Enforce pointer alignment for InlinedAllocation

AssetReferences stored in inlined allocation needs to be aligned to
pointer sized boundary due to atomic operations having strict
requirements for such. Unaligned access seems to only crash on
Windows on ARM systems when trying to allocate TextRender draw chunks.

.github/workflows/build_ios.yml

@@ -19,7 +19,7 @@ jobs:
     - name: Setup .NET
       uses: actions/setup-dotnet@v3
       with:
-        dotnet-version: 8.0.x
+        dotnet-version: 9.0.x
     - name: Setup .NET Workload
       run: |
         dotnet workload install ios
@@ -33,4 +33,4 @@ jobs:
         git lfs pull
     - name: Build
       run: |
-        ./Development/Scripts/Mac/CallBuildTool.sh -build -log -dotnet=8 -arch=ARM64 -platform=iOS -configuration=Release -buildtargets=FlaxGame
+        ./Development/Scripts/Mac/CallBuildTool.sh -build -log -dotnet=9 -arch=ARM64 -platform=iOS -configuration=Release -buildtargets=FlaxGame

.github/workflows/build_linux.yml

@@ -16,7 +16,7 @@ jobs:
       uses: actions/checkout@v3
     - name: Install dependencies
       run: |
-        sudo apt-get install libx11-dev libxcursor-dev libxinerama-dev build-essential gettext libtool libtool-bin libpulse-dev libasound2-dev libjack-dev portaudio19-dev
+        sudo apt-get install libx11-dev libxcursor-dev libxinerama-dev build-essential gettext libtool libtool-bin libpulse-dev libasound2-dev libjack-dev portaudio19-dev libwayland-dev
     - name: Setup Vulkan
       uses: ./.github/actions/vulkan
     - name: Setup .NET
@@ -44,7 +44,7 @@ jobs:
       uses: actions/checkout@v3
     - name: Install dependencies
       run: |
-        sudo apt-get install libx11-dev libxcursor-dev libxinerama-dev
+        sudo apt-get install libx11-dev libxcursor-dev libxinerama-dev libwayland-dev
     - name: Setup Vulkan
       uses: ./.github/actions/vulkan
     - name: Setup .NET

.github/workflows/tests.yml

@@ -28,7 +28,7 @@ jobs:
         git lfs pull
     - name: Install dependencies
       run: |
-        sudo apt-get install libx11-dev libxcursor-dev libxinerama-dev build-essential gettext libtool libtool-bin libpulse-dev libasound2-dev libjack-dev portaudio19-dev
+        sudo apt-get install libx11-dev libxcursor-dev libxinerama-dev build-essential gettext libtool libtool-bin libpulse-dev libasound2-dev libjack-dev portaudio19-dev libwayland-dev
     - name: Build
       run: |
         ./GenerateProjectFiles.sh -vs2022 -log -verbose -printSDKs -dotnet=8

Content/Editor/MaterialTemplates/Decal.shader

@@ -6,6 +6,7 @@
 @3
 
 #include "./Flax/Common.hlsl"
+#include "./Flax/Stencil.hlsl"
 #include "./Flax/MaterialCommon.hlsl"
 #include "./Flax/GBufferCommon.hlsl"
 @7
@@ -14,10 +15,13 @@ META_CB_BEGIN(0, Data)
 float4x4 WorldMatrix;
 float4x4 InvWorld;
 float4x4 SvPositionToWorld;
+float3 Padding0;
+uint RenderLayersMask;
 @1META_CB_END
 
 // Use depth buffer for per-pixel decal layering
 Texture2D DepthBuffer : register(t0);
+Texture2D<uint2> StencilBuffer : register(t1);
 
 // Material shader resources
 @2
@@ -200,6 +204,14 @@ void PS_Decal(
 #endif
 	)
 {
+	// Stencil masking
+	uint stencilObjectLayer = STENCIL_BUFFER_OBJECT_LAYER(STENCIL_BUFFER_LOAD(StencilBuffer, SvPosition.xy));
+	if ((RenderLayersMask & (1 << stencilObjectLayer)) == 0)
+	{
+		clip(-1);
+		return;
+	}
+
 	float2 screenUV = SvPosition.xy * ScreenSize.zw;
 	SvPosition.z = SAMPLE_RT(DepthBuffer, screenUV).r;
 

Content/Editor/MaterialTemplates/Features/ForwardShading.hlsl

@@ -29,6 +29,13 @@ Buffer<float4> ShadowsBuffer : register(t__SRV__);
 Texture2D<float> ShadowMap : register(t__SRV__);
 Texture3D VolumetricFogTexture : register(t__SRV__);
 @4// Forward Shading: Utilities
+// Public accessors for lighting data, use them as data binding might change but those methods will remain.
+LightData GetDirectionalLight() { return DirectionalLight; }
+LightData GetSkyLight() { return SkyLight; }
+ProbeData GetEnvironmentProbe() { return EnvironmentProbe; }
+ExponentialHeightFogData GetExponentialHeightFog() { return ExponentialHeightFog; }
+uint GetLocalLightsCount() { return LocalLightsCount; }
+LightData GetLocalLight(uint i) { return LocalLights[i]; }
 @5// Forward Shading: Shaders
 
 // Pixel Shader function for Forward Pass
@@ -77,9 +84,8 @@ void PS_Forward(
 	gBuffer.ShadingModel = MATERIAL_SHADING_MODEL;
 
 	// Calculate lighting from a single directional light
-	float4 shadowMask = 1.0f;
 	ShadowSample shadow = SampleDirectionalLightShadow(DirectionalLight, ShadowsBuffer, ShadowMap, gBuffer);
-	shadowMask = GetShadowMask(shadow);
+	float4 shadowMask = GetShadowMask(shadow);
 	float4 light = GetLighting(ViewPos, DirectionalLight, gBuffer, shadowMask, false, false);
 
 	// Calculate lighting from sky light
@@ -146,7 +152,13 @@ void PS_Forward(
 
 #if USE_FOG && MATERIAL_SHADING_MODEL != SHADING_MODEL_UNLIT
 	// Calculate exponential height fog
-	float4 fog = GetExponentialHeightFog(ExponentialHeightFog, materialInput.WorldPosition, ViewPos, 0, gBuffer.ViewPos.z);
+#if DIRECTX && FEATURE_LEVEL < FEATURE_LEVEL_SM6
+	// TODO: fix D3D11/D3D10 bug with incorrect distance
+	float fogSceneDistance = distance(materialInput.WorldPosition, ViewPos);
+#else
+	float fogSceneDistance = gBuffer.ViewPos.z;
+#endif
+	float4 fog = GetExponentialHeightFog(ExponentialHeightFog, materialInput.WorldPosition, ViewPos, 0, fogSceneDistance);
 
 	if (ExponentialHeightFog.VolumetricFogMaxDistance > 0)
 	{

Content/Editor/MaterialTemplates/GUI.shader

@@ -21,7 +21,7 @@ float4 ViewInfo;
 float4 ScreenSize;
 float4 ViewSize;
 float3 ViewPadding0;
-float UnscaledTimeParam;
+float ScaledTimeParam;
 @1META_CB_END
 
 // Shader resources

Content/Editor/MaterialTemplates/PostProcess.shader

@@ -20,7 +20,7 @@ float4 ScreenSize;
 float4 TemporalAAJitter;
 float4x4 InverseViewProjectionMatrix;
 float3 ViewPadding0;
-float UnscaledTimeParam;
+float ScaledTimeParam;
 @1META_CB_END
 
 // Shader resources

Flax.flaxproj

@@ -2,9 +2,9 @@
   "Name": "Flax",
   "Version": {
     "Major": 1,
-    "Minor": 10,
+    "Minor": 11,
     "Revision": 0,
-    "Build": 6705
+    "Build": 6801
   },
   "Company": "Flax",
   "Copyright": "Copyright (c) 2012-2025 Wojciech Figat. All rights reserved.",
@@ -13,6 +13,7 @@
   "Configuration": {
     "UseCSharp": true,
     "UseLargeWorlds": false,
-    "UseDotNet": true
+    "UseDotNet": true,
+    "UseSDL": true
   }
 }

Source/Editor/Analytics/EditorAnalytics.cpp

@@ -174,7 +174,9 @@ void EditorAnalytics::StartSession()
     // Bind events
     GameCooker::OnEvent.Bind<RegisterGameCookingStart>();
     ShadowsOfMordor::Builder::Instance()->OnBuildStarted.Bind<RegisterLightmapsBuildingStart>();
+#if LOG_ENABLE
     Log::Logger::OnError.Bind<RegisterError>();
+#endif
 }
 
 void EditorAnalytics::EndSession()
@@ -187,7 +189,9 @@ void EditorAnalytics::EndSession()
     // Unbind events
     GameCooker::OnEvent.Unbind<RegisterGameCookingStart>();
     ShadowsOfMordor::Builder::Instance()->OnBuildStarted.Unbind<RegisterLightmapsBuildingStart>();
+#if LOG_ENABLE
     Log::Logger::OnError.Unbind<RegisterError>();
+#endif
 
     // End session
     {

Source/Editor/Content/Items/ContentFolder.cs

@@ -282,7 +282,7 @@ namespace FlaxEditor.Content
 
             if (data is DragDataFiles)
                 return DragDropEffect.Copy;
-            return _dragOverItems.Effect;
+            return _dragOverItems?.Effect ?? DragDropEffect.None;
         }
 
         /// <inheritdoc />

Source/Editor/Content/Items/CppScriptItem.cs

@@ -20,7 +20,7 @@ namespace FlaxEditor.Content
         }
 
         /// <inheritdoc />
-        public override string TypeDescription => Path.EndsWith(".h") ? "C++ Header File" : "C++ Source Code";
+        public override string TypeDescription => Path.EndsWith(".h") || Path.EndsWith(".hpp") ? "C++ Header File" : "C++ Source Code";
 
         /// <inheritdoc />
         public override SpriteHandle DefaultThumbnail => Editor.Instance.Icons.CPPScript128;

Source/Editor/Cooker/CookingData.h

@@ -20,13 +20,6 @@ class PlatformTools;
 #define GAME_BUILD_DOTNET_RUNTIME_MAX_VER 9
 #endif
 
-#if OFFICIAL_BUILD
-// Use the fixed .NET SDK version in packaged builds for compatibility (FlaxGame is precompiled with it)
-#define GAME_BUILD_DOTNET_VER TEXT("-dotnet=" MACRO_TO_STR(GAME_BUILD_DOTNET_RUNTIME_MIN_VER))
-#else
-#define GAME_BUILD_DOTNET_VER TEXT("")
-#endif
-
 /// <summary>
 /// Game building options. Used as flags.
 /// </summary>
@@ -374,6 +367,8 @@ public:
     /// </summary>
     void GetBuildPlatformName(const Char*& platform, const Char*& architecture) const;
 
+    String GetDotnetCommandArg() const;
+
 public:
 
     /// <summary>

Source/Editor/Cooker/GameCooker.cpp

@@ -30,6 +30,7 @@
 #include "Engine/Scripting/ManagedCLR/MAssembly.h"
 #include "Engine/Content/JsonAsset.h"
 #include "Engine/Content/AssetReference.h"
+#include "Engine/Profiler/ProfilerMemory.h"
 #if PLATFORM_TOOLS_WINDOWS
 #include "Platform/Windows/WindowsPlatformTools.h"
 #include "Engine/Platform/Windows/WindowsPlatformSettings.h"
@@ -311,6 +312,14 @@ void CookingData::GetBuildPlatformName(const Char*& platform, const Char*& archi
     }
 }
 
+String CookingData::GetDotnetCommandArg() const
+{
+    int32 version = Tools->GetDotnetVersion();
+    if (version == 0)
+        return String::Empty;
+    return String::Format(TEXT("-dotnet={}"), version);
+}
+
 void CookingData::StepProgress(const String& info, const float stepProgress) const
 {
     const float singleStepProgress = 1.0f / (StepsCount + 1);
@@ -380,6 +389,7 @@ bool GameCooker::IsCancelRequested()
 
 PlatformTools* GameCooker::GetTools(BuildPlatform platform)
 {
+    PROFILE_MEM(Editor);
     PlatformTools* result = nullptr;
     if (!Tools.TryGet(platform, result))
     {
@@ -471,6 +481,7 @@ bool GameCooker::Build(BuildPlatform platform, BuildConfiguration configuration,
         LOG(Error, "Build platform {0} is not supported.", ::ToString(platform));
         return true;
     }
+    PROFILE_MEM(Editor);
 
     // Setup
     CancelFlag = 0;
@@ -624,6 +635,7 @@ void GameCookerImpl::ReportProgress(const String& info, float totalProgress)
 
 void GameCookerImpl::OnCollectAssets(HashSet<Guid>& assets)
 {
+    PROFILE_MEM(Editor);
     if (Internal_OnCollectAssets == nullptr)
     {
         auto c = GameCooker::GetStaticClass();
@@ -651,6 +663,7 @@ void GameCookerImpl::OnCollectAssets(HashSet<Guid>& assets)
 
 bool GameCookerImpl::Build()
 {
+    PROFILE_MEM(Editor);
     CookingData& data = *Data;
     LOG(Info, "Starting Game Cooker...");
     LOG(Info, "Platform: {0}, Configuration: {2}, Options: {1}", ::ToString(data.Platform), (int32)data.Options, ::ToString(data.Configuration));
@@ -670,8 +683,7 @@ bool GameCookerImpl::Build()
 
     MCore::Thread::Attach();
 
-    // Build Started
-    if (!EnumHasAnyFlags(data.Options, BuildOptions::NoCook))
+    // Build start
     {
         CallEvent(GameCooker::EventType::BuildStarted);
         data.Tools->OnBuildStarted(data);
@@ -744,8 +756,8 @@ bool GameCookerImpl::Build()
     }
     IsRunning = false;
     CancelFlag = 0;
-    if (!EnumHasAnyFlags(data.Options, BuildOptions::NoCook))
     {
+        // Build end
         for (int32 stepIndex = 0; stepIndex < Steps.Count(); stepIndex++)
             Steps[stepIndex]->OnBuildEnded(data, failed);
         data.Tools->OnBuildEnded(data, failed);
@@ -778,6 +790,8 @@ int32 GameCookerImpl::ThreadFunction()
 
 bool GameCookerService::Init()
 {
+    PROFILE_MEM(Editor);
+
     auto editorAssembly = ((NativeBinaryModule*)GetBinaryModuleFlaxEngine())->Assembly;
     editorAssembly->Unloading.Bind(OnEditorAssemblyUnloading);
     GameCooker::OnCollectAssets.Bind(OnCollectAssets);
@@ -789,6 +803,7 @@ void GameCookerService::Update()
 {
     if (IsRunning)
     {
+        PROFILE_MEM(Editor);
         ScopeLock lock(ProgressLocker);
 
         if (ProgressMsg.HasChars())

Source/Editor/Cooker/Platform/GDK/GDKPlatformTools.cpp

@@ -195,4 +195,9 @@ bool GDKPlatformTools::OnPostProcess(CookingData& data, GDKPlatformSettings* pla
     return false;
 }
 
+int32 GDKPlatformTools::GetDotnetVersion() const
+{
+    return GAME_BUILD_DOTNET_RUNTIME_MIN_VER;
+}
+
 #endif

Source/Editor/Cooker/Platform/GDK/GDKPlatformTools.h

@@ -26,6 +26,7 @@ public:
 public:
 
     // [PlatformTools]
+    int32 GetDotnetVersion() const override;
     DotNetAOTModes UseAOT() const override;
     bool OnDeployBinaries(CookingData& data) override;
 };

Source/Editor/Cooker/Platform/Mac/MacPlatformTools.cpp

@@ -186,7 +186,7 @@ bool MacPlatformTools::OnPostProcess(CookingData& data)
         ADD_ENTRY("CFBundlePackageType", "APPL");
         ADD_ENTRY("NSPrincipalClass", "NSApplication");
         ADD_ENTRY("LSApplicationCategoryType", "public.app-category.games");
-        ADD_ENTRY("LSMinimumSystemVersion", "10.15");
+        ADD_ENTRY("LSMinimumSystemVersion", "13");
         ADD_ENTRY("CFBundleIconFile", "icon.icns");
         ADD_ENTRY_STR("CFBundleExecutable", executableName);
         ADD_ENTRY_STR("CFBundleIdentifier", appIdentifier);
@@ -231,6 +231,8 @@ bool MacPlatformTools::OnPostProcess(CookingData& data)
     LOG(Info, "Building app package...");
     {
         const String dmgPath = data.OriginalOutputPath / appName + TEXT(".dmg");
+        if (FileSystem::FileExists(dmgPath))
+            FileSystem::DeleteFile(dmgPath);
         CreateProcessSettings procSettings;
         procSettings.HiddenWindow = true;
         procSettings.WorkingDirectory = data.OriginalOutputPath;

Source/Editor/Cooker/Platform/Windows/WindowsPlatformTools.cpp

@@ -528,6 +528,9 @@ bool WindowsPlatformTools::OnDeployBinaries(CookingData& data)
 
 void WindowsPlatformTools::OnBuildStarted(CookingData& data)
 {
+    if (EnumHasAllFlags(data.Options, BuildOptions::NoCook))
+        return;
+
     // Remove old executable
     Array<String> files;
     FileSystem::DirectoryGetFiles(files, data.NativeCodeOutputPath, TEXT("*.exe"), DirectorySearchOption::TopDirectoryOnly);

Source/Editor/Cooker/PlatformTools.h

@@ -70,6 +70,20 @@ public:
     /// </summary>
     virtual ArchitectureType GetArchitecture() const = 0;
 
+    /// <summary>
+    /// Gets the .Net version to use for the cooked game.
+    /// </summary>
+    virtual int32 GetDotnetVersion() const
+    {
+#if OFFICIAL_BUILD
+        // Use the fixed .NET SDK version in packaged builds for compatibility (FlaxGame is precompiled with it)
+        return GAME_BUILD_DOTNET_RUNTIME_MIN_VER;
+#else
+        // Use the highest version found on a system (Flax.Build will decide)
+        return 0;
+#endif
+    }
+
     /// <summary>
     /// Gets the value indicating whenever platform requires AOT (needs C# assemblies to be precompiled).
     /// </summary>

Source/Editor/Cooker/Steps/CompileScriptsStep.cpp

@@ -189,7 +189,7 @@ bool CompileScriptsStep::Perform(CookingData& data)
     const String logFile = data.CacheDirectory / TEXT("CompileLog.txt");
     auto args = String::Format(
         TEXT("-log -logfile=\"{4}\" -build -mutex -buildtargets={0} -platform={1} -arch={2} -configuration={3} -aotMode={5} {6}"),
-        target, platform, architecture, configuration, logFile, ToString(data.Tools->UseAOT()), GAME_BUILD_DOTNET_VER);
+        target, platform, architecture, configuration, logFile, ToString(data.Tools->UseAOT()), data.GetDotnetCommandArg());
 #if PLATFORM_WINDOWS
     if (data.Platform == BuildPlatform::LinuxX64)
 #elif PLATFORM_LINUX

