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Merge pull request #29938 from OliBomby/selection-center
Use minimum enclosing circle as selection centre for scale and rotate
This commit is contained in:
commit
33593280d8
29
osu.Game.Benchmarks/BenchmarkGeometryUtils.cs
Normal file
29
osu.Game.Benchmarks/BenchmarkGeometryUtils.cs
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@ -0,0 +1,29 @@
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// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
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// See the LICENCE file in the repository root for full licence text.
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using BenchmarkDotNet.Attributes;
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using osu.Framework.Utils;
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using osu.Game.Utils;
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using osuTK;
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namespace osu.Game.Benchmarks
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{
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public class BenchmarkGeometryUtils : BenchmarkTest
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{
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[Params(100, 1000, 2000, 4000, 8000, 10000)]
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public int N;
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private Vector2[] points = null!;
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public override void SetUp()
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{
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points = new Vector2[N];
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for (int i = 0; i < points.Length; ++i)
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points[i] = new Vector2(RNG.Next(512), RNG.Next(384));
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}
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[Benchmark]
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public void MinimumEnclosingCircle() => GeometryUtils.MinimumEnclosingCircle(points);
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}
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}
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@ -47,7 +47,6 @@ namespace osu.Game.Rulesets.Osu.Edit
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private OsuHitObject[]? objectsInRotation;
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private OsuHitObject[]? objectsInRotation;
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private Vector2? defaultOrigin;
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private Dictionary<OsuHitObject, Vector2>? originalPositions;
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private Dictionary<OsuHitObject, Vector2>? originalPositions;
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private Dictionary<IHasPath, Vector2[]>? originalPathControlPointPositions;
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private Dictionary<IHasPath, Vector2[]>? originalPathControlPointPositions;
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@ -61,7 +60,7 @@ namespace osu.Game.Rulesets.Osu.Edit
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changeHandler?.BeginChange();
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changeHandler?.BeginChange();
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objectsInRotation = selectedMovableObjects.ToArray();
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objectsInRotation = selectedMovableObjects.ToArray();
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defaultOrigin = GeometryUtils.GetSurroundingQuad(objectsInRotation).Centre;
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DefaultOrigin = GeometryUtils.MinimumEnclosingCircle(objectsInRotation).Item1;
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originalPositions = objectsInRotation.ToDictionary(obj => obj, obj => obj.Position);
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originalPositions = objectsInRotation.ToDictionary(obj => obj, obj => obj.Position);
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originalPathControlPointPositions = objectsInRotation.OfType<IHasPath>().ToDictionary(
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originalPathControlPointPositions = objectsInRotation.OfType<IHasPath>().ToDictionary(
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obj => obj,
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obj => obj,
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@ -73,9 +72,9 @@ namespace osu.Game.Rulesets.Osu.Edit
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if (!OperationInProgress.Value)
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if (!OperationInProgress.Value)
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throw new InvalidOperationException($"Cannot {nameof(Update)} a rotate operation without calling {nameof(Begin)} first!");
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throw new InvalidOperationException($"Cannot {nameof(Update)} a rotate operation without calling {nameof(Begin)} first!");
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Debug.Assert(objectsInRotation != null && originalPositions != null && originalPathControlPointPositions != null && defaultOrigin != null);
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Debug.Assert(objectsInRotation != null && originalPositions != null && originalPathControlPointPositions != null && DefaultOrigin != null);
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Vector2 actualOrigin = origin ?? defaultOrigin.Value;
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Vector2 actualOrigin = origin ?? DefaultOrigin.Value;
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foreach (var ho in objectsInRotation)
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foreach (var ho in objectsInRotation)
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{
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{
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@ -103,7 +102,7 @@ namespace osu.Game.Rulesets.Osu.Edit
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objectsInRotation = null;
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objectsInRotation = null;
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originalPositions = null;
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originalPositions = null;
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originalPathControlPointPositions = null;
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originalPathControlPointPositions = null;
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defaultOrigin = null;
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DefaultOrigin = null;
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}
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}
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private IEnumerable<OsuHitObject> selectedMovableObjects => selectedItems.Cast<OsuHitObject>()
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private IEnumerable<OsuHitObject> selectedMovableObjects => selectedItems.Cast<OsuHitObject>()
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@ -84,10 +84,10 @@ namespace osu.Game.Rulesets.Osu.Edit
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OriginalSurroundingQuad = objectsInScale.Count == 1 && objectsInScale.First().Key is Slider slider
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OriginalSurroundingQuad = objectsInScale.Count == 1 && objectsInScale.First().Key is Slider slider
