Inital commit

10 files changed, 1261 insertions, 0 deletions

diff --git a/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/ISelectable.cs b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/ISelectable.cs
new file mode 100644
index 0000000..5f312c1
--- /dev/null
+++ b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/ISelectable.cs
@@ -0,0 +1,11 @@
+using System;
+
+namespace UnityEditor.Timeline
+{
+    interface ISelectable : ILayerable
+    {
+        void Select();
+        bool IsSelected();
+        void Deselect();
+    }
+}
diff --git a/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/ISelectable.cs.meta b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/ISelectable.cs.meta
new file mode 100644
index 0000000..970ecaa
--- /dev/null
+++ b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/ISelectable.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 4acbfc0398bab674f922f693e58f4afc
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineClipGUI.cs b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineClipGUI.cs
new file mode 100644
index 0000000..7d00228
--- /dev/null
+++ b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineClipGUI.cs
@@ -0,0 +1,760 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using UnityEngine;
+using UnityEngine.Playables;
+using UnityEngine.Timeline;
+
+namespace UnityEditor.Timeline
+{
+    class TimelineClipGUI : TimelineItemGUI, IClipCurveEditorOwner, ISnappable, IAttractable
+    {
+        EditorClip m_EditorItem;
+
+        Rect m_ClipCenterSection;
+        readonly List<Rect> m_LoopRects = new List<Rect>();
+
+        ClipDrawData m_ClipDrawData;
+        Rect m_MixOutRect = new Rect();
+        Rect m_MixInRect = new Rect();
+        int m_MinLoopIndex = 1;
+
+        // clip dirty detection
+        int m_LastDirtyIndex = Int32.MinValue;
+        bool m_ClipViewDirty = true;
+
+        bool supportResize { get; }
+        public ClipCurveEditor clipCurveEditor { get; set; }
+        public TimelineClipGUI previousClip { get; set; }
+        public TimelineClipGUI nextClip { get; set; }
+
+        static readonly float k_MinMixWidth = 2;
+        static readonly float k_MaxHandleWidth = 10f;
+        static readonly float k_MinHandleWidth = 1f;
+
+        bool? m_ShowDrillIcon;
+        ClipEditor m_ClipEditor;
+
+        static List<PlayableDirector> s_TempSubDirectors = new List<PlayableDirector>();
+
+        static readonly IconData k_DiggableClipIcon = new IconData(DirectorStyles.LoadIcon("TimelineDigIn"));
+
+        string name
+        {
+            get
+            {
+                if (string.IsNullOrEmpty(clip.displayName))
+                    return "(Empty)";
+
+                return clip.displayName;
+            }
+        }
+
+        public bool inlineCurvesSelected
+        {
+            get { return SelectionManager.IsCurveEditorFocused(this); }
+            set
+            {
+                if (!value && SelectionManager.IsCurveEditorFocused(this))
+                    SelectionManager.SelectInlineCurveEditor(null);
+                else
+                    SelectionManager.SelectInlineCurveEditor(this);
+            }
+        }
+
+        public Rect mixOutRect
+        {
+            get
+            {
+                var percent = clip.mixOutPercentage;
+                var x = Mathf.Round(treeViewRect.width * (1 - percent));
+                var width = Mathf.Round(treeViewRect.width * percent);
+                m_MixOutRect.Set(x, 0.0f, width, treeViewRect.height);
+                return m_MixOutRect;
+            }
+        }
+
+        public Rect mixInRect
+        {
+            get
+            {
+                var width = Mathf.Round(treeViewRect.width * clip.mixInPercentage);
+                m_MixInRect.Set(0.0f, 0.0f, width, treeViewRect.height);
+                return m_MixInRect;
+            }
+        }
+
+        public ClipBlends GetClipBlends()
+        {
+            var _mixInRect = mixInRect;
+            var _mixOutRect = mixOutRect;
+
+            var blendInKind = BlendKind.None;
+            if (_mixInRect.width > k_MinMixWidth && clip.hasBlendIn)
+                blendInKind = BlendKind.Mix;
+            else if (_mixInRect.width > k_MinMixWidth)
+                blendInKind = BlendKind.Ease;
+
+            var blendOutKind = BlendKind.None;
+            if (_mixOutRect.width > k_MinMixWidth && clip.hasBlendOut)
+                blendOutKind = BlendKind.Mix;
+            else if (_mixOutRect.width > k_MinMixWidth)
+                blendOutKind = BlendKind.Ease;
+
+            return new ClipBlends(blendInKind, _mixInRect, blendOutKind, _mixOutRect);
+        }
+
+        public override double start
+        {
+            get { return clip.start; }
+        }
+
+        public override double end
+        {
+            get { return clip.end; }
+        }
+
+        public bool supportsLooping
+        {
+            get { return clip.SupportsLooping(); }
+        }
+
+        // for the inline curve editor, only show loops if we recorded the asset
+        bool IClipCurveEditorOwner.showLoops
+        {
+            get { return clip.SupportsLooping() && (clip.asset is AnimationPlayableAsset);  }
+        }
+
+        TrackAsset IClipCurveEditorOwner.owner
