Add the ability to toggle new combo state from composer context menu

osu.Game.Tests/Gameplay/TestSceneHitObjectAccentColour.cs

@@ -81,7 +81,7 @@ namespace osu.Game.Tests.Gameplay
 
         private class TestHitObjectWithCombo : ConvertHitObject, IHasComboInformation
         {
-            public bool NewCombo { get; } = false;
+            public bool NewCombo { get; set; } = false;
             public int ComboOffset { get; } = 0;
 
             public Bindable<int> IndexInCurrentComboBindable { get; } = new Bindable<int>();

osu.Game/Rulesets/Objects/Types/IHasComboInformation.cs

@@ -24,6 +24,11 @@ namespace osu.Game.Rulesets.Objects.Types
         /// </summary>
         int ComboIndex { get; set; }
 
+        /// <summary>
+        /// Whether the HitObject starts a new combo.
+        /// </summary>
+        new bool NewCombo { get; set; }
+
         Bindable<bool> LastInComboBindable { get; }
 
         /// <summary>

osu.Game/Screens/Edit/Compose/Components/SelectionHandler.cs

@@ -20,6 +20,7 @@ using osu.Game.Graphics.UserInterface;
 using osu.Game.Rulesets.Edit;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Drawables;
+using osu.Game.Rulesets.Objects.Types;
 using osuTK;
 
 namespace osu.Game.Screens.Edit.Compose.Components
@@ -268,6 +269,24 @@ namespace osu.Game.Screens.Edit.Compose.Components
             changeHandler?.EndChange();
         }
 
+        public void SetNewCombo(bool state)
+        {
+            changeHandler?.BeginChange();
+
+            foreach (var h in SelectedHitObjects)
+            {
+                var comboInfo = h as IHasComboInformation;
+
+                if (comboInfo == null)
+                    throw new InvalidOperationException($"Tried to change combo state of a {h.GetType()}, which doesn't implement {nameof(IHasComboInformation)}");
+
+                comboInfo.NewCombo = state;
+                EditorBeatmap?.UpdateHitObject(h);
+            }
+
+            changeHandler?.EndChange();
+        }
+
         /// <summary>
         /// Removes a hit sample from all selected <see cref="HitObject"/>s.
         /// </summary>
@@ -297,6 +316,9 @@ namespace osu.Game.Screens.Edit.Compose.Components
 
                 items.AddRange(GetContextMenuItemsForSelection(selectedBlueprints));
 
+                if (selectedBlueprints.All(b => b.HitObject is IHasComboInformation))
+                    items.Add(createNewComboMenuItem());
+
                 if (selectedBlueprints.Count == 1)
                     items.AddRange(selectedBlueprints[0].ContextMenuItems);
 
@@ -326,6 +348,41 @@ namespace osu.Game.Screens.Edit.Compose.Components
         protected virtual IEnumerable<MenuItem> GetContextMenuItemsForSelection(IEnumerable<SelectionBlueprint> selection)
             => Enumerable.Empty<MenuItem>();
 
+        private MenuItem createNewComboMenuItem()
+        {
+            return new TernaryStateMenuItem("New combo", MenuItemType.Standard, setNewComboState)
+            {
+                State = { Value = getHitSampleState() }
+            };
+
+            void setNewComboState(TernaryState state)
+            {
+                switch (state)
+                {
+                    case TernaryState.False:
+                        SetNewCombo(false);
+                        break;
+
+                    case TernaryState.True:
+                        SetNewCombo(true);
+                        break;
+                }
+            }
+
+            TernaryState getHitSampleState()
+            {
+                int countExisting = selectedBlueprints.Select(b => b.HitObject as IHasComboInformation).Count(h => h.NewCombo);
+
+                if (countExisting == 0)
+                    return TernaryState.False;
+
+                if (countExisting < SelectedHitObjects.Count())
+                    return TernaryState.Indeterminate;
+
+                return TernaryState.True;
+            }
+        }
+
         private MenuItem createHitSampleMenuItem(string name, string sampleName)
         {
             return new TernaryStateMenuItem(name, MenuItemType.Standard, setHitSampleState)