Source/Editor/Cooker/Steps/CookAssetsStep.cpp

@@ -36,6 +36,7 @@
 #include "Engine/Engine/Base/GameBase.h"
 #include "Engine/Engine/Globals.h"
 #include "Engine/Tools/TextureTool/TextureTool.h"
+#include "Engine/Threading/Threading.h"
 #include "Engine/Profiler/ProfilerCPU.h"
 #include "Engine/Scripting/Enums.h"
 #if PLATFORM_TOOLS_WINDOWS

Source/Editor/Cooker/Steps/DeployDataStep.cpp

@@ -88,7 +88,7 @@ bool DeployDataStep::Perform(CookingData& data)
             {
                 // Ask Flax.Build to provide .NET SDK location for the current platform
                 String sdks;
-                bool failed = ScriptsBuilder::RunBuildTool(String::Format(TEXT("-log -logMessagesOnly -logFileWithConsole -logfile=SDKs.txt -printSDKs {}"), GAME_BUILD_DOTNET_VER), data.CacheDirectory);
+                bool failed = ScriptsBuilder::RunBuildTool(String::Format(TEXT("-log -logMessagesOnly -logFileWithConsole -logfile=SDKs.txt -printSDKs {}"), data.GetDotnetCommandArg()), data.CacheDirectory);
                 failed |= File::ReadAllText(data.CacheDirectory / TEXT("SDKs.txt"), sdks);
                 int32 idx = sdks.Find(TEXT("DotNetSdk, "), StringSearchCase::CaseSensitive);
                 if (idx != -1)
@@ -200,7 +200,7 @@ bool DeployDataStep::Perform(CookingData& data)
                 String sdks;
                 const Char *platformName, *archName;
                 data.GetBuildPlatformName(platformName, archName);
-                String args = String::Format(TEXT("-log -logMessagesOnly -logFileWithConsole -logfile=SDKs.txt -printDotNetRuntime -platform={} -arch={} {}"), platformName, archName, GAME_BUILD_DOTNET_VER);
+                String args = String::Format(TEXT("-log -logMessagesOnly -logFileWithConsole -logfile=SDKs.txt -printDotNetRuntime -platform={} -arch={} {}"), platformName, archName, data.GetDotnetCommandArg());
                 bool failed = ScriptsBuilder::RunBuildTool(args, data.CacheDirectory);
                 failed |= File::ReadAllText(data.CacheDirectory / TEXT("SDKs.txt"), sdks);
                 Array<String> parts;
@@ -244,10 +244,13 @@ bool DeployDataStep::Perform(CookingData& data)
                     }
                     if (version.IsEmpty())
                     {
+                        int32 minVer = GAME_BUILD_DOTNET_RUNTIME_MIN_VER, maxVer = GAME_BUILD_DOTNET_RUNTIME_MAX_VER;
                         if (srcDotnetFromEngine)
                         {
                             // Detect version from runtime files inside Engine Platform folder
-                            for (int32 i = GAME_BUILD_DOTNET_RUNTIME_MAX_VER; i >= GAME_BUILD_DOTNET_RUNTIME_MIN_VER; i--)
+                            if (data.Tools->GetDotnetVersion() != 0)
+                                minVer = maxVer = data.Tools->GetDotnetVersion();
+                            for (int32 i = maxVer; i >= minVer; i--)
                             {
                                 // Check runtime files inside Engine Platform folder
                                 String testPath1 = srcDotnet / String::Format(TEXT("lib/net{}.0"), i);
@@ -262,7 +265,7 @@ bool DeployDataStep::Perform(CookingData& data)
                         }
                         if (version.IsEmpty())
                         {
-                            data.Error(String::Format(TEXT("Failed to find supported .NET {} version for the current host platform."), GAME_BUILD_DOTNET_RUNTIME_MIN_VER));
+                            data.Error(String::Format(TEXT("Failed to find supported .NET {} version (min {}) for the current host platform."), maxVer, minVer));
                             return true;
                         }
                     }
@@ -364,7 +367,7 @@ bool DeployDataStep::Perform(CookingData& data)
             const String logFile = data.CacheDirectory / TEXT("StripDotnetLibs.txt");
             String args = String::Format(
                 TEXT("-log -logfile=\"{}\" -runDotNetClassLibStripping -mutex -binaries=\"{}\" {}"),
-                logFile, data.DataOutputPath, GAME_BUILD_DOTNET_VER);
+                logFile, data.DataOutputPath, data.GetDotnetCommandArg());
             for (const String& define : data.CustomDefines)
             {
                 args += TEXT(" -D");

Source/Editor/Cooker/Steps/PrecompileAssembliesStep.cpp

@@ -12,7 +12,7 @@
 void PrecompileAssembliesStep::OnBuildStarted(CookingData& data)
 {
     const DotNetAOTModes aotMode = data.Tools->UseAOT();
-    if (aotMode == DotNetAOTModes::None)
+    if (aotMode == DotNetAOTModes::None || EnumHasAllFlags(data.Options, BuildOptions::NoCook))
         return;
     const auto& buildSettings = *BuildSettings::Get();
 
@@ -69,7 +69,7 @@ bool PrecompileAssembliesStep::Perform(CookingData& data)
     const String logFile = data.CacheDirectory / TEXT("AOTLog.txt");
     String args = String::Format(
         TEXT("-log -logfile=\"{}\" -runDotNetAOT -mutex -platform={} -arch={} -configuration={} -aotMode={} -binaries=\"{}\" -intermediate=\"{}\" {}"),
-        logFile, platform, architecture, configuration, ToString(aotMode), data.DataOutputPath, data.ManagedCodeOutputPath, GAME_BUILD_DOTNET_VER);
+        logFile, platform, architecture, configuration, ToString(aotMode), data.DataOutputPath, data.ManagedCodeOutputPath, data.GetDotnetCommandArg());
     if (!buildSettings.SkipUnusedDotnetLibsPackaging)
         args += TEXT(" -skipUnusedDotnetLibs=false"); // Run AOT on whole class library (not just used libs)
     for (const String& define : data.CustomDefines)

Source/Editor/CustomEditors/CustomEditorsUtil.cpp

@@ -6,6 +6,8 @@
 #include "Engine/Core/Types/TimeSpan.h"
 #include "Engine/Core/Types/Stopwatch.h"
 #include "Engine/Core/Collections/Dictionary.h"
+#include "Engine/Profiler/ProfilerCPU.h"
+#include "Engine/Profiler/ProfilerMemory.h"
 #include "Engine/Engine/EngineService.h"
 #include "Engine/Scripting/Scripting.h"
 #include "Engine/Scripting/BinaryModule.h"
@@ -69,6 +71,7 @@ MTypeObject* CustomEditorsUtil::GetCustomEditor(MTypeObject* refType)
 
 bool CustomEditorsUtilService::Init()
 {
+    PROFILE_MEM(Editor);
     TRACK_ASSEMBLY(((NativeBinaryModule*)GetBinaryModuleFlaxEngine())->Assembly);
     Scripting::BinaryModuleLoaded.Bind(&OnBinaryModuleLoaded);
 
@@ -77,6 +80,8 @@ bool CustomEditorsUtilService::Init()
 
 void OnAssemblyLoaded(MAssembly* assembly)
 {
+    PROFILE_CPU_NAMED("CustomEditors.OnAssemblyLoaded");
+    PROFILE_MEM(Editor);
     Stopwatch stopwatch;
 
     // Prepare FlaxEngine

Source/Editor/CustomEditors/Dedicated/LocalizationSettingsEditor.cs

@@ -190,12 +190,12 @@ namespace FlaxEditor.CustomEditors.Dedicated
                     foreach (var file in files)
                         FindNewKeysCSharp(file, newKeys, allKeys);
 
-                    // C++
-                    files = Directory.GetFiles(Globals.ProjectSourceFolder, "*.cpp", SearchOption.AllDirectories);
+                    // C/C++
+                    files = Directory.GetFiles(Globals.ProjectSourceFolder, "*.cpp", SearchOption.AllDirectories).Concat(Directory.GetFiles(Globals.ProjectSourceFolder, "*.c", SearchOption.AllDirectories)).ToArray();
                     filesCount += files.Length;
                     foreach (var file in files)
                         FindNewKeysCpp(file, newKeys, allKeys);
-                    files = Directory.GetFiles(Globals.ProjectSourceFolder, "*.h", SearchOption.AllDirectories);
+                    files = Directory.GetFiles(Globals.ProjectSourceFolder, "*.h", SearchOption.AllDirectories).Concat(Directory.GetFiles(Globals.ProjectSourceFolder, "*.hpp", SearchOption.AllDirectories)).ToArray();;
                     filesCount += files.Length;
                     foreach (var file in files)
                         FindNewKeysCpp(file, newKeys, allKeys);

Source/Editor/CustomEditors/Editors/ControlReferenceEditor.cs

@@ -22,7 +22,7 @@ internal class UIControlRefPickerControl : FlaxObjectRefPickerControl
     /// <inheritdoc />
     protected override bool IsValid(Object obj)
     {
-        return obj == null || (obj is UIControl control && control.Control.GetType() == ControlType);
+        return obj == null || (obj is UIControl control && ControlType.IsAssignableFrom(control.Control.GetType()));
     }
 }
 

Source/Editor/Editor.cpp

@@ -20,6 +20,7 @@
 #include "Engine/Engine/Engine.h"
 #include "Engine/ShadowsOfMordor/Builder.h"
 #include "Engine/Profiler/ProfilerCPU.h"
+#include "Engine/Profiler/ProfilerMemory.h"
 #include "FlaxEngine.Gen.h"
 #if PLATFORM_LINUX
 #include "Engine/Tools/TextureTool/TextureTool.h"
@@ -47,6 +48,7 @@ void Editor::CloseSplashScreen()
 
 bool Editor::CheckProjectUpgrade()
 {
+    PROFILE_MEM(Editor);
     const auto versionFilePath = Globals::ProjectCacheFolder / TEXT("version");
 
     // Load version cache file
@@ -266,8 +268,8 @@ bool Editor::CheckProjectUpgrade()
     // Check if last version was older
     else if (lastVersion.Major < FLAXENGINE_VERSION_MAJOR || (lastVersion.Major == FLAXENGINE_VERSION_MAJOR && lastVersion.Minor < FLAXENGINE_VERSION_MINOR))
     {
-        LOG(Warning, "The project was opened with the older editor version last time");
-        const auto result = MessageBox::Show(TEXT("The project was opened with the older editor version last time. Loading it may modify existing data so older editor version won't open it. Do you want to perform a backup before or cancel operation?"), TEXT("Project upgrade"), MessageBoxButtons::YesNoCancel, MessageBoxIcon::Question);
+        LOG(Warning, "The project was last opened with an older editor version");
+        const auto result = MessageBox::Show(TEXT("The project was last opened with an older editor version.\nLoading it may modify existing data, which can result in older editor versions being unable to open it.\n\nDo you want to perform a backup before or cancel the operation?"), TEXT("Project upgrade"), MessageBoxButtons::YesNoCancel, MessageBoxIcon::Question);
         if (result == DialogResult::Yes)
         {
             if (BackupProject())
@@ -289,8 +291,8 @@ bool Editor::CheckProjectUpgrade()
     // Check if last version was newer
     else if (lastVersion.Major > FLAXENGINE_VERSION_MAJOR || (lastVersion.Major == FLAXENGINE_VERSION_MAJOR && lastVersion.Minor > FLAXENGINE_VERSION_MINOR))
     {
-        LOG(Warning, "The project was opened with the newer editor version last time");
-        const auto result = MessageBox::Show(TEXT("The project was opened with the newer editor version last time. Loading it may fail and corrupt existing data. Do you want to perform a backup before or cancel operation?"), TEXT("Project upgrade"), MessageBoxButtons::YesNoCancel, MessageBoxIcon::Warning);
+        LOG(Warning, "The project was last opened with a newer editor version");
+        const auto result = MessageBox::Show(TEXT("The project was last opened with a newer editor version.\nLoading it may fail and corrupt existing data.\n\nDo you want to perform a backup before loading or cancel the operation?"), TEXT("Project upgrade"), MessageBoxButtons::YesNoCancel, MessageBoxIcon::Warning);
         if (result == DialogResult::Yes)
         {
             if (BackupProject())
@@ -366,6 +368,8 @@ bool Editor::BackupProject()
 
 int32 Editor::LoadProduct()
 {
+    PROFILE_MEM(Editor);
+
     // Flax Editor product
     Globals::ProductName = TEXT("Flax Editor");
     Globals::CompanyName = TEXT("Flax");
@@ -626,6 +630,7 @@ int32 Editor::LoadProduct()
 
 Window* Editor::CreateMainWindow()
 {
+    PROFILE_MEM(Editor);
     Window* window = Managed->GetMainWindow();
 
 #if PLATFORM_LINUX
@@ -662,6 +667,7 @@ bool Editor::Init()
         return true;
     }
     PROFILE_CPU();
+    PROFILE_MEM(Editor);
 
     // If during last lightmaps baking engine crashed we could try to restore the progress
     ShadowsOfMordor::Builder::Instance()->CheckIfRestoreState();
@@ -693,11 +699,13 @@ bool Editor::Init()
 
 void Editor::BeforeRun()
 {
+    PROFILE_MEM(Editor);
     Managed->BeforeRun();
 }
 
 void Editor::BeforeExit()
 {
+    PROFILE_MEM(Editor);
     CloseSplashScreen();
 
     Managed->Exit();
@@ -708,6 +716,8 @@ void Editor::BeforeExit()
 
 void EditorImpl::OnUpdate()
 {
+    PROFILE_MEM(Editor);
+
     // Update c# editor
     Editor::Managed->Update();
 

Source/Editor/GUI/ColumnDefinition.cs

@@ -51,7 +51,7 @@ namespace FlaxEditor.GUI
         /// <summary>
         /// The column title horizontal text alignment
         /// </summary>
-        public TextAlignment TitleAlignment = TextAlignment.Near;
+        public TextAlignment TitleAlignment = TextAlignment.Center;
 
         /// <summary>
         /// The column title margin.

Source/Editor/GUI/ContextMenu/ContextMenuBase.cs

@@ -1,7 +1,10 @@
-#if PLATFORM_WINDOWS
+#if PLATFORM_WINDOWS || PLATFORM_SDL
 #define USE_IS_FOREGROUND
 #else
 #endif
+#if PLATFORM_SDL
+#define USE_SDL_WORKAROUNDS
+#endif
 // Copyright (c) Wojciech Figat. All rights reserved.
 
 using System.Collections.Generic;
@@ -114,14 +117,15 @@ namespace FlaxEditor.GUI.ContextMenu
         public ContextMenuBase()
         : base(0, 0, 120, 32)
         {
-            _direction = ContextMenuDirection.RightDown;
             Visible = false;
+            AutoFocus = true;
 
+            _direction = ContextMenuDirection.RightDown;
             _isSubMenu = true;
         }
 
         /// <summary>
-        /// Shows the empty menu popup o na screen.
+        /// Shows the empty menu popup on a screen.
         /// </summary>
         /// <param name="control">The target control.</param>
         /// <param name="area">The target control area to cover.</param>
@@ -256,7 +260,9 @@ namespace FlaxEditor.GUI.ContextMenu
                 desc.AllowMaximize = false;
                 desc.AllowDragAndDrop = false;
                 desc.IsTopmost = true;
-                desc.IsRegularWindow = false;
+                desc.Type = WindowType.Popup;
+                desc.Parent = parentWin.Window;
+                desc.Title = "ContextMenu";
                 desc.HasSizingFrame = false;
                 OnWindowCreating(ref desc);
                 _window = Platform.CreateWindow(ref desc);
@@ -265,6 +271,12 @@ namespace FlaxEditor.GUI.ContextMenu
                     _window.GotFocus += OnWindowGotFocus;
                     _window.LostFocus += OnWindowLostFocus;
                 }
+                
+#if USE_IS_FOREGROUND && USE_SDL_WORKAROUNDS
+                // The focus between popup and parent windows doesn't change, force hide the popup when clicked on parent
+                parentWin.Window.MouseDown += OnWindowMouseDown;
+                _window.Closed += () => parentWin.Window.MouseDown -= OnWindowMouseDown;
+#endif
 
                 // Attach to the window
                 _parentCM = parent as ContextMenuBase;
@@ -440,6 +452,17 @@ namespace FlaxEditor.GUI.ContextMenu
             }
         }
 
+#if USE_SDL_WORKAROUNDS
+        private void OnWindowGotFocus()
+        {
+        }
+        
+        private void OnWindowMouseDown(ref Float2 mousePosition, MouseButton button, ref bool handled)
+        {
+            // The user clicked outside the popup window
+            Hide();
+        }
+#else
         private void OnWindowGotFocus()
         {
             var child = _childCM;
@@ -453,6 +476,7 @@ namespace FlaxEditor.GUI.ContextMenu
                 });
             }
         }
+#endif
 
         private void OnWindowLostFocus()
         {
@@ -551,7 +575,12 @@ namespace FlaxEditor.GUI.ContextMenu
             // Let root context menu to check if none of the popup windows
             if (_parentCM == null && UseVisibilityControl && !IsForeground)
             {
+#if USE_SDL_WORKAROUNDS
+                if (!IsMouseOver)
+                    Hide();
+#else
                 Hide();
+#endif
             }
         }
 #endif

Source/Editor/GUI/Dialogs/ColorPickerDialog.cs

@@ -326,8 +326,11 @@ namespace FlaxEditor.GUI.Dialogs
             // Update eye dropper tool
             if (_activeEyedropper)
             {
+                // Try reading the color under the cursor in realtime if supported by the platform
                 Float2 mousePosition = Platform.MousePosition;
-                SelectedColor = ScreenUtilities.GetColorAt(mousePosition);
+                Color color = ScreenUtilities.GetColorAt(mousePosition);
+                if (color != Color.Transparent)
+                    SelectedColor = color;
             }
         }
 

Source/Editor/GUI/Dialogs/ColorSelector.cs

@@ -76,6 +76,8 @@ namespace FlaxEditor.GUI.Dialogs
         public ColorSelector(float wheelSize)
         : base(0, 0, wheelSize, wheelSize)
         {
+            AutoFocus = true;
+
             _colorWheelSprite = Editor.Instance.Icons.ColorWheel128;
             _wheelRect = new Rectangle(0, 0, wheelSize, wheelSize);
         }