+        {
+            get { return clip.parentTrack; }
+        }
+
+        public bool supportsSubTimelines
+        {
+            get { return m_ClipEditor.supportsSubTimelines; }
+        }
+
+
+        public int minLoopIndex
+        {
+            get { return m_MinLoopIndex; }
+        }
+
+        public TrackDrawer drawer
+        {
+            get { return ((TimelineTrackGUI)parent).drawer; }
+        }
+
+        public Rect clippedRect { get; private set; }
+
+        public override void Select()
+        {
+            zOrder = zOrderProvider.Next();
+            SelectionManager.Add(clip);
+        }
+
+        public override bool IsSelected()
+        {
+            return SelectionManager.Contains(clip);
+        }
+
+        public override void Deselect()
+        {
+            SelectionManager.Remove(clip);
+        }
+
+        public override ITimelineItem item
+        {
+            get { return ItemsUtils.ToItem(clip); }
+        }
+
+        IZOrderProvider zOrderProvider { get; }
+
+        public TimelineClipHandle leftHandle { get; }
+        public TimelineClipHandle rightHandle { get; }
+
+        public TimelineClipGUI(TimelineClip clip, IRowGUI parent, IZOrderProvider provider) : base(parent)
+        {
+            zOrderProvider = provider;
+            zOrder = provider.Next();
+
+            m_EditorItem = EditorClipFactory.GetEditorClip(clip);
+            m_ClipEditor = CustomTimelineEditorCache.GetClipEditor(clip);
+
+            supportResize = true;
+
+            leftHandle = new TimelineClipHandle(this, TrimEdge.Start);
+            rightHandle = new TimelineClipHandle(this, TrimEdge.End);
+
+            ItemToItemGui.Add(clip, this);
+        }
+
+        void CreateInlineCurveEditor(WindowState state)
+        {
+            if (clipCurveEditor != null)
+                return;
+
+            var animationClip = clip.animationClip;
+
+            if (animationClip != null && animationClip.empty)
+                animationClip = null;
+
+            // prune out clips coming from FBX
+            if (animationClip != null && !clip.recordable)
+                return; // don't show, even if there are curves
+
+            if (animationClip == null && !clip.HasAnyAnimatableParameters())
+                return; // nothing to show
+
+            state.AddEndFrameDelegate((istate, currentEvent) =>
+            {
+                clipCurveEditor = new ClipCurveEditor(CurveDataSource.Create(this), TimelineWindow.instance, clip.parentTrack);
+                return true;
+            });
+        }
+
+        public TimelineClip clip
+        {
+            get { return m_EditorItem.clip; }
+        }
+
+        // Draw the actual clip. Defers to the track drawer for customization
+        void UpdateDrawData(WindowState state, Rect drawRect, string title, bool selected, bool previousClipSelected, float rectXOffset)
+        {
+            m_ClipDrawData.clip = clip;
+            m_ClipDrawData.targetRect = drawRect;
+            m_ClipDrawData.clipCenterSection = m_ClipCenterSection;
+            m_ClipDrawData.unclippedRect = treeViewRect;
+            m_ClipDrawData.title = title;
+            m_ClipDrawData.selected = selected;
+            m_ClipDrawData.inlineCurvesSelected = inlineCurvesSelected;
+            m_ClipDrawData.previousClip = previousClip != null ? previousClip.clip : null;
+            m_ClipDrawData.previousClipSelected = previousClipSelected;
+
+            Vector3 shownAreaTime = state.timeAreaShownRange;
+            m_ClipDrawData.localVisibleStartTime = clip.ToLocalTimeUnbound(Math.Max(clip.start, shownAreaTime.x));
+            m_ClipDrawData.localVisibleEndTime = clip.ToLocalTimeUnbound(Math.Min(clip.end, shownAreaTime.y));
+
+            m_ClipDrawData.clippedRect = new Rect(clippedRect.x - rectXOffset, 0.0f, clippedRect.width, clippedRect.height);
+
+            m_ClipDrawData.minLoopIndex = minLoopIndex;
+            m_ClipDrawData.loopRects = m_LoopRects;
+            m_ClipDrawData.supportsLooping = supportsLooping;
+            m_ClipDrawData.clipBlends = GetClipBlends();
+            m_ClipDrawData.clipEditor = m_ClipEditor;
+            m_ClipDrawData.ClipDrawOptions = UpdateClipDrawOptions(m_ClipEditor, clip);
+
+            UpdateClipIcons(state);
+        }
+
+        void UpdateClipIcons(WindowState state)
+        {
+            // Pass 1 - gather size
+            int required = 0;
+            bool requiresDigIn = ShowDrillIcon(state.editSequence.director);
+            if (requiresDigIn)
+                required++;
+
+            var icons = m_ClipDrawData.ClipDrawOptions.icons;
+            foreach (var icon in icons)
+            {
+                if (icon != null)
+                    required++;
+            }
+
+            // Pass 2 - copy icon data
+            if (required == 0)
+            {
+                m_ClipDrawData.rightIcons = null;
+                return;
+            }
+
+            if (m_ClipDrawData.rightIcons == null || m_ClipDrawData.rightIcons.Length != required)
+                m_ClipDrawData.rightIcons = new IconData[required];
+
+            int index = 0;
+            if (requiresDigIn)
+                m_ClipDrawData.rightIcons[index++] = k_DiggableClipIcon;
