Merge pull request #619 from godot-rust/feature/runtime-classes

For v4.3+, switch `#[class(tool)]` to use Godot's native "runtime class" feature

godot-core/src/private.rs

@@ -30,6 +30,8 @@ pub struct ClassConfig {
     pub is_tool: bool,
 }
 
+// Starting from 4.3, Godot has "runtime classes"; this emulation is no longer needed.
+#[cfg(before_api = "4.3")]
 pub fn is_class_inactive(is_tool: bool) -> bool {
     if is_tool {
         return false;
@@ -43,6 +45,21 @@ pub fn is_class_inactive(is_tool: bool) -> bool {
         && global_config.is_editor_or_init(is_editor)
 }
 
+// Starting from 4.3, Godot has "runtime classes"; we only need to check whether editor is running.
+#[cfg(since_api = "4.3")]
+pub fn is_class_runtime(is_tool: bool) -> bool {
+    if is_tool {
+        return false;
+    }
+
+    // SAFETY: only invoked after global library initialization.
+    let global_config = unsafe { sys::config() };
+
+    // If this is not a #[class(tool)] and we only run tool classes in the editor, then don't run this in editor -> make it a runtime class.
+    // If we run all classes in the editor (!tool_only_in_editor), then it's not a runtime class.
+    global_config.tool_only_in_editor
+}
+
 pub fn print_panic(err: Box<dyn std::any::Any + Send>) {
     if let Some(s) = err.downcast_ref::<&'static str>() {
         print_panic_message(s);

godot-core/src/registry/mod.rs

@@ -94,6 +94,9 @@ pub enum PluginItem {
             ) -> sys::GDExtensionClassCallVirtual,
         >,
 
+        /// Whether `#[class(tool)]` was used.
+        is_tool: bool,
+
         /// Whether `#[class(editor_plugin)]` was used.
         is_editor_plugin: bool,
 
@@ -205,8 +208,11 @@ struct ClassRegistrationInfo {
     /// Godot low-level class creation parameters.
     #[cfg(before_api = "4.2")]
     godot_params: sys::GDExtensionClassCreationInfo,
-    #[cfg(since_api = "4.2")]
+    #[cfg(all(since_api = "4.2", before_api = "4.3"))]
     godot_params: sys::GDExtensionClassCreationInfo2,
+    #[cfg(since_api = "4.3")]
+    godot_params: sys::GDExtensionClassCreationInfo3,
+
     #[allow(dead_code)] // Currently unused; may be useful for diagnostics in the future.
     init_level: InitLevel,
     is_editor_plugin: bool,
@@ -238,6 +244,7 @@ impl ClassRegistrationInfo {
 }
 
 /// Registers a class with static type information.
+// Currently dead code, but will be needed for builder API. Don't remove.
 pub fn register_class<
     T: cap::GodotDefault
         + cap::ImplementsGodotVirtual
@@ -250,27 +257,20 @@ pub fn register_class<
 
     out!("Manually register class {}", std::any::type_name::<T>());
 
+    // This works as long as fields are called the same. May still need individual #[cfg]s for newer fields.
     #[cfg(before_api = "4.2")]
-    let godot_params = sys::GDExtensionClassCreationInfo {
-        to_string_func: Some(callbacks::to_string::<T>),
-        notification_func: Some(callbacks::on_notification::<T>),
-        reference_func: Some(callbacks::reference::<T>),
-        unreference_func: Some(callbacks::unreference::<T>),
-        create_instance_func: Some(callbacks::create::<T>),
-        free_instance_func: Some(callbacks::free::<T>),
-        get_virtual_func: Some(callbacks::get_virtual::<T>),
-        get_rid_func: None,
-        class_userdata: ptr::null_mut(), // will be passed to create fn, but global per class
-        ..default_creation_info()
-    };
-    #[cfg(since_api = "4.2")]
-    let godot_params = sys::GDExtensionClassCreationInfo2 {
+    type CreationInfo = sys::GDExtensionClassCreationInfo;
+    #[cfg(all(since_api = "4.2", before_api = "4.3"))]
+    type CreationInfo = sys::GDExtensionClassCreationInfo2;
+    #[cfg(since_api = "4.3")]
+    type CreationInfo = sys::GDExtensionClassCreationInfo3;
+
+    let godot_params = CreationInfo {
         to_string_func: Some(callbacks::to_string::<T>),
         notification_func: Some(callbacks::on_notification::<T>),
         reference_func: Some(callbacks::reference::<T>),
         unreference_func: Some(callbacks::unreference::<T>),
         create_instance_func: Some(callbacks::create::<T>),
-        recreate_instance_func: Some(callbacks::recreate::<T>),
         free_instance_func: Some(callbacks::free::<T>),
         get_virtual_func: Some(callbacks::get_virtual::<T>),
         get_rid_func: None,
@@ -384,11 +384,15 @@ fn fill_class_info(item: PluginItem, c: &mut ClassRegistrationInfo) {
             register_properties_fn,
             free_fn,
             default_get_virtual_fn,
+            is_tool,
             is_editor_plugin,
             is_hidden,
             is_instantiable,
         } => {
             c.parent_class_name = Some(base_class_name);
+            c.default_virtual_fn = default_get_virtual_fn;
+            c.register_properties_fn = Some(register_properties_fn);
+            c.is_editor_plugin = is_editor_plugin;
 