Source/Editor/GUI/Docking/DockHintWindow.cs

@@ -1,545 +0,0 @@
-// Copyright (c) Wojciech Figat. All rights reserved.
-
-using System;
-using FlaxEngine;
-using FlaxEngine.GUI;
-
-namespace FlaxEditor.GUI.Docking
-{
-    /// <summary>
-    /// Helper class used to handle docking windows dragging and docking.
-    /// </summary>
-    public class DockHintWindow
-    {
-        private FloatWindowDockPanel _toMove;
-
-        private Float2 _dragOffset;
-        private Float2 _defaultWindowSize;
-        private Rectangle _rectDock;
-        private Rectangle _rectWindow;
-        private Float2 _mouse;
-        private DockState _toSet;
-        private DockPanel _toDock;
-        private bool _lateDragOffsetUpdate;
-
-        private Rectangle _rLeft, _rRight, _rBottom, _rUpper, _rCenter;
-
-        private DockHintWindow(FloatWindowDockPanel toMove)
-        {
-            _toMove = toMove;
-            _toSet = DockState.Float;
-            var window = toMove.Window.Window;
-
-            // Remove focus from drag target
-            _toMove.Focus();
-            _toMove.Defocus();
-
-            // Focus window
-            window.Focus();
-
-            // Check if window is maximized and restore window.
-            if (window.IsMaximized)
-            {
-                // Restore window and set position to mouse.
-                var mousePos = window.MousePosition;
-                var previousSize = window.Size;
-                window.Restore();
-                window.Position = Platform.MousePosition - mousePos * window.Size / previousSize;
-            }
-
-            // Calculate dragging offset and move window to the destination position
-            var mouseScreenPosition = Platform.MousePosition;
-
-            // If the _toMove window was not focused when initializing this window, the result vector only contains zeros
-            // and to prevent a failure, we need to perform an update for the drag offset at later time which will be done in the OnMouseMove event handler.
-            if (mouseScreenPosition != Float2.Zero)
-                CalculateDragOffset(mouseScreenPosition);
-            else
-                _lateDragOffsetUpdate = true;
-
-            // Get initial size
-            _defaultWindowSize = window.Size;
-
-            // Init proxy window
-            Proxy.Init(ref _defaultWindowSize);
-
-            // Bind events
-            Proxy.Window.MouseUp += OnMouseUp;
-            Proxy.Window.MouseMove += OnMouseMove;
-            Proxy.Window.LostFocus += OnLostFocus;
-
-            // Start tracking mouse
-            Proxy.Window.StartTrackingMouse(false);
-
-            // Update window GUI
-            Proxy.Window.GUI.PerformLayout();
-
-            // Update rectangles
-            UpdateRects();
-
-            // Hide base window
-            window.Hide();
-
-            // Enable hit window presentation
-            Proxy.Window.RenderingEnabled = true;
-            Proxy.Window.Show();
-            Proxy.Window.Focus();
-        }
-
-        /// <summary>
-        /// Releases unmanaged and - optionally - managed resources.
-        /// </summary>
-        public void Dispose()
-        {
-            // End tracking mouse
-            Proxy.Window.EndTrackingMouse();
-
-            // Disable rendering
-            Proxy.Window.RenderingEnabled = false;
-
-            // Unbind events
-            Proxy.Window.MouseUp -= OnMouseUp;
-            Proxy.Window.MouseMove -= OnMouseMove;
-            Proxy.Window.LostFocus -= OnLostFocus;
-
-            // Hide the proxy
-            Proxy.Hide();
-
-            if (_toMove == null)
-                return;
-
-            // Check if window won't be docked
-            if (_toSet == DockState.Float)
-            {
-                var window = _toMove.Window?.Window;
-                if (window == null)
-                    return;
-                var mouse = Platform.MousePosition;
-
-                // Move base window
-                window.Position = mouse - _dragOffset;
-
-                // Show base window
-                window.Show();
-            }
-            else
-            {
-                bool hasNoChildPanels = _toMove.ChildPanelsCount == 0;
-
-                // Check if window has only single tab
-                if (hasNoChildPanels && _toMove.TabsCount == 1)
-                {
-                    // Dock window
-                    _toMove.GetTab(0).Show(_toSet, _toDock);
-                }
-                // Check if dock as tab and has no child panels
-                else if (hasNoChildPanels && _toSet == DockState.DockFill)
-                {
-                    // Dock all tabs
-                    while (_toMove.TabsCount > 0)
-                    {
-                        _toMove.GetTab(0).Show(DockState.DockFill, _toDock);
-                    }
-                }
-                else
-                {
-                    var selectedTab = _toMove.SelectedTab;
-
-                    // Dock the first tab into the target location
-                    var firstTab = _toMove.GetTab(0);
-                    firstTab.Show(_toSet, _toDock);
-
-                    // Dock rest of the tabs
-                    while (_toMove.TabsCount > 0)
-                    {
-                        _toMove.GetTab(0).Show(DockState.DockFill, firstTab);
-                    }
-
-                    // Keep selected tab being selected
-                    selectedTab?.SelectTab();
-                }
-
-                // Focus target window
-                _toDock.Root.Focus();
-            }
-
-            _toMove = null;
-        }
-
-        /// <summary>
-        /// Creates the new dragging hit window.
-        /// </summary>
-        /// <param name="toMove">Floating dock panel to move.</param>
-        /// <returns>The dock hint window object.</returns>
-        public static DockHintWindow Create(FloatWindowDockPanel toMove)
-        {
-            if (toMove == null)
-                throw new ArgumentNullException();
-
-            return new DockHintWindow(toMove);
-        }
-
-        /// <summary>
-        /// Creates the new dragging hit window.
-        /// </summary>
-        /// <param name="toMove">Dock window to move.</param>
-        /// <returns>The dock hint window object.</returns>
-        public static DockHintWindow Create(DockWindow toMove)
-        {
-            if (toMove == null)
-                throw new ArgumentNullException();
-
-            // Show floating
-            toMove.ShowFloating();
-
-            // Move window to the mouse position (with some offset for caption bar)
-            var window = (WindowRootControl)toMove.Root;
-            var mouse = Platform.MousePosition;
-            window.Window.Position = mouse - new Float2(8, 8);
-
-            // Get floating panel
-            var floatingPanelToMove = window.GetChild(0) as FloatWindowDockPanel;
-
-            return new DockHintWindow(floatingPanelToMove);
-        }
-
-        /// <summary>
-        /// Calculates window rectangle in the dock window.
-        /// </summary>
-        /// <param name="state">Window dock state.</param>
-        /// <param name="rect">Dock panel rectangle.</param>
-        /// <returns>Calculated window rectangle.</returns>
-        public static Rectangle CalculateDockRect(DockState state, ref Rectangle rect)
-        {
-            Rectangle result = rect;
-            switch (state)
-            {
-            case DockState.DockFill:
-                result.Location.Y += Editor.Instance.Options.Options.Interface.TabHeight;
-                result.Size.Y -= Editor.Instance.Options.Options.Interface.TabHeight;
-                break;
-            case DockState.DockTop:
-                result.Size.Y *= DockPanel.DefaultSplitterValue;
-                break;
-            case DockState.DockLeft:
-                result.Size.X *= DockPanel.DefaultSplitterValue;
-                break;
-            case DockState.DockBottom:
-                result.Location.Y += result.Size.Y * (1 - DockPanel.DefaultSplitterValue);
-                result.Size.Y *= DockPanel.DefaultSplitterValue;
-                break;
-            case DockState.DockRight:
-                result.Location.X += result.Size.X * (1 - DockPanel.DefaultSplitterValue);
-                result.Size.X *= DockPanel.DefaultSplitterValue;
-                break;
-            }
-            return result;
-        }
-
-        private void CalculateDragOffset(Float2 mouseScreenPosition)
-        {
-            var baseWinPos = _toMove.Window.Window.Position;
-            _dragOffset = mouseScreenPosition - baseWinPos;
-        }
-
-        private void UpdateRects()
-        {
-            // Cache mouse position
-            _mouse = Platform.MousePosition;
-
-            // Check intersection with any dock panel
-            var uiMouse = _mouse;
-            _toDock = _toMove.MasterPanel.HitTest(ref uiMouse, _toMove);
-
-            // Check dock state to use
-            bool showProxyHints = _toDock != null;
-            bool showBorderHints = showProxyHints;
-            bool showCenterHint = showProxyHints;
-            if (showProxyHints)
-            {
-                // If moved window has not only tabs but also child panels disable docking as tab
-                if (_toMove.ChildPanelsCount > 0)
-                    showCenterHint = false;
-
-                // Disable docking windows with one or more dock panels inside
-                if (_toMove.ChildPanelsCount > 0)
-                    showBorderHints = false;
-
-                // Get dock area
-                _rectDock = _toDock.DockAreaBounds;
-
-                // Cache dock rectangles
-                var size = _rectDock.Size;
-                var offset = _rectDock.Location;
-                var borderMargin = 4.0f;
-                var hintWindowsSize = Proxy.HintWindowsSize * Platform.DpiScale;
-                var hintWindowsSize2 = hintWindowsSize * 0.5f;
-                var centerX = size.X * 0.5f;
-                var centerY = size.Y * 0.5f;
-                _rUpper = new Rectangle(centerX - hintWindowsSize2, borderMargin, hintWindowsSize, hintWindowsSize) + offset;
-                _rBottom = new Rectangle(centerX - hintWindowsSize2, size.Y - hintWindowsSize - borderMargin, hintWindowsSize, hintWindowsSize) + offset;
-                _rLeft = new Rectangle(borderMargin, centerY - hintWindowsSize2, hintWindowsSize, hintWindowsSize) + offset;
-                _rRight = new Rectangle(size.X - hintWindowsSize - borderMargin, centerY - hintWindowsSize2, hintWindowsSize, hintWindowsSize) + offset;
-                _rCenter = new Rectangle(centerX - hintWindowsSize2, centerY - hintWindowsSize2, hintWindowsSize, hintWindowsSize) + offset;
-
-                // Hit test
-                DockState toSet = DockState.Float;
-                if (showBorderHints)
-                {
-                    if (_rUpper.Contains(_mouse))
-                        toSet = DockState.DockTop;
-                    else if (_rBottom.Contains(_mouse))
-                        toSet = DockState.DockBottom;
-                    else if (_rLeft.Contains(_mouse))
-                        toSet = DockState.DockLeft;
-                    else if (_rRight.Contains(_mouse))
-                        toSet = DockState.DockRight;
-                }
-                if (showCenterHint && _rCenter.Contains(_mouse))
-                    toSet = DockState.DockFill;
-                _toSet = toSet;
-
-                // Show proxy hint windows
-                Proxy.Down.Position = _rBottom.Location;
-                Proxy.Left.Position = _rLeft.Location;
-                Proxy.Right.Position = _rRight.Location;
-                Proxy.Up.Position = _rUpper.Location;
-                Proxy.Center.Position = _rCenter.Location;
-            }
-            else
-            {
-                _toSet = DockState.Float;
-            }
-
-            // Update proxy hint windows visibility
-            Proxy.Down.IsVisible = showProxyHints & showBorderHints;
-            Proxy.Left.IsVisible = showProxyHints & showBorderHints;
-            Proxy.Right.IsVisible = showProxyHints & showBorderHints;
-            Proxy.Up.IsVisible = showProxyHints & showBorderHints;
-            Proxy.Center.IsVisible = showProxyHints & showCenterHint;
-
-            // Calculate proxy/dock/window rectangles
-            if (_toDock == null)
-            {
-                // Floating window over nothing
-                _rectWindow = new Rectangle(_mouse - _dragOffset, _defaultWindowSize);
-            }
-            else
-            {
-                if (_toSet == DockState.Float)
-                {
-                    // Floating window over dock panel
-                    _rectWindow = new Rectangle(_mouse - _dragOffset, _defaultWindowSize);
-                }
-                else
-                {
-                    // Use only part of the dock panel to show hint
-                    _rectWindow = CalculateDockRect(_toSet, ref _rectDock);
-                }
-            }
-
-            // Update proxy window
-            Proxy.Window.ClientBounds = _rectWindow;
-        }
-
-        private void OnMouseUp(ref Float2 location, MouseButton button, ref bool handled)
-        {
-            if (button == MouseButton.Left)
-            {
-                Dispose();
-            }
-        }
-
-        private void OnMouseMove(ref Float2 mousePos)
-        {
-            // Recalculate the drag offset because the current mouse screen position was invalid when we initialized the window
-            if (_lateDragOffsetUpdate)
-            {
-                // Calculate dragging offset and move window to the destination position
-                CalculateDragOffset(mousePos);
-
-                // Reset state
-                _lateDragOffsetUpdate = false;
-            }
-
-            UpdateRects();
-        }
-
-        private void OnLostFocus()
-        {
-            Dispose();
-        }
-
-        /// <summary>
-        /// Contains helper proxy windows shared across docking panels. They are used to visualize docking window locations.
-        /// </summary>
-        public static class Proxy
-        {
-            /// <summary>
-            /// The drag proxy window.
-            /// </summary>
-            public static Window Window;
-
-            /// <summary>
-            /// The left hint proxy window.
-            /// </summary>
-            public static Window Left;
-
-            /// <summary>
-            /// The right hint proxy window.
-            /// </summary>
-            public static Window Right;
-
-            /// <summary>
-            /// The up hint proxy window.
-            /// </summary>
-            public static Window Up;
-
-            /// <summary>
-            /// The down hint proxy window.
-            /// </summary>
-            public static Window Down;
-
-            /// <summary>
-            /// The center hint proxy window.
-            /// </summary>
-            public static Window Center;
-
-            /// <summary>
-            /// The hint windows size.
-            /// </summary>
-            public const float HintWindowsSize = 32.0f;
-
-            /// <summary>
-            /// Initializes the hit proxy windows. Those windows are used to indicate drag target areas (left, right, top, bottom, etc.).
-            /// </summary>
-            public static void InitHitProxy()
-            {
-                CreateProxy(ref Left, "DockHint.Left");
-                CreateProxy(ref Right, "DockHint.Right");
-                CreateProxy(ref Up, "DockHint.Up");
-                CreateProxy(ref Down, "DockHint.Down");
-                CreateProxy(ref Center, "DockHint.Center");
-            }
-
-            /// <summary>
-            /// Initializes the hint window.
-            /// </summary>
-            /// <param name="initSize">Initial size of the proxy window.</param>
-            public static void Init(ref Float2 initSize)
-            {
-                if (Window == null)
-                {
-                    var settings = CreateWindowSettings.Default;
-                    settings.Title = "DockHint.Window";
-                    settings.Size = initSize;
-                    settings.AllowInput = true;
-                    settings.AllowMaximize = false;
-                    settings.AllowMinimize = false;
-                    settings.HasBorder = false;
-                    settings.HasSizingFrame = false;
-                    settings.IsRegularWindow = false;
-                    settings.SupportsTransparency = true;
-                    settings.ShowInTaskbar = false;
-                    settings.ShowAfterFirstPaint = false;
-                    settings.IsTopmost = true;
-
-                    Window = Platform.CreateWindow(ref settings);
-                    Window.Opacity = 0.6f;
-                    Window.GUI.BackgroundColor = Style.Current.Selection;
-                    Window.GUI.AddChild<DragVisuals>();
-                }
-                else
-                {
-                    // Resize proxy
-                    Window.ClientSize = initSize;
-                }
-
-                InitHitProxy();
-            }
-
-            private sealed class DragVisuals : Control
-            {
-                public DragVisuals()
-                {
-                    AnchorPreset = AnchorPresets.StretchAll;
-                    Offsets = Margin.Zero;
-                }
-
-                public override void Draw()
-                {
-                    Render2D.DrawRectangle(new Rectangle(Float2.Zero, Size), Style.Current.SelectionBorder);
-                }
-            }
-
-            private static void CreateProxy(ref Window win, string name)
-            {
-                if (win != null)
-                    return;
-
-                var settings = CreateWindowSettings.Default;
-                settings.Title = name;
-                settings.Size = new Float2(HintWindowsSize * Platform.DpiScale);
-                settings.AllowInput = false;
-                settings.AllowMaximize = false;
-                settings.AllowMinimize = false;
-                settings.HasBorder = false;
-                settings.HasSizingFrame = false;
-                settings.IsRegularWindow = false;
-                settings.SupportsTransparency = true;
-                settings.ShowInTaskbar = false;
-                settings.ActivateWhenFirstShown = false;
-                settings.IsTopmost = true;
-                settings.ShowAfterFirstPaint = false;
-
-                win = Platform.CreateWindow(ref settings);
-                win.Opacity = 0.6f;
-                win.GUI.BackgroundColor = Style.Current.Selection;
-                win.GUI.AddChild<DragVisuals>();
-            }
-
-            /// <summary>
-            /// Hides proxy windows.
-            /// </summary>
-            public static void Hide()
-            {
-                HideProxy(ref Window);
-                HideProxy(ref Left);
-                HideProxy(ref Right);
-                HideProxy(ref Up);
-                HideProxy(ref Down);
-                HideProxy(ref Center);
-            }
-
-            private static void HideProxy(ref Window win)
-            {
-                if (win)
-                {
-                    win.Hide();
-                }
-            }
-
-            /// <summary>
-            /// Releases proxy data and windows.
-            /// </summary>
-            public static void Dispose()
-            {
-                DisposeProxy(ref Window);
-                DisposeProxy(ref Left);
-                DisposeProxy(ref Right);
-                DisposeProxy(ref Up);
-                DisposeProxy(ref Down);
-                DisposeProxy(ref Center);
-            }
-
-            private static void DisposeProxy(ref Window win)
-            {
-                if (win)
-                {
-                    win.Close(ClosingReason.User);
-                    win = null;
-                }
-            }
-        }
-    }
-}

Source/Editor/GUI/Docking/DockPanelProxy.cs

@@ -19,11 +19,7 @@ namespace FlaxEditor.GUI.Docking
         private float _tabHeight = Editor.Instance.Options.Options.Interface.TabHeight;
         private bool _useMinimumTabWidth = Editor.Instance.Options.Options.Interface.UseMinimumTabWidth;
         private float _minimumTabWidth = Editor.Instance.Options.Options.Interface.MinimumTabWidth;
-#if PLATFORM_WINDOWS
-        private readonly bool _hideTabForSingleTab = Editor.Instance.Options.Options.Interface.HideSingleTabWindowTabBars;
-#else
-        private readonly bool _hideTabForSingleTab = false;
-#endif
+        private readonly bool _hideTabForSingleTab = Utilities.Utils.HideSingleTabWindowTabBars();
 
         /// <summary>
         /// The is mouse down flag (left button).
@@ -54,6 +50,11 @@ namespace FlaxEditor.GUI.Docking
         /// The mouse position.
         /// </summary>
         public Float2 MousePosition = Float2.Minimum;
+        
+        /// <summary>
+        /// The mouse position.
+        /// </summary>
+        public Float2 MouseStartPosition = Float2.Minimum;
 
         /// <summary>
         /// The start drag asynchronous window.
@@ -70,8 +71,6 @@ namespace FlaxEditor.GUI.Docking
         internal DockPanelProxy(DockPanel panel)
         : base(0, 0, 64, 64)
         {
-            AutoFocus = false;
-
             _panel = panel;
             AnchorPreset = AnchorPresets.StretchAll;
             Offsets = Margin.Zero;
@@ -198,7 +197,7 @@ namespace FlaxEditor.GUI.Docking
                 if (_panel.ChildPanelsCount == 0 && _panel.TabsCount == 1 && _panel.IsFloating)
                 {
                     // Create docking hint window but in an async manner
-                    DockHintWindow.Create(_panel as FloatWindowDockPanel);
+                    WindowDragHelper.StartDragging(_panel as FloatWindowDockPanel);
                 }
                 else
                 {
@@ -209,7 +208,7 @@ namespace FlaxEditor.GUI.Docking
                     _panel.SelectTab(index - 1);
 