+
+            foreach (var icon in icons)
+            {
+                if (icon != null)
+                    m_ClipDrawData.rightIcons[index++] = new IconData(icon);
+            }
+        }
+
+        static ClipDrawOptions UpdateClipDrawOptions(ClipEditor clipEditor, TimelineClip clip)
+        {
+            try
+            {
+                return clipEditor.GetClipOptions(clip);
+            }
+            catch (Exception e)
+            {
+                Debug.LogException(e);
+            }
+
+            return CustomTimelineEditorCache.GetDefaultClipEditor().GetClipOptions(clip);
+        }
+
+        static void DrawClip(ClipDrawData drawData)
+        {
+            ClipDrawer.DrawDefaultClip(drawData);
+
+            if (drawData.clip.asset is AnimationPlayableAsset)
+            {
+                var state = TimelineWindow.instance.state;
+                if (state.recording && state.IsArmedForRecord(drawData.clip.parentTrack))
+                {
+                    ClipDrawer.DrawAnimationRecordBorder(drawData);
+                    ClipDrawer.DrawRecordProhibited(drawData);
+                }
+            }
+        }
+
+        public void DrawGhostClip(Rect targetRect)
+        {
+            DrawSimpleClip(targetRect, ClipBorder.Selection(), new Color(1.0f, 1.0f, 1.0f, 0.5f));
+        }
+
+        public void DrawInvalidClip(Rect targetRect)
+        {
+            DrawSimpleClip(targetRect, ClipBorder.Selection(), DirectorStyles.Instance.customSkin.colorInvalidClipOverlay);
+        }
+
+        void DrawSimpleClip(Rect targetRect, ClipBorder border, Color overlay)
+        {
+            var drawOptions = UpdateClipDrawOptions(CustomTimelineEditorCache.GetClipEditor(clip), clip);
+            ClipDrawer.DrawSimpleClip(clip, targetRect, border, overlay, drawOptions);
+        }
+
+        void DrawInto(Rect drawRect, WindowState state)
+        {
+            if (Event.current.type != EventType.Repaint)
+                return;
+
+            // create the inline curve editor if not already created
+            CreateInlineCurveEditor(state);
+
+            // @todo optimization, most of the calculations (rect, offsets, colors, etc.) could be cached
+            // and rebuilt when the hash of the clip changes.
+
+            if (isInvalid)
+            {
+                DrawInvalidClip(treeViewRect);
+                return;
+            }
+
+            GUI.BeginClip(drawRect);
+
+            var originRect = new Rect(0.0f, 0.0f, drawRect.width, drawRect.height);
+            string clipLabel = name;
+            var selected = SelectionManager.Contains(clip);
+            var previousClipSelected = previousClip != null && SelectionManager.Contains(previousClip.clip);
+
+            if (selected && 1.0 != clip.timeScale)
+                clipLabel += " " + clip.timeScale.ToString("F2") + "x";
+
+            UpdateDrawData(state, originRect, clipLabel, selected, previousClipSelected, drawRect.x);
+            DrawClip(m_ClipDrawData);
+
+            GUI.EndClip();
+
+            if (clip.parentTrack != null && !clip.parentTrack.lockedInHierarchy)
+            {
+                if (selected && supportResize)
+                {
+                    var cursorRect = rect;
+                    cursorRect.xMin += leftHandle.boundingRect.width;
+                    cursorRect.xMax -= rightHandle.boundingRect.width;
+                    EditorGUIUtility.AddCursorRect(cursorRect, MouseCursor.MoveArrow);
+                }
+
+                if (supportResize)
+                {
+                    var handleWidth = Mathf.Clamp(drawRect.width * 0.3f, k_MinHandleWidth, k_MaxHandleWidth);
+
+                    leftHandle.Draw(drawRect, handleWidth, state);
+                    rightHandle.Draw(drawRect, handleWidth, state);
+                }
+            }
+        }
+
+        void CalculateClipRectangle(Rect trackRect, WindowState state)
+        {
+            if (m_ClipViewDirty)
+            {
+                var clipRect = RectToTimeline(trackRect, state);
+                treeViewRect = clipRect;
+
+                // calculate clipped rect
+                clipRect.xMin = Mathf.Max(clipRect.xMin, trackRect.xMin);
+                clipRect.xMax = Mathf.Min(clipRect.xMax, trackRect.xMax);
+
+                if (clipRect.width > 0 && clipRect.width < 2)
+                {
+                    clipRect.width = 5.0f;
+                }
+
+                clippedRect = clipRect;
+            }
+        }
+
+        void AddToSpacePartitioner(WindowState state)
+        {
+            if (Event.current.type == EventType.Repaint && !parent.locked)
+                state.spacePartitioner.AddBounds(this, rect);
+        }
+
+        void CalculateBlendRect()
+        {
+            m_ClipCenterSection = treeViewRect;
+            m_ClipCenterSection.x = 0;
+            m_ClipCenterSection.y = 0;
+
+            m_ClipCenterSection.xMin = Mathf.Round(treeViewRect.width * clip.mixInPercentage);
+            m_ClipCenterSection.width = Mathf.Round(treeViewRect.width);
+            m_ClipCenterSection.xMax -= Mathf.Round(mixOutRect.width + treeViewRect.width * clip.mixInPercentage);
+        }
+
+        // Entry point to the Clip Drawing...
