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Source/Editor/GUI/Timeline/Tracks/NestedSceneAnimationTrack.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+using System;
+using System.IO;
+using FlaxEngine;
+
+namespace FlaxEditor.GUI.Timeline.Tracks
+{
+    /// <summary>
+    /// The timeline media that represents a nested scene animation media event.
+    /// </summary>
+    /// <seealso cref="FlaxEditor.GUI.Timeline.Media" />
+    public class NestedSceneAnimationMedia : SingleMediaAssetMedia
+    {
+        private sealed class Proxy : ProxyBase<NestedSceneAnimationTrack, NestedSceneAnimationMedia>
+        {
+            /// <summary>
+            /// Gets or sets the nested scene animation to play.
+            /// </summary>
+            [EditorDisplay("General"), EditorOrder(10), Tooltip("The nested scene animation to play.")]
+            public SceneAnimation NestedSceneAnimation
+            {
+                get => Track.Asset;
+                set => Track.Asset = value;
+            }
+
+            /// <summary>
+            /// Gets or sets the nested animation looping mode.
+            /// </summary>
+            [EditorDisplay("General"), EditorOrder(20), Tooltip("If checked, the nested animation will loop when playback exceeds its duration. Otherwise it will stop play.")]
+            public bool Loop
+            {
+                get => Track.Loop;
+                set => Track.Loop = value;
+            }
+
+            /// <inheritdoc />
+            public Proxy(NestedSceneAnimationTrack track, NestedSceneAnimationMedia media)
+            : base(track, media)
+            {
+            }
+        }
+
+        /// <inheritdoc />
+        public override void OnTimelineChanged(Track track)
+        {
+            base.OnTimelineChanged(track);
+
+            PropertiesEditObject = new Proxy(Track as NestedSceneAnimationTrack, this);
+        }
+    }
+
+    /// <summary>
+    /// The timeline track that represents a nested scene animation playback.
+    /// </summary>
+    /// <seealso cref="FlaxEditor.GUI.Timeline.Track" />
+    public class NestedSceneAnimationTrack : SingleMediaAssetTrack<SceneAnimation, NestedSceneAnimationMedia>
+    {
+        /// <summary>
+        /// Gets the archetype.
+        /// </summary>
+        /// <returns>The archetype.</returns>
+        public static TrackArchetype GetArchetype()
+        {
+            return new TrackArchetype
+            {
+                TypeId = 3,
+                Name = "Nested Timeline",
+                Create = options => new NestedSceneAnimationTrack(ref options),
+                Load = LoadTrack,
+                Save = SaveTrack,
+            };
+        }
+
+        private static void LoadTrack(int version, Track track, BinaryReader stream)
+        {
+            var e = (NestedSceneAnimationTrack)track;
+            Guid id = new Guid(stream.ReadBytes(16));
+            e.Asset = FlaxEngine.Content.LoadAsync<SceneAnimation>(id);
+            var m = e.TrackMedia;
+            m.StartFrame = stream.ReadInt32();
+            m.DurationFrames = stream.ReadInt32();
+        }
+
+        private static void SaveTrack(Track track, BinaryWriter stream)
+        {
+            var e = (NestedSceneAnimationTrack)track;
+            var assetId = e.Asset?.ID ?? Guid.Empty;
+
+            stream.Write(assetId.ToByteArray());
+
+            if (e.Media.Count != 0)
+            {
+                var m = e.TrackMedia;
+                stream.Write(m.StartFrame);
+                stream.Write(m.DurationFrames);
+            }
+            else
+            {
+                stream.Write(0);
+                stream.Write(track.Timeline.DurationFrames);
+            }
+        }
+
+        /// <summary>
+        /// Gets or sets the nested animation looping mode.
+        /// </summary>
+        public bool TrackLoop
+        {
+            get => Loop;
+            set
+            {
+                if (Loop == value)
+                    return;
+                Loop = value;
+                Timeline?.MarkAsEdited();
+            }
+        }
+
+        /// <inheritdoc />
+        public NestedSceneAnimationTrack(ref TrackCreateOptions options)
+        : base(ref options)
+        {
+        }
+    }
+}