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? GeometryUtils.GetSurroundingQuad(slider.Path.ControlPoints.Select(p => slider.Position + p.Position))
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? GeometryUtils.GetSurroundingQuad(slider.Path.ControlPoints.Select(p => slider.Position + p.Position))
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: GeometryUtils.GetSurroundingQuad(objectsInScale.Keys);
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: GeometryUtils.GetSurroundingQuad(objectsInScale.Keys);
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defaultOrigin = OriginalSurroundingQuad.Value.Centre;
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originalConvexHull = objectsInScale.Count == 1 && objectsInScale.First().Key is Slider slider2
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originalConvexHull = objectsInScale.Count == 1 && objectsInScale.First().Key is Slider slider2
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? GeometryUtils.GetConvexHull(slider2.Path.ControlPoints.Select(p => slider2.Position + p.Position))
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? GeometryUtils.GetConvexHull(slider2.Path.ControlPoints.Select(p => slider2.Position + p.Position))
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: GeometryUtils.GetConvexHull(objectsInScale.Keys);
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: GeometryUtils.GetConvexHull(objectsInScale.Keys);
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defaultOrigin = GeometryUtils.MinimumEnclosingCircle(originalConvexHull).Item1;
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}
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}
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public override void Update(Vector2 scale, Vector2? origin = null, Axes adjustAxis = Axes.Both, float axisRotation = 0)
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public override void Update(Vector2 scale, Vector2? origin = null, Axes adjustAxis = Axes.Both, float axisRotation = 0)
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@ -29,5 +29,23 @@ namespace osu.Game.Tests.Utils
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Assert.That(hull, Is.EquivalentTo(expectedPoints));
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Assert.That(hull, Is.EquivalentTo(expectedPoints));
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}
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}
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[TestCase(new int[] { }, 0, 0, 0)]
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[TestCase(new[] { 0, 0 }, 0, 0, 0)]
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[TestCase(new[] { 0, 0, 1, 1, 1, -1, 2, 0 }, 1, 0, 1)]
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[TestCase(new[] { 0, 0, 1, 1, 1, -1, 2, 0, 1, 0 }, 1, 0, 1)]
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[TestCase(new[] { 0, 0, 1, 1, 2, -1, 2, 0, 1, 0, 4, 10 }, 3, 4.5f, 5.5901699f)]
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public void TestMinimumEnclosingCircle(int[] values, float x, float y, float r)
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{
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var points = new Vector2[values.Length / 2];
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for (int i = 0; i < values.Length; i += 2)
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points[i / 2] = new Vector2(values[i], values[i + 1]);
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(var centre, float radius) = GeometryUtils.MinimumEnclosingCircle(points);
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Assert.That(centre.X, Is.EqualTo(x).Within(0.0001));
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Assert.That(centre.Y, Is.EqualTo(y).Within(0.0001));
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Assert.That(radius, Is.EqualTo(r).Within(0.0001));
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}
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}
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}
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}
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}
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@ -84,6 +84,7 @@ namespace osu.Game.Tests.Visual.Editing
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targetContainer = getTargetContainer();
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targetContainer = getTargetContainer();
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initialRotation = targetContainer!.Rotation;
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initialRotation = targetContainer!.Rotation;
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DefaultOrigin = ToLocalSpace(targetContainer.ToScreenSpace(Vector2.Zero));
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base.Begin();
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base.Begin();
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}
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}
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@ -46,7 +46,6 @@ namespace osu.Game.Overlays.SkinEditor
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private Drawable[]? objectsInRotation;
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private Drawable[]? objectsInRotation;
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private Vector2? defaultOrigin;
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private Dictionary<Drawable, float>? originalRotations;
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private Dictionary<Drawable, float>? originalRotations;
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private Dictionary<Drawable, Vector2>? originalPositions;
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private Dictionary<Drawable, Vector2>? originalPositions;
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@ -60,7 +59,7 @@ namespace osu.Game.Overlays.SkinEditor
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objectsInRotation = selectedItems.Cast<Drawable>().ToArray();
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objectsInRotation = selectedItems.Cast<Drawable>().ToArray();
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originalRotations = objectsInRotation.ToDictionary(d => d, d => d.Rotation);
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originalRotations = objectsInRotation.ToDictionary(d => d, d => d.Rotation);
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originalPositions = objectsInRotation.ToDictionary(d => d, d => d.ToScreenSpace(d.OriginPosition));
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originalPositions = objectsInRotation.ToDictionary(d => d, d => d.ToScreenSpace(d.OriginPosition));
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defaultOrigin = GeometryUtils.GetSurroundingQuad(objectsInRotation.SelectMany(d => d.ScreenSpaceDrawQuad.GetVertices().ToArray())).Centre;
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DefaultOrigin = GeometryUtils.GetSurroundingQuad(objectsInRotation.SelectMany(d => d.ScreenSpaceDrawQuad.GetVertices().ToArray())).Centre;
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base.Begin();
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base.Begin();
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}
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}
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@ -70,7 +69,7 @@ namespace osu.Game.Overlays.SkinEditor
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if (objectsInRotation == null)
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if (objectsInRotation == null)