+        public override void Draw(Rect trackRect, bool trackRectChanged, WindowState state)
+        {
+            // if the clip has changed, fire the appropriate callback
+            DetectClipChanged(trackRectChanged);
+
+            // update the clip projected rectangle on the timeline
+            CalculateClipRectangle(trackRect, state);
+
+            AddToSpacePartitioner(state);
+
+            // update the blend rects (when clip overlaps with others)
+            CalculateBlendRect();
+
+            // update the loop rects (when clip loops)
+            CalculateLoopRects(trackRect, state);
+
+            DrawExtrapolation(trackRect, treeViewRect);
+
+            DrawInto(treeViewRect, state);
+
+            ResetClipChanged();
+        }
+
+        void DetectClipChanged(bool trackRectChanged)
+        {
+            if (Event.current.type == EventType.Layout)
+            {
+                if (clip.DirtyIndex != m_LastDirtyIndex)
+                {
+                    m_ClipViewDirty = true;
+
+                    try
+                    {
+                        m_ClipEditor.OnClipChanged(clip);
+                    }
+                    catch (Exception e)
+                    {
+                        Debug.LogException(e);
+                    }
+
+                    m_LastDirtyIndex = clip.DirtyIndex;
+                }
+                m_ClipViewDirty |= trackRectChanged;
+            }
+        }
+
+        void ResetClipChanged()
+        {
+            if (Event.current.type == EventType.Repaint)
+                m_ClipViewDirty = false;
+        }
+
+        GUIStyle GetExtrapolationIcon(TimelineClip.ClipExtrapolation mode)
+        {
+            GUIStyle extrapolationIcon = null;
+
+            switch (mode)
+            {
+                case TimelineClip.ClipExtrapolation.None: return null;
+                case TimelineClip.ClipExtrapolation.Hold: extrapolationIcon = m_Styles.extrapolationHold; break;
+                case TimelineClip.ClipExtrapolation.Loop: extrapolationIcon = m_Styles.extrapolationLoop; break;
+                case TimelineClip.ClipExtrapolation.PingPong: extrapolationIcon = m_Styles.extrapolationPingPong; break;
+                case TimelineClip.ClipExtrapolation.Continue: extrapolationIcon = m_Styles.extrapolationContinue; break;
+            }
+
+            return extrapolationIcon;
+        }
+
+        Rect GetPreExtrapolationBounds(Rect trackRect, Rect clipRect, GUIStyle icon)
+        {
+            float x = clipRect.xMin - (icon.fixedWidth + 10.0f);
+            float y = trackRect.yMin + (trackRect.height - icon.fixedHeight) / 2.0f;
+
+            if (previousClip != null)
+            {
+                float distance = Mathf.Abs(treeViewRect.xMin - previousClip.treeViewRect.xMax);
+
+                if (distance < icon.fixedWidth)
+                    return new Rect(0.0f, 0.0f, 0.0f, 0.0f);
+
+                if (distance < icon.fixedWidth + 20.0f)
+                {
+                    float delta = (distance - icon.fixedWidth) / 2.0f;
+                    x = clipRect.xMin - (icon.fixedWidth + delta);
+                }
+            }
+
+            return new Rect(x, y, icon.fixedWidth, icon.fixedHeight);
+        }
+
+        Rect GetPostExtrapolationBounds(Rect trackRect, Rect clipRect, GUIStyle icon)
+        {
+            float x = clipRect.xMax + 10.0f;
+            float y = trackRect.yMin + (trackRect.height - icon.fixedHeight) / 2.0f;
+
+            if (nextClip != null)
+            {
+                float distance = Mathf.Abs(nextClip.treeViewRect.xMin - treeViewRect.xMax);
+
+                if (distance < icon.fixedWidth)
+                    return new Rect(0.0f, 0.0f, 0.0f, 0.0f);
+
+                if (distance < icon.fixedWidth + 20.0f)
+                {
+                    float delta = (distance - icon.fixedWidth) / 2.0f;
+                    x = clipRect.xMax + delta;
+                }
+            }
+
+            return new Rect(x, y, icon.fixedWidth, icon.fixedHeight);
+        }
+
+        static void DrawExtrapolationIcon(Rect rect, GUIStyle icon)
+        {
+            GUI.Label(rect, GUIContent.none, icon);
+        }
+
+        void DrawExtrapolation(Rect trackRect, Rect clipRect)
+        {
+            if (clip.hasPreExtrapolation)
+            {
+                GUIStyle icon = GetExtrapolationIcon(clip.preExtrapolationMode);
+
+                if (icon != null)
+                {
+                    Rect iconBounds = GetPreExtrapolationBounds(trackRect, clipRect, icon);
+
+                    if (iconBounds.width > 1 && iconBounds.height > 1)
+                        DrawExtrapolationIcon(iconBounds, icon);
+                }
+            }
+
+            if (clip.hasPostExtrapolation)
+            {
+                GUIStyle icon = GetExtrapolationIcon(clip.postExtrapolationMode);
+
+                if (icon != null)
+                {
+                    Rect iconBounds = GetPostExtrapolationBounds(trackRect, clipRect, icon);
+
+                    if (iconBounds.width > 1 && iconBounds.height > 1)
+                        DrawExtrapolationIcon(iconBounds, icon);
+                }
+            }
+        }
+
+        static Rect ProjectRectOnTimeline(Rect rect, Rect trackRect, WindowState state)
+        {
+            Rect newRect = rect;
+            // transform clipRect into pixel-space
+            newRect.x *= state.timeAreaScale.x;
+            newRect.width *= state.timeAreaScale.x;
+
+            newRect.x += state.timeAreaTranslation.x + trackRect.xMin;
+
+            // adjust clipRect height and vertical centering
+            const int clipPadding = 2;
+            newRect.y = trackRect.y + clipPadding;
+            newRect.height = trackRect.height - (2 * clipPadding);
