osu/osu.Game/Rulesets/Objects/SliderPathExtensions.cs

103 lines
4.4 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.
using System.Collections.Generic;
using System.Linq;
using osu.Game.Rulesets.Edit;
using osu.Game.Rulesets.Objects.Types;
using osuTK;
namespace osu.Game.Rulesets.Objects
{
public static class SliderPathExtensions
{
/// <summary>
/// Snaps the provided <paramref name="hitObject"/>'s duration using the <paramref name="snapProvider"/>.
/// </summary>
public static void SnapTo<THitObject>(this THitObject hitObject, IDistanceSnapProvider? snapProvider)
where THitObject : HitObject, IHasPath
{
hitObject.Path.ExpectedDistance.Value = snapProvider?.FindSnappedDistance(hitObject, (float)hitObject.Path.CalculatedDistance) ?? hitObject.Path.CalculatedDistance;
}
/// <summary>
/// Reverse the direction of this path.
/// </summary>
/// <param name="sliderPath">The <see cref="SliderPath"/>.</param>
/// <param name="positionalOffset">The positional offset of the resulting path. It should be added to the start position of this path.</param>
public static void Reverse(this SliderPath sliderPath, out Vector2 positionalOffset)
{
var controlPoints = sliderPath.ControlPoints;
var inheritedLinearPoints = controlPoints.Where(p => sliderPath.PointsInSegment(p)[0].Type == PathType.LINEAR && p.Type is null).ToList();
// Inherited points after a linear point, as well as the first control point if it inherited,
// should be treated as linear points, so their types are temporarily changed to linear.
inheritedLinearPoints.ForEach(p => p.Type = PathType.LINEAR);
double[] segmentEnds = sliderPath.GetSegmentEnds().ToArray();
// Remove segments after the end of the slider.
for (int numSegmentsToRemove = segmentEnds.Count(se => se >= 1) - 1; numSegmentsToRemove > 0 && controlPoints.Count > 0;)
{
if (controlPoints.Last().Type is not null)
{
numSegmentsToRemove--;
segmentEnds = segmentEnds[..^1];
}
controlPoints.RemoveAt(controlPoints.Count - 1);
}
// Restore original control point types.
inheritedLinearPoints.ForEach(p => p.Type = null);
// Recalculate middle perfect curve control points at the end of the slider path.
if (controlPoints.Count >= 3 && controlPoints[^3].Type == PathType.PERFECT_CURVE && controlPoints[^2].Type is null && segmentEnds.Any())
{
double lastSegmentStart = segmentEnds.Length > 1 ? segmentEnds[^2] : 0;
double lastSegmentEnd = segmentEnds[^1];
var circleArcPath = new List<Vector2>();
sliderPath.GetPathToProgress(circleArcPath, lastSegmentStart / lastSegmentEnd, 1);
controlPoints[^2].Position = circleArcPath[circleArcPath.Count / 2];
}
sliderPath.reverseControlPoints(out positionalOffset);
}
/// <summary>
/// Reverses the order of the provided <see cref="SliderPath"/>'s <see cref="PathControlPoint"/>s.
/// </summary>
/// <param name="sliderPath">The <see cref="SliderPath"/>.</param>
/// <param name="positionalOffset">The positional offset of the resulting path. It should be added to the start position of this path.</param>
private static void reverseControlPoints(this SliderPath sliderPath, out Vector2 positionalOffset)
{
var points = sliderPath.ControlPoints.ToArray();
positionalOffset = sliderPath.PositionAt(1);
sliderPath.ControlPoints.Clear();
PathType? lastType = null;
for (int i = 0; i < points.Length; i++)
{
var p = points[i];
p.Position -= positionalOffset;
// propagate types forwards to last null type
if (i == points.Length - 1)
{
p.Type = lastType;
p.Position = Vector2.Zero;
}
else if (p.Type != null)
(p.Type, lastType) = (lastType, p.Type);
sliderPath.ControlPoints.Insert(0, p);
}
}
}
}