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throw new InvalidOperationException($"Cannot {nameof(Update)} a rotate operation without calling {nameof(Begin)} first!");
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throw new InvalidOperationException($"Cannot {nameof(Update)} a rotate operation without calling {nameof(Begin)} first!");
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Debug.Assert(originalRotations != null && originalPositions != null && defaultOrigin != null);
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Debug.Assert(originalRotations != null && originalPositions != null && DefaultOrigin != null);
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if (objectsInRotation.Length == 1 && origin == null)
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if (objectsInRotation.Length == 1 && origin == null)
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{
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{
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@ -79,7 +78,7 @@ namespace osu.Game.Overlays.SkinEditor
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return;
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return;
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}
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}
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var actualOrigin = origin ?? defaultOrigin.Value;
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var actualOrigin = origin ?? DefaultOrigin.Value;
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foreach (var drawableItem in objectsInRotation)
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foreach (var drawableItem in objectsInRotation)
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{
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{
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@ -100,7 +99,7 @@ namespace osu.Game.Overlays.SkinEditor
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objectsInRotation = null;
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objectsInRotation = null;
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originalPositions = null;
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originalPositions = null;
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originalRotations = null;
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originalRotations = null;
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defaultOrigin = null;
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DefaultOrigin = null;
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base.Commit();
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base.Commit();
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}
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}
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@ -67,7 +67,7 @@ namespace osu.Game.Overlays.SkinEditor
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objectsInScale = selectedItems.Cast<Drawable>().ToDictionary(d => d, d => new OriginalDrawableState(d));
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objectsInScale = selectedItems.Cast<Drawable>().ToDictionary(d => d, d => new OriginalDrawableState(d));
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OriginalSurroundingQuad = ToLocalSpace(GeometryUtils.GetSurroundingQuad(objectsInScale.SelectMany(d => d.Key.ScreenSpaceDrawQuad.GetVertices().ToArray())));
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OriginalSurroundingQuad = ToLocalSpace(GeometryUtils.GetSurroundingQuad(objectsInScale.SelectMany(d => d.Key.ScreenSpaceDrawQuad.GetVertices().ToArray())));
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defaultOrigin = OriginalSurroundingQuad.Value.Centre;
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defaultOrigin = ToLocalSpace(GeometryUtils.MinimumEnclosingCircle(objectsInScale.SelectMany(d => d.Key.ScreenSpaceDrawQuad.GetVertices().ToArray())).Item1);
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isFlippedX = false;
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isFlippedX = false;
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isFlippedY = false;
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isFlippedY = false;
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@ -77,6 +77,8 @@ namespace osu.Game.Screens.Edit.Compose.Components
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{
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{
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base.OnDrag(e);
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base.OnDrag(e);
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if (rotationHandler == null || !rotationHandler.OperationInProgress.Value) return;
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rawCumulativeRotation += convertDragEventToAngleOfRotation(e);
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rawCumulativeRotation += convertDragEventToAngleOfRotation(e);
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applyRotation(shouldSnap: e.ShiftPressed);
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applyRotation(shouldSnap: e.ShiftPressed);
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@ -113,9 +115,11 @@ namespace osu.Game.Screens.Edit.Compose.Components
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private float convertDragEventToAngleOfRotation(DragEvent e)
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private float convertDragEventToAngleOfRotation(DragEvent e)
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{
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{
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// Adjust coordinate system to the center of SelectionBox
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// Adjust coordinate system to the center of the selection
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float startAngle = MathF.Atan2(e.LastMousePosition.Y - selectionBox.DrawHeight / 2, e.LastMousePosition.X - selectionBox.DrawWidth / 2);
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Vector2 center = selectionBox.ToLocalSpace(rotationHandler!.ToScreenSpace(rotationHandler!.DefaultOrigin!.Value));
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float endAngle = MathF.Atan2(e.MousePosition.Y - selectionBox.DrawHeight / 2, e.MousePosition.X - selectionBox.DrawWidth / 2);
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float startAngle = MathF.Atan2(e.LastMousePosition.Y - center.Y, e.LastMousePosition.X - center.X);
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float endAngle = MathF.Atan2(e.MousePosition.Y - center.Y, e.MousePosition.X - center.X);
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return (endAngle - startAngle) * 180 / MathF.PI;
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return (endAngle - startAngle) * 180 / MathF.PI;
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}
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}
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@ -13,7 +13,7 @@ namespace osu.Game.Screens.Edit.Compose.Components
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public partial class SelectionRotationHandler : Component
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public partial class SelectionRotationHandler : Component
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{
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{
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/// <summary>
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/// <summary>
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/// Whether there is any ongoing scale operation right now.
