Fix path control points losing curve type on save/reload or undo

osu.Game.Rulesets.Osu.Tests/Editor/TestSceneSliderChangeStates.cs

@@ -0,0 +1,47 @@
+// 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.Linq;
+using NUnit.Framework;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Types;
+using osu.Game.Rulesets.Osu.Objects;
+using osu.Game.Tests.Beatmaps;
+using osuTK;
+
+namespace osu.Game.Rulesets.Osu.Tests.Editor
+{
+ public partial class TestSceneSliderChangeStates : TestSceneOsuEditor
+ {
+ protected override IBeatmap CreateBeatmap(RulesetInfo ruleset) => new TestBeatmap(ruleset, false);
+
+ [TestCase(SplineType.Catmull)]
+ [TestCase(SplineType.BSpline)]
+ [TestCase(SplineType.Linear)]
+ [TestCase(SplineType.PerfectCurve)]
+ public void TestSliderRetainsCurveTypes(SplineType splineType)
+ {
+ Slider? slider = null;
+ PathType pathType = new PathType(splineType);
+
+ AddStep("add slider", () => EditorBeatmap.Add(slider = new Slider
+ {
+ StartTime = 500,
+ Path = new SliderPath(new[]
+ {
+ new PathControlPoint(Vector2.Zero, pathType),
+ new PathControlPoint(new Vector2(200, 0), pathType),
+ })
+ }));
+ AddAssert("slider has correct spline type", () => ((Slider)EditorBeatmap.HitObjects[0]).Path.ControlPoints.All(p => p.Type == pathType));
+ AddStep("remove object", () => EditorBeatmap.Remove(slider));
+ AddAssert("slider removed", () => EditorBeatmap.HitObjects.Count == 0);
+ addUndoSteps();
+ AddAssert("slider not removed", () => EditorBeatmap.HitObjects.Count == 1);
+ AddAssert("slider has correct spline type", () => ((Slider)EditorBeatmap.HitObjects[0]).Path.ControlPoints.All(p => p.Type == pathType));
+ }
+
+ private void addUndoSteps() => AddStep("undo", () => Editor.Undo());
+ }
+}

osu.Game/Beatmaps/Formats/LegacyBeatmapEncoder.cs

@@ -450,7 +450,7 @@ private void addPathData(TextWriter writer, IHasPath pathData, Vector2 position)
  // Explicit segments have a new format in which the type is injected into the middle of the control point string.
  // To preserve compatibility with osu-stable as much as possible, explicit segments with the same type are converted to use implicit segments by duplicating the control point.
  // One exception are consecutive perfect curves, which aren't supported in osu!stable and can lead to decoding issues if encoded as implicit segments
- bool needsExplicitSegment = point.Type != lastType || point.Type == PathType.PERFECT_CURVE;
+ bool needsExplicitSegment = point.Type != lastType || point.Type == PathType.PERFECT_CURVE || i == pathData.Path.ControlPoints.Count - 1;
 
  // Another exception to this is when the last two control points of the last segment were duplicated. This is not a scenario supported by osu!stable.
  // Lazer does not add implicit segments for the last two control points of _any_ explicit segment, so an explicit segment is forced in order to maintain consistency with the decoder.

osu.Game/Rulesets/Objects/Legacy/ConvertHitObjectParser.cs

@@ -351,13 +351,19 @@ private IEnumerable<ArraySegment<PathControlPoint>> convertPoints(PathType type,
  {
  int endPointLength = endPoint == null ? 0 : 1;
 
- if (vertices.Length + endPointLength != 3)
- type = PathType.BEZIER;
- else if (isLinear(points[0], points[1], endPoint ?? points[2]))
+ if (FormatVersion < LegacyBeatmapEncoder.FIRST_LAZER_VERSION)
  {
- // osu-stable special-cased colinear perfect curves to a linear path
- type = PathType.LINEAR;
+ if (vertices.Length + endPointLength != 3)
+ type = PathType.BEZIER;
+ else if (isLinear(points[0], points[1], endPoint ?? points[2]))
+ {
+ // osu-stable special-cased colinear perfect curves to a linear path
+ type = PathType.LINEAR;
+ }
  }
+ else if (vertices.Length + endPointLength > 3)
+ // Lazer supports perfect curves with less than 3 points and colinear points
+ type = PathType.BEZIER;
  }
 
  // The first control point must have a definite type.