// 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.Framework.Utils; using osu.Game.Beatmaps; using osu.Game.Beatmaps.ControlPoints; namespace osu.Game.Rulesets.Objects { public class BarLineGenerator<TBarLine> where TBarLine : class, IBarLine, new() { /// <summary> /// The generated bar lines. /// </summary> public readonly List<TBarLine> BarLines = new List<TBarLine>(); /// <summary> /// Constructs and generates bar lines for provided beatmap. /// </summary> /// <param name="beatmap">The beatmap to generate bar lines for.</param> public BarLineGenerator(IBeatmap beatmap) { if (beatmap.HitObjects.Count == 0) return; HitObject lastObject = beatmap.HitObjects.Last(); double lastHitTime = 1 + lastObject.GetEndTime(); var timingPoints = beatmap.ControlPointInfo.TimingPoints; if (timingPoints.Count == 0) return; for (int i = 0; i < timingPoints.Count; i++) { TimingControlPoint currentTimingPoint = timingPoints[i]; int currentBeat = 0; // Stop on the beat before the next timing point, or if there is no next timing point stop slightly past the last object double endTime = i < timingPoints.Count - 1 ? timingPoints[i + 1].Time - currentTimingPoint.BeatLength : lastHitTime + currentTimingPoint.BeatLength * (int)currentTimingPoint.TimeSignature; double barLength = currentTimingPoint.BeatLength * (int)currentTimingPoint.TimeSignature; for (double t = currentTimingPoint.Time; Precision.DefinitelyBigger(endTime, t); t += barLength, currentBeat++) { var roundedTime = Math.Round(t, MidpointRounding.AwayFromZero); // in the case of some bar lengths, rounding errors can cause t to be slightly less than // the expected whole number value due to floating point inaccuracies. // if this is the case, apply rounding. if (Precision.AlmostEquals(t, roundedTime)) { t = roundedTime; } BarLines.Add(new TBarLine { StartTime = t, Major = currentBeat % (int)currentTimingPoint.TimeSignature == 0 }); } } } } }