Fix incorrect folder name.

osu.Game.Modes.Osu/Objects/Drawables/Pieces/Triangles.cs

@@ -0,0 +1,44 @@
+//Copyright (c) 2007-2016 ppy Pty Ltd <contact@ppy.sh>.
+//Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Sprites;
+using osu.Framework.Graphics.Textures;
+using osu.Framework.MathUtils;
+using OpenTK;
+
+namespace osu.Game.Modes.Osu.Objects.Drawables.Pieces
+{
+    public class Triangles : Container<Triangle>
+    {
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            const float size = 100;
+            for (int i = 0; i < 10; i++)
+            {
+                Add(new Triangle
+                {
+                    Origin = Anchor.Centre,
+                    RelativePositionAxes = Axes.Both,
+                    Position = new Vector2(RNG.NextSingle(), RNG.NextSingle()),
+                    Scale = new Vector2(RNG.NextSingle() * 0.4f + 0.2f),
+                    // Scaling height by 0.866 results in equiangular triangles (== 60° and equal side length)
+                    Size = new Vector2(size, 0.866f * size),
+                    Alpha = RNG.NextSingle() * 0.3f,
+                });
+            }
+        }
+
+        protected override void Update()
+        {
+            base.Update();
+
+            foreach (Drawable d in Children)
+                d.Position -= new Vector2(0, (float)(d.Scale.X * (Time.Elapsed / 2880)));
+        }
+    }
+}