Implement the ability to disable classes

* This PR adds the ability to disable classes when building.
* For now it's only possible to do this via command like:
  `scons disable_classes=RayCast2D,Area3D`
* Eventually, a proper UI will be implemented to create a build config file to do this at large scale, as well as detect what is used in the project.

SConstruct

@@ -142,6 +142,7 @@ opts.Add("extra_suffix", "Custom extra suffix added to the base filename of all
 opts.Add(BoolVariable("vsproj", "Generate a Visual Studio solution", False))
 opts.Add(BoolVariable("disable_3d", "Disable 3D nodes for a smaller executable", False))
 opts.Add(BoolVariable("disable_advanced_gui", "Disable advanced GUI nodes and behaviors", False))
+opts.Add("disable_classes", "Disable given classes (comma separated)", "")
 opts.Add(BoolVariable("modules_enabled_by_default", "If no, disable all modules except ones explicitly enabled", True))
 opts.Add(BoolVariable("no_editor_splash", "Don't use the custom splash screen for the editor", False))
 opts.Add("system_certs_path", "Use this path as SSL certificates default for editor (for package maintainers)", "")
@@ -642,6 +643,7 @@ if selected_platform in platform_list:
 
     if env["tools"]:
         env.Append(CPPDEFINES=["TOOLS_ENABLED"])
+    methods.write_disabled_classes(env["disable_classes"].split(","))
     if env["disable_3d"]:
         if env["tools"]:
             print(

core/object/class_db.h

@@ -434,4 +434,15 @@ class ClassDB {
 
 #endif
 
+#define GDREGISTER_CLASS(m_class)                    \
+	if (!GD_IS_DEFINED(ClassDB_Disable_##m_class)) { \
+		ClassDB::register_class<m_class>();          \
+	}
+#define GDREGISTER_VIRTUAL_CLASS(m_class)            \
+	if (!GD_IS_DEFINED(ClassDB_Disable_##m_class)) { \
+		ClassDB::register_virtual_class<m_class>();  \
+	}
+
+#include "core/disabled_classes.gen.h"
+
 #endif // CLASS_DB_H

core/register_core_types.cpp

@@ -131,50 +131,50 @@ void register_core_types() {
 	resource_format_image.instantiate();
 	ResourceLoader::add_resource_format_loader(resource_format_image);
 
-	ClassDB::register_class<Object>();
-
-	ClassDB::register_virtual_class<Script>();
-
-	ClassDB::register_class<RefCounted>();
-	ClassDB::register_class<WeakRef>();
-	ClassDB::register_class<Resource>();
-	ClassDB::register_class<Image>();
-
-	ClassDB::register_virtual_class<InputEvent>();
-	ClassDB::register_virtual_class<InputEventWithModifiers>();
-	ClassDB::register_virtual_class<InputEventFromWindow>();
-	ClassDB::register_class<InputEventKey>();
-	ClassDB::register_virtual_class<InputEventMouse>();
-	ClassDB::register_class<InputEventMouseButton>();
-	ClassDB::register_class<InputEventMouseMotion>();
-	ClassDB::register_class<InputEventJoypadButton>();
-	ClassDB::register_class<InputEventJoypadMotion>();
-	ClassDB::register_class<InputEventScreenDrag>();
-	ClassDB::register_class<InputEventScreenTouch>();
-	ClassDB::register_class<InputEventAction>();
-	ClassDB::register_virtual_class<InputEventGesture>();
-	ClassDB::register_class<InputEventMagnifyGesture>();
-	ClassDB::register_class<InputEventPanGesture>();
-	ClassDB::register_class<InputEventMIDI>();
+	GDREGISTER_CLASS(Object);
+
+	GDREGISTER_VIRTUAL_CLASS(Script);
+
+	GDREGISTER_CLASS(RefCounted);
+	GDREGISTER_CLASS(WeakRef);
+	GDREGISTER_CLASS(Resource);
+	GDREGISTER_CLASS(Image);
+
+	GDREGISTER_VIRTUAL_CLASS(InputEvent);
+	GDREGISTER_VIRTUAL_CLASS(InputEventWithModifiers);
+	GDREGISTER_VIRTUAL_CLASS(InputEventFromWindow);
+	GDREGISTER_CLASS(InputEventKey);
+	GDREGISTER_VIRTUAL_CLASS(InputEventMouse);
+	GDREGISTER_CLASS(InputEventMouseButton);
+	GDREGISTER_CLASS(InputEventMouseMotion);
+	GDREGISTER_CLASS(InputEventJoypadButton);
+	GDREGISTER_CLASS(InputEventJoypadMotion);
+	GDREGISTER_CLASS(InputEventScreenDrag);
+	GDREGISTER_CLASS(InputEventScreenTouch);
+	GDREGISTER_CLASS(InputEventAction);
+	GDREGISTER_VIRTUAL_CLASS(InputEventGesture);
+	GDREGISTER_CLASS(InputEventMagnifyGesture);
+	GDREGISTER_CLASS(InputEventPanGesture);
+	GDREGISTER_CLASS(InputEventMIDI);
 