                     // Create docking hint window
-                    DockHintWindow.Create(win);
+                    WindowDragHelper.StartDragging(win, _panel.RootWindow.Window);
                 }
             }
         }
@@ -395,6 +394,7 @@ namespace FlaxEditor.GUI.Docking
             if (IsSingleFloatingWindow)
                 return base.OnMouseDown(location, button);
             MouseDownWindow = GetTabAtPos(location, out IsMouseDownOverCross);
+            MouseStartPosition = location;
 
             // Check buttons
             if (button == MouseButton.Left)
@@ -481,6 +481,20 @@ namespace FlaxEditor.GUI.Docking
                         StartDrag(MouseDownWindow);
                     MouseDownWindow = null;
                 }
+                // Check if single tab is tried to be moved
+                else if (MouseDownWindow != null && _panel.TabsCount <= 1)
+                {
+                    if ((MousePosition - MouseStartPosition).Length > 3)
+                    {
+                        // Clear flag
+                        IsMouseLeftButtonDown = false;
+
+                        // Check tab under the mouse
+                        if (!IsMouseDownOverCross && MouseDownWindow != null)
+                            StartDrag(MouseDownWindow);
+                        MouseDownWindow = null;
+                    }
+                }
                 // Check if has more than one tab to change order
                 else if (MouseDownWindow != null && _panel.TabsCount > 1)
                 {

Source/Editor/GUI/Docking/DockWindow.cs

@@ -182,6 +182,25 @@ namespace FlaxEditor.GUI.Docking
         /// <param name="size">Window size, set <see cref="Float2.Zero"/> to use default.</param>
         /// <param name="position">Window location.</param>
         public void ShowFloating(Float2 location, Float2 size, WindowStartPosition position = WindowStartPosition.CenterParent)
+        {
+            CreateFloating(location, size, position, true);
+        }
+
+        /// <summary>
+        /// Creates the window in a floating state.
+        /// </summary>
+        public void CreateFloating()
+        {
+            CreateFloating(Float2.Zero, Float2.Zero);
+        }
+        /// <summary>
+        /// Creates the window in a floating state.
+        /// </summary>
+        /// <param name="location">Window location.</param>
+        /// <param name="size">Window size, set <see cref="Float2.Zero"/> to use default.</param>
+        /// <param name="position">Window location.</param>
+        /// <param name="showWindow">Window visibility.</param>
+        public void CreateFloating(Float2 location, Float2 size, WindowStartPosition position = WindowStartPosition.CenterParent, bool showWindow = false)
         {
             Undock();
 
@@ -199,14 +218,17 @@ namespace FlaxEditor.GUI.Docking
             windowGUI.UnlockChildrenRecursive();
             windowGUI.PerformLayout();
 
-            // Show
-            window.Show();
-            window.BringToFront();
-            window.Focus();
-            OnShow();
+            if (showWindow)
+            {
+                // Show
+                window.Show();
+                window.BringToFront();
+                window.Focus();
+                OnShow();
 
-            // Perform layout again
-            windowGUI.PerformLayout();
+                // Perform layout again
+                windowGUI.PerformLayout();
+            }
         }
 
         /// <summary>

Source/Editor/GUI/Docking/FloatWindowDockPanel.cs

@@ -11,6 +11,42 @@ namespace FlaxEditor.GUI.Docking
     /// <seealso cref="DockPanel" />
     public class FloatWindowDockPanel : DockPanel
     {
+        private class FloatWindowDecorations : WindowDecorations
+        {
+            private FloatWindowDockPanel _panel;
+            
+            public FloatWindowDecorations(FloatWindowDockPanel panel)
+            : base(panel.RootWindow)
+            {
+                _panel = panel;
+            }
+            
+            /// <inheritdoc />
+            public override bool OnMouseDown(Float2 location, MouseButton button)
+            {
+                if (Title.Bounds.Contains(location) && button == MouseButton.Left)
+                {
+                    _panel.BeginDrag();
+                    return true;
+                }
+                return base.OnMouseDown(location, button);
+            }
+
+#if !PLATFORM_WINDOWS
+            /// <inheritdoc />
+            protected override WindowHitCodes OnHitTest(ref Float2 mouse)
+            {
+                var hit = base.OnHitTest(ref mouse);
+                if (hit == WindowHitCodes.Caption)
+                {
+                    // Override the system behaviour when interacting with the caption area
+                    hit = WindowHitCodes.Client;
+                }
+                return hit;
+            }
+#endif
+        }
+
         private MasterDockPanel _masterPanel;
         private WindowRootControl _window;
 
@@ -40,6 +76,26 @@ namespace FlaxEditor.GUI.Docking
             Parent = window;
             _window.Window.Closing += OnClosing;
             _window.Window.LeftButtonHit += OnLeftButtonHit;
+            
+            if (Utilities.Utils.UseCustomWindowDecorations())
+            {
+                var decorations = Parent.AddChild(new FloatWindowDecorations(this));
+                decorations.SetAnchorPreset(AnchorPresets.HorizontalStretchTop, false);
+            }
+        }
+        
+        /// <inheritdoc />
+        protected override void PerformLayoutBeforeChildren()
+        {
+            base.PerformLayoutBeforeChildren();
+            
+            var decorations = Parent.GetChild<FloatWindowDecorations>();
+            if (decorations != null)
+            {
+                // Apply offset for the title bar
+                foreach (var child in Children)
+                    child.Bounds = child.Bounds with { Y = decorations.Height, Height = Parent.Height - decorations.Height };
+            }
         }
 
         /// <summary>
@@ -52,7 +108,7 @@ namespace FlaxEditor.GUI.Docking
                 return;
 
             // Create docking hint window
-            DockHintWindow.Create(this);
+            WindowDragHelper.StartDragging(this);
         }
 
         /// <summary>
@@ -71,22 +127,28 @@ namespace FlaxEditor.GUI.Docking
             settings.Title = title;
             settings.Size = size;
             settings.Position = location;
-            settings.MinimumSize = new Float2(1);
+            settings.MinimumSize = new Float2(200, 150);
             settings.MaximumSize = Float2.Zero; // Unlimited size
             settings.Fullscreen = false;
             settings.HasBorder = true;
-            settings.SupportsTransparency = false;
+            settings.SupportsTransparency = true;
             settings.ActivateWhenFirstShown = true;
             settings.AllowInput = true;
             settings.AllowMinimize = true;
             settings.AllowMaximize = true;
             settings.AllowDragAndDrop = true;
             settings.IsTopmost = false;
-            settings.IsRegularWindow = true;
+            settings.Type = WindowType.Regular;
             settings.HasSizingFrame = true;
             settings.ShowAfterFirstPaint = false;
             settings.ShowInTaskbar = true;
             settings.StartPosition = startPosition;
+            
+            if (Utilities.Utils.UseCustomWindowDecorations())
+            {
+                settings.HasBorder = false;
+                //settings.HasSizingFrame = false;
+            }
 
             // Create window
             return Platform.CreateWindow(ref settings);

Source/Editor/GUI/Docking/MasterDockPanel.cs

@@ -81,7 +81,6 @@ namespace FlaxEditor.GUI.Docking
         public DockPanel HitTest(ref Float2 position, FloatWindowDockPanel excluded)
         {
             // Check all floating windows
-            // TODO: gather windows order and take it into account when performing test
             for (int i = 0; i < FloatingPanels.Count; i++)
             {
                 var win = FloatingPanels[i];
@@ -94,9 +93,44 @@ namespace FlaxEditor.GUI.Docking
             }
 
             // Base
+            //if (!Root?.RootWindow.Window.IsFocused ?? false)
+            //    return null;
             return base.HitTest(ref position);
         }
 
+        /// <summary>
+        /// Performs hit test over dock panel.
+        /// </summary>
+        /// <param name="position">Window space position to test.</param>
+        /// <param name="excluded">Floating window to omit during searching (and all docked to that one).</param>
+        /// <param name="hitResults">Results of the hit test</param>
+        /// <returns>True if any dock panels were hit, otherwise false.</returns>
+        public bool HitTest(ref Float2 position, FloatWindowDockPanel excluded, out DockPanel[] hitResults)
+        {
+            // Check all floating windows
+            List<DockPanel> results = new(FloatingPanels.Count);
+            for (int i = 0; i < FloatingPanels.Count; i++)
+            {
+                var win = FloatingPanels[i];
+                if (win.Visible && win != excluded)
+                {
+                    var result = win.HitTest(ref position);
+                    if (result != null)
+                        results.Add(result);
+                }
+            }
+
+            // Base
+            //if (!Root?.RootWindow.Window.IsFocused ?? false)
+            //    return null;
+            var baseResult = base.HitTest(ref position);
+            if (baseResult != null)
+                results.Add(baseResult);
+
+            hitResults = results.ToArray();
+            return hitResults.Length > 0;
+        }
+
         internal void LinkWindow(DockWindow window)
         {
             // Add to the windows list

Source/Editor/GUI/Docking/WindowDragHelper.cs

@@ -0,0 +1,458 @@
+// Copyright (c) Wojciech Figat. All rights reserved.
+
+using System;
+using FlaxEngine;
+using FlaxEngine.GUI;
+
+namespace FlaxEditor.GUI.Docking
+{
+    /// <summary>
+    /// Helper class used to handle docking windows dragging and docking.
+    /// </summary>
+    public class WindowDragHelper
+    {
+        private FloatWindowDockPanel _toMove;
+
+        private Float2 _dragOffset;
+        private Rectangle _rectDock;
+        private Float2 _mouse;
+        private DockState _toSet;
+        private DockPanel _toDock;
+        private Window _dragSourceWindow;
+
+        private Rectangle _rLeft, _rRight, _rBottom, _rUpper, _rCenter;
+        private Control _dockHintDown, _dockHintUp, _dockHintLeft, _dockHintRight, _dockHintCenter;
+
+        /// <summary>
+        /// The hint control size.
+        /// </summary>
+        public const float HintControlSize = 32.0f;
+
+        /// <summary>
+        /// The opacity of the dragged window when hint controls are shown.
+        /// </summary>
+        public const float DragWindowOpacity = 0.4f;
+        
+        /// <summary>
+        /// Returns true if any windows are being dragged.
+        /// </summary>
+        public static bool IsDragActive { get; private set; }
+
+        private WindowDragHelper(FloatWindowDockPanel toMove, Window dragSourceWindow)
+        {
+            IsDragActive = true;
+            _toMove = toMove;
+            _toSet = DockState.Float;
+            var window = toMove.Window.Window;
+
+            // Bind events
+            FlaxEngine.Scripting.Update += OnUpdate;
+            window.MouseUp += OnMouseUp;
+            
+            // Update rectangles
+            UpdateRects(Platform.MousePosition);
+            
+            // Ensure the dragged window stays on top of every other window
+            window.IsAlwaysOnTop = true;
+
+            _dragSourceWindow = dragSourceWindow;
+            if (_dragSourceWindow != null) // Detaching a tab from existing window
+            {
+                _dragOffset = new Float2(window.Size.X / 2, 10.0f);
+                
+                _dragSourceWindow.MouseUp += OnMouseUp; // The mouse up event is sent to the source window on Windows
+
+                // TODO: when detaching tab in floating window (not main window), the drag source window is still main window?
+                var dragSourceWindowWayland = toMove.MasterPanel?.RootWindow.Window ?? Editor.Instance.Windows.MainWindow;
+                window.DoDragDrop(window.Title, _dragOffset, dragSourceWindowWayland);
+            }
+            else
+            {
+                _dragOffset = window.MousePosition;
+                window.DoDragDrop(window.Title, _dragOffset, window);
+            }
+        }
+
+        /// <summary>
+        /// Releases unmanaged and - optionally - managed resources.
+        /// </summary>
+        public void Dispose()
+        {
+            IsDragActive = false;
+            var window = _toMove?.Window?.Window;
+
+            // Unbind events
+            FlaxEngine.Scripting.Update -= OnUpdate;
+            if (window != null)
+                window.MouseUp -= OnMouseUp;
+            if (_dragSourceWindow != null)
+                _dragSourceWindow.MouseUp -= OnMouseUp;
+
+            RemoveDockHints();
+
+            if (_toMove == null)
+                return;
+
+            if (window != null)
+            {
+                window.Opacity = 1.0f;
+                window.IsAlwaysOnTop = false;
+                window.BringToFront();
+            }
+
+            // Check if window won't be docked
+            if (_toSet == DockState.Float)
+            {
+                if (window == null)
+                    return;
+
+                // Show base window
+                window.Show();
+            }
+            else
+            {
+                bool hasNoChildPanels = _toMove.ChildPanelsCount == 0;
+
+                // Check if window has only single tab
+                if (hasNoChildPanels && _toMove.TabsCount == 1)
+                {
+                    // Dock window
+                    _toMove.GetTab(0).Show(_toSet, _toDock);
+                }
+                // Check if dock as tab and has no child panels
+                else if (hasNoChildPanels && _toSet == DockState.DockFill)
+                {
+                    // Dock all tabs
+                    while (_toMove.TabsCount > 0)
+                    {
+                        _toMove.GetTab(0).Show(DockState.DockFill, _toDock);
+                    }
+                }
+                else
+                {
+                    var selectedTab = _toMove.SelectedTab;
+
+                    // Dock the first tab into the target location
+                    if (_toMove.TabsCount > 0)
+                    {
+                        var firstTab = _toMove.GetTab(0);
+                        firstTab.Show(_toSet, _toDock);
+
+                        // Dock rest of the tabs
+                        while (_toMove.TabsCount > 0)
+                        {
+                            _toMove.GetTab(0).Show(DockState.DockFill, firstTab);
+                        }
+                    }
+
+                    // Keep selected tab being selected
+                    selectedTab?.SelectTab();
+                }
+
+                // Focus target window
+                _toDock.Root.Focus();
+            }
+
+            _toMove = null;
+        }
+
+        /// <summary>
+        /// Start dragging a floating dock panel.
+        /// </summary>
+        /// <param name="toMove">Floating dock panel to move.</param>
+        /// <returns>The window drag helper object.</returns>
+        public static WindowDragHelper StartDragging(FloatWindowDockPanel toMove)
+        {
+            if (toMove == null)
+                throw new ArgumentNullException();
+
+            return new WindowDragHelper(toMove, null);
+        }
+
+        /// <summary>
+        /// Start dragging a docked panel into a floating window.
+        /// </summary>
+        /// <param name="toMove">Dock window to move.</param>
+        /// <param name="dragSourceWindow">The window where dragging started from.</param>
+        /// <returns>The window drag helper object.</returns>
+        public static WindowDragHelper StartDragging(DockWindow toMove, Window dragSourceWindow)
+        {
+            if (toMove == null)
+                throw new ArgumentNullException();
+
+            // Create floating window
+            toMove.CreateFloating();
+
+            // Get floating panel
+            var window = (WindowRootControl)toMove.Root;
+            var floatingPanelToMove = window.GetChild(0) as FloatWindowDockPanel;
+
+            return new WindowDragHelper(floatingPanelToMove, dragSourceWindow);
+        }
+
+        private sealed class DragVisuals : Control
+        {
+            public DragVisuals()
+            {
+                AnchorPreset = AnchorPresets.StretchAll;
+                Offsets = Margin.Zero;
+            }
+
+            public override void Draw()
+            {
+                base.Draw();
+                Render2D.DrawRectangle(new Rectangle(Float2.Zero, Size), Style.Current.SelectionBorder);
+            }
+        }
+
+        private void AddDockHints()
+        {
+            if (_toDock == null)
+                return;
+
+            if (_toDock.RootWindow.Window != _dragSourceWindow)
+                _toDock.RootWindow.Window.MouseUp += OnMouseUp;
+
+            _dockHintDown = AddHintControl(new Float2(0.5f, 1));
+            _dockHintUp = AddHintControl(new Float2(0.5f, 0));
+            _dockHintLeft = AddHintControl(new Float2(0, 0.5f));
+            _dockHintRight = AddHintControl(new Float2(1, 0.5f));
+            _dockHintCenter = AddHintControl(new Float2(0.5f, 0.5f));
+
+            Control AddHintControl(Float2 pivot)
+            {
+                DragVisuals hintControl = _toDock.AddChild<DragVisuals>();
+                hintControl.Size = new Float2(HintControlSize);
+                hintControl.BackgroundColor = Style.Current.Selection.AlphaMultiplied(0.6f);
+                hintControl.Pivot = pivot;
+                hintControl.PivotRelative = true;
+                return hintControl;
+            }
+        }
+        
+        private void RemoveDockHints()
+        {
+            if (_toDock == null)
+                return;
+
+            if (_toDock.RootWindow.Window != _dragSourceWindow)
+                _toDock.RootWindow.Window.MouseUp -= OnMouseUp;
+
+            _dockHintDown?.Parent.RemoveChild(_dockHintDown);
+            _dockHintUp?.Parent.RemoveChild(_dockHintUp);
+            _dockHintLeft?.Parent.RemoveChild(_dockHintLeft);
+            _dockHintRight?.Parent.RemoveChild(_dockHintRight);
+            _dockHintCenter?.Parent.RemoveChild(_dockHintCenter);
+            _dockHintDown = _dockHintUp = _dockHintLeft = _dockHintRight = _dockHintCenter = null;
+        }
+
+        private void UpdateRects(Float2 mousePos)
+        {
+            // Cache mouse position
+            _mouse = mousePos;
+
+            // Check intersection with any dock panel
+            DockPanel dockPanel = null;
+            if (_toMove.MasterPanel.HitTest(ref _mouse, _toMove, out var hitResults))
+            {
+                dockPanel = hitResults[0];
+
+                // Prefer panel which currently has focus
+                foreach (var hit in hitResults)
+                {
+                    if (hit.RootWindow.Window.IsFocused)
+                    {
+                        dockPanel = hit;
+                        break;
+                    }
+                }
+
+                // Prefer panel in the same window we hit earlier
+                if (dockPanel?.RootWindow != _toDock?.RootWindow)
+                {
+                    foreach (var hit in hitResults)
+                    {
+                        if (hit.RootWindow == _toDock?.RootWindow)
+                        {
+                            dockPanel = _toDock;
+                            break;
+                        }
+                    }
+                }
+            }
+            
+            if (dockPanel != _toDock)
+            {
+                RemoveDockHints();
+                _toDock = dockPanel;
+                AddDockHints();
+
+                // Make sure the all the dock hint areas are not under other windows
+                _toDock?.RootWindow.Window.BringToFront();
+                //_toDock?.RootWindow.Window.Focus();
+
+                // Make the dragged window transparent when dock hints are visible
+                _toMove.Window.Window.Opacity = _toDock == null ? 1.0f : DragWindowOpacity;
+            }
+            
+            // Check dock state to use
+            bool showProxyHints = _toDock != null;
+            bool showBorderHints = showProxyHints;
+            bool showCenterHint = showProxyHints;
+            Control hoveredHintControl = null;
+            Float2 hoveredSizeOverride = Float2.Zero;
+            if (showProxyHints)
+            {
+                // If moved window has not only tabs but also child panels disable docking as tab
+                if (_toMove.ChildPanelsCount > 0)
+                    showCenterHint = false;
+
+                // Disable docking windows with one or more dock panels inside
+                if (_toMove.ChildPanelsCount > 0)
+                    showBorderHints = false;
+
+                // Get dock area
+                _rectDock = _toDock.DockAreaBounds;
+
+                // Cache dock rectangles
+                var size = _rectDock.Size / Platform.DpiScale;
+                var offset = _toDock.PointFromScreen(_rectDock.Location);
+                var borderMargin = 4.0f;
+                var hintWindowsSize = HintControlSize;
+                var hintWindowsSize2 = hintWindowsSize * 0.5f;
+                var hintPreviewSize = new Float2(Math.Max(HintControlSize * 2, size.X * 0.5f), Math.Max(HintControlSize * 2, size.Y * 0.5f));
+                var centerX = size.X * 0.5f;
+                var centerY = size.Y * 0.5f;
+                _rUpper = new Rectangle(centerX - hintWindowsSize2, borderMargin, hintWindowsSize, hintWindowsSize) + offset;
+                _rBottom = new Rectangle(centerX - hintWindowsSize2, size.Y - hintWindowsSize - borderMargin, hintWindowsSize, hintWindowsSize) + offset;
+                _rLeft = new Rectangle(borderMargin, centerY - hintWindowsSize2, hintWindowsSize, hintWindowsSize) + offset;
+                _rRight = new Rectangle(size.X - hintWindowsSize - borderMargin, centerY - hintWindowsSize2, hintWindowsSize, hintWindowsSize) + offset;
+                _rCenter = new Rectangle(centerX - hintWindowsSize2, centerY - hintWindowsSize2, hintWindowsSize, hintWindowsSize) + offset;
+
+                // Hit test, and calculate the approximation for filled area when hovered over the hint
+                DockState toSet = DockState.Float;
+                if (showBorderHints)
+                {
+                    if (_rUpper.Contains(_toDock.PointFromScreen(_mouse)))
+                    {
+                        toSet = DockState.DockTop;
+                        hoveredHintControl = _dockHintUp;
+                        hoveredSizeOverride = new Float2(size.X, hintPreviewSize.Y);
+                    }
+                    else if (_rBottom.Contains(_toDock.PointFromScreen(_mouse)))
+                    {
+                        toSet = DockState.DockBottom;
+                        hoveredHintControl = _dockHintDown;
+                        hoveredSizeOverride = new Float2(size.X, hintPreviewSize.Y);
+                    }
+                    else if (_rLeft.Contains(_toDock.PointFromScreen(_mouse)))
+                    {
+                        toSet = DockState.DockLeft;
+                        hoveredHintControl = _dockHintLeft;
+                        hoveredSizeOverride = new Float2(hintPreviewSize.X, size.Y);
+                    }
+                    else if (_rRight.Contains(_toDock.PointFromScreen(_mouse)))
+                    {
+                        toSet = DockState.DockRight;
+                        hoveredHintControl = _dockHintRight;
+                        hoveredSizeOverride = new Float2(hintPreviewSize.X, size.Y);
+                    }
+                }
+                if (showCenterHint && _rCenter.Contains(_toDock.PointFromScreen(_mouse)))
+                {
+                    toSet = DockState.DockFill;
+                    hoveredHintControl = _dockHintCenter;
+                    hoveredSizeOverride = new Float2(size.X, size.Y);
+                }
+
+                _toSet = toSet;
+            }
+            else
+            {
+                _toSet = DockState.Float;
+            }
+            
+            // Update sizes and opacity of hint controls
+            if (_toDock != null)
+            {
+                if (hoveredHintControl != _dockHintDown)
+                {
+                    _dockHintDown.Size = new Float2(HintControlSize);
+                    _dockHintDown.BackgroundColor = Style.Current.Selection.AlphaMultiplied(0.6f);
+                }
+                if (hoveredHintControl != _dockHintLeft)
+                {
+                    _dockHintLeft.Size = new Float2(HintControlSize);
+                    _dockHintLeft.BackgroundColor = Style.Current.Selection.AlphaMultiplied(0.6f);
+                }
+                if (hoveredHintControl != _dockHintRight)
+                {
+                    _dockHintRight.Size = new Float2(HintControlSize);
+                    _dockHintRight.BackgroundColor = Style.Current.Selection.AlphaMultiplied(0.6f);
+                }
+                if (hoveredHintControl != _dockHintUp)
+                {
+                    _dockHintUp.Size = new Float2(HintControlSize);
+                    _dockHintUp.BackgroundColor = Style.Current.Selection.AlphaMultiplied(0.6f);
+                }
+                if (hoveredHintControl != _dockHintCenter)
+                {
+                    _dockHintCenter.Size = new Float2(HintControlSize);
+                    _dockHintCenter.BackgroundColor = Style.Current.Selection.AlphaMultiplied(0.6f);
+                }
+
+                if (_toSet != DockState.Float)
+                {
+                    if (hoveredHintControl != null)
+                    {
+                        hoveredHintControl.BackgroundColor = Style.Current.Selection.AlphaMultiplied(1.0f);
+                        hoveredHintControl.Size = hoveredSizeOverride;
+                    }
+                }
+            }
+
+            // Update hint controls visibility and location
+            if (showProxyHints)
+            {
+                if (hoveredHintControl != _dockHintDown)
+                    _dockHintDown.Location = _rBottom.Location;
+                if (hoveredHintControl != _dockHintLeft)
+                    _dockHintLeft.Location = _rLeft.Location;
+                if (hoveredHintControl != _dockHintRight)
+                    _dockHintRight.Location = _rRight.Location;
+                if (hoveredHintControl != _dockHintUp)
+                    _dockHintUp.Location = _rUpper.Location;
+                if (hoveredHintControl != _dockHintCenter)
+                    _dockHintCenter.Location = _rCenter.Location;
+                
+                _dockHintDown.Visible = showProxyHints & showBorderHints;
+                _dockHintLeft.Visible = showProxyHints & showBorderHints;
+                _dockHintRight.Visible = showProxyHints & showBorderHints;
+                _dockHintUp.Visible = showProxyHints & showBorderHints;
+                _dockHintCenter.Visible = showProxyHints & showCenterHint;
+            }
+        }
+
+        private void OnMouseUp(ref Float2 location, MouseButton button, ref bool handled)
+        {
+            if (button == MouseButton.Left)
+                Dispose();
+        }
+
+        private void OnUpdate()
+        {
+            var mousePos = Platform.MousePosition;
+
+            if (_mouse != mousePos)
+                OnMouseMove(mousePos);
+        }
+        
+        private void OnMouseMove(Float2 mousePos)
+        {
+            if (_dragSourceWindow != null)
+                _toMove.Window.Window.Position = mousePos - _dragOffset;
+
+            UpdateRects(mousePos);
+        }
+    }
+}