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/// Whether there is any ongoing rotation operation right now.
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/// </summary>
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/// </summary>
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public Bindable<bool> OperationInProgress { get; private set; } = new BindableBool();
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public Bindable<bool> OperationInProgress { get; private set; } = new BindableBool();
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@ -27,6 +27,12 @@ namespace osu.Game.Screens.Edit.Compose.Components
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/// </summary>
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/// </summary>
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public Bindable<bool> CanRotateAroundPlayfieldOrigin { get; private set; } = new BindableBool();
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public Bindable<bool> CanRotateAroundPlayfieldOrigin { get; private set; } = new BindableBool();
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/// <summary>
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/// Implementation-defined origin point to rotate around when no explicit origin is provided.
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/// This field is only assigned during a rotation operation.
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/// </summary>
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public Vector2? DefaultOrigin { get; protected set; }
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/// <summary>
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/// <summary>
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/// Performs a single, instant, atomic rotation operation.
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/// Performs a single, instant, atomic rotation operation.
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/// </summary>
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/// </summary>
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@ -6,6 +6,7 @@ using System.Collections.Generic;
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using System.Linq;
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using System.Linq;
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using osu.Framework.Graphics;
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using osu.Framework.Graphics;
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using osu.Framework.Graphics.Primitives;
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using osu.Framework.Graphics.Primitives;
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using osu.Framework.Utils;
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using osu.Game.Rulesets.Objects.Types;
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using osu.Game.Rulesets.Objects.Types;
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using osuTK;
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using osuTK;
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@ -218,5 +219,158 @@ namespace osu.Game.Utils
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return new[] { h.Position };
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return new[] { h.Position };
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});
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});
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#region Welzl helpers
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// Function to check whether a point lies inside or on the boundaries of the circle
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private static bool isInside((Vector2 Centre, float Radius) c, Vector2 p)
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{
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return Precision.AlmostBigger(c.Radius, Vector2.Distance(c.Centre, p));
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}
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// Function to return a unique circle that intersects three points
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private static (Vector2, float) circleFrom(Vector2 a, Vector2 b, Vector2 c)
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{
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if (Precision.AlmostEquals(0, (b.Y - a.Y) * (c.X - a.X) - (b.X - a.X) * (c.Y - a.Y)))
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return circleFrom(a, b);
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// See: https://en.wikipedia.org/wiki/Circumcircle#Cartesian_coordinates
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float d = 2 * (a.X * (b - c).Y + b.X * (c - a).Y + c.X * (a - b).Y);
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float aSq = a.LengthSquared;
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float bSq = b.LengthSquared;
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float cSq = c.LengthSquared;
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var centre = new Vector2(
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aSq * (b - c).Y + bSq * (c - a).Y + cSq * (a - b).Y,
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aSq * (c - b).X + bSq * (a - c).X + cSq * (b - a).X) / d;
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return (centre, Vector2.Distance(a, centre));
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}
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// Function to return the smallest circle that intersects 2 points
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private static (Vector2, float) circleFrom(Vector2 a, Vector2 b)
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{
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var centre = (a + b) / 2.0f;
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return (centre, Vector2.Distance(a, b) / 2.0f);
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}
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// Function to check whether a circle encloses the given points
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private static bool isValidCircle((Vector2, float) c, List<Vector2> points)
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{
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// Iterating through all the points to check whether the points lie inside the circle or not
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foreach (Vector2 p in points)
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{
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if (!isInside(c, p)) return false;
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}
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return true;
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}
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// Function to return the minimum enclosing circle for N <= 3
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private static (Vector2, float) minCircleTrivial(List<Vector2> points)
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{
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if (points.Count > 3)
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|
throw new ArgumentException("Number of points must be at most 3", nameof(points));
|
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switch (points.Count)
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{
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case 0:
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return (new Vector2(0, 0), 0);
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case 1:
|
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return (points[0], 0);
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case 2:
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return circleFrom(points[0], points[1]);
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}
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||||||
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|
||||||
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// To check if MEC can be determined by 2 points only
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for (int i = 0; i < 3; i++)
|
||||||
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{
|
||||||
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for (int j = i + 1; j < 3; j++)
|
||||||
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{
|
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var c = circleFrom(points[i], points[j]);
|
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|
||||||
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if (isValidCircle(c, points))
|
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|
return c;
|
||||||
|
}
|
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}
|
||||||
|
|
||||||
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return circleFrom(points[0], points[1], points[2]);
|
||||||
|
}
|
||||||
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|
||||||
|
#endregion
|
||||||
|
|
||||||
|
/// <summary>
|
||||||
|
/// Function to find the minimum enclosing circle for a collection of points.
