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Source/Editor/Content/Proxy/SpriteAtlasProxy.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+using System;
+using FlaxEditor.Content.Thumbnails;
+using FlaxEditor.Viewport.Previews;
+using FlaxEditor.Windows;
+using FlaxEditor.Windows.Assets;
+using FlaxEngine;
+using FlaxEngine.GUI;
+
+namespace FlaxEditor.Content
+{
+    /// <summary>
+    /// A <see cref="SpriteAtlas"/> asset proxy object.
+    /// </summary>
+    /// <seealso cref="FlaxEditor.Content.BinaryAssetProxy" />
+    public sealed class SpriteAtlasProxy : BinaryAssetProxy
+    {
+        private SimpleSpriteAtlasPreview _preview;
+
+        /// <inheritdoc />
+        public override string Name => "Sprite Atlas";
+
+        /// <inheritdoc />
+        public override bool CanReimport(ContentItem item)
+        {
+            return true;
+        }
+
+        /// <inheritdoc />
+        public override EditorWindow Open(Editor editor, ContentItem item)
+        {
+            return new SpriteAtlasWindow(editor, (AssetItem)item);
+        }
+
+        /// <inheritdoc />
+        public override Color AccentColor => Color.FromRGB(0x5C7F69);
+
+        /// <inheritdoc />
+        public override Type AssetType => typeof(SpriteAtlas);
+
+        /// <inheritdoc />
+        public override void OnThumbnailDrawPrepare(ThumbnailRequest request)
+        {
+            if (_preview == null)
+            {
+                _preview = new SimpleSpriteAtlasPreview
+                {
+                    AnchorPreset = AnchorPresets.StretchAll,
+                    Offsets = Margin.Zero,
+                };
+            }
+
+            // TODO: disable streaming for asset during thumbnail rendering (and restore it after)
+        }
+
+        /// <inheritdoc />
+        public override bool CanDrawThumbnail(ThumbnailRequest request)
+        {
+            // Check if asset is streamed enough
+            var asset = (SpriteAtlas)request.Asset;
+            return asset.ResidentMipLevels >= Mathf.Max(1, (int)(asset.MipLevels * ThumbnailsModule.MinimumRequiredResourcesQuality));
+        }
+
+        /// <inheritdoc />
+        public override void OnThumbnailDrawBegin(ThumbnailRequest request, ContainerControl guiRoot, GPUContext context)
+        {
+            _preview.Asset = (SpriteAtlas)request.Asset;
+            _preview.Parent = guiRoot;
+        }
+
+        /// <inheritdoc />
+        public override void OnThumbnailDrawEnd(ThumbnailRequest request, ContainerControl guiRoot)
+        {
+            _preview.Asset = null;
+            _preview.Parent = null;
+        }
+
+        /// <inheritdoc />
+        public override void Dispose()
+        {
+            if (_preview != null)
+            {
+                _preview.Dispose();
+                _preview = null;
+            }
+
+            base.Dispose();
+        }
+    }
+}