 	// Network
-	ClassDB::register_virtual_class<IP>();
+	GDREGISTER_VIRTUAL_CLASS(IP);
 
-	ClassDB::register_virtual_class<StreamPeer>();
-	ClassDB::register_class<StreamPeerBuffer>();
-	ClassDB::register_class<StreamPeerTCP>();
-	ClassDB::register_class<TCPServer>();
+	GDREGISTER_VIRTUAL_CLASS(StreamPeer);
+	GDREGISTER_CLASS(StreamPeerBuffer);
+	GDREGISTER_CLASS(StreamPeerTCP);
+	GDREGISTER_CLASS(TCPServer);
 
-	ClassDB::register_virtual_class<PacketPeer>();
-	ClassDB::register_class<PacketPeerStream>();
-	ClassDB::register_class<PacketPeerUDP>();
-	ClassDB::register_class<UDPServer>();
+	GDREGISTER_VIRTUAL_CLASS(PacketPeer);
+	GDREGISTER_CLASS(PacketPeerStream);
+	GDREGISTER_CLASS(PacketPeerUDP);
+	GDREGISTER_CLASS(UDPServer);
 
 	ClassDB::register_custom_instance_class<HTTPClient>();
 
 	// Crypto
-	ClassDB::register_class<HashingContext>();
-	ClassDB::register_class<AESContext>();
+	GDREGISTER_CLASS(HashingContext);
+	GDREGISTER_CLASS(AESContext);
 	ClassDB::register_custom_instance_class<X509Certificate>();
 	ClassDB::register_custom_instance_class<CryptoKey>();
 	ClassDB::register_custom_instance_class<HMACContext>();
@@ -188,42 +188,42 @@ void register_core_types() {
 	resource_format_loader_crypto.instantiate();
 	ResourceLoader::add_resource_format_loader(resource_format_loader_crypto);
 
-	ClassDB::register_virtual_class<MultiplayerPeer>();
-	ClassDB::register_class<MultiplayerAPI>();
-	ClassDB::register_class<MainLoop>();
-	ClassDB::register_class<Translation>();
-	ClassDB::register_class<OptimizedTranslation>();
-	ClassDB::register_class<UndoRedo>();
-	ClassDB::register_class<TriangleMesh>();
+	GDREGISTER_VIRTUAL_CLASS(MultiplayerPeer);
+	GDREGISTER_CLASS(MultiplayerAPI);
+	GDREGISTER_CLASS(MainLoop);
+	GDREGISTER_CLASS(Translation);
+	GDREGISTER_CLASS(OptimizedTranslation);
+	GDREGISTER_CLASS(UndoRedo);
+	GDREGISTER_CLASS(TriangleMesh);
 
-	ClassDB::register_class<ResourceFormatLoader>();
-	ClassDB::register_class<ResourceFormatSaver>();
+	GDREGISTER_CLASS(ResourceFormatLoader);
+	GDREGISTER_CLASS(ResourceFormatSaver);
 
-	ClassDB::register_class<_File>();
-	ClassDB::register_class<_Directory>();
-	ClassDB::register_class<_Thread>();
-	ClassDB::register_class<_Mutex>();
-	ClassDB::register_class<_Semaphore>();
+	GDREGISTER_CLASS(_File);
+	GDREGISTER_CLASS(_Directory);
+	GDREGISTER_CLASS(_Thread);
+	GDREGISTER_CLASS(_Mutex);
+	GDREGISTER_CLASS(_Semaphore);
 
-	ClassDB::register_class<XMLParser>();
-	ClassDB::register_class<JSON>();
+	GDREGISTER_CLASS(XMLParser);
+	GDREGISTER_CLASS(JSON);
 