+            return newRect;
+        }
+
+        void CalculateLoopRects(Rect trackRect, WindowState state)
+        {
+            if (!m_ClipViewDirty)
+                return;
+
+            m_LoopRects.Clear();
+            if (clip.duration < WindowState.kTimeEpsilon)
+                return;
+
+            var times = TimelineHelpers.GetLoopTimes(clip);
+            var loopDuration = TimelineHelpers.GetLoopDuration(clip);
+            m_MinLoopIndex = -1;
+
+            // we have a hold, no need to compute all loops
+            if (!supportsLooping)
+            {
+                if (times.Length > 1)
+                {
+                    var t = times[1];
+                    float loopTime = (float)(clip.duration - t);
+                    m_LoopRects.Add(ProjectRectOnTimeline(new Rect((float)(t + clip.start), 0, loopTime, 0), trackRect, state));
+                }
+                return;
+            }
+
+            var range = state.timeAreaShownRange;
+            var visibleStartTime = range.x - clip.start;
+            var visibleEndTime = range.y - clip.start;
+
+            for (int i = 1; i < times.Length; i++)
+            {
+                var t = times[i];
+
+                // don't draw off screen loops
+                if (t > visibleEndTime)
+                    break;
+
+                float loopTime = Mathf.Min((float)(clip.duration - t), (float)loopDuration);
+                var loopEnd = t + loopTime;
+
+                if (loopEnd < visibleStartTime)
+                    continue;
+
+                m_LoopRects.Add(ProjectRectOnTimeline(new Rect((float)(t + clip.start), 0, loopTime, 0), trackRect, state));
+
+                if (m_MinLoopIndex == -1)
+                    m_MinLoopIndex = i;
+            }
+        }
+
+        public override Rect RectToTimeline(Rect trackRect, WindowState state)
+        {
+            var offsetFromTimeSpaceToPixelSpace = state.timeAreaTranslation.x + trackRect.xMin;
+
+            var start = (float)(DiscreteTime)clip.start;
+            var end = (float)(DiscreteTime)clip.end;
+
+            return Rect.MinMaxRect(
+                Mathf.Round(start * state.timeAreaScale.x + offsetFromTimeSpaceToPixelSpace), Mathf.Round(trackRect.yMin),
+                Mathf.Round(end * state.timeAreaScale.x + offsetFromTimeSpaceToPixelSpace), Mathf.Round(trackRect.yMax)
+            );
+        }
+
+        public IEnumerable<Edge> SnappableEdgesFor(IAttractable attractable, ManipulateEdges manipulateEdges)
+        {
+            var edges = new List<Edge>();
+
+            bool canAddEdges = !parent.muted;
+
+            if (canAddEdges)
+            {
+                // Hack: Trim Start in Ripple mode should not have any snap point added
+                if (EditMode.editType == EditMode.EditType.Ripple && manipulateEdges == ManipulateEdges.Left)
+                    return edges;
+
+                if (attractable != this)
+                {
+                    if (EditMode.editType == EditMode.EditType.Ripple)
+                    {
+                        bool skip = false;
+
+                        // Hack: Since Trim End and Move in Ripple mode causes other snap point to move on the same track (which is not supported), disable snapping for this special cases...
+                        // TODO Find a proper way to have different snap edges for each edit mode.
+                        if (manipulateEdges == ManipulateEdges.Right)
+                        {
+                            var otherClipGUI = attractable as TimelineClipGUI;
+                            skip = otherClipGUI != null && otherClipGUI.parent == parent;
+                        }
+                        else if (manipulateEdges == ManipulateEdges.Both)
+                        {
+                            var moveHandler = attractable as MoveItemHandler;
+                            skip = moveHandler != null && moveHandler.movingItems.Any(clips => clips.targetTrack == clip.parentTrack && clip.start >= clips.start);
+                        }
+
+                        if (skip)
+                            return edges;
+                    }
+
+                    AddEdge(edges, clip.start);
+                    AddEdge(edges, clip.end);
+                }
+                else
+                {
+                    if (manipulateEdges == ManipulateEdges.Right)
+                    {
+                        var d = TimelineHelpers.GetClipAssetEndTime(clip);
+
+                        if (d < double.MaxValue)
+                        {
+                            if (clip.SupportsLooping())
+                            {
+                                var l = TimelineHelpers.GetLoopDuration(clip);
+
+                                var shownTime = TimelineWindow.instance.state.timeAreaShownRange;
+                                do
+                                {
+                                    AddEdge(edges, d, false);
+                                    d += l;
+                                }
+                                while (d < shownTime.y);
+                            }
+                            else
+                            {
+                                AddEdge(edges, d, false);
+                            }
+                        }
+                    }
+
+                    if (manipulateEdges == ManipulateEdges.Left)
+                    {
+                        var clipInfo = AnimationClipCurveCache.Instance.GetCurveInfo(clip.animationClip);
+                        if (clipInfo != null && clipInfo.keyTimes.Any())
+                            AddEdge(edges, clip.FromLocalTimeUnbound(clipInfo.keyTimes.Min()), false);
+                    }
+                }
+            }
+            return edges;
+        }
+
