;
return null;
}
CurrentTime = Math.Clamp(time, frameStart, frameEnd);
// In an important section, a mid-frame time cannot be used and a null is returned instead.
return inImportantSection && frameStart < time && time < frameEnd ? null : (double?)CurrentTime;
}
private double getFrameTime(int index)
{
if (index < 0)
return double.NegativeInfinity;
if (index >= Frames.Count)
return double.PositiveInfinity;
return Frames[index].Time;
}
public sealed override void CollectPendingInputs(List<IInput> inputs)
{
base.CollectPendingInputs(inputs);
CollectReplayInputs(inputs);
if (CurrentFrame?.Header != null)
inputs.Add(new ReplayStatisticsFrameInput { Frame = CurrentFrame });
}
protected virtual void CollectReplayInputs(List<IInput> inputs)
{
}
}
}