-	ClassDB::register_class<ConfigFile>();
+	GDREGISTER_CLASS(ConfigFile);
 
-	ClassDB::register_class<PCKPacker>();
+	GDREGISTER_CLASS(PCKPacker);
 
-	ClassDB::register_class<PackedDataContainer>();
-	ClassDB::register_virtual_class<PackedDataContainerRef>();
-	ClassDB::register_class<AStar>();
-	ClassDB::register_class<AStar2D>();
-	ClassDB::register_class<EncodedObjectAsID>();
-	ClassDB::register_class<RandomNumberGenerator>();
+	GDREGISTER_CLASS(PackedDataContainer);
+	GDREGISTER_VIRTUAL_CLASS(PackedDataContainerRef);
+	GDREGISTER_CLASS(AStar);
+	GDREGISTER_CLASS(AStar2D);
+	GDREGISTER_CLASS(EncodedObjectAsID);
+	GDREGISTER_CLASS(RandomNumberGenerator);
 
-	ClassDB::register_virtual_class<ResourceImporter>();
+	GDREGISTER_VIRTUAL_CLASS(ResourceImporter);
 
-	ClassDB::register_class<NativeExtension>();
+	GDREGISTER_CLASS(NativeExtension);
 
-	ClassDB::register_virtual_class<NativeExtensionManager>();
+	GDREGISTER_VIRTUAL_CLASS(NativeExtensionManager);
 
 	native_extension_manager = memnew(NativeExtensionManager);
 
@@ -253,22 +253,22 @@ void register_core_settings() {
 }
 
 void register_core_singletons() {
-	ClassDB::register_class<ProjectSettings>();
-	ClassDB::register_virtual_class<IP>();
-	ClassDB::register_class<_Geometry2D>();
-	ClassDB::register_class<_Geometry3D>();
-	ClassDB::register_class<_ResourceLoader>();
-	ClassDB::register_class<_ResourceSaver>();
-	ClassDB::register_class<_OS>();
-	ClassDB::register_class<_Engine>();
-	ClassDB::register_class<_ClassDB>();
-	ClassDB::register_class<_Marshalls>();
-	ClassDB::register_class<TranslationServer>();
-	ClassDB::register_virtual_class<Input>();
-	ClassDB::register_class<InputMap>();
-	ClassDB::register_class<Expression>();
-	ClassDB::register_class<_EngineDebugger>();
-	ClassDB::register_class<Time>();
+	GDREGISTER_CLASS(ProjectSettings);
+	GDREGISTER_VIRTUAL_CLASS(IP);
+	GDREGISTER_CLASS(_Geometry2D);
+	GDREGISTER_CLASS(_Geometry3D);
+	GDREGISTER_CLASS(_ResourceLoader);
+	GDREGISTER_CLASS(_ResourceSaver);
+	GDREGISTER_CLASS(_OS);
+	GDREGISTER_CLASS(_Engine);
+	GDREGISTER_CLASS(_ClassDB);
+	GDREGISTER_CLASS(_Marshalls);
+	GDREGISTER_CLASS(TranslationServer);
+	GDREGISTER_VIRTUAL_CLASS(Input);
+	GDREGISTER_CLASS(InputMap);
+	GDREGISTER_CLASS(Expression);
+	GDREGISTER_CLASS(_EngineDebugger);
+	GDREGISTER_CLASS(Time);
 
 	Engine::get_singleton()->add_singleton(Engine::Singleton("ProjectSettings", ProjectSettings::get_singleton()));
 	Engine::get_singleton()->add_singleton(Engine::Singleton("IP", IP::get_singleton(), "IP"));

core/typedefs.h

@@ -281,4 +281,11 @@ struct BuildIndexSequence<0, Is...> : IndexSequence<Is...> {};
 #define DEBUG_METHODS_ENABLED
 #endif
 
+// Macro GD_IS_DEFINED() allows to check if a macro is defined. It needs to be defined to anything (say 1) to work.
+#define __GDARG_PLACEHOLDER_1 0,
+#define __gd_take_second_arg(__ignored, val, ...) val
+#define ____gd_is_defined(arg1_or_junk) __gd_take_second_arg(arg1_or_junk 1, 0)
+#define ___gd_is_defined(val) ____gd_is_defined(__GDARG_PLACEHOLDER_##val)
+#define GD_IS_DEFINED(x) ___gd_is_defined(x)
+
 #endif // TYPEDEFS_H

editor/editor_node.cpp

@@ -3736,46 +3736,46 @@ void EditorNode::register_editor_types() {
 	ResourceLoader::set_timestamp_on_load(true);
 	ResourceSaver::set_timestamp_on_save(true);
 