+        public bool ShouldSnapTo(ISnappable snappable)
+        {
+            return true;
+        }
+
+        bool ShowDrillIcon(PlayableDirector resolver)
+        {
+            if (!m_ShowDrillIcon.HasValue || TimelineWindow.instance.hierarchyChangedThisFrame)
+            {
+                var nestable = m_ClipEditor.supportsSubTimelines;
+                m_ShowDrillIcon = nestable && resolver != null;
+                if (m_ShowDrillIcon.Value)
+                {
+                    s_TempSubDirectors.Clear();
+                    try
+                    {
+                        m_ClipEditor.GetSubTimelines(clip, resolver, s_TempSubDirectors);
+                    }
+                    catch (Exception e)
+                    {
+                        Debug.LogException(e);
+                    }
+
+                    m_ShowDrillIcon &= s_TempSubDirectors.Count > 0;
+                }
+            }
+
+            return m_ShowDrillIcon.Value;
+        }
+
+        static void AddEdge(List<Edge> edges, double time, bool showEdgeHint = true)
+        {
+            var shownTime = TimelineWindow.instance.state.timeAreaShownRange;
+            if (time >= shownTime.x && time <= shownTime.y)
+                edges.Add(new Edge(time, showEdgeHint));
+        }
+    }
+}
diff --git a/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineClipGUI.cs.meta b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineClipGUI.cs.meta
new file mode 100644
index 0000000..4e94156
--- /dev/null
+++ b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineClipGUI.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 3c01b61b3a6887c49a15276fd38be918
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
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+  assetBundleVariant: 
diff --git a/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineItemGUI.cs b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineItemGUI.cs
new file mode 100644
index 0000000..522b35e
--- /dev/null
+++ b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineItemGUI.cs
@@ -0,0 +1,92 @@
+using System;
+using System.Collections.Generic;
+using UnityEngine.Timeline;
+using UnityEngine;
+
+namespace UnityEditor.Timeline
+{
+    static class ItemToItemGui
+    {
+        static Dictionary<object, TimelineItemGUI> s_ItemToItemGUI =
+            new Dictionary<object, TimelineItemGUI>();
+
+        public static void Add(TimelineClip clip, TimelineItemGUI gui)
+        {
+            s_ItemToItemGUI[clip] = gui;
+        }
+
+        public static void Add(IMarker marker, TimelineItemGUI gui)
+        {
+            s_ItemToItemGUI[marker] = gui;
+        }
+
+        public static TimelineClipGUI GetGuiForClip(TimelineClip clip)
+        {
+            return GetGuiForItem(clip) as TimelineClipGUI;
+        }
+
+        public static TimelineMarkerGUI GetGuiForMarker(IMarker marker)
+        {
+            return GetGuiForItem(marker) as TimelineMarkerGUI;
+        }
+
+        static TimelineItemGUI GetGuiForItem(object item)
+        {
+            if (item == null)
+                return null;
+
+            TimelineItemGUI gui;
+            s_ItemToItemGUI.TryGetValue(item, out gui);
+            return gui;
+        }
+    }
+
+    abstract class TimelineItemGUI : ISelectable
+    {
+        protected readonly DirectorStyles m_Styles;
+
+        public abstract ITimelineItem item { get; }
+        public abstract double start { get; }
+        public abstract double end { get; }
+        public abstract void Draw(Rect rect, bool rectChanged, WindowState state);
+        public abstract Rect RectToTimeline(Rect trackRect, WindowState state);
+
+        public virtual void Select() {}
+        public virtual bool IsSelected() { return false; }
+        public virtual void Deselect() {}
+
+        public virtual void StartDrag() {}
+        public virtual void StopDrag() {}
+
+        public LayerZOrder zOrder { get; set; }
+
+        public bool visible { get; set; }
+        public bool isInvalid { get; set; }
+
+        public IRowGUI parent { get; }
+
+        public Rect rect
+        {
+            get { return parent.ToWindowSpace(treeViewRect); }
+        }
+
+        public Rect treeViewRect
+        {
+            get { return m_TreeViewRect; }
+            protected set
+            {
+                m_TreeViewRect = value;
+                if (value.width < 0.0f)
+                    m_TreeViewRect.width = 1.0f;
+            }
+        }
+
+        Rect m_TreeViewRect;
+
+        protected TimelineItemGUI(IRowGUI parent)
+        {
+            this.parent = parent;
+            m_Styles = DirectorStyles.Instance;
+        }
+    }
+}
diff --git a/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineItemGUI.cs.meta b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineItemGUI.cs.meta
new file mode 100644
index 0000000..a38143d
--- /dev/null
+++ b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineItemGUI.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 6f515f8ecd3b6a546b90abaae2553f99
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
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diff --git a/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerClusterGUI.cs b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerClusterGUI.cs
new file mode 100644
index 0000000..b0ffeac
--- /dev/null
+++ b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerClusterGUI.cs
@@ -0,0 +1,150 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using UnityEngine;
+
+using UnityObject = UnityEngine.Object;
+
+namespace UnityEditor.Timeline
+{
+    class TimelineMarkerClusterGUI : TimelineItemGUI
+    {
+        readonly List<TimelineMarkerGUI> m_MarkerGUIs;
+        readonly IZOrderProvider m_ZOrderProvider;
+
