From 4e2ae72126c304ccbaa69d9ef170370be53889c2 Mon Sep 17 00:00:00 2001
From: smoogipooo <smoogipooo@gmail.com>
Date: Wed, 12 Apr 2017 12:03:51 +0900
Subject: [PATCH] Implement proper masking support for taiko hit objects.

---
 osu.Game.Modes.Taiko/UI/TaikoPlayfield.cs | 36 ++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/osu.Game.Modes.Taiko/UI/TaikoPlayfield.cs b/osu.Game.Modes.Taiko/UI/TaikoPlayfield.cs
index db3a1bc84e..5e5344eb6f 100644
--- a/osu.Game.Modes.Taiko/UI/TaikoPlayfield.cs
+++ b/osu.Game.Modes.Taiko/UI/TaikoPlayfield.cs
@@ -17,6 +17,7 @@ using osu.Framework.Graphics.Primitives;
 using System.Linq;
 using osu.Game.Modes.Taiko.Objects.Drawables;
 using System;
+using osu.Framework.Graphics.OpenGL;
 
 namespace osu.Game.Modes.Taiko.UI
 {
@@ -111,9 +112,11 @@ namespace osu.Game.Modes.Taiko.UI
                                             Anchor = Anchor.CentreLeft,
                                             Origin = Anchor.Centre,
                                         },
-                                        hitObjectContainer = new Container
+                                        hitObjectContainer = new ExternalMaskingRectangleContainer
                                         {
                                             RelativeSizeAxes = Axes.Both,
+                                            Masking = true,
+                                            MaskingReference = () => this
                                         },
                                         judgementContainer = new Container<DrawableTaikoJudgement>
                                         {
@@ -269,5 +272,36 @@ namespace osu.Game.Modes.Taiko.UI
                 }
             }
         }
+
+        private class ExternalMaskingRectangleContainer : Container
+        {
+            public Func<Drawable> MaskingReference;
+
+            protected override void ApplyDrawNode(DrawNode node)
+            {
+                base.ApplyDrawNode(node);
+
+                Drawable maskingReference = MaskingReference?.Invoke();
+
+                if (MaskingReference == null)
+                    return;
+
+                var cn = node as ContainerDrawNode;
+
+                cn.MaskingInfo = !Masking
+                    ? (MaskingInfo?)null
+                    : new MaskingInfo
+                    {
+                        ScreenSpaceAABB = maskingReference.ScreenSpaceDrawQuad.AABB,
+                        MaskingRect = maskingReference.DrawRectangle,
+                        ToMaskingSpace = cn.MaskingInfo.Value.ToMaskingSpace,
+                        CornerRadius = cn.MaskingInfo.Value.CornerRadius,
+                        BorderThickness = cn.MaskingInfo.Value.BorderThickness,
+                        BorderColour = cn.MaskingInfo.Value.BorderColour,
+                        BlendRange = cn.MaskingInfo.Value.BlendRange,
+                        AlphaExponent = cn.MaskingInfo.Value.AlphaExponent
+                    };
+            }
+        }
     }
 }
\ No newline at end of file