Source/Editor/GUI/Input/ColorValueBox.cs

@@ -129,11 +129,39 @@ namespace FlaxEditor.GUI.Input
         {
             base.Draw();
 
-            var style = Style.Current;
-            var r = new Rectangle(0, 0, Width, Height);
+            bool isTransparent = _value.A < 1;
 
-            Render2D.FillRectangle(r, _value);
-            Render2D.DrawRectangle(r, IsMouseOver || IsNavFocused ? style.BackgroundSelected : Color.Black);
+            var style = Style.Current;
+            var fullRect = new Rectangle(0, 0, Width, Height);
+            var colorRect = new Rectangle(0, 0, isTransparent ? Width * 0.7f : Width, Height);
+
+            if (isTransparent)
+            {
+                var alphaRect = new Rectangle(colorRect.Right, 0, Width - colorRect.Right, Height);
+
+                // Draw checkerboard pattern to part of the color value box
+                Render2D.FillRectangle(alphaRect, Color.White);
+                var smallRectSize = 7.9f;
+                var numHor = Mathf.CeilToInt(alphaRect.Width / smallRectSize);
+                var numVer = Mathf.CeilToInt(alphaRect.Height / smallRectSize);
+                for (int i = 0; i < numHor; i++)
+                {
+                    for (int j = 0; j < numVer; j++)
+                    {
+                        if ((i + j) % 2 == 0)
+                        {
+                            var rect = new Rectangle(alphaRect.X + smallRectSize * i, alphaRect.Y + smallRectSize * j, new Float2(smallRectSize));
+                            Render2D.PushClip(alphaRect);
+                            Render2D.FillRectangle(rect, Color.Gray);
+                            Render2D.PopClip();
+                        }
+                    }
+                }
+                Render2D.FillRectangle(alphaRect, _value);
+            }
+
+            Render2D.FillRectangle(colorRect, _value with { A = 1 });
+            Render2D.DrawRectangle(fullRect, IsMouseOver || IsNavFocused ? style.BackgroundSelected : Color.Black);
         }
 
         /// <inheritdoc />

Source/Editor/GUI/Input/SliderControl.cs

@@ -368,6 +368,8 @@ namespace FlaxEditor.GUI.Input
         public SliderControl(float value, float x = 0, float y = 0, float width = 120, float min = float.MinValue, float max = float.MaxValue)
         : base(x, y, width, TextBox.DefaultHeight)
         {
+            AutoFocus = true;
+
             _min = min;
             _max = max;
             _value = Mathf.Clamp(value, min, max);

Source/Editor/GUI/Input/ValueBox.cs

@@ -266,6 +266,7 @@ namespace FlaxEditor.GUI.Input
             return base.OnMouseDown(location, button);
         }
 
+#if !PLATFORM_SDL
         /// <inheritdoc />
         public override void OnMouseMove(Float2 location)
         {
@@ -292,13 +293,45 @@ namespace FlaxEditor.GUI.Input
             base.OnMouseMove(location);
         }
 
+#else
+
+        /// <inheritdoc />
+        public override void OnMouseMoveRelative(Float2 mouseMotion)
+        {
+            var location = Root.TrackingMouseOffset;
+            if (_isSliding)
+            {
+                // Update sliding
+                ApplySliding(Root.TrackingMouseOffset.X * _slideSpeed);
+                return;
+            }
+
+            // Update cursor type so user knows they can slide value
+            if (CanUseSliding && SlideRect.Contains(location) && !_isSliding)
+            {
+                Cursor = CursorType.SizeWE;
+                _cursorChanged = true;
+            }
+            else if (_cursorChanged && !_isSliding)
+            {
+                Cursor = CursorType.Default;
+                _cursorChanged = false;
+            }
+
+            base.OnMouseMoveRelative(mouseMotion);
+        }
+
+#endif
+
         /// <inheritdoc />
         public override bool OnMouseUp(Float2 location, MouseButton button)
         {
             if (button == MouseButton.Left && _isSliding)
             {
+#if !PLATFORM_SDL
                 // End sliding and return mouse to original location
                 RootWindow.MousePosition = _mouseClickedPosition;
+#endif
                 EndSliding();
                 return true;
             }

Source/Editor/GUI/MainMenu.cs

@@ -12,16 +12,6 @@ namespace FlaxEditor.GUI
     /// <seealso cref="FlaxEngine.GUI.ContainerControl" />
     public sealed class MainMenu : ContainerControl
     {
-#if PLATFORM_WINDOWS
-        private bool _useCustomWindowSystem;
-        private Image _icon;
-        private Label _title;
-        private Button _closeButton;
-        private Button _minimizeButton;
-        private Button _maximizeButton;
-        private LocalizedString _charChromeRestore, _charChromeMaximize;
-        private Window _window;
-#endif
         private MainMenuButton _selected;
 
         /// <summary>
@@ -60,200 +50,12 @@ namespace FlaxEditor.GUI
         /// <summary>
         /// Initializes a new instance of the <see cref="MainMenu"/> class.
         /// </summary>
-        /// <param name="mainWindow">The main window.</param>
-        public MainMenu(RootControl mainWindow)
+        public MainMenu()
         : base(0, 0, 0, 20)
         {
             AutoFocus = false;
             AnchorPreset = AnchorPresets.HorizontalStretchTop;
-
-#if PLATFORM_WINDOWS
-            _useCustomWindowSystem = !Editor.Instance.Options.Options.Interface.UseNativeWindowSystem;
-            if (_useCustomWindowSystem)
-            {
-                BackgroundColor = Style.Current.LightBackground;
-                Height = 28;
-
-                var windowIcon = FlaxEngine.Content.LoadAsyncInternal<Texture>(EditorAssets.WindowIcon);
-                FontAsset windowIconsFont = FlaxEngine.Content.LoadAsyncInternal<FontAsset>(EditorAssets.WindowIconsFont);
-                Font iconFont = windowIconsFont?.CreateFont(9);
-
-                _window = mainWindow.RootWindow.Window;
-                _window.HitTest += OnHitTest;
-                _window.Closed += OnWindowClosed;
-
-                ScriptsBuilder.GetBinariesConfiguration(out _, out _, out _, out var configuration);
-
-                _icon = new Image
-                {
-                    Margin = new Margin(6, 6, 6, 6),
-                    Brush = new TextureBrush(windowIcon),
-                    Color = Style.Current.Foreground,
-                    KeepAspectRatio = false,
-                    TooltipText = string.Format("{0}\nVersion {1}\nConfiguration {3}\nGraphics {2}", _window.Title, Globals.EngineVersion, GPUDevice.Instance.RendererType, configuration),
-                    Parent = this,
-                };
-
-                _title = new Label(0, 0, Width, Height)
-                {
-                    Text = _window.Title,
-                    HorizontalAlignment = TextAlignment.Center,
-                    VerticalAlignment = TextAlignment.Center,
-                    ClipText = true,
-                    TextColor = Style.Current.ForegroundGrey,
-                    TextColorHighlighted = Style.Current.ForegroundGrey,
-                    Parent = this,
-                };
-
-                _closeButton = new Button
-                {
-                    Text = ((char)EditorAssets.SegMDL2Icons.ChromeClose).ToString(),
-                    Font = new FontReference(iconFont),
-                    BackgroundColor = Color.Transparent,
-                    BorderColor = Color.Transparent,
-                    BorderColorHighlighted = Color.Transparent,
-                    BorderColorSelected = Color.Transparent,
-                    TextColor = Style.Current.Foreground,
-                    Width = 46,
-                    BackgroundColorHighlighted = Color.Red,
-                    BackgroundColorSelected = Color.Red.RGBMultiplied(1.3f),
-                    Parent = this,
-                };
-                _closeButton.Clicked += () => _window.Close(ClosingReason.User);
-
-                _minimizeButton = new Button
-                {
-                    Text = ((char)EditorAssets.SegMDL2Icons.ChromeMinimize).ToString(),
-                    Font = new FontReference(iconFont),
-                    BackgroundColor = Color.Transparent,
-                    BorderColor = Color.Transparent,
-                    BorderColorHighlighted = Color.Transparent,
-                    BorderColorSelected = Color.Transparent,
-                    TextColor = Style.Current.Foreground,
-                    Width = 46,
-                    BackgroundColorHighlighted = Style.Current.LightBackground.RGBMultiplied(1.3f),
-                    Parent = this,
-                };
-                _minimizeButton.Clicked += () => _window.Minimize();
-
-                _maximizeButton = new Button
-                {
-                    Text = ((char)(_window.IsMaximized ? EditorAssets.SegMDL2Icons.ChromeRestore : EditorAssets.SegMDL2Icons.ChromeMaximize)).ToString(),
-                    Font = new FontReference(iconFont),
-                    BackgroundColor = Color.Transparent,
-                    BorderColor = Color.Transparent,
-                    BorderColorHighlighted = Color.Transparent,
-                    BorderColorSelected = Color.Transparent,
-                    TextColor = Style.Current.Foreground,
-                    Width = 46,
-                    BackgroundColorHighlighted = Style.Current.LightBackground.RGBMultiplied(1.3f),
-                    Parent = this,
-                };
-                _maximizeButton.Clicked += () =>
-                {
-                    if (_window.IsMaximized)
-                        _window.Restore();
-                    else
-                        _window.Maximize();
-                };
-                _charChromeRestore = ((char)EditorAssets.SegMDL2Icons.ChromeRestore).ToString();
-                _charChromeMaximize = ((char)EditorAssets.SegMDL2Icons.ChromeMaximize).ToString();
-            }
-            else
-#endif
-            {
-                BackgroundColor = Style.Current.LightBackground;
-            }
-        }
-
-#if PLATFORM_WINDOWS
-        /// <inheritdoc />
-        public override void Update(float deltaTime)
-        {
-            base.Update(deltaTime);
-
-            if (_maximizeButton != null)
-            {
-                _maximizeButton.Text = _window.IsMaximized ? _charChromeRestore : _charChromeMaximize;
-            }
-        }
-
-        private void OnWindowClosed()
-        {
-            if (_window != null)
-            {
-                _window.HitTest = null;
-                _window = null;
-            }
-        }
-
-        private WindowHitCodes OnHitTest(ref Float2 mouse)
-        {
-            var dpiScale = _window.DpiScale;
-
-            if (_window.IsMinimized)
-                return WindowHitCodes.NoWhere;
-
-            if (!_window.IsMaximized)
-            {
-                var pos = _window.ScreenToClient(mouse * dpiScale); // pos is not DPI adjusted
-                var winSize = _window.Size;
-
-                // Distance from which the mouse is considered to be on the border/corner
-                float distance = 5.0f * dpiScale;
-
-                if (pos.Y > winSize.Y - distance && pos.X < distance)
-                    return WindowHitCodes.BottomLeft;
-
-                if (pos.X > winSize.X - distance && pos.Y > winSize.Y - distance)
-                    return WindowHitCodes.BottomRight;
-
-                if (pos.Y < distance && pos.X < distance)
-                    return WindowHitCodes.TopLeft;
-
-                if (pos.Y < distance && pos.X > winSize.X - distance)
-                    return WindowHitCodes.TopRight;
-
-                if (pos.X > winSize.X - distance)
-                    return WindowHitCodes.Right;
-
-                if (pos.X < distance)
-                    return WindowHitCodes.Left;
-
-                if (pos.Y < distance)
-                    return WindowHitCodes.Top;
-
-                if (pos.Y > winSize.Y - distance)
-                    return WindowHitCodes.Bottom;
-            }
-
-            var mousePos = PointFromScreen(mouse * dpiScale);
-            var controlUnderMouse = GetChildAt(mousePos);
-            var isMouseOverSth = controlUnderMouse != null && controlUnderMouse != _title;
-            var rb = GetRightButton();
-            if (rb != null && _minimizeButton != null && new Rectangle(rb.UpperRight, _minimizeButton.BottomLeft - rb.UpperRight).Contains(ref mousePos) && !isMouseOverSth)
-                return WindowHitCodes.Caption;
-
-            return WindowHitCodes.Client;
-        }
-#endif
-
-        /// <summary>
-        /// Return the rightmost button.
-        /// </summary>
-        /// <returns>Rightmost button, null if there is no <see cref="MainMenuButton"/></returns>
-        private MainMenuButton GetRightButton()
-        {
-            MainMenuButton b = null;
-            foreach (var control in Children)
-            {
-                if (b == null && control is MainMenuButton)
-                    b = (MainMenuButton)control;
-
-                if (control is MainMenuButton && control.Right > b.Right)
-                    b = (MainMenuButton)control;
-            }
-            return b;
+            BackgroundColor = Style.Current.LightBackground;
         }
 