             // Classes marked #[class(no_init)] are translated to "abstract" in Godot. This disables their default constructor.
             // "Abstract" is a misnomer -- it's not an abstract base class, but rather a "utility/static class" (although it can have instance
@@ -399,6 +403,7 @@ fn fill_class_info(item: PluginItem, c: &mut ClassRegistrationInfo) {
             //
             // See also: https://github.com/godotengine/godot/pull/58972
             c.godot_params.is_abstract = (!is_instantiable) as sys::GDExtensionBool;
+            c.godot_params.free_instance_func = Some(free_fn);
 
             fill_into(
                 &mut c.godot_params.create_instance_func,
@@ -420,11 +425,11 @@ fn fill_class_info(item: PluginItem, c: &mut ClassRegistrationInfo) {
             #[cfg(before_api = "4.2")]
             assert!(generated_recreate_fn.is_none()); // not used
 
-            c.godot_params.free_instance_func = Some(free_fn);
-            c.default_virtual_fn = default_get_virtual_fn;
-            c.register_properties_fn = Some(register_properties_fn);
-
-            c.is_editor_plugin = is_editor_plugin;
+            #[cfg(since_api = "4.3")]
+            {
+                c.godot_params.is_runtime =
+                    crate::private::is_class_runtime(is_tool) as sys::GDExtensionBool;
+            }
         }
 
         PluginItem::InherentImpl {
@@ -494,29 +499,35 @@ fn register_class_raw(mut info: ClassRegistrationInfo) {
         info.godot_params.get_virtual_func = info.user_virtual_fn.or(info.default_virtual_fn);
     }
 
+    // The explicit () type notifies us if Godot API ever adds a return type.
+    #[allow(clippy::let_unit_value)]
     unsafe {
         // Try to register class...
 
         #[cfg(before_api = "4.2")]
-        #[allow(clippy::let_unit_value)]
-        // notifies us if Godot API ever adds a return type.
         let _: () = interface_fn!(classdb_register_extension_class)(
             sys::get_library(),
             class_name.string_sys(),
             parent_class_name.string_sys(),
             ptr::addr_of!(info.godot_params),
         );
 
-        #[cfg(since_api = "4.2")]
-        #[allow(clippy::let_unit_value)]
-        // notifies us if Godot API ever adds a return type.
+        #[cfg(all(since_api = "4.2", before_api = "4.3"))]
         let _: () = interface_fn!(classdb_register_extension_class2)(
             sys::get_library(),
             class_name.string_sys(),
             parent_class_name.string_sys(),
             ptr::addr_of!(info.godot_params),
         );
 
+        #[cfg(since_api = "4.3")]
+        let _: () = interface_fn!(classdb_register_extension_class3)(
+            sys::get_library(),
+            class_name.string_sys(),
+            parent_class_name.string_sys(),
+            ptr::addr_of!(info.godot_params),
+        );
+
         // ...then see if it worked.
         // This is necessary because the above registration does not report errors (apart from console output).
         let tag = interface_fn!(classdb_get_class_tag)(class_name.string_sys());
@@ -602,8 +613,8 @@ fn default_registration_info(class_name: ClassName) -> ClassRegistrationInfo {
 #[cfg(before_api = "4.2")]
 fn default_creation_info() -> sys::GDExtensionClassCreationInfo {
     sys::GDExtensionClassCreationInfo {
-        is_abstract: false as u8,
         is_virtual: false as u8,
+        is_abstract: false as u8,
         set_func: None,
         get_func: None,
         get_property_list_func: None,
@@ -622,11 +633,12 @@ fn default_creation_info() -> sys::GDExtensionClassCreationInfo {
     }
 }
 
