From 06af8cb9522fae15daead3c3892301fc5fe1cc46 Mon Sep 17 00:00:00 2001
From: Caiyi Shyu <cai1hsu@outlook.com>
Date: Fri, 2 Aug 2024 16:23:37 +0800
Subject: [PATCH 1/2] interpolate parts in local space to avoid broken trails

---
 .../UI/Cursor/CursorTrail.cs                  | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/osu.Game.Rulesets.Osu/UI/Cursor/CursorTrail.cs b/osu.Game.Rulesets.Osu/UI/Cursor/CursorTrail.cs
index 5e8061bb6a2b..f684bcb58f6c 100644
--- a/osu.Game.Rulesets.Osu/UI/Cursor/CursorTrail.cs
+++ b/osu.Game.Rulesets.Osu/UI/Cursor/CursorTrail.cs
@@ -65,6 +65,7 @@ public CursorTrail()
             }
 
             AddLayout(partSizeCache);
+            AddLayout(scaleRatioCache);
         }
 
         [BackgroundDependencyLoader]
@@ -154,8 +155,16 @@ protected override bool OnMouseMove(MouseMoveEvent e)
             return base.OnMouseMove(e);
         }
 
+        private readonly LayoutValue<Vector2> scaleRatioCache = new LayoutValue<Vector2>(Invalidation.DrawInfo | Invalidation.RequiredParentSizeToFit | Invalidation.Presence);
+
+        private Vector2 scaleRatio => scaleRatioCache.IsValid
+            ? scaleRatioCache.Value
+            : (scaleRatioCache.Value = DrawInfo.MatrixInverse.ExtractScale().Xy);
+
         protected void AddTrail(Vector2 position)
         {
+            position = ToLocalSpace(position);
+
             if (InterpolateMovements)
             {
                 if (!lastPosition.HasValue)
@@ -174,10 +183,10 @@ protected void AddTrail(Vector2 position)
                     float distance = diff.Length;
                     Vector2 direction = diff / distance;
 
-                    float interval = partSize.X / 2.5f * IntervalMultiplier;
-                    float stopAt = distance - (AvoidDrawingNearCursor ? interval : 0);
+                    Vector2 interval = partSize.X / 2.5f * IntervalMultiplier * scaleRatio;
+                    float stopAt = distance - (AvoidDrawingNearCursor ? interval.Length : 0);
 
-                    for (float d = interval; d < stopAt; d += interval)
+                    for (Vector2 d = interval; d.Length < stopAt; d += interval)
                     {
                         lastPosition = pos1 + direction * d;
                         addPart(lastPosition.Value);
@@ -191,9 +200,9 @@ protected void AddTrail(Vector2 position)
             }
         }
 
-        private void addPart(Vector2 screenSpacePosition)
+        private void addPart(Vector2 localSpacePosition)
         {
-            parts[currentIndex].Position = ToLocalSpace(screenSpacePosition);
+            parts[currentIndex].Position = localSpacePosition;
             parts[currentIndex].Time = time + 1;
             ++parts[currentIndex].InvalidationID;
 

From 4b5c163d93d912cd730d07ae9e76eeb7554a04e7 Mon Sep 17 00:00:00 2001
From: Caiyi Shyu <cai1hsu@outlook.com>
Date: Fri, 2 Aug 2024 17:45:05 +0800
Subject: [PATCH 2/2] remove unnecessary LayoutValue

---
 .../UI/Cursor/CursorTrail.cs                  | 22 +++----------------
 1 file changed, 3 insertions(+), 19 deletions(-)

diff --git a/osu.Game.Rulesets.Osu/UI/Cursor/CursorTrail.cs b/osu.Game.Rulesets.Osu/UI/Cursor/CursorTrail.cs
index f684bcb58f6c..6452444fedf1 100644
--- a/osu.Game.Rulesets.Osu/UI/Cursor/CursorTrail.cs
+++ b/osu.Game.Rulesets.Osu/UI/Cursor/CursorTrail.cs
@@ -16,7 +16,6 @@
 using osu.Framework.Graphics.Textures;
 using osu.Framework.Input;
 using osu.Framework.Input.Events;
-using osu.Framework.Layout;
 using osu.Framework.Timing;
 using osuTK;
 using osuTK.Graphics;
@@ -63,9 +62,6 @@ public CursorTrail()
                 // -1 signals that the part is unusable, and should not be drawn
                 parts[i].InvalidationID = -1;
             }
-
-            AddLayout(partSizeCache);
-            AddLayout(scaleRatioCache);
         }
 
         [BackgroundDependencyLoader]
@@ -96,12 +92,6 @@ public Texture Texture
             }
         }
 
-        private readonly LayoutValue<Vector2> partSizeCache = new LayoutValue<Vector2>(Invalidation.DrawInfo | Invalidation.RequiredParentSizeToFit | Invalidation.Presence);
-
-        private Vector2 partSize => partSizeCache.IsValid
-            ? partSizeCache.Value
-            : (partSizeCache.Value = new Vector2(Texture.DisplayWidth, Texture.DisplayHeight) * DrawInfo.Matrix.ExtractScale().Xy);
-
         /// <summary>
         /// The amount of time to fade the cursor trail pieces.
         /// </summary>
@@ -155,12 +145,6 @@ protected override bool OnMouseMove(MouseMoveEvent e)
             return base.OnMouseMove(e);
         }
 
-        private readonly LayoutValue<Vector2> scaleRatioCache = new LayoutValue<Vector2>(Invalidation.DrawInfo | Invalidation.RequiredParentSizeToFit | Invalidation.Presence);
-
-        private Vector2 scaleRatio => scaleRatioCache.IsValid
-            ? scaleRatioCache.Value
-            : (scaleRatioCache.Value = DrawInfo.MatrixInverse.ExtractScale().Xy);
-
         protected void AddTrail(Vector2 position)
         {
             position = ToLocalSpace(position);
@@ -183,10 +167,10 @@ protected void AddTrail(Vector2 position)
                     float distance = diff.Length;
                     Vector2 direction = diff / distance;
 
-                    Vector2 interval = partSize.X / 2.5f * IntervalMultiplier * scaleRatio;
-                    float stopAt = distance - (AvoidDrawingNearCursor ? interval.Length : 0);
+                    float interval = Texture.DisplayWidth / 2.5f * IntervalMultiplier;
+                    float stopAt = distance - (AvoidDrawingNearCursor ? interval : 0);
 
-                    for (Vector2 d = interval; d.Length < stopAt; d += interval)
+                    for (float d = interval; d < stopAt; d += interval)
                     {
                         lastPosition = pos1 + direction * d;
                         addPart(lastPosition.Value);