         /// <summary>
@@ -298,26 +100,6 @@ namespace FlaxEditor.GUI
             return result;
         }
 
-        /// <inheritdoc />
-        public override bool OnMouseDoubleClick(Float2 location, MouseButton button)
-        {
-            if (base.OnMouseDoubleClick(location, button))
-                return true;
-
-#if PLATFORM_WINDOWS
-            var child = GetChildAtRecursive(location);
-            if (_useCustomWindowSystem && child is not Button && child is not MainMenuButton)
-            {
-                if (_window.IsMaximized)
-                    _window.Restore();
-                else
-                    _window.Maximize();
-            }
-#endif
-
-            return true;
-        }
-
         /// <inheritdoc />
         public override bool OnKeyDown(KeyboardKeys key)
         {
@@ -333,16 +115,8 @@ namespace FlaxEditor.GUI
         protected override void PerformLayoutAfterChildren()
         {
             float x = 0;
-
-#if PLATFORM_WINDOWS
-            if (_useCustomWindowSystem)
-            {
-                // Icon
-                _icon.X = x;
-                _icon.Size = new Float2(Height);
-                x += _icon.Width;
-            }
-#endif
+            WindowDecorations decorations = Parent.GetChild<WindowDecorations>();
+            x += decorations?.Icon?.Width ?? 0;
 
             // Arrange controls
             MainMenuButton rightMostButton = null;
@@ -361,37 +135,21 @@ namespace FlaxEditor.GUI
                     x += b.Width;
                 }
             }
-
-#if PLATFORM_WINDOWS
-            if (_useCustomWindowSystem)
-            {
-                // Buttons
-                _closeButton.Height = Height;
-                _closeButton.X = Width - _closeButton.Width;
-                _maximizeButton.Height = Height;
-                _maximizeButton.X = _closeButton.X - _maximizeButton.Width;
-                _minimizeButton.Height = Height;
-                _minimizeButton.X = _maximizeButton.X - _minimizeButton.Width;
-
-                // Title
-                _title.Bounds = new Rectangle(x + 2, 0, _minimizeButton.Left - x - 4, Height);
-                //_title.Text = _title.Width < 300.0f ? Editor.Instance.ProjectInfo.Name : _window.Title;
-            }
-#endif
+            
+            // Fill the right side if title and buttons are not present
+            if (decorations?.Title == null)
+                Width = Parent.Width;
+            else
+                Width = x;
         }
 
-#if PLATFORM_WINDOWS
         /// <inheritdoc />
         public override void OnDestroy()
         {
             base.OnDestroy();
-
-            if (_window != null)
-            {
-                _window.Closed -= OnWindowClosed;
-                OnWindowClosed();
-            }
+            
+            if (_selected != null)
+                Selected = null;
         }
-#endif
     }
 }

Source/Editor/GUI/MainMenuButton.cs

@@ -42,14 +42,12 @@ namespace FlaxEditor.GUI
             Text = text;
 
             var style = Style.Current;
-#if PLATFORM_WINDOWS
-            if (Editor.Instance.Options.Options.Interface.UseNativeWindowSystem)
+            if (!Utilities.Utils.UseCustomWindowDecorations())
             {
                 BackgroundColorMouseOver = style.BackgroundHighlighted;
                 BackgroundColorMouseOverOpened = style.Background;
             }
             else
-#endif
             {
                 BackgroundColorMouseOver = BackgroundColorMouseOverOpened = style.LightBackground * 1.3f;
             }

Source/Editor/GUI/Tree/TreeNode.cs

@@ -319,6 +319,8 @@ namespace FlaxEditor.GUI.Tree
         public TreeNode(bool canChangeOrder, SpriteHandle iconCollapsed, SpriteHandle iconOpened)
         : base(0, 0, 64, 16)
         {
+            AutoFocus = true;
+
             _canChangeOrder = canChangeOrder;
             _animationProgress = 1.0f;
             _cachedHeight = _headerHeight;

Source/Editor/GUI/WindowDecorations.cs

@@ -0,0 +1,342 @@
+// Copyright (c) Wojciech Figat. All rights reserved.
+
+using System;
+using FlaxEditor.GUI.Docking;
+using FlaxEditor.Options;
+using FlaxEngine;
+using FlaxEngine.GUI;
+
+namespace FlaxEditor.GUI;
+
+/// <summary>
+/// Represents the title bar of the window with buttons.
+/// </summary>
+/// <seealso cref="FlaxEngine.GUI.ContainerControl" />
+public class WindowDecorations : ContainerControl
+{
+    private Image _icon;
+    private Label _title;
+    private Button _closeButton;
+    private Button _minimizeButton;
+    private Button _maximizeButton;
+    private LocalizedString _charChromeRestore, _charChromeMaximize;
+    private Window _window;
+
+    /// <summary>
+    /// The title label in the title bar.
+    /// </summary>
+    public Label Title => _title;
+    
+    /// <summary>
+    /// The icon used in the title bar.
+    /// </summary>
+    public Image Icon => _icon;
+    
+    /// <summary>
+    /// The tooltip shown when hovering over the icon.
+    /// </summary>
+    public string IconTooltipText
+    {
+        get => _icon?.TooltipText ?? null;
+        set
+        {
+            if (_icon != null)
+                _icon.TooltipText = value;
+        }
+    }
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="WindowDecorations"/> class.
+    /// </summary>
+    /// <param name="window">The window.</param>
+    /// <param name="iconOnly">When set, omit drawing title and buttons.</param>
+    public WindowDecorations(RootControl window, bool iconOnly = false)
+    : base(0, 0, 0, 20)
+    {
+        _window = window.RootWindow.Window;
+        
+        AutoFocus = false;
+        AnchorPreset = AnchorPresets.HorizontalStretchTop;
+        BackgroundColor = Color.Transparent;
+
+        var windowIcon = FlaxEngine.Content.LoadAsyncInternal<Texture>(EditorAssets.WindowIcon);
+
+        _icon = new Image
+        {
+            Margin = new Margin(4, 4, 4, 4),
+            Brush = new TextureBrush(windowIcon),
+            Color = Style.Current.Foreground,
+            BackgroundColor = Style.Current.LightBackground,
+            KeepAspectRatio = false,
+            Parent = this,
+        };
+
+        if (!iconOnly)
+        {
+            _icon.Margin = new Margin(6, 6, 6, 6);
+            Height = 28;
+            
+            _window.HitTest += OnHitTest;
+            _window.Closed += OnWindowClosed;
+            
+            FontAsset windowIconsFont = FlaxEngine.Content.LoadAsyncInternal<FontAsset>(EditorAssets.WindowIconsFont);
+            Font iconFont = windowIconsFont?.CreateFont(9);
+            
+            _title = new Label(0, 0, Width, Height)
+            {
+                Text = _window.Title,
+                HorizontalAlignment = TextAlignment.Center,
+                VerticalAlignment = TextAlignment.Center,
+                ClipText = true,
+                TextColor = Style.Current.ForegroundGrey,
+                TextColorHighlighted = Style.Current.ForegroundGrey,
+                BackgroundColor = Style.Current.LightBackground,
+                Parent = this,
+            };
+
+            _closeButton = new Button
+            {
+                Text = ((char)EditorAssets.SegMDL2Icons.ChromeClose).ToString(),
+                Font = new FontReference(iconFont),
+                BackgroundColor = Style.Current.LightBackground,
+                BorderColor = Color.Transparent,
+                BorderColorHighlighted = Color.Transparent,
+                BorderColorSelected = Color.Transparent,
+                TextColor = Style.Current.Foreground,
+                Width = 46,
+                BackgroundColorHighlighted = Color.Red,
+                BackgroundColorSelected = Color.Red.RGBMultiplied(1.3f),
+                Parent = this,
+            };
+            _closeButton.Clicked += () => _window.Close(ClosingReason.User);
+
+            _minimizeButton = new Button
+            {
+                Text = ((char)EditorAssets.SegMDL2Icons.ChromeMinimize).ToString(),
+                Font = new FontReference(iconFont),
+                BackgroundColor = Style.Current.LightBackground,
+                BorderColor = Color.Transparent,
+                BorderColorHighlighted = Color.Transparent,
+                BorderColorSelected = Color.Transparent,
+                TextColor = Style.Current.Foreground,
+                Width = 46,
+                BackgroundColorHighlighted = Style.Current.LightBackground.RGBMultiplied(1.3f),
+                Parent = this,
+            };
+            _minimizeButton.Clicked += () => _window.Minimize();
+
+            _maximizeButton = new Button
+            {
+                Text = ((char)(_window.IsMaximized ? EditorAssets.SegMDL2Icons.ChromeRestore : EditorAssets.SegMDL2Icons.ChromeMaximize)).ToString(),
+                Font = new FontReference(iconFont),
+                BackgroundColor = Style.Current.LightBackground,
+                BorderColor = Color.Transparent,
+                BorderColorHighlighted = Color.Transparent,
+                BorderColorSelected = Color.Transparent,
+                TextColor = Style.Current.Foreground,
+                Width = 46,
+                BackgroundColorHighlighted = Style.Current.LightBackground.RGBMultiplied(1.3f),
+                Parent = this,
+            };
+            _maximizeButton.Clicked += () =>
+            {
+                if (_window.IsMaximized)
+                    _window.Restore();
+                else
+                    _window.Maximize();
+            };
+
+            _charChromeRestore = ((char)EditorAssets.SegMDL2Icons.ChromeRestore).ToString();
+            _charChromeMaximize = ((char)EditorAssets.SegMDL2Icons.ChromeMaximize).ToString();
+        }
+    }
+    
+    /// <inheritdoc />
+    public override void Update(float deltaTime)
+    {
+        base.Update(deltaTime);
+
+        if (_maximizeButton != null)
+        {
+            var maximizeText = _window.IsMaximized ? _charChromeRestore : _charChromeMaximize;
+            if (_maximizeButton.Text != maximizeText)
+                _maximizeButton.Text = maximizeText;
+        }
+    }
+
+    private void OnWindowClosed()
+    {
+        if (_window != null)
+        {
+            _window.HitTest -= OnHitTest;
+            _window = null;
+        }
+    }
+
+    /// <summary>
+    /// Perform hit test on the window.
+    /// </summary>
+    /// <param name="mouse">The mouse position</param>
+    /// <returns>The hit code for given position.</returns>
+    protected virtual WindowHitCodes OnHitTest(ref Float2 mouse)
+    {
+        if (_window.IsMinimized)
+            return WindowHitCodes.NoWhere;
+
+        var dpiScale = _window.DpiScale;
+        var pos = _window.ScreenToClient(mouse * dpiScale); // pos is not DPI adjusted
+        if (!_window.IsMaximized)
+        {
+            var winSize = _window.Size;
+
+            // Distance from which the mouse is considered to be on the border/corner
+            float distance = 5.0f * dpiScale;
+
+            if (pos.Y > winSize.Y - distance && pos.X < distance)
+                return WindowHitCodes.BottomLeft;
+
+            if (pos.X > winSize.X - distance && pos.Y > winSize.Y - distance)
+                return WindowHitCodes.BottomRight;
+
+            if (pos.Y < distance && pos.X < distance)
+                return WindowHitCodes.TopLeft;
+
+            if (pos.Y < distance && pos.X > winSize.X - distance)
+                return WindowHitCodes.TopRight;
+
+            if (pos.X > winSize.X - distance)
+                return WindowHitCodes.Right;
+
+            if (pos.X < distance)
+                return WindowHitCodes.Left;
+
+            if (pos.Y < distance)
+                return WindowHitCodes.Top;
+
+            if (pos.Y > winSize.Y - distance)
+                return WindowHitCodes.Bottom;
+        }
+        
+        var controlUnderMouse = GetChildAt(pos, control => control != _title);
+        if (_title.Bounds.Contains(pos) && controlUnderMouse == null)
+            return WindowHitCodes.Caption;
+
+        return WindowHitCodes.Client;
+    }
+    
+    /// <inheritdoc />
+    public override bool OnMouseDoubleClick(Float2 location, MouseButton button)
+    {
+        // These may not work with main window due to SDL not passing mouse events
+        // when interacting with hit tests on caption area...
+        
+        if (Title.Bounds.Contains(location) && button == MouseButton.Left)
+        {
+            if (_window.IsMaximized)
+                _window.Restore();
+            else
+                _window.Maximize();
+            return true;
+        }
+        else if (Icon.Bounds.Contains(location) && button == MouseButton.Left)
+        {
+            _window.Close(ClosingReason.User);
+            return true;
+        }
+        return base.OnMouseDoubleClick(location, button);
+    }
+
+    /// <inheritdoc />
+    protected override void PerformLayoutAfterChildren()
+    {
+        // Calculate extents for title bounds area excluding the icon and main menu area
+        float x = 0;
+        
+        // Icon
+        if (_icon != null)
+        {
+            _icon.X = x;
+            _icon.Size = new Float2(Height);
+            x += _icon.Width;
+        }
+
+        // Main menu if present
+        if (Parent.GetChild<MainMenu>() is MainMenu mainMenu)
+        {
+            for (int i = 0; i < mainMenu.Children.Count; i++)
+            {
+                var c = mainMenu.Children[i];
+                if (c is MainMenuButton b && c.Visible)
+                {
+                    b.Bounds = new Rectangle(x, 0, b.Width, Height);
+                    x += b.Width;
+                }
+            }
+        }
+     
+        // Buttons
+        float rightMostButtonX = Width;
+        if (_closeButton != null)
+        {
+            _closeButton.Height = Height;
+            _closeButton.X = rightMostButtonX - _closeButton.Width;
+            rightMostButtonX = _closeButton.X;
+        }
+        if (_maximizeButton != null)
+        {
+            _maximizeButton.Height = Height;
+            _maximizeButton.X = rightMostButtonX - _maximizeButton.Width;
+            rightMostButtonX = _maximizeButton.X;
+        }
+        if (_minimizeButton != null)
+        {
+            _minimizeButton.Height = Height;
+            _minimizeButton.X = rightMostButtonX - _minimizeButton.Width;
+            rightMostButtonX = _minimizeButton.X;
+        }
+
+        // Title
+        if (_title != null)
+        {
+            _title.Text = _window.Title;
+            _title.Bounds = new Rectangle(x, 0, rightMostButtonX - x, Height);
+        }
+    }
+    
+    /// <inheritdoc />
+    public override void Draw()
+    {
+        base.Draw();
+        DrawBorders();
+    }
+
+    /// <summary>
+    /// Draw borders around the window.
+    /// </summary>
+    public virtual void DrawBorders()
+    {
+        var win = RootWindow.Window;
+        if (win.IsMaximized)
+            return;
+
+        if (Editor.Instance.UI.StatusBar == null)
+            return;
+        
+        const float thickness = 1.0f;
+        Color color = Editor.Instance.UI.StatusBar.StatusColor;
+        Rectangle rect = new Rectangle(thickness * 0.5f, thickness * 0.5f, Parent.Width - thickness, Parent.Height - thickness);
+        Render2D.DrawRectangle(rect, color);
+    }
+
+    /// <inheritdoc />
+    public override void OnDestroy()
+    {
+        base.OnDestroy();
+
+        if (_window != null)
+        {
+            _window.Closed -= OnWindowClosed;
+            OnWindowClosed();
+        }
+    }
+}

Source/Editor/Gizmo/TransformGizmo.cs

@@ -155,6 +155,7 @@ namespace FlaxEditor.Gizmo
             // Ensure player is not moving objects
             if (ActiveAxis != Axis.None)
                 return;
+            Profiler.BeginEvent("Pick");
 
             // Get mouse ray and try to hit any object
             var ray = Owner.MouseRay;
@@ -243,6 +244,8 @@ namespace FlaxEditor.Gizmo
             {
                 sceneEditing.Deselect();
             }
+
+            Profiler.EndEvent();
         }
 
         /// <inheritdoc />

Source/Editor/Managed/ManagedEditor.Internal.cpp

@@ -402,10 +402,11 @@ DEFINE_INTERNAL_CALL(void) EditorInternal_RunVisualScriptBreakpointLoopTick(floa
                 break;
             }
         }
+        WindowsManager::WindowsLocker.Unlock();
         for (const auto& e : inputEvents)
         {
             auto window = e.Target ? e.Target : defaultWindow;
-            if (!window)
+            if (!window || window->IsClosed())
                 continue;
             switch (e.Type)
             {
@@ -435,12 +436,14 @@ DEFINE_INTERNAL_CALL(void) EditorInternal_RunVisualScriptBreakpointLoopTick(floa
             case InputDevice::EventType::MouseMove:
                 window->OnMouseMove(window->ScreenToClient(e.MouseData.Position));
                 break;
+            case InputDevice::EventType::MouseMoveRelative:
+                window->OnMouseMoveRelative(e.MouseMovementData.PositionRelative);
+                break;
             case InputDevice::EventType::MouseLeave:
                 window->OnMouseLeave();
                 break;
             }
         }
-        WindowsManager::WindowsLocker.Unlock();
     }
     WindowsManager::WindowsLocker.Lock();
     Array<Window*, InlinedAllocation<32>> windows;

Source/Editor/Managed/ManagedEditor.cpp

@@ -14,6 +14,7 @@
 #include "Engine/Platform/WindowsManager.h"
 #include "Engine/Content/Assets/VisualScript.h"
 #include "Engine/Content/Content.h"
+#include "Engine/Level/Actor.h"
 #include "Engine/CSG/CSGBuilder.h"
 #include "Engine/Engine/CommandLine.h"
 #include "Engine/Renderer/ProbesRenderer.h"
@@ -75,7 +76,7 @@ void OnLightmapsBuildFinished(bool failed)
         OnLightmapsBake(ShadowsOfMordor::BuildProgressStep::GenerateLightmapCharts, 0, 0, false);
 }
 
-void OnBakeEvent(bool started, const ProbesRenderer::Entry& e)
+void OnBakeEvent(bool started, Actor* e)
 {
     if (Internal_EnvProbeBake == nullptr)
     {
@@ -83,7 +84,7 @@ void OnBakeEvent(bool started, const ProbesRenderer::Entry& e)
         ASSERT(Internal_EnvProbeBake);
     }
 