+        public TimelineMarkerGUI topMarker
+        {
+            get { return m_MarkerGUIs.LastOrDefault(); }
+        }
+
+        TimelineMarkerGUI m_ManipulatedMarker;
+
+        public TimelineMarkerClusterGUI(List<TimelineMarkerGUI> guis, IRowGUI parent,
+                                        IZOrderProvider zOrderProvider, LayerZOrder layerZOrder)
+            : base(parent)
+        {
+            m_MarkerGUIs = guis;
+            m_ZOrderProvider = zOrderProvider;
+            zOrder = layerZOrder;
+            SortMarkers();
+            topMarker.onStartDrag += OnDragTopMarker;
+        }
+
+        public override double start
+        {
+            get { return topMarker.start; }
+        }
+
+        public override double end
+        {
+            get { return topMarker.end; }
+        }
+
+        public override ITimelineItem item
+        {
+            get { return topMarker.item; }
+        }
+
+        public override void Select()
+        {
+            foreach (var marker in m_MarkerGUIs)
+            {
+                if (!marker.IsSelected())
+                    marker.Select();
+            }
+        }
+
+        public override void Deselect()
+        {
+            foreach (var marker in m_MarkerGUIs)
+            {
+                if (marker.IsSelected())
+                    marker.Deselect();
+            }
+        }
+
+        public override void Draw(Rect trackRect, bool trackRectChanged, WindowState state)
+        {
+            RegisterRect(state);
+
+            topMarker.Draw(trackRect, trackRectChanged, state);
+
+            if (m_MarkerGUIs.Count > 1)
+                GUI.Box(treeViewRect, String.Empty, DirectorStyles.Instance.markerMultiOverlay);
+
+            if (m_ManipulatedMarker != null)
+                m_ManipulatedMarker.Draw(trackRect, trackRectChanged, state);
+        }
+
+        public override Rect RectToTimeline(Rect trackRect, WindowState state)
+        {
+            return topMarker.RectToTimeline(trackRect, state);
+        }
+
+        public void CycleTop()
+        {
+            if (m_MarkerGUIs.Count < 2)
+                return;
+
+            topMarker.onStartDrag -= OnDragTopMarker;
+
+            var last = topMarker;
+            for (int i = 0; i < m_MarkerGUIs.Count; ++i)
+            {
+                var next = m_MarkerGUIs[i];
+                m_MarkerGUIs[i] = last;
+                last = next;
+            }
+
+            topMarker.zOrder = m_ZOrderProvider.Next();
+
+            topMarker.onStartDrag += OnDragTopMarker;
+        }
+
+        void OnDragTopMarker()
+        {
+            m_ManipulatedMarker = topMarker;
+            m_ManipulatedMarker.onStartDrag -= OnDragTopMarker;
+            m_MarkerGUIs.RemoveAt(m_MarkerGUIs.Count - 1);
+        }
+
+        void SortMarkers()
+        {
+            m_MarkerGUIs.Sort((lhs, rhs) => lhs.zOrder.CompareTo(rhs.zOrder));
+        }
+
+        void RegisterRect(WindowState state)
+        {
+            treeViewRect = topMarker.treeViewRect;
+
+            if (Event.current.type == EventType.Repaint && !parent.locked)
+                state.spacePartitioner.AddBounds(this, rect);
+        }
+
+        public static bool CanCycleMarkers()
+        {
+            if (!SelectionManager.SelectedMarkers().Any())
+                return false;
+
+            var cluster = PickerUtils.PickedLayerableOfType<TimelineMarkerClusterGUI>();
+
+            if (cluster == null)
+                return false;
+
+            // Only cycle if the marker is selected and nothing else is selected
+            return cluster.topMarker.IsSelected() && SelectionManager.Count() == 1;
+        }
+
+        public static void CycleMarkers()
+        {
+            var cluster = PickerUtils.PickedLayerableOfType<TimelineMarkerClusterGUI>();
+
+            if (cluster == null)
+                return;
+
+            cluster.topMarker.Deselect();
+            cluster.CycleTop();
+            cluster.topMarker.Select();
+        }
+    }
+}
diff --git a/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerClusterGUI.cs.meta b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerClusterGUI.cs.meta
new file mode 100644
index 0000000..692661f
--- /dev/null
+++ b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerClusterGUI.cs.meta
@@ -0,0 +1,11 @@
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+guid: 2c03ae9aa36a4fd44a983831f44654be
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerGUI.cs b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerGUI.cs
new file mode 100644
index 0000000..5f054f7
--- /dev/null
+++ b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerGUI.cs
@@ -0,0 +1,193 @@
+using System;
+using System.Collections.Generic;
+using UnityEngine;
+using UnityEngine.Timeline;
+using UnityObject = UnityEngine.Object;
+
+namespace UnityEditor.Timeline
+{
+    class TimelineMarkerGUI : TimelineItemGUI, ISnappable, IAttractable
+    {
+        public event Action onStartDrag;
+
+        int m_ProjectedClipHash;
+        int m_MarkerHash;
+        bool m_Selectable;
+
+        MarkerDrawOptions m_MarkerDrawOptions;
+        MarkerEditor m_Editor;
+
+        IMarker marker { get; }
+
+        bool selectable
+        {
+            get { return m_Selectable; }
+        }
+
+        public double time
+        {
+            get { return marker.time; }
+        }
+
+        public override double start
+        {
+            get { return time; }
+        }
+
+        public override double end
+        {
+            get { return time; }
+        }
+
+        public override void Select()
+        {
+            zOrder = zOrderProvider.Next();
+            SelectionManager.Add(marker);
+            TimelineWindowViewPrefs.GetTrackViewModelData(parent.asset).markerTimeStamps[m_MarkerHash] = DateTime.UtcNow.Ticks;
