Further reduce visibility of triple buffer in GameHost

osu.Framework/Graphics/Veldrid/Batches/VeldridVertexBatch.cs

@@ -17,7 +17,7 @@ internal abstract class VeldridVertexBatch<T> : IVertexBatch<T>
         /// <summary>
         /// Most documentation recommends that three buffers are used to avoid contention.
         ///
-        /// We already have a triple buffer (see <see cref="GameHost.DrawRoots"/>) governing draw nodes.
+        /// We already have a triple buffer governing draw nodes.
         /// In theory we could set this to two, but there's also a global usage of a vertex batch in <see cref="VeldridRenderer"/> (see <see cref="Renderer.DefaultQuadBatch"/>).
         ///
         /// So this is for now an unfortunate memory overhead. Further work could be done to provide

osu.Framework/Platform/GameHost.cs

@@ -451,9 +451,9 @@ protected virtual void OnExited()
             Exited?.Invoke();
         }
 
-        protected TripleBuffer<DrawNode> DrawRoots = new TripleBuffer<DrawNode>();
+        private readonly TripleBuffer<DrawNode> drawRoots = new TripleBuffer<DrawNode>();
 
-        protected Container Root;
+        internal Container Root { get; private set; }
 
         private ulong frameCount;
 
@@ -479,7 +479,7 @@ protected virtual void UpdateFrame()
             Root.UpdateSubTree();
             Root.UpdateSubTreeMasking();
 
-            using (var buffer = DrawRoots.GetForWrite())
+            using (var buffer = drawRoots.GetForWrite())
                 buffer.Object = Root.GenerateDrawNodeSubtree(frameCount, buffer.Index, false);
         }
 
@@ -511,7 +511,7 @@ protected virtual void DrawFrame()
                     Renderer.WaitUntilNextFrameReady();
 
                 didRenderFrame = false;
-                buffer = DrawRoots.GetForRead();
+                buffer = drawRoots.GetForRead();
             }
 
             if (buffer == null)