-    MObject* probeObj = e.Actor ? e.Actor->GetManagedInstance() : nullptr;
+    MObject* probeObj = e ? e->GetManagedInstance() : nullptr;
 
     MainThreadManagedInvokeAction::ParamsBuilder params;
     params.AddParam(started);
@@ -91,12 +92,12 @@ void OnBakeEvent(bool started, const ProbesRenderer::Entry& e)
     MainThreadManagedInvokeAction::Invoke(Internal_EnvProbeBake, params);
 }
 
-void OnRegisterBake(const ProbesRenderer::Entry& e)
+void OnRegisterBake(Actor* e)
 {
     OnBakeEvent(true, e);
 }
 
-void OnFinishBake(const ProbesRenderer::Entry& e)
+void OnFinishBake(Actor* e)
 {
     OnBakeEvent(false, e);
 }
@@ -157,7 +158,9 @@ ManagedEditor::ManagedEditor()
     lightmapsBuilder->OnBuildProgress.Bind<OnLightmapsBuildProgress>();
     lightmapsBuilder->OnBuildFinished.Bind<OnLightmapsBuildFinished>();
     CSG::Builder::OnBrushModified.Bind<OnBrushModified>();
+#if LOG_ENABLE
     Log::Logger::OnMessage.Bind<OnLogMessage>();
+#endif
     VisualScripting::DebugFlow.Bind<OnVisualScriptingDebugFlow>();
 }
 
@@ -173,7 +176,9 @@ ManagedEditor::~ManagedEditor()
     lightmapsBuilder->OnBuildProgress.Unbind<OnLightmapsBuildProgress>();
     lightmapsBuilder->OnBuildFinished.Unbind<OnLightmapsBuildFinished>();
     CSG::Builder::OnBrushModified.Unbind<OnBrushModified>();
+#if LOG_ENABLE
     Log::Logger::OnMessage.Unbind<OnLogMessage>();
+#endif
     VisualScripting::DebugFlow.Unbind<OnVisualScriptingDebugFlow>();
 }
 

Source/Editor/Modules/ContentDatabaseModule.cs

@@ -1013,7 +1013,7 @@ namespace FlaxEditor.Modules
                     ContentItem item;
                     if (path.EndsWith(".cs"))
                         item = new CSharpScriptItem(path);
-                    else if (path.EndsWith(".cpp") || path.EndsWith(".h"))
+                    else if (path.EndsWith(".cpp") || path.EndsWith(".h") || path.EndsWith(".c") || path.EndsWith(".hpp"))
                         item = new CppScriptItem(path);
                     else if (path.EndsWith(".shader") || path.EndsWith(".hlsl"))
                         item = new ShaderSourceItem(path);

Source/Editor/Modules/ContentImportingModule.cs

@@ -222,7 +222,7 @@ namespace FlaxEditor.Modules
                 outputExtension = extension;
 
                 // Check if can place source files here
-                if (!targetLocation.CanHaveScripts && (extension == ".cs" || extension == ".cpp" || extension == ".h"))
+                if (!targetLocation.CanHaveScripts && (extension == ".cs" || extension == ".cpp" || extension == ".h" || extension == ".c" || extension == ".hpp"))
                 {
                     // Error
                     Editor.LogWarning(string.Format("Cannot import \'{0}\' to \'{1}\'. The target directory cannot have scripts.", inputPath, targetLocation.Node.Path));

Source/Editor/Modules/SceneEditingModule.cs

@@ -712,7 +712,11 @@ namespace FlaxEditor.Modules
 
         private void OnActorChildNodesDispose(ActorNode node)
         {
+            if (Selection.Count == 0)
+                return;
+
             // TODO: cache if selection contains any actor child node and skip this loop if no need to iterate
+            // TODO: or build a hash set with selected nodes for quick O(1) checks (cached until selection changes)
 
             // Deselect child nodes
             for (int i = 0; i < node.ChildNodes.Count; i++)

Source/Editor/Modules/SceneModule.cs

@@ -3,6 +3,7 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Linq;
 using FlaxEditor.SceneGraph;
 using FlaxEditor.SceneGraph.Actors;
 using FlaxEngine;
@@ -662,6 +663,48 @@ namespace FlaxEditor.Modules
             //node?.TreeNode.OnActiveChanged();
         }
 
+        private void OnActorDestroyChildren(Actor actor)
+        {
+            // Instead of doing OnActorParentChanged for every child lets remove all of them at once from that actor
+            ActorNode node = GetActorNode(actor);
+            if (node != null)
+            {
+                if (Editor.SceneEditing.HasSthSelected)
+                {
+                    // Clear selection if one of the removed actors is selected
+                    var selection = new HashSet<Actor>();
+                    foreach (var e in Editor.SceneEditing.Selection)
+                    {
+                        if (e is ActorNode q && q.Actor)
+                            selection.Add(q.Actor);
+                    }
+                    var count = actor.ChildrenCount;
+                    for (int i = 0; i < count; i++)
+                    {
+                        var child = actor.GetChild(i);
+                        if (selection.Contains(child))
+                        {
+                            Editor.SceneEditing.Deselect();
+                            break;
+                        }
+                    }
+                }
+
+                // Remove all child nodes (upfront remove all nodes to run faster)
+                for (int i = 0; i < node.ChildNodes.Count; i++)
+                {
+                    if (node.ChildNodes[i] is ActorNode child)
+                        child.parentNode = null;
+                }
+                node.TreeNode.DisposeChildren();
+                for (int i = 0; i < node.ChildNodes.Count; i++)
+                {
+                    node.ChildNodes[i].Dispose();
+                }
+                node.ChildNodes.Clear();
+            }
+        }
+
         /// <summary>
         /// Gets the actor node.
         /// </summary>
@@ -713,6 +756,7 @@ namespace FlaxEditor.Modules
             Level.ActorOrderInParentChanged += OnActorOrderInParentChanged;
             Level.ActorNameChanged += OnActorNameChanged;
             Level.ActorActiveChanged += OnActorActiveChanged;
+            Level.ActorDestroyChildren += OnActorDestroyChildren;
         }
 
         /// <inheritdoc />
@@ -730,6 +774,7 @@ namespace FlaxEditor.Modules
             Level.ActorOrderInParentChanged -= OnActorOrderInParentChanged;
             Level.ActorNameChanged -= OnActorNameChanged;
             Level.ActorActiveChanged -= OnActorActiveChanged;
+            Level.ActorDestroyChildren -= OnActorDestroyChildren;
 
             // Cleanup graph
             Root.Dispose();

Source/Editor/Modules/SimulationModule.cs

@@ -267,7 +267,7 @@ namespace FlaxEditor.Modules
         }
 
         /// <inheritdoc />
-        public override void OnPlayBegin()
+        public override void OnPlayBeginning()
         {
             Editor.Windows.FlashMainWindow();
 

Source/Editor/Modules/UIModule.cs

@@ -16,7 +16,6 @@ using FlaxEditor.Windows;
 using FlaxEngine;
 using FlaxEngine.GUI;
 using FlaxEngine.Json;
-using DockHintWindow = FlaxEditor.GUI.Docking.DockHintWindow;
 using MasterDockPanel = FlaxEditor.GUI.Docking.MasterDockPanel;
 using FlaxEditor.Content.Settings;
 using FlaxEditor.Options;
@@ -29,6 +28,40 @@ namespace FlaxEditor.Modules
     /// <seealso cref="FlaxEditor.Modules.EditorModule" />
     public sealed class UIModule : EditorModule
     {
+        private class MainWindowDecorations : WindowDecorations
+        {
+            public MainWindowDecorations(RootControl window, bool iconOnly) 
+            : base(window, iconOnly)
+            {
+            }
+
+            /// <inheritdoc />
+            public override bool OnKeyDown(KeyboardKeys key)
+            {
+                if (base.OnKeyDown(key))
+                    return true;
+
+                // Fallback to the edit window for shortcuts
+                var editor = Editor.Instance;
+                return editor.Windows.EditWin.InputActions.Process(editor, this, key);
+            }
+            
+            /// <inheritdoc />
+            public override void DrawBorders()
+            {
+                // Draw main window borders if using a custom style
+                var win = RootWindow.Window;
+                if (win.IsMaximized)
+                    return;
+
+                var color = Editor.Instance.UI.StatusBar.StatusColor;
+                var rect = new Rectangle(0.5f, 0.5f, Parent.Width - 1.0f, Parent.Height - 1.0f - StatusBar.DefaultHeight);
+                Render2D.DrawLine(rect.UpperLeft, rect.UpperRight, color);
+                Render2D.DrawLine(rect.UpperLeft, rect.BottomLeft, color);
+                Render2D.DrawLine(rect.UpperRight, rect.BottomRight, color);
+            }
+        }
+        
         private Label _progressLabel;
         private ProgressBar _progressBar;
         private Button _outputLogButton;
@@ -144,6 +177,11 @@ namespace FlaxEditor.Modules
         /// </summary>
         public MainMenu MainMenu;
 
+        /// <summary>
+        /// The window decorations (title bar with buttons)
+        /// </summary>
+        public WindowDecorations WindowDecorations;
+
         /// <summary>
         /// The tool strip control.
         /// </summary>
@@ -426,19 +464,11 @@ namespace FlaxEditor.Modules
             InitToolstrip(mainWindow);
             InitStatusBar(mainWindow);
             InitDockPanel(mainWindow);
+            InitWindowDecorations(mainWindow);
 
             Editor.Options.OptionsChanged += OnOptionsChanged;
-
-            // Add dummy control for drawing the main window borders if using a custom style
-#if PLATFORM_WINDOWS
-            if (!Editor.Options.Options.Interface.UseNativeWindowSystem)
-#endif
-            {
-                mainWindow.AddChild(new CustomWindowBorderControl
-                {
-                    Size = Float2.Zero,
-                });
-            }
+            
+            mainWindow.PerformLayout(true);
         }
 
         private void InitViewportScaleOptions()
@@ -510,23 +540,6 @@ namespace FlaxEditor.Modules
             }
         }
 
-        private class CustomWindowBorderControl : Control
-        {
-            /// <inheritdoc />
-            public override void Draw()
-            {
-                var win = RootWindow.Window;
-                if (win.IsMaximized)
-                    return;
-
-                var color = Editor.Instance.UI.StatusBar.StatusColor;
-                var rect = new Rectangle(0.5f, 0.5f, Parent.Width - 1.0f, Parent.Height - 1.0f - StatusBar.DefaultHeight);
-                Render2D.DrawLine(rect.UpperLeft, rect.UpperRight, color);
-                Render2D.DrawLine(rect.UpperLeft, rect.BottomLeft, color);
-                Render2D.DrawLine(rect.UpperRight, rect.BottomRight, color);
-            }
-        }
-
         /// <inheritdoc />
         public override void OnEndInit()
         {
@@ -558,13 +571,6 @@ namespace FlaxEditor.Modules
             UpdateToolstrip();
         }
 
-        /// <inheritdoc />
-        public override void OnExit()
-        {
-            // Cleanup dock panel hint proxy windows (Flax will destroy them by var but it's better to clear them earlier)
-            DockHintWindow.Proxy.Dispose();
-        }
-
         private IColorPickerDialog ShowPickColorDialog(Control targetControl, Color initialValue, ColorValueBox.ColorPickerEvent colorChanged, ColorValueBox.ColorPickerClosedEvent pickerClosed, bool useDynamicEditing)
         {
             var dialog = new ColorPickerDialog(initialValue, colorChanged, pickerClosed, useDynamicEditing);
@@ -618,10 +624,12 @@ namespace FlaxEditor.Modules
 
         private void InitMainMenu(RootControl mainWindow)
         {
-            MainMenu = new MainMenu(mainWindow)
+            MainMenu = new MainMenu()
             {
                 Parent = mainWindow
             };
+            if (Utilities.Utils.UseCustomWindowDecorations(isMainWindow: true))
+                MainMenu.Height = 28;
 
             var inputOptions = Editor.Options.Options.Input;
 
@@ -762,6 +770,20 @@ namespace FlaxEditor.Modules
             cm.AddButton("Information about Flax", () => new AboutDialog().Show());
         }
 
+        private void InitWindowDecorations(RootControl mainWindow)
+        {
+            ScriptsBuilder.GetBinariesConfiguration(out _, out _, out _, out var configuration);
+            var driver = Platform.DisplayServer;
+            if (!string.IsNullOrEmpty(driver))
+                driver = $" ({driver})";
+            
+            WindowDecorations = new MainWindowDecorations(mainWindow, !Utilities.Utils.UseCustomWindowDecorations(isMainWindow: true))
+            {
+                Parent = mainWindow,
+                IconTooltipText = $"{mainWindow.RootWindow.Title}\nVersion {Globals.EngineVersion}\nConfiguration {configuration}\nGraphics {GPUDevice.Instance.RendererType}{driver}",
+            };
+        }
+        
         private void OnOptionsChanged(EditorOptions options)
         {
             var inputOptions = options.Input;
@@ -1182,6 +1204,7 @@ namespace FlaxEditor.Modules
         {
             // Clear UI references (GUI cannot be used after window closing)
             MainMenu = null;
+            WindowDecorations = null;
             ToolStrip = null;
             MasterPanel = null;
             StatusBar = null;

Source/Editor/Modules/WindowsModule.cs

@@ -10,7 +10,6 @@ using System.Text;
 using System.Xml;
 using FlaxEditor.Content;
 using FlaxEditor.GUI.Dialogs;
-using FlaxEditor.GUI.Docking;
 using FlaxEditor.Windows;
 using FlaxEditor.Windows.Assets;
 using FlaxEditor.Windows.Profiler;
@@ -758,17 +757,19 @@ namespace FlaxEditor.Modules
             var settings = CreateWindowSettings.Default;
             settings.Title = "Flax Editor";
             settings.Size = Platform.DesktopSize * 0.75f;
+            settings.MinimumSize = new Float2(200, 150);
             settings.StartPosition = WindowStartPosition.CenterScreen;
             settings.ShowAfterFirstPaint = true;
-#if PLATFORM_WINDOWS
-            if (!Editor.Instance.Options.Options.Interface.UseNativeWindowSystem)
+            
+            if (Utilities.Utils.UseCustomWindowDecorations(isMainWindow: true))
             {
                 settings.HasBorder = false;
-
+#if PLATFORM_WINDOWS && !PLATFORM_SDL
                 // Skip OS sizing frame and implement it using LeftButtonHit
                 settings.HasSizingFrame = false;
+#endif
             }
-#elif PLATFORM_LINUX
+#if PLATFORM_LINUX && !PLATFORM_SDL
             settings.HasBorder = false;
 #endif
             MainWindow = Platform.CreateWindow(ref settings);

Source/Editor/Options/InterfaceOptions.cs

@@ -179,6 +179,34 @@ namespace FlaxEditor.Options
             GameWindowThenRestore,
         }
 
+        /// <summary>
+        /// Options for type of window decorations to use.
+        /// </summary>
+        public enum WindowDecorationsType
+        {
+            /// <summary>
+            /// Determined automatically based on the system and any known compatibility issues with native decorations.
+            /// </summary>
+            Auto,
+            
+            /// <summary>
+            /// Automatically choose most compatible window decorations for child windows, prefer custom decorations on main window.
+            /// </summary>
+            [EditorDisplay(Name = "Auto (Child Only)")]
+            AutoChildOnly,
+            
+            /// <summary>
+            /// Use native system window decorations on all windows.
+            /// </summary>
+            Native,
+            
+            /// <summary>
+            /// Use custom client-side window decorations on all windows.
+            /// </summary>
+            [EditorDisplay(Name = "Client-side")]
+            ClientSide,
+        }
+
         /// <summary>
         /// Gets or sets the Editor User Interface scale. Applied to all UI elements, windows and text. Can be used to scale the interface up on a bigger display. Editor restart required.
         /// </summary>
@@ -268,7 +296,14 @@ namespace FlaxEditor.Options
         [EditorDisplay("Interface"), EditorOrder(322)]
         public bool ScrollToScriptOnAdd { get; set; } = true;
 
-#if PLATFORM_WINDOWS
+#if PLATFORM_SDL
+        /// <summary>
+        /// Gets or sets a value indicating whether use native window title bar decorations in child windows. Editor restart required.
+        /// </summary>
+        [DefaultValue(WindowDecorationsType.AutoChildOnly)]
+        [EditorDisplay("Interface"), EditorOrder(70), Tooltip("Determines whether use native window title bar decorations. Editor restart required.")]
+        public WindowDecorationsType WindowDecorations { get; set; } = WindowDecorationsType.AutoChildOnly;
+#elif PLATFORM_WINDOWS
         /// <summary>
         /// Gets or sets a value indicating whether use native window title bar. Editor restart required.
         /// </summary>
@@ -277,7 +312,7 @@ namespace FlaxEditor.Options
         public bool UseNativeWindowSystem { get; set; } = false;
 #endif
 
-#if PLATFORM_WINDOWS
+#if PLATFORM_SDL || PLATFORM_WINDOWS
         /// <summary>
         /// Gets or sets a value indicating whether a window containing a single tabs hides the tab bar. Editor restart recommended.
         /// </summary>

Source/Editor/ProjectInfo.cpp

@@ -6,6 +6,7 @@
 #include "Engine/Core/Log.h"
 #include "Engine/Engine/Globals.h"
 #include "Engine/Core/Math/Quaternion.h"
+#include "Engine/Profiler/ProfilerMemory.h"
 #include "Engine/Serialization/JsonWriters.h"
 #include "Engine/Serialization/JsonTools.h"
 #include <ThirdParty/pugixml/pugixml.hpp>
@@ -327,6 +328,7 @@ ProjectInfo* ProjectInfo::Load(const String& path)
     }
 
     // Load
+    PROFILE_MEM(Editor);
     auto project = New<ProjectInfo>();
     if (project->LoadProject(path))
     {

Source/Editor/SceneGraph/RootNode.cs

@@ -97,13 +97,16 @@ namespace FlaxEditor.SceneGraph
         /// <returns>Hit object or null if there is no intersection at all.</returns>
         public SceneGraphNode RayCast(ref Ray ray, ref Ray view, out Real distance, RayCastData.FlagTypes flags = RayCastData.FlagTypes.None)
         {
+            Profiler.BeginEvent("RayCastScene");
             var data = new RayCastData
             {
                 Ray = ray,
                 View = view,
                 Flags = flags
             };
-            return RayCast(ref data, out distance, out _);
+            var result = RayCast(ref data, out distance, out _);
+            Profiler.EndEvent();
+            return result;
         }
 
         /// <summary>
@@ -117,13 +120,16 @@ namespace FlaxEditor.SceneGraph
         /// <returns>Hit object or null if there is no intersection at all.</returns>
         public SceneGraphNode RayCast(ref Ray ray, ref Ray view, out Real distance, out Vector3 normal, RayCastData.FlagTypes flags = RayCastData.FlagTypes.None)
         {
+            Profiler.BeginEvent("RayCastScene");
             var data = new RayCastData
             {
                 Ray = ray,
                 View = view,
                 Flags = flags
             };
-            return RayCast(ref data, out distance, out normal);
+            var result = RayCast(ref data, out distance, out normal);
+            Profiler.EndEvent();
+            return result;
         }
 
         internal static Quaternion RaycastNormalRotation(ref Vector3 normal)

Source/Editor/SceneGraph/SceneGraphNode.cs

@@ -27,7 +27,7 @@ namespace FlaxEditor.SceneGraph
         /// <summary>
         /// The parent node.
         /// </summary>
-        protected SceneGraphNode parentNode;
+        internal SceneGraphNode parentNode;
 
         /// <summary>
         /// Gets the children list.