|
||||||
|
/// </summary>
|
||||||
|
/// <returns>A tuple containing the circle centre and radius.</returns>
|
||||||
|
public static (Vector2, float) MinimumEnclosingCircle(IEnumerable<Vector2> points)
|
||||||
|
{
|
||||||
|
// Using Welzl's algorithm to find the minimum enclosing circle
|
||||||
|
// https://www.geeksforgeeks.org/minimum-enclosing-circle-using-welzls-algorithm/
|
||||||
|
List<Vector2> p = points.ToList();
|
||||||
|
|
||||||
|
var stack = new Stack<(Vector2?, int)>();
|
||||||
|
var r = new List<Vector2>(3);
|
||||||
|
(Vector2, float) d = (Vector2.Zero, 0);
|
||||||
|
|
||||||
|
stack.Push((null, p.Count));
|
||||||
|
|
||||||
|
while (stack.Count > 0)
|
||||||
|
{
|
||||||
|
// `n` represents the number of points in P that are not yet processed.
|
||||||
|
// `point` represents the point that was randomly picked to process.
|
||||||
|
(Vector2? point, int n) = stack.Pop();
|
||||||
|
|
||||||
|
if (!point.HasValue)
|
||||||
|
{
|
||||||
|
// Base case when all points processed or |R| = 3
|
||||||
|
if (n == 0 || r.Count == 3)
|
||||||
|
{
|
||||||
|
d = minCircleTrivial(r);
|
||||||
|
continue;
|
||||||
|
}
|
||||||
|
|
||||||
|
// Pick a random point randomly
|
||||||
|
int idx = RNG.Next(n);
|
||||||
|
point = p[idx];
|
||||||
|
|
||||||
|
// Put the picked point at the end of P since it's more efficient than
|
||||||
|
// deleting from the middle of the list
|
||||||
|
(p[idx], p[n - 1]) = (p[n - 1], p[idx]);
|
||||||
|
|
||||||
|
// Schedule processing of p after we get the MEC circle d from the set of points P - {p}
|
||||||
|
stack.Push((point, n));
|
||||||
|
// Get the MEC circle d from the set of points P - {p}
|
||||||
|
stack.Push((null, n - 1));
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
// If d contains p, return d
|
||||||
|
if (isInside(d, point.Value))
|
||||||
|
continue;
|
||||||
|
|
||||||
|
// Remove points from R that were added in a deeper recursion
|
||||||
|
// |R| = |P| - |stack| - n
|
||||||
|
int removeCount = r.Count - (p.Count - stack.Count - n);
|
||||||
|
r.RemoveRange(r.Count - removeCount, removeCount);
|
||||||
|
|
||||||
|
// Otherwise, must be on the boundary of the MEC
|
||||||
|
r.Add(point.Value);
|
||||||
|
// Return the MEC for P - {p} and R U {p}
|
||||||
|
stack.Push((null, n - 1));
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
return d;
|
||||||
|
}
|
||||||
|
|
||||||
|
/// <summary>
|
||||||
|
/// Function to find the minimum enclosing circle for a collection of hit objects.
|
||||||
|
/// </summary>
|
||||||
|
/// <returns>A tuple containing the circle centre and radius.</returns>
|
||||||
|
public static (Vector2, float) MinimumEnclosingCircle(IEnumerable<IHasPosition> hitObjects) =>
|
||||||
|
MinimumEnclosingCircle(enumerateStartAndEndPositions(hitObjects));
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
Loading…
Reference in New Issue
Block a user