Add initial implementation of juice stream placement

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/PlacementEditablePath.cs

@@ -0,0 +1,44 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using osu.Game.Rulesets.Catch.Objects;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints.Components
+{
+    public class PlacementEditablePath : EditablePath
+    {
+        private JuiceStreamPathVertex originalNewVertex;
+
+        public PlacementEditablePath(Func<float, double> positionToDistance)
+            : base(positionToDistance)
+        {
+        }
+
+        public void AddNewVertex()
+        {
+            var endVertex = Vertices[^1];
+            int index = AddVertex(endVertex.Distance, endVertex.X);
+
+            for (int i = 0; i < VertexCount; i++)
+            {
+                VertexStates[i].IsSelected = i == index;
+                VertexStates[i].VertexBeforeChange = Vertices[i];
+            }
+
+            originalNewVertex = Vertices[index];
+        }
+
+        /// <summary>
+        /// Move the vertex added by <see cref="AddNewVertex"/> in the last time.
+        /// </summary>
+        public void MoveLastVertex(Vector2 screenSpacePosition)
+        {
+            Vector2 position = ToRelativePosition(screenSpacePosition);
+            double distanceDelta = PositionToDistance(position.Y) - originalNewVertex.Distance;
+            float xDelta = position.X - originalNewVertex.X;
+            MoveSelectedVertices(distanceDelta, xDelta);
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/JuiceStreamPlacementBlueprint.cs

@@ -1,11 +1,118 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using osu.Framework.Graphics;
+using osu.Framework.Input.Events;
+using osu.Game.Rulesets.Catch.Edit.Blueprints.Components;
 using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Edit;
+using osuTK;
+using osuTK.Input;
 
 namespace osu.Game.Rulesets.Catch.Edit.Blueprints
 {
     public class JuiceStreamPlacementBlueprint : CatchPlacementBlueprint<JuiceStream>
     {
+        private readonly ScrollingPath scrollingPath;
+
+        private readonly NestedOutlineContainer nestedOutlineContainer;
+
+        private readonly PlacementEditablePath editablePath;
+
+        private int lastEditablePathId = -1;
+
+        public JuiceStreamPlacementBlueprint()
+        {
+            InternalChildren = new Drawable[]
+            {
+                scrollingPath = new ScrollingPath(),
+                nestedOutlineContainer = new NestedOutlineContainer(),
+                editablePath = new PlacementEditablePath(positionToDistance)
+            };
+        }
+
+        protected override void Update()
+        {
+            base.Update();
+
+            if (PlacementActive == PlacementState.Active)
+                editablePath.UpdateFrom(HitObjectContainer, HitObject);
+        }
+
+        protected override bool OnMouseDown(MouseDownEvent e)
+        {
+            switch (PlacementActive)
+            {
+                case PlacementState.Waiting:
+                    if (e.Button != MouseButton.Left) break;
+
+                    editablePath.AddNewVertex();
+                    BeginPlacement(true);
+                    return true;
+
+                case PlacementState.Active:
+                    switch (e.Button)
+                    {
+                        case MouseButton.Left:
+                            editablePath.AddNewVertex();
+                            return true;
+
+                        case MouseButton.Right:
+                            EndPlacement(HitObject.Duration > 0);
+                            return true;
+                    }
+
+                    break;
+            }
+
+            return base.OnMouseDown(e);
+        }
+
+        public override void UpdateTimeAndPosition(SnapResult result)
+        {
+            switch (PlacementActive)
+            {
+                case PlacementState.Waiting:
+                    if (!(result.Time is double snappedTime)) return;
+
+                    HitObject.OriginalX = ToLocalSpace(result.ScreenSpacePosition).X;
+                    HitObject.StartTime = snappedTime;
+                    break;
+
+                case PlacementState.Active:
+                    Vector2 unsnappedPosition = GetContainingInputManager().CurrentState.Mouse.Position;
+                    editablePath.MoveLastVertex(unsnappedPosition);
+                    break;
+
+                default:
+                    return;
+            }
+
+            // Make sure the up-to-date position is used for outlines.
+            Vector2 startPosition = CatchHitObjectUtils.GetStartPosition(HitObjectContainer, HitObject);
+            editablePath.Position = nestedOutlineContainer.Position = scrollingPath.Position = startPosition;
+
+            updateHitObjectFromPath();
+        }
+
+        private void updateHitObjectFromPath()
+        {
+            if (lastEditablePathId == editablePath.PathId)
+                return;
+
+            editablePath.UpdateHitObjectFromPath(HitObject);
+            ApplyDefaultsToHitObject();
+
+            scrollingPath.UpdatePathFrom(HitObjectContainer, HitObject);
+            nestedOutlineContainer.UpdateNestedObjectsFrom(HitObjectContainer, HitObject);
+
+            lastEditablePathId = editablePath.PathId;
+        }
+
+        private double positionToDistance(float relativeYPosition)
+        {
+            double time = HitObjectContainer.TimeAtPosition(relativeYPosition, HitObject.StartTime);
+            return (time - HitObject.StartTime) * HitObject.Velocity;
+        }
     }
 }