-	ClassDB::register_class<EditorPaths>();
-	ClassDB::register_class<EditorPlugin>();
-	ClassDB::register_class<EditorTranslationParserPlugin>();
-	ClassDB::register_class<EditorImportPlugin>();
-	ClassDB::register_class<EditorScript>();
-	ClassDB::register_class<EditorSelection>();
-	ClassDB::register_class<EditorFileDialog>();
-	ClassDB::register_virtual_class<EditorSettings>();
-	ClassDB::register_class<EditorNode3DGizmo>();
-	ClassDB::register_class<EditorNode3DGizmoPlugin>();
-	ClassDB::register_virtual_class<EditorResourcePreview>();
-	ClassDB::register_class<EditorResourcePreviewGenerator>();
-	ClassDB::register_virtual_class<EditorFileSystem>();
-	ClassDB::register_class<EditorFileSystemDirectory>();
-	ClassDB::register_class<EditorVCSInterface>();
-	ClassDB::register_virtual_class<ScriptEditor>();
-	ClassDB::register_virtual_class<ScriptEditorBase>();
-	ClassDB::register_class<EditorSyntaxHighlighter>();
-	ClassDB::register_virtual_class<EditorInterface>();
-	ClassDB::register_class<EditorExportPlugin>();
-	ClassDB::register_class<EditorResourceConversionPlugin>();
-	ClassDB::register_class<EditorSceneImporter>();
-	ClassDB::register_class<EditorInspector>();
-	ClassDB::register_class<EditorInspectorPlugin>();
-	ClassDB::register_class<EditorProperty>();
-	ClassDB::register_class<AnimationTrackEditPlugin>();
-	ClassDB::register_class<ScriptCreateDialog>();
-	ClassDB::register_class<EditorFeatureProfile>();
-	ClassDB::register_class<EditorSpinSlider>();
-	ClassDB::register_class<EditorResourcePicker>();
-	ClassDB::register_class<EditorScriptPicker>();
-	ClassDB::register_class<EditorSceneImporterMesh>();
-	ClassDB::register_class<EditorSceneImporterMeshNode3D>();
-
-	ClassDB::register_virtual_class<FileSystemDock>();
+	GDREGISTER_CLASS(EditorPaths);
+	GDREGISTER_CLASS(EditorPlugin);
+	GDREGISTER_CLASS(EditorTranslationParserPlugin);
+	GDREGISTER_CLASS(EditorImportPlugin);
+	GDREGISTER_CLASS(EditorScript);
+	GDREGISTER_CLASS(EditorSelection);
+	GDREGISTER_CLASS(EditorFileDialog);
+	GDREGISTER_VIRTUAL_CLASS(EditorSettings);
+	GDREGISTER_CLASS(EditorNode3DGizmo);
+	GDREGISTER_CLASS(EditorNode3DGizmoPlugin);
+	GDREGISTER_VIRTUAL_CLASS(EditorResourcePreview);
+	GDREGISTER_CLASS(EditorResourcePreviewGenerator);
+	GDREGISTER_VIRTUAL_CLASS(EditorFileSystem);
+	GDREGISTER_CLASS(EditorFileSystemDirectory);
+	GDREGISTER_CLASS(EditorVCSInterface);
+	GDREGISTER_VIRTUAL_CLASS(ScriptEditor);
+	GDREGISTER_VIRTUAL_CLASS(ScriptEditorBase);
+	GDREGISTER_CLASS(EditorSyntaxHighlighter);
+	GDREGISTER_VIRTUAL_CLASS(EditorInterface);
+	GDREGISTER_CLASS(EditorExportPlugin);
+	GDREGISTER_CLASS(EditorResourceConversionPlugin);
+	GDREGISTER_CLASS(EditorSceneImporter);
+	GDREGISTER_CLASS(EditorInspector);
+	GDREGISTER_CLASS(EditorInspectorPlugin);
+	GDREGISTER_CLASS(EditorProperty);
+	GDREGISTER_CLASS(AnimationTrackEditPlugin);
+	GDREGISTER_CLASS(ScriptCreateDialog);
+	GDREGISTER_CLASS(EditorFeatureProfile);
+	GDREGISTER_CLASS(EditorSpinSlider);
+	GDREGISTER_CLASS(EditorResourcePicker);
+	GDREGISTER_CLASS(EditorScriptPicker);
+	GDREGISTER_CLASS(EditorSceneImporterMesh);
+	GDREGISTER_CLASS(EditorSceneImporterMeshNode3D);
+
+	GDREGISTER_VIRTUAL_CLASS(FileSystemDock);
 
