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clean up code
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@ -152,72 +152,52 @@ namespace osu.Game.Utils
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/// <param name="points">The points to calculate a convex hull.</param>
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public static List<Vector2> GetConvexHull(IEnumerable<Vector2> points)
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{
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// Naming convention implies positive y upwards.
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bool isCCW(Vector2 a, Vector2 b, Vector2 c) => crossProduct(b - a, c - a) > 0;
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float crossProduct(Vector2 v1, Vector2 v2) => v1.X * v2.Y - v1.Y * v2.X;
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var pointsList = points.ToList();
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pointsList.Sort(delegate (Vector2 point1, Vector2 point2)
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{
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if (point1.X == point2.X)
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return point1.Y.CompareTo(point2.Y);
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return point1.X.CompareTo(point2.X);
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});
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var pointsList = points.OrderBy(p => p.X).ThenBy(p => p.Y).ToList();
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if (pointsList.Count < 3)
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return pointsList;
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var convexHullUpper = new List<Vector2>
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var convexHullLower = new List<Vector2>
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{
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pointsList[0],
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pointsList[1]
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};
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var convexHullLower = new List<Vector2>
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var convexHullUpper = new List<Vector2>
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{
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pointsList[pointsList.Count - 1],
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pointsList[pointsList.Count - 2]
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pointsList[^1],
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pointsList[^2]
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};
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for (int i_points = 2; i_points < pointsList.Count; i_points++)
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// Build the lower hull.
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for (int i = 2; i < pointsList.Count; i++)
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{
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Vector2 c = pointsList[i_points];
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for (int i_hull = convexHullUpper.Count - 1; i_hull > 0; i_hull--)
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{
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Vector2 a = convexHullUpper[^2];
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Vector2 b = convexHullUpper[^1];
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if (isCCW(a, b, c))
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convexHullUpper.Remove(b);
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else
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break;
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}
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convexHullUpper.Add(c);
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}
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Vector2 c = pointsList[i];
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while (convexHullLower.Count > 1 && isClockwise(convexHullLower[^2], convexHullLower[^1], c))
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convexHullLower.RemoveAt(convexHullLower.Count - 1);
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for (int i_points = pointsList.Count - 3; i_points >= 0; i_points--)
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{
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Vector2 c = pointsList[i_points];
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for (int i_hull = convexHullLower.Count - 1; i_hull > 0; i_hull--)
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{
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Vector2 a = convexHullLower[^2];
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Vector2 b = convexHullLower[^1];
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if (isCCW(a, b, c))
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convexHullLower.Remove(b);
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else
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break;
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}
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convexHullLower.Add(c);
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}
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convexHullUpper.RemoveAt(convexHullUpper.Count - 1);
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// Build the upper hull.
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for (int i = pointsList.Count - 3; i >= 0; i--)
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{
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Vector2 c = pointsList[i];
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while (convexHullUpper.Count > 1 && isClockwise(convexHullUpper[^2], convexHullUpper[^1], c))
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convexHullUpper.RemoveAt(convexHullUpper.Count - 1);
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convexHullUpper.Add(c);
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}
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convexHullLower.RemoveAt(convexHullLower.Count - 1);
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convexHullUpper.RemoveAt(convexHullUpper.Count - 1);
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convexHullUpper.AddRange(convexHullLower);
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var convexHull = convexHullUpper;
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convexHullLower.AddRange(convexHullUpper);
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return convexHull;
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return convexHullLower;
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float crossProduct(Vector2 v1, Vector2 v2) => v1.X * v2.Y - v1.Y * v2.X;
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bool isClockwise(Vector2 a, Vector2 b, Vector2 c) => crossProduct(b - a, c - a) >= 0;
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}
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public static List<Vector2> GetConvexHull(IEnumerable<IHasPosition> hitObjects) =>
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