Handle loading error and placeholder shaders

GlitchyEditor/src/EditWindows/ContentBrowserWindow.bf

@@ -316,8 +316,7 @@ namespace GlitchyEditor.EditWindows
 		{
 			_manager.Update();
 
-			// Show History
-			if (ImGui.Begin("Debug History"))
+			/*if (ImGui.Begin("Debug History"))
 			{
 				ImGui.CollapsingHeader("History");
 				for (String path in _directoryHistory.[Friend]_history)
@@ -338,7 +337,7 @@ namespace GlitchyEditor.EditWindows
 				}
 
 				ImGui.End();
-			}
+			}*/
 			
 			// Make sure we are in an existing directory.
 			if (!_manager.AssetHierarchy.FileExists(CurrentDirectory))
@@ -745,57 +744,81 @@ namespace GlitchyEditor.EditWindows
 
 		private ImGui.RectangleSelectionData _rectangleSelection;
 
+		enum Modifiers
+		{
+			None,
+			Alt,
+			Ctrl,
+			Shift
+		}
+
+		private void HandleShortcuts()
+		{
+			Modifiers modifiers = .None;
+
+			Enum.SetFlagConditionally(ref modifiers, .Alt, Input.IsKeyPressed(.Alt));
+			Enum.SetFlagConditionally(ref modifiers, .Ctrl, Input.IsKeyPressed(.Control));
+			Enum.SetFlagConditionally(ref modifiers, .Shift, Input.IsKeyPressed(.Shift));
+
+			// TODO: Come up with a good hotkey system...
+			if (modifiers == .Alt)
+			{
+				if (Input.IsKeyPressing(.Up))
+				{
+					NavigateUp();
+				}
+
+				if (Input.IsKeyPressing(.Left))
+				{
+					NavigateBack();
+				}
+
+				if (Input .IsKeyPressing(.Right))
+				{
+					NavigateForward();
+				}
+			}
+
+			if (Input.IsMouseButtonPressing(.XButton1))
+			{
+				NavigateBack();
+			}
+
+			if (Input.IsMouseButtonPressing(.XButton2))
+			{
+				NavigateForward();
+			}
+
+			if (modifiers == .Ctrl)
+			{
+				if (Input.IsKeyPressing(.C))
+				{
+					CopySelectedFiles(cutFiles: false);
+				}
+				
+				if (Input.IsKeyPressing(.X))
+				{
+					CopySelectedFiles(cutFiles: true);
+				}
+
+				if (Input.IsKeyPressing(.V))
+				{
+					PasteFiles(CurrentDirectory);
+				}
+			}
+
+			if (modifiers == .Ctrl | .Shift)
+			{
+
+			}
+		}
+
 		/// Renders the contents of _currentDirectory. Returns the node of the current directory, or null if the browser isn't in a directory.
 		private void DrawCurrentDirectory(TreeNode<AssetNode> currentDirectoryNode)
 		{
 			if (ImGui.IsWindowHovered())
 			{
-				// TODO: Come up with a good hotkey system...
-				if (Input.IsKeyPressed(.Alt))
-				{
-					if (Input.IsKeyPressing(.Up))
-					{
-						NavigateUp();
-					}
-
-					if (Input.IsKeyPressing(.Left))
-					{
-						NavigateBack();
-					}
-
-					if (Input .IsKeyPressing(.Right))
-					{
-						NavigateForward();
-					}
-				}
-
-				if (Input.IsMouseButtonPressing(.XButton1))
-				{
-					NavigateBack();
-				}
-
-				if (Input.IsMouseButtonPressing(.XButton2))
-				{
-					NavigateForward();
-				}
-
-				if (Input.IsKeyPressed(.Control))
-				{
-					if (Input.IsKeyPressing(.C))
-					{
-						CopySelectedFiles(cutFiles: false);
-					}
-					
-					if (Input.IsKeyPressing(.X))
-					{
-						CopySelectedFiles(cutFiles: true);
-					}
-
-					if (Input.IsKeyPressing(.V))
-					{
-						PasteFiles(CurrentDirectory);
-					}
-				}
+				HandleShortcuts();
 			}
 
 			List<TreeNode<AssetNode>> directoryEntries = scope List<TreeNode<AssetNode>>();

GlitchyEditor/src/EditorContentManager.bf

@@ -367,7 +367,16 @@ class EditorContentManager : IContentManager
 
 		if (!_handleToAsset.TryGetValue(handle, out asset))
 		{
-			LoadAsset(handle, blocking);
+			AssetHandle handleAfterLoading = LoadAsset(handle, blocking);
+
+			if (handleAfterLoading == .Invalid)
+			{
+				// TODO: If the asset existed at some point, the cache might still know of it.
+				// Or we store the asset name somewhere else. (For the editor in the asset using it?)
+				asset = new NewPlaceholderAsset(handle, .Error);
+
+				AssignHandleAndManage(asset, handle);
+			}
 		}
 
 		if (var placeholder = asset as PlaceholderAsset)
@@ -401,6 +410,8 @@ class EditorContentManager : IContentManager
 
 	private Asset GetPlaceholderAsset(Type assetType, PlaceholderType placeholderType)
 	{
+		// TODO: Probably don't hardcode paths here.
+		// TODO: Probably verify existence at start of application.
 		switch (assetType)
 		{
 		case typeof(Texture2D):
@@ -414,6 +425,17 @@ class EditorContentManager : IContentManager
 				AssetHandle handle = LoadAsset("Resources/Textures/ErrorTexture2D.png", true);
 				return GetAsset(null, handle);
 			}
+		case typeof(Effect):
+			if (placeholderType == .Loading)
+			{
+				AssetHandle handle = LoadAsset("Resources/Shaders/PlaceholderLoading.fx", true);
+				return GetAsset(null, handle);
+			}
+			else if (placeholderType == .Error)
+			{
+				AssetHandle handle = LoadAsset("Resources/Shaders/PlaceholderError.fx", true);
+				return GetAsset(null, handle);
+			}
 		}
 
 		return null;
@@ -623,6 +645,7 @@ class EditorContentManager : IContentManager
 		using (_finishedEntriesLock.Enter())
 		{
 			loadedAsset.Identifier = assetNode.Identifier;
+			// TODO: AssignHandleAndManage
 			loadedAsset.[Friend]_contentManager = this;
 			loadedAsset.[Friend]_handle = handle;
 	
@@ -874,14 +897,23 @@ class EditorContentManager : IContentManager
 			// If this happens too often we could use a different random generator
 		}
 
-		//_handles.Add(asset.Identifier, handle);
+		AssignHandleAndManage(asset, handle);
+
+		return handle;
+	}
+
+	private void AssignHandleAndManage(Asset asset, AssetHandle handle)
+	{
+		if (_handleToAsset.TryGetValue(handle, let existingAsset))
+		{
+			existingAsset.ReleaseRef();
+		}
+
 		_handleToAsset.Add(handle, asset);
 
 		asset.[Friend]_contentManager = this;
 		asset.[Friend]_handle = handle;
 		asset.AddRef();
-
-		return handle;
 	}
 
 	private void SwapAsset(Asset oldAsset, Asset newAsset)