-#[cfg(since_api = "4.2")]
+#[cfg(all(since_api = "4.2", before_api = "4.3"))]
 fn default_creation_info() -> sys::GDExtensionClassCreationInfo2 {
     sys::GDExtensionClassCreationInfo2 {
-        is_abstract: false as u8,
         is_virtual: false as u8,
+        is_abstract: false as u8,
+        is_exposed: true as sys::GDExtensionBool,
         set_func: None,
         get_func: None,
         get_property_list_func: None,
@@ -646,6 +658,34 @@ fn default_creation_info() -> sys::GDExtensionClassCreationInfo2 {
         call_virtual_with_data_func: None,
         get_rid_func: None,
         class_userdata: ptr::null_mut(),
+    }
+}
+
+#[cfg(since_api = "4.3")]
+fn default_creation_info() -> sys::GDExtensionClassCreationInfo3 {
+    sys::GDExtensionClassCreationInfo3 {
+        is_virtual: false as u8,
+        is_abstract: false as u8,
         is_exposed: true as sys::GDExtensionBool,
+        is_runtime: true as sys::GDExtensionBool,
+        set_func: None,
+        get_func: None,
+        get_property_list_func: None,
+        free_property_list_func: None,
+        property_can_revert_func: None,
+        property_get_revert_func: None,
+        validate_property_func: None,
+        notification_func: None,
+        to_string_func: None,
+        reference_func: None,
+        unreference_func: None,
+        create_instance_func: None,
+        free_instance_func: None,
+        recreate_instance_func: None,
+        get_virtual_func: None,
+        get_virtual_call_data_func: None,
+        call_virtual_with_data_func: None,
+        get_rid_func: None,
+        class_userdata: ptr::null_mut(),
     }
 }

godot-ffi/src/binding/multi_threaded.rs

@@ -73,7 +73,10 @@ impl BindingStorage {
 }
 
 pub struct GdextConfig {
+    /// True if only `#[class(tool)]` classes are active in editor; false if all classes are.
     pub tool_only_in_editor: bool,
+
+    /// Whether the extension is loaded in an editor.
     is_editor: OnceLock<bool>,
 }
 

godot-macros/src/class/derive_godot_class.rs

@@ -104,6 +104,8 @@ pub fn derive_godot_class(decl: Declaration) -> ParseResult<TokenStream> {
         quote! { None }
     };
 
+    let is_tool = struct_cfg.is_tool;
+
     Ok(quote! {
         impl ::godot::obj::GodotClass for #class_name {
             type Base = #base_class;
@@ -136,6 +138,7 @@ pub fn derive_godot_class(decl: Declaration) -> ParseResult<TokenStream> {
                 },
                 free_fn: #prv::callbacks::free::<#class_name>,
                 default_get_virtual_fn: #default_get_virtual_fn,
+                is_tool: #is_tool,
                 is_editor_plugin: #is_editor_plugin,
                 is_hidden: #is_hidden,
                 is_instantiable: #is_instantiable,

godot-macros/src/class/godot_api.rs

@@ -729,6 +729,8 @@ fn transform_trait_impl(original_impl: venial::Impl) -> ParseResult<TokenStream>
                     impl ::godot::obj::cap::GodotNotification for #class_name {
                         fn __godot_notification(&mut self, what: i32) {
                             use ::godot::obj::UserClass as _;
+
+                            #[cfg(before_api = "4.3")]
                             if ::godot::private::is_class_inactive(Self::__config().is_tool) {
                                 return;
                             }
@@ -751,6 +753,8 @@ fn transform_trait_impl(original_impl: venial::Impl) -> ParseResult<TokenStream>
                     impl ::godot::obj::cap::GodotGet for #class_name {
                         fn __godot_get_property(&self, property: ::godot::builtin::StringName) -> Option<::godot::builtin::Variant> {
                             use ::godot::obj::UserClass as _;
+
+                            #[cfg(before_api = "4.3")]
                             if ::godot::private::is_class_inactive(Self::__config().is_tool) {
                                 return None;
                             }
@@ -772,6 +776,8 @@ fn transform_trait_impl(original_impl: venial::Impl) -> ParseResult<TokenStream>
                     impl ::godot::obj::cap::GodotSet for #class_name {
                         fn __godot_set_property(&mut self, property: ::godot::builtin::StringName, value: ::godot::builtin::Variant) -> bool {
                             use ::godot::obj::UserClass as _;
+
+                            #[cfg(before_api = "4.3")]
                             if ::godot::private::is_class_inactive(Self::__config().is_tool) {
                                 return false;
                             }

godot-macros/src/util/mod.rs

@@ -261,10 +261,16 @@ pub(crate) fn extract_cfg_attrs(
     })
 }
 
+#[cfg(before_api = "4.3")]
 pub fn make_virtual_tool_check() -> TokenStream {
     quote! {
         if ::godot::private::is_class_inactive(Self::__config().is_tool) {
             return None;
         }
     }
 }
+
+#[cfg(since_api = "4.3")]
+pub fn make_virtual_tool_check() -> TokenStream {
+    TokenStream::new()
+}