Fix support for codeless game projects

Source/Editor/Cooker/Steps/CompileScriptsStep.cpp

@@ -12,6 +12,7 @@
 #include "Editor/Cooker/PlatformTools.h"
 #include "Editor/Editor.h"
 #include "Editor/ProjectInfo.h"
+#include "Engine/Engine/Globals.h"
 
 bool CompileScriptsStep::DeployBinaries(CookingData& data, const String& path, const String& projectFolderPath)
 {
@@ -136,12 +137,8 @@ bool CompileScriptsStep::Perform(CookingData& data)
     data.StepProgress(TEXT("Compiling game scripts"), 0);
 
     const ProjectInfo* project = Editor::Project;
-    const String& target = project->GameTarget;
-    if (target.IsEmpty())
-    {
-        LOG(Error, "Empty GameTarget in project.");
-        return true;
-    }
+    String target = project->GameTarget;
+    StringView workingDir;
     const Char *platform, *architecture, *configuration = ::ToString(data.Configuration);
     switch (data.Platform)
     {
@@ -189,6 +186,15 @@ bool CompileScriptsStep::Perform(CookingData& data)
         LOG(Error, "Unknown or unsupported build platform.");
         return true;
     }
+    String targetBuildInfo = project->ProjectFolderPath / TEXT("Binaries") / target / platform / architecture / configuration / target + TEXT(".Build.json");
+    if (target.IsEmpty())
+    {
+        // Fallback to engine-only if game has no code
+        LOG(Warning, "Empty GameTarget in project.");
+        target = TEXT("FlaxGame");
+        workingDir = Globals::StartupFolder;
+        targetBuildInfo = Globals::StartupFolder / TEXT("Source/Platforms") / platform / TEXT("Binaries") / TEXT("Game") / architecture / configuration / target + TEXT(".Build.json");
+    }
     _extensionsToSkip.Clear();
     _extensionsToSkip.Add(TEXT(".exp"));
     _extensionsToSkip.Add(TEXT(".ilk"));
@@ -229,7 +235,7 @@ bool CompileScriptsStep::Perform(CookingData& data)
         args += TEXT(" -D");
         args += define;
     }
-    if (ScriptsBuilder::RunBuildTool(args))
+    if (ScriptsBuilder::RunBuildTool(args, workingDir))
     {
         data.Error(TEXT("Failed to compile game scripts."));
         return true;
@@ -243,7 +249,6 @@ bool CompileScriptsStep::Perform(CookingData& data)
     data.StepProgress(TEXT("Exporting binaries"), 0.8f);
 
     // Deploy binary modules
-    const String targetBuildInfo = project->ProjectFolderPath / TEXT("Binaries") / project->GameTarget / platform / architecture / configuration / target + TEXT(".Build.json");
     if (DeployBinaries(data, targetBuildInfo, project->ProjectFolderPath))
         return true;
 

Source/Editor/Scripting/ScriptsBuilder.cpp

@@ -211,7 +211,7 @@ void ScriptsBuilder::Compile()
     _isCompileRequested = true;
 }
 
-bool ScriptsBuilder::RunBuildTool(const StringView& args)
+bool ScriptsBuilder::RunBuildTool(const StringView& args, const StringView& workingDir)
 {
     PROFILE_CPU();
     const String buildToolPath = Globals::StartupFolder / TEXT("Binaries/Tools/Flax.Build.exe");
@@ -242,7 +242,7 @@ bool ScriptsBuilder::RunBuildTool(const StringView& args)
     // TODO: Set env var for the mono MONO_GC_PARAMS=nursery-size64m to boost build performance -> profile it
 
     // Call build tool
-    const int32 result = Platform::RunProcess(StringView(*cmdLine, cmdLine.Length()), StringView::Empty);
+    const int32 result = Platform::RunProcess(StringView(*cmdLine, cmdLine.Length()), workingDir);
     return result != 0;
 }
 
@@ -357,7 +357,7 @@ void ScriptsBuilder::GetBinariesConfiguration(const Char*& target, const Char*&
     else
     {
         target = TEXT("");
-        LOG(Error, "Missing editor/game targets in project. Please specify EditorTarget and GameTarget properties in .flaxproj file.");
+        LOG(Warning, "Missing editor/game targets in project. Please specify EditorTarget and GameTarget properties in .flaxproj file.");
     }
 
 #if PLATFORM_WINDOWS
@@ -395,7 +395,7 @@ bool ScriptsBuilderImpl::compileGameScriptsAsyncInner()
     // Call compilation
     const Char *target, *platform, *architecture, *configuration;
     ScriptsBuilder::GetBinariesConfiguration(target, platform, architecture, configuration);
-    if (!target)
+    if (StringUtils::Length(target) == 0)
     {
         LOG(Info, "Missing EditorTarget in project. Skipping compilation.");
         CallEvent(EventType::ReloadCalled);
@@ -580,7 +580,7 @@ bool ScriptsBuilderService::Init()
     // Remove any remaining files from previous Editor run hot-reloads
     const Char *target, *platform, *architecture, *configuration;
     ScriptsBuilder::GetBinariesConfiguration(target, platform, architecture, configuration);
-    if (target)
+    if (StringUtils::Length(target) != 0)
     {
         const String targetOutput = Globals::ProjectFolder / TEXT("Binaries") / target / platform / architecture / configuration;
         Array<String> files;

Source/Editor/Scripting/ScriptsBuilder.h

@@ -97,8 +97,9 @@ public:
     /// Invokes the Flax.Build tool in the current project workspace and waits for the process end (blocking). Prints the build tool output to the log. Can be invoked from any thread.
     /// </summary>
     /// <param name="args">The Flax.Build tool invocation arguments.</param>
+    /// <param name="workingDir">The custom working directory. Use empty or null to execute build tool in the project folder.</param>
     /// <returns>True if failed, otherwise false.</returns>
-    API_FUNCTION() static bool RunBuildTool(const StringView& args);
+    API_FUNCTION() static bool RunBuildTool(const StringView& args, const StringView& workingDir = StringView::Empty);
 
     /// <summary>
     /// Generates the project files.

Source/Engine/Scripting/Scripting.cpp

@@ -446,9 +446,10 @@ bool Scripting::Load()
     // Flax.Build outputs the <target>.Build.json with binary modules to use for game scripting
     const Char *target, *platform, *architecture, *configuration;
     ScriptsBuilder::GetBinariesConfiguration(target, platform, architecture, configuration);
-    if (target == nullptr)
+    if (StringUtils::Length(target) == 0)
     {
         LOG(Info, "Missing EditorTarget in project. Not using game script modules.");
+        _hasGameModulesLoaded = true;
         return false;
     }
     const String targetBuildInfo = Globals::ProjectFolder / TEXT("Binaries") / target / platform / architecture / configuration / target + TEXT(".Build.json");