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Source/Editor/Content/Proxy/ParticleSystemProxy.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="ParticleSystem"/> asset proxy object.
+    /// </summary>
+    /// <seealso cref="FlaxEditor.Content.BinaryAssetProxy" />
+    public class ParticleSystemProxy : BinaryAssetProxy
+    {
+        private ParticleSystemPreview _preview;
+        private ThumbnailRequest _warmupRequest;
+
+        /// <inheritdoc />
+        public override string Name => "Particle System";
+
+        /// <inheritdoc />
+        public override EditorWindow Open(Editor editor, ContentItem item)
+        {
+            return new ParticleSystemWindow(editor, item as AssetItem);
+        }
+
+        /// <inheritdoc />
+        public override Color AccentColor => Color.FromRGB(0xFF790200);
+
+        /// <inheritdoc />
+        public override Type AssetType => typeof(ParticleSystem);
+
+        /// <inheritdoc />
+        public override bool CanCreate(ContentFolder targetLocation)
+        {
+            return targetLocation.CanHaveAssets;
+        }
+
+        /// <inheritdoc />
+        public override void Create(string outputPath, object arg)
+        {
+            if (Editor.CreateAsset(Editor.NewAssetType.ParticleSystem, outputPath))
+                throw new Exception("Failed to create new asset.");
+        }
+
+        /// <inheritdoc />
+        public override void OnThumbnailDrawPrepare(ThumbnailRequest request)
+        {
+            if (_preview == null)
+            {
+                _preview = new ParticleEmitterPreview(false)
+                {
+                    RenderOnlyWithWindow = false,
+                    AnchorPreset = AnchorPresets.StretchAll,
+                    Offsets = Margin.Zero,
+                };
+                _preview.Task.Enabled = false;
+
+                var eyeAdaptation = _preview.PostFxVolume.EyeAdaptation;
+                eyeAdaptation.Mode = EyeAdaptationMode.None;
+                eyeAdaptation.OverrideFlags |= EyeAdaptationSettingsOverride.Mode;
+                _preview.PostFxVolume.EyeAdaptation = eyeAdaptation;
+            }
+
+            // Mark for initial warmup
+            request.Tag = 0;
+        }
+
+        /// <inheritdoc />
+        public override bool CanDrawThumbnail(ThumbnailRequest request)
+        {
+            var state = (int)request.Tag;
+            if (state == 2)
+                return true;
+
+            // Allow only one request at once during warmup time
+            if (_warmupRequest != null && _warmupRequest != request)
+                return false;
+
+            // Ensure assets are ready to be used
+            if (!_preview.HasLoadedAssets)
+                return false;
+            var asset = (ParticleSystem)request.Asset;
+            if (!asset.IsLoaded)
+                return false;
+
+            if (state == 0)
+            {
+                // Start the warmup
+                _warmupRequest = request;
+                request.Tag = 1;
+                _preview.System = asset;
+            }
+            else if (_preview.PreviewActor.Time >= Mathf.Min(0.2f * asset.Duration, 0.6f))
+            {
+                // End the warmup
+                request.Tag = 2;
+                _preview.FitIntoView();
+                return true;
+            }
+
+            // Handle warmup time for the preview
+            _preview.PreviewActor.UpdateSimulation();
+            return false;
+        }
+
+        /// <inheritdoc />
+        public override void OnThumbnailDrawBegin(ThumbnailRequest request, ContainerControl guiRoot, GPUContext context)
+        {
+            _preview.Parent = guiRoot;
+            _preview.SyncBackbufferSize();
+
+            _preview.Task.OnDraw();
+        }
+
+        /// <inheritdoc />
+        public override void OnThumbnailDrawEnd(ThumbnailRequest request, ContainerControl guiRoot)
+        {
+            if (_warmupRequest == request)
+            {
+                _warmupRequest = null;
+            }
+
+            _preview.System = null;
+            _preview.Parent = null;
+        }
+
+        /// <inheritdoc />
+        public override void OnThumbnailDrawCleanup(ThumbnailRequest request)
+        {
+            if (_warmupRequest == request)
+            {
+                _warmupRequest = null;
+            }
+        }
+
+        /// <inheritdoc />
+        public override void Dispose()
+        {
+            if (_preview != null)
+            {
+                _preview.Dispose();
+                _preview = null;
+            }
+
+            base.Dispose();
+        }
+    }
+}