Source/Editor/Scripting/CodeEditor.cpp

@@ -13,6 +13,7 @@
 #include "Engine/Engine/EngineService.h"
 #include "Engine/Platform/Thread.h"
 #include "Engine/Threading/IRunnable.h"
+#include "Engine/Profiler/ProfilerMemory.h"
 
 void OnAsyncBegin(Thread* thread);
 void OnAsyncEnd();
@@ -232,6 +233,8 @@ void OnAsyncEnd()
 
 bool CodeEditingManagerService::Init()
 {
+    PROFILE_MEM(Editor);
+
     // Try get editors
 #if USE_VISUAL_STUDIO_DTE
     VisualStudioEditor::FindEditors(&CodeEditors);

Source/Editor/Scripting/ScriptsBuilder.cpp

@@ -23,6 +23,7 @@
 #include "Engine/Scripting/Scripting.h"
 #include "Engine/Scripting/Script.h"
 #include "Engine/Profiler/ProfilerCPU.h"
+#include "Engine/Profiler/ProfilerMemory.h"
 #include "Engine/Level/Level.h"
 #include "FlaxEngine.Gen.h"
 
@@ -77,7 +78,7 @@ namespace ScriptsBuilderImpl
     void onScriptsReloadEnd();
     void onScriptsLoaded();
 
-    void GetClassName(const StringAnsi& fullname, StringAnsi& className);
+    void GetClassName(const StringAnsiView fullname, StringAnsi& className);
 
     void onCodeEditorAsyncOpenBegin()
     {
@@ -120,9 +121,13 @@ void ScriptsBuilderImpl::sourceDirEvent(const String& path, FileSystemAction act
     // Discard non-source files or generated files
     if ((!path.EndsWith(TEXT(".cs")) &&
         !path.EndsWith(TEXT(".cpp")) &&
+        !path.EndsWith(TEXT(".c")) &&
+        !path.EndsWith(TEXT(".hpp")) &&
         !path.EndsWith(TEXT(".h"))) ||
         path.EndsWith(TEXT(".Gen.cs")))
+    {
         return;
+    }
 
     ScopeLock scopeLock(_locker);
     _lastSourceCodeEdited = DateTime::Now();
@@ -272,7 +277,7 @@ bool ScriptsBuilder::GenerateProject(const StringView& customArgs)
     return RunBuildTool(args);
 }
 
-void ScriptsBuilderImpl::GetClassName(const StringAnsi& fullname, StringAnsi& className)
+void ScriptsBuilderImpl::GetClassName(const StringAnsiView fullname, StringAnsi& className)
 {
     const auto lastDotIndex = fullname.FindLast('.');
     if (lastDotIndex != -1)
@@ -413,6 +418,7 @@ void ScriptsBuilder::GetBinariesConfiguration(const Char*& target, const Char*&
 
 bool ScriptsBuilderImpl::compileGameScriptsAsyncInner()
 {
+    PROFILE_MEM(Editor);
     LOG(Info, "Starting scripts compilation...");
     CallEvent(EventType::CompileStarted);
 
@@ -519,6 +525,8 @@ void ScriptsBuilderImpl::onEditorAssemblyUnloading(MAssembly* assembly)
 
 bool ScriptsBuilderImpl::compileGameScriptsAsync()
 {
+    PROFILE_MEM(Editor);
+
     // Start
     {
         ScopeLock scopeLock(_locker);
@@ -562,6 +570,7 @@ bool ScriptsBuilderService::Init()
     // Check flag
     if (_isInited)
         return false;
+    PROFILE_MEM(Editor);
     _isInited = true;
 
     // Link for Editor assembly unload event to clear cached Internal_OnCompilationEnd to prevent errors
@@ -659,6 +668,9 @@ bool ScriptsBuilderService::Init()
 
 void ScriptsBuilderService::Update()
 {
+    PROFILE_CPU();
+    PROFILE_MEM(Editor);
+
     // Send compilation events
     {
         ScopeLock scopeLock(_compileEventsLocker);

Source/Editor/Surface/Archetypes/Animation.MultiBlend.cs

@@ -233,6 +233,8 @@ namespace FlaxEditor.Surface.Archetypes
         public BlendPointsEditor(Animation.MultiBlend node, bool is2D, float x, float y, float width, float height)
         : base(x, y, width, height)
         {
+            AutoFocus = true;
+
             _node = node;
             _is2D = is2D;
         }

Source/Editor/Surface/Archetypes/Material.cs

@@ -6,6 +6,7 @@ using FlaxEditor.Scripting;
 using FlaxEditor.Surface.Elements;
 using FlaxEditor.Windows.Assets;
 using FlaxEngine;
+using FlaxEngine.GUI;
 
 namespace FlaxEditor.Surface.Archetypes
 {
@@ -123,7 +124,8 @@ namespace FlaxEditor.Surface.Archetypes
                 case MaterialDomain.Particle:
                 case MaterialDomain.Deformable:
                 {
-                    bool isNotUnlit = info.ShadingModel != MaterialShadingModel.Unlit;
+                    bool isNotUnlit = info.ShadingModel != MaterialShadingModel.Unlit && info.ShadingModel != MaterialShadingModel.CustomLit;
+                    bool isOpaque = info.BlendMode == MaterialBlendMode.Opaque;
                     bool withTess = info.TessellationMode != TessellationMethod.None;
 
                     GetBox(MaterialNodeBoxes.Color).IsActive = isNotUnlit;
@@ -134,8 +136,8 @@ namespace FlaxEditor.Surface.Archetypes
                     GetBox(MaterialNodeBoxes.Roughness).IsActive = isNotUnlit;
                     GetBox(MaterialNodeBoxes.AmbientOcclusion).IsActive = isNotUnlit;
                     GetBox(MaterialNodeBoxes.Normal).IsActive = isNotUnlit;
-                    GetBox(MaterialNodeBoxes.Opacity).IsActive = info.ShadingModel == MaterialShadingModel.Subsurface || info.ShadingModel == MaterialShadingModel.Foliage || info.BlendMode != MaterialBlendMode.Opaque;
-                    GetBox(MaterialNodeBoxes.Refraction).IsActive = info.BlendMode != MaterialBlendMode.Opaque;
+                    GetBox(MaterialNodeBoxes.Opacity).IsActive = info.ShadingModel == MaterialShadingModel.Subsurface || info.ShadingModel == MaterialShadingModel.Foliage || !isOpaque;
+                    GetBox(MaterialNodeBoxes.Refraction).IsActive = !isOpaque;
                     GetBox(MaterialNodeBoxes.PositionOffset).IsActive = true;
                     GetBox(MaterialNodeBoxes.TessellationMultiplier).IsActive = withTess;
                     GetBox(MaterialNodeBoxes.WorldDisplacement).IsActive = withTess;
@@ -260,6 +262,211 @@ namespace FlaxEditor.Surface.Archetypes
             }
         }
 
+#if false // TODO: finish code editor based on RichTextBoxBase with text block parsing for custom styling
+        internal sealed class CustomCodeTextBox : RichTextBoxBase
+        {
+            protected override void OnParseTextBlocks()
+            {
+                base.OnParseTextBlocks();
+
+                // Single block for a whole text
+                // TODO: implement code parsing with HLSL syntax
+                var font = Style.Current.FontMedium;
+                var style = new TextBlockStyle
+                {
+                    Font = new FontReference(font),
+                    Color = Style.Current.Foreground,
+                    BackgroundSelectedBrush = new SolidColorBrush(Style.Current.BackgroundSelected),
+                };
+                _textBlocks.Clear();
+                _textBlocks.Add(new TextBlock
+                {
+                    Range = new TextRange
+                    {
+                        StartIndex = 0,
+                        EndIndex = TextLength,
+                    },
+                    Style = style,
+                    Bounds = new Rectangle(Float2.Zero, font.MeasureText(Text)),
+                });
+            }
+#else
+        internal sealed class CustomCodeTextBox : TextBox
+        {
+#endif
+            public override void Draw()
+            {
+                base.Draw();
+
+                // Draw border
+                if (!IsFocused)
+                    Render2D.DrawRectangle(new Rectangle(Float2.Zero, Size), Style.Current.BorderNormal);
+            }
+        }
+
+        internal sealed class CustomCodeNode : SurfaceNode
+        {
+            private Rectangle _resizeButtonRect;
+            private Float2 _startResizingSize;
+            private Float2 _startResizingCornerOffset;
+            private bool _isResizing;
+            private CustomCodeTextBox _textBox;
+
+            private int SizeValueIndex => Archetype.TypeID == 8 ? 1 : 3; // Index of the Size stored in Values array
+
+            private Float2 SizeValue
+            {
+                get => (Float2)Values[SizeValueIndex];
+                set => SetValue(SizeValueIndex, value, false);
+            }
+
+            public CustomCodeNode(uint id, VisjectSurfaceContext context, NodeArchetype nodeArch, GroupArchetype groupArch)
+            : base(id, context, nodeArch, groupArch)
+            {
+                Float2 pos = new Float2(FlaxEditor.Surface.Constants.NodeMarginX, FlaxEditor.Surface.Constants.NodeMarginY + FlaxEditor.Surface.Constants.NodeHeaderSize), size;
+                if (nodeArch.TypeID == 8)
+                {
+                    pos += new Float2(60, 0);
+                    size = new Float2(172, 200);
+                }
+                else
+                {
+                    pos += new Float2(0, 40);
+                    size = new Float2(300, 200);
+                }
+                _textBox = new CustomCodeTextBox
+                {
+                    IsMultiline = true,
+                    Location = pos,
+                    Size = size,
+                    Parent = this,
+                    AnchorMax = Float2.One,
+                };
+                _textBox.EditEnd += () => SetValue(0, _textBox.Text);
+            }
+
+            public override bool CanSelect(ref Float2 location)
+            {
+                return base.CanSelect(ref location) && !_resizeButtonRect.MakeOffsetted(Location).Contains(ref location);
+            }
+
+            public override void OnSurfaceLoaded(SurfaceNodeActions action)
+            {
+                base.OnSurfaceLoaded(action);
+
+                _textBox.Text = (string)Values[0];
+
+                var size = SizeValue;
+                if (Surface != null && Surface.GridSnappingEnabled)
+                    size = Surface.SnapToGrid(size, true);
+                Resize(size.X, size.Y);
+            }
+
+            public override void OnValuesChanged()
+            {
+                base.OnValuesChanged();
+
+                var size = SizeValue;
+                Resize(size.X, size.Y);
+                _textBox.Text = (string)Values[0];
+            }
+
+            protected override void UpdateRectangles()
+            {
+                base.UpdateRectangles();
+
+                const float buttonMargin = FlaxEditor.Surface.Constants.NodeCloseButtonMargin;
+                const float buttonSize = FlaxEditor.Surface.Constants.NodeCloseButtonSize;
+                _resizeButtonRect = new Rectangle(_closeButtonRect.Left, Height - buttonSize - buttonMargin - 4, buttonSize, buttonSize);
+            }
+
+            public override void Draw()
+            {
+                base.Draw();
+
+                var style = Style.Current;
+                if (_isResizing)
+                {
+                    Render2D.FillRectangle(_resizeButtonRect, style.Selection);
+                    Render2D.DrawRectangle(_resizeButtonRect, style.SelectionBorder);
+                }
+                Render2D.DrawSprite(style.Scale, _resizeButtonRect, _resizeButtonRect.Contains(_mousePosition) && Surface.CanEdit ? style.Foreground : style.ForegroundGrey);
+            }
+
+            public override void OnLostFocus()
+            {
+                if (_isResizing)
+                    EndResizing();
+
+                base.OnLostFocus();
+            }
+
+            public override void OnEndMouseCapture()
+            {
+                if (_isResizing)
+                    EndResizing();
+
+                base.OnEndMouseCapture();
+            }
+
+            public override bool OnMouseDown(Float2 location, MouseButton button)
+            {
+                if (base.OnMouseDown(location, button))
+                    return true;
+
+                if (button == MouseButton.Left && _resizeButtonRect.Contains(ref location) && Surface.CanEdit)
+                {
+                    // Start sliding
+                    _isResizing = true;
+                    _startResizingSize = Size;
+                    _startResizingCornerOffset = Size - location;
+                    StartMouseCapture();
+                    Cursor = CursorType.SizeNWSE;
+                    return true;
+                }
+
+                return false;
+            }
+
+            public override void OnMouseMove(Float2 location)
+            {
+                if (_isResizing)
+                {
+                    var emptySize = CalculateNodeSize(0, 0);
+                    var size = Float2.Max(location - emptySize + _startResizingCornerOffset, new Float2(240, 160));
+                    Resize(size.X, size.Y);
+                }
+                else
+                {
+                    base.OnMouseMove(location);
+                }
+            }
+
+            public override bool OnMouseUp(Float2 location, MouseButton button)
+            {
+                if (button == MouseButton.Left && _isResizing)
+                {
+                    EndResizing();
+                    return true;
+                }
+
+                return base.OnMouseUp(location, button);
+            }
+
+            private void EndResizing()
+            {
+                Cursor = CursorType.Default;
+                EndMouseCapture();
+                _isResizing = false;
+                if (_startResizingSize != Size)
+                {
+                    var emptySize = CalculateNodeSize(0, 0);
+                    SizeValue = Size - emptySize;
+                    Surface.MarkAsEdited(false);
+                }
+            }
+        }
+
         internal enum MaterialTemplateInputsMapping
         {
             /// <summary>
@@ -410,13 +617,15 @@ namespace FlaxEditor.Surface.Archetypes
             new NodeArchetype
             {
                 TypeID = 8,
+                Create = (id, context, arch, groupArch) => new CustomCodeNode(id, context, arch, groupArch),
                 Title = "Custom Code",
                 Description = "Custom HLSL shader code expression",
                 Flags = NodeFlags.MaterialGraph,
                 Size = new Float2(300, 200),
                 DefaultValues = new object[]
                 {
-                    "// Here you can add HLSL code\nOutput0 = Input0;"
+                    "// Here you can add HLSL code\nOutput0 = Input0;",
+                    new Float2(300, 200),
                 },
                 Elements = new[]
                 {
@@ -433,8 +642,6 @@ namespace FlaxEditor.Surface.Archetypes
                     NodeElementArchetype.Factory.Output(1, "Output1", typeof(Float4), 9),
                     NodeElementArchetype.Factory.Output(2, "Output2", typeof(Float4), 10),
                     NodeElementArchetype.Factory.Output(3, "Output3", typeof(Float4), 11),
-
-                    NodeElementArchetype.Factory.TextBox(60, 0, 175, 200, 0),
                 }
             },
             new NodeArchetype
@@ -874,6 +1081,7 @@ namespace FlaxEditor.Surface.Archetypes
             new NodeArchetype
             {
                 TypeID = 38,
+                Create = (id, context, arch, groupArch) => new CustomCodeNode(id, context, arch, groupArch),
                 Title = "Custom Global Code",
                 Description = "Custom global HLSL shader code expression (placed before material shader code). Can contain includes to shader utilities or declare functions to reuse later.",
                 Flags = NodeFlags.MaterialGraph,
@@ -883,6 +1091,7 @@ namespace FlaxEditor.Surface.Archetypes
                     "// Here you can add HLSL code\nfloat4 GetCustomColor()\n{\n\treturn float4(1, 0, 0, 1);\n}",
                     true,
                     (int)MaterialTemplateInputsMapping.Utilities,
+                    new Float2(300, 240),
                 },
                 Elements = new[]
                 {
@@ -890,7 +1099,6 @@ namespace FlaxEditor.Surface.Archetypes
                     NodeElementArchetype.Factory.Text(20, 0, "Enabled"),
                     NodeElementArchetype.Factory.Text(0, 20, "Location"),
                     NodeElementArchetype.Factory.Enum(50, 20, 120, 2, typeof(MaterialTemplateInputsMapping)),
-                    NodeElementArchetype.Factory.TextBox(0, 40, 300, 200, 0),
                 }
             },
             new NodeArchetype

Source/Editor/Surface/Archetypes/Tools.cs

@@ -1390,7 +1390,7 @@ namespace FlaxEditor.Surface.Archetypes
                 Elements = new[]
                 {
                     NodeElementArchetype.Factory.Output(0, "Time", typeof(float), 0),
-                    NodeElementArchetype.Factory.Output(1, "Unscaled Time", typeof(float), 1),
+                    NodeElementArchetype.Factory.Output(1, "Scaled Time", typeof(float), 1),
                 }
             },
             new NodeArchetype

Source/Editor/Surface/ContextMenu/VisjectCM.cs

@@ -412,7 +412,7 @@ namespace FlaxEditor.Surface.ContextMenu
                 {
                     group.UnlockChildrenRecursive();
                     // TODO: Improve filtering to be based on boxes with the most common things instead of first box
-                    if (_contextSensitiveSearchEnabled && _selectedBoxes[0] != null)
+                    if (_contextSensitiveSearchEnabled && _selectedBoxes.Count > 0 && _selectedBoxes[0] != null)
                         UpdateFilters();
                     else
                         SortGroups();
@@ -424,7 +424,7 @@ namespace FlaxEditor.Surface.ContextMenu
                         OnSearchFilterChanged();
                     }
                 }
-                else if (_contextSensitiveSearchEnabled)
+                else if (_contextSensitiveSearchEnabled && _selectedBoxes.Count > 0)
                 {
                     // TODO: Filtering could be improved here as well
                     group.EvaluateVisibilityWithBox(_selectedBoxes[0]);
@@ -462,7 +462,7 @@ namespace FlaxEditor.Surface.ContextMenu
                             Parent = group
                         };
                     }
-                    if (_contextSensitiveSearchEnabled)
+                    if (_contextSensitiveSearchEnabled && _selectedBoxes.Count > 0)
                         group.EvaluateVisibilityWithBox(_selectedBoxes[0]);
                     group.SortChildren();
                     if (ShowExpanded)
@@ -476,7 +476,7 @@ namespace FlaxEditor.Surface.ContextMenu
 
                 if (!isLayoutLocked)
                 {
-                    if (_contextSensitiveSearchEnabled && _selectedBoxes[0] != null)
+                    if (_contextSensitiveSearchEnabled && _selectedBoxes.Count != 0 && _selectedBoxes[0] != null)
                         UpdateFilters();
                     else
                         SortGroups();