Merge pull request #2780 from smoogipoo/timeline-markers

Add centre marker to the editor timeline

osu.Game.Tests/Visual/TestCaseEditorComposeTimeline.cs

@@ -21,7 +21,13 @@ namespace osu.Game.Tests.Visual
     [TestFixture]
     public class TestCaseEditorComposeTimeline : EditorClockTestCase
     {
-        public override IReadOnlyList<Type> RequiredTypes => new[] { typeof(TimelineArea), typeof(Timeline), typeof(TimelineButton) };
+        public override IReadOnlyList<Type> RequiredTypes => new[]
+        {
+            typeof(TimelineArea),
+            typeof(Timeline),
+            typeof(TimelineButton),
+            typeof(CentreMarker)
+        };
 
         [BackgroundDependencyLoader]
         private void load()

osu.Game/Screens/Edit/Screens/Compose/Timeline/CentreMarker.cs

@@ -0,0 +1,52 @@
+// Copyright (c) 2007-2018 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.Shapes;
+using osu.Game.Graphics;
+using OpenTK;
+
+namespace osu.Game.Screens.Edit.Screens.Compose.Timeline
+{
+    public class CentreMarker : CompositeDrawable
+    {
+        private const float triangle_width = 20;
+        private const float triangle_height = 10;
+        private const float bar_width = 2;
+
+        public CentreMarker()
+        {
+            RelativeSizeAxes = Axes.Y;
+            Size = new Vector2(20, 1);
+
+            Anchor = Anchor.Centre;
+            Origin = Anchor.Centre;
+
+            InternalChildren = new Drawable[]
+            {
+                new Box
+                {
+                    Anchor = Anchor.Centre,
+                    Origin = Anchor.Centre,
+                    RelativeSizeAxes = Axes.Y,
+                    Width = bar_width,
+                },
+                new Triangle
+                {
+                    Anchor = Anchor.TopCentre,
+                    Origin = Anchor.BottomCentre,
+                    Size = new Vector2(triangle_width, triangle_height),
+                    Scale = new Vector2(1, -1)
+                }
+            };
+        }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuColour colours)
+        {
+            Colour = colours.Red;
+        }
+    }
+}

osu.Game/Screens/Edit/Screens/Compose/Timeline/Timeline.cs

@@ -42,6 +42,9 @@ namespace osu.Game.Screens.Edit.Screens.Compose.Timeline
                 Depth = float.MaxValue
             };
 
+            // We don't want the centre marker to scroll
+            AddInternal(new CentreMarker());
+
             WaveformVisible.ValueChanged += visible => waveform.FadeTo(visible ? 1 : 0, 200, Easing.OutQuint);
 
             Beatmap.BindTo(beatmap);