 	// FIXME: Is this stuff obsolete, or should it be ported to new APIs?
-	ClassDB::register_class<EditorScenePostImport>();
+	GDREGISTER_CLASS(EditorScenePostImport);
 	//ClassDB::register_type<EditorImportExport>();
-	ClassDB::register_class<EditorDebuggerPlugin>();
+	GDREGISTER_CLASS(EditorDebuggerPlugin);
 
 	NativeExtensionManager::get_singleton()->initialize_extensions(NativeExtension::INITIALIZATION_LEVEL_EDITOR);
 }

editor/editor_settings.cpp

@@ -884,7 +884,7 @@ void EditorSettings::create() {
 		return;
 	}
 
-	ClassDB::register_class<EditorSettings>(); // Otherwise it can't be unserialized.
+	GDREGISTER_CLASS(EditorSettings); // Otherwise it can't be unserialized.
 
 	String config_file_path;
 	Ref<ConfigFile> extra_config = memnew(ConfigFile);

main/main.cpp

@@ -549,7 +549,7 @@ Error Main::setup(const char *execpath, int argc, char *argv[], bool p_second_ph
 
 	translation_server = memnew(TranslationServer);
 	performance = memnew(Performance);
-	ClassDB::register_class<Performance>();
+	GDREGISTER_CLASS(Performance);
 	engine->add_singleton(Engine::Singleton("Performance", performance));
 
 	// Only flush stdout in debug builds by default, as spamming `print()` will

methods.py

@@ -231,6 +231,18 @@ def is_module(path):
     return True
 
 
+def write_disabled_classes(class_list):
+    f = open("core/disabled_classes.gen.h", "w")
+    f.write("/* THIS FILE IS GENERATED DO NOT EDIT */\n")
+    f.write("#ifndef DISABLED_CLASSES_GEN_H\n")
+    f.write("#define DISABLED_CLASSES_GEN_H\n\n")
+    for c in class_list:
+        cs = c.strip()
+        if cs != "":
+            f.write("#define ClassDB_Disable_" + cs + " 1\n")
+    f.write("\n#endif\n")
+
+
 def write_modules(modules):
     includes_cpp = ""
     preregister_cpp = ""

modules/basis_universal/register_types.cpp

@@ -272,7 +272,7 @@ void register_basis_universal_types() {
 	Image::basis_universal_packer = basis_universal_packer;
 #endif
 	Image::basis_universal_unpacker = basis_universal_unpacker;
-	//ClassDB::register_class<TextureBasisU>();
+	//GDREGISTER_CLASS(TextureBasisU);
 }
 
 void unregister_basis_universal_types() {

modules/csg/register_types.cpp

@@ -36,15 +36,15 @@
 void register_csg_types() {
 #ifndef _3D_DISABLED
 
-	ClassDB::register_virtual_class<CSGShape3D>();
-	ClassDB::register_virtual_class<CSGPrimitive3D>();
-	ClassDB::register_class<CSGMesh3D>();
-	ClassDB::register_class<CSGSphere3D>();
-	ClassDB::register_class<CSGBox3D>();
-	ClassDB::register_class<CSGCylinder3D>();
-	ClassDB::register_class<CSGTorus3D>();
-	ClassDB::register_class<CSGPolygon3D>();
-	ClassDB::register_class<CSGCombiner3D>();
+	GDREGISTER_VIRTUAL_CLASS(CSGShape3D);
+	GDREGISTER_VIRTUAL_CLASS(CSGPrimitive3D);
+	GDREGISTER_CLASS(CSGMesh3D);
+	GDREGISTER_CLASS(CSGSphere3D);
+	GDREGISTER_CLASS(CSGBox3D);
+	GDREGISTER_CLASS(CSGCylinder3D);
+	GDREGISTER_CLASS(CSGTorus3D);
+	GDREGISTER_CLASS(CSGPolygon3D);
+	GDREGISTER_CLASS(CSGCombiner3D);
 
 #ifdef TOOLS_ENABLED
 	EditorPlugins::add_by_type<EditorPluginCSG>();