+        }
+
+        public override bool IsSelected()
+        {
+            return SelectionManager.Contains(marker);
+        }
+
+        public override void Deselect()
+        {
+            SelectionManager.Remove(marker);
+        }
+
+        public override ITimelineItem item
+        {
+            get { return ItemsUtils.ToItem(marker); }
+        }
+
+        IZOrderProvider zOrderProvider { get; }
+
+        public TimelineMarkerGUI(IMarker theMarker, IRowGUI parent, IZOrderProvider provider) : base(parent)
+        {
+            marker = theMarker;
+            m_Selectable = marker.GetType().IsSubclassOf(typeof(UnityObject));
+
+            m_MarkerHash = 0;
+            var o = marker as object;
+            if (!o.Equals(null))
+                m_MarkerHash = o.GetHashCode();
+
+            zOrderProvider = provider;
+            zOrder = zOrderProvider.Next();
+            ItemToItemGui.Add(marker, this);
+            m_Editor = CustomTimelineEditorCache.GetMarkerEditor(theMarker);
+        }
+
+        int ComputeDirtyHash()
+        {
+            return time.GetHashCode();
+        }
+
+        static void DrawMarker(Rect drawRect, Type type, bool isSelected, bool isCollapsed, MarkerDrawOptions options)
+        {
+            if (Event.current.type == EventType.Repaint)
+            {
+                bool hasError = !string.IsNullOrEmpty(options.errorText);
+
+                var style = StyleManager.UssStyleForType(type);
+                style.Draw(drawRect, GUIContent.none, false, false, !isCollapsed, isSelected);
+
+                // case1141836: Use of GUI.Box instead of GUI.Label causes desync in UI controlID
+                if (hasError)
+                    GUI.Label(drawRect, String.Empty, DirectorStyles.Instance.markerWarning);
+
+                var tooltip = hasError ? options.errorText : options.tooltip;
+                if (!string.IsNullOrEmpty(tooltip) && drawRect.Contains(Event.current.mousePosition))
+                {
+                    GUIStyle.SetMouseTooltip(tooltip, drawRect);
+                }
+            }
+        }
+
+        void UpdateDrawData()
+        {
+            if (Event.current.type == EventType.Layout)
+            {
+                try
+                {
+                    m_MarkerDrawOptions = m_Editor.GetMarkerOptions(marker);
+                }
+                catch (Exception e)
+                {
+                    Debug.LogException(e);
+                    m_MarkerDrawOptions = CustomTimelineEditorCache.GetDefaultMarkerEditor().GetMarkerOptions(marker);
+                }
+            }
+        }
+
+        public override void Draw(Rect trackRect, bool trackRectChanged, WindowState state)
+        {
+            UpdateDrawData();
+
+            // compute marker hash
+            var currentMarkerHash = ComputeDirtyHash();
+
+            // update the clip projected rectangle on the timeline
+            CalculateClipRectangle(trackRect, state, currentMarkerHash, trackRectChanged);
+
+            var isSelected = selectable && SelectionManager.Contains(marker);
+            var showMarkers = parent.showMarkers;
+
+            QueueOverlay(treeViewRect, isSelected, !showMarkers);
+            DrawMarker(treeViewRect, marker.GetType(), isSelected, !showMarkers, m_MarkerDrawOptions);
+
+            if (Event.current.type == EventType.Repaint && showMarkers && !parent.locked)
+                state.spacePartitioner.AddBounds(this, rect);
+        }
+
+        public void QueueOverlay(Rect rect, bool isSelected, bool isCollapsed)
+        {
+            if (Event.current.type == EventType.Repaint && m_Editor.supportsDrawOverlay)
+            {
+                rect = GUIClip.Unclip(rect);
+                TimelineWindow.instance.AddUserOverlay(marker, rect, m_Editor, isCollapsed, isSelected);
+            }
+        }
+
+        public override void StartDrag()
+        {
+            if (onStartDrag != null)
+                onStartDrag.Invoke();
+        }
+
+        void CalculateClipRectangle(Rect trackRect, WindowState state, int projectedClipHash, bool trackRectChanged)
+        {
+            if (m_ProjectedClipHash == projectedClipHash && !trackRectChanged)
+                return;
+
+            m_ProjectedClipHash = projectedClipHash;
+            treeViewRect = RectToTimeline(trackRect, state);
+        }
+
+        public override Rect RectToTimeline(Rect trackRect, WindowState state)
+        {
+            var style = StyleManager.UssStyleForType(marker.GetType());
+            var width = style.fixedWidth;
+            var height = style.fixedHeight;
+            var x = ((float)marker.time * state.timeAreaScale.x) + state.timeAreaTranslation.x + trackRect.xMin;
+            x -= 0.5f * width;
+            return new Rect(x, trackRect.y, width, height);
+        }
+
+        public IEnumerable<Edge> SnappableEdgesFor(IAttractable attractable, ManipulateEdges manipulateEdges)
+        {
+            var edges = new List<Edge>();
+            var attractableGUI = attractable as TimelineMarkerGUI;
+            var canAddEdges = !(attractableGUI != null && attractableGUI.parent == parent);
+            if (canAddEdges)
+                edges.Add(new Edge(time));
+            return edges;
+        }
+
+        public bool ShouldSnapTo(ISnappable snappable)
+        {
+            return snappable != this;
+        }
+    }
+}
diff --git a/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerGUI.cs.meta b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerGUI.cs.meta
new file mode 100644
index 0000000..ecfff45
--- /dev/null
+++ b/Library/PackageCache/com.unity.timeline@1.2.13/Editor/treeview/ItemGui/TimelineMarkerGUI.cs.meta
@@ -0,0 +1,11 @@
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