feat: Remove requirement for 'bindingToken' .

This is a giant refactor that completely removes the need for 'bindingTokens'. This should, eventually, allow me to get ride of `.cast` except to be used as an actual dynamic cast instead of a necessity over Dart `is` / `as`.

This still needs to be tested with a more complex project to see if it actually works.

example/2d_tutorial/.gitignore

@@ -7,3 +7,4 @@
 *.dylib
 *.pdb
 *.exp
+*.so

example/2d_tutorial/fonts/Xolonium-Regular.ttf.import

@@ -15,13 +15,15 @@ dest_files=["res://.godot/imported/Xolonium-Regular.ttf-bc2981e3069cff4c34dd7c8e
 Rendering=null
 antialiasing=1
 generate_mipmaps=false
+disable_embedded_bitmaps=true
 multichannel_signed_distance_field=false
 msdf_pixel_range=8
 msdf_size=48
 allow_system_fallback=true
 force_autohinter=false
 hinting=1
 subpixel_positioning=1
+keep_rounding_remainders=true
 oversampling=0.0
 Fallbacks=null
 fallbacks=[]

example/2d_tutorial/godot_dart.gdextension.uid

@@ -0,0 +1 @@
+uid://b6chiggk1agbi

example/2d_tutorial/main.tscn

@@ -1,6 +1,6 @@
 [gd_scene load_steps=9 format=4 uid="uid://tnm416ggiork"]
 
-[ext_resource type="Script" path="res://src/lib/game_logic.dart" id="1_724d8"]
+[ext_resource type="Script" uid="uid://wy5n7q67gfpi" path="res://src/lib/game_logic.dart" id="1_724d8"]
 [ext_resource type="PackedScene" uid="uid://j6e8fjrrm1xp" path="res://mob.tscn" id="2_7ma3k"]
 [ext_resource type="PackedScene" uid="uid://ylcs4f06tfbg" path="res://player.tscn" id="2_eccq4"]
 [ext_resource type="PackedScene" uid="uid://6a3aidlclhn4" path="res://hud.tscn" id="4_abxjl"]

example/2d_tutorial/project.godot

@@ -25,21 +25,21 @@ window/stretch/mode="canvas_items"
 
 move_right={
 "deadzone": 0.5,
-"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-3,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":0,"physical_keycode":4194321,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
+"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-1,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":0,"physical_keycode":4194321,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
 ]
 }
 move_left={
 "deadzone": 0.5,
-"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-3,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":0,"physical_keycode":4194319,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
+"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-1,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":0,"physical_keycode":4194319,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
 ]
 }
 move_up={
 "deadzone": 0.5,
-"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-3,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":0,"physical_keycode":4194320,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
+"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-1,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":0,"physical_keycode":4194320,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
 ]
 }
 move_down={
 "deadzone": 0.5,
-"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-3,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":0,"physical_keycode":4194322,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
+"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-1,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":0,"physical_keycode":4194322,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
 ]
 }

example/2d_tutorial/src/godot_dart_scripts.g.dart.uid

@@ -0,0 +1 @@
+uid://ccw2wbfog3u58

example/2d_tutorial/src/lib/game_logic.dart.uid

@@ -0,0 +1 @@
+uid://wy5n7q67gfpi

example/2d_tutorial/src/lib/game_logic.g.dart.uid

@@ -0,0 +1 @@
+uid://bxs73svhcgluv

example/2d_tutorial/src/lib/hud.dart.uid

@@ -0,0 +1 @@
+uid://cj0mstcs30fnk

example/2d_tutorial/src/lib/hud.g.dart.uid

@@ -0,0 +1 @@
+uid://8n72sq862ktq

example/2d_tutorial/src/lib/mob.dart.uid

@@ -0,0 +1 @@
+uid://cjjhbkgdf1t1e

example/2d_tutorial/src/lib/mob.g.dart.uid

@@ -0,0 +1 @@
+uid://dh20pv8eus6ui

example/2d_tutorial/src/lib/player.dart

@@ -62,7 +62,7 @@ class Player extends Area2D {
         animatedSprite?.setFlipV(velocity.y > 0);
       }
     } else {
-      getNodeT<AnimatedSprite2D>()?.stop();
+      animatedSprite?.stop();
     }
 
     var position = getPosition();

example/2d_tutorial/src/lib/player.dart.uid

@@ -0,0 +1 @@
+uid://doy5q8n0id6u6

example/2d_tutorial/src/lib/player.g.dart.uid

@@ -0,0 +1 @@
+uid://bm6hxkpovixtq

example/2d_tutorial/src/main.dart.uid

@@ -0,0 +1 @@
+uid://d0jqb13n3xw3w

src/cpp/dart_bindings.cpp

@@ -64,13 +64,19 @@ bool GodotDartBindings::initialize(const char *script_path, const char *package_
     Dart_SetMessageNotifyCallback(dart_message_notify_callback);
 
     Dart_Handle godot_dart_package_name = Dart_NewStringFromCString("package:godot_dart/godot_dart.dart");
-    Dart_Handle godot_dart_library = Dart_LookupLibrary(godot_dart_package_name);
-    if (Dart_IsError(godot_dart_library)) {
-      GD_PRINT_ERROR("GodotDart: Initialization Error (Could not find the `godot_dart` "
+    DART_CHECK_RET(godot_dart_library, Dart_LookupLibrary(godot_dart_package_name), false,
+                   "GodotDart: Initialization Error (Could not find the `godot_dart` "
+                   "package)");
+    _godot_dart_library = Dart_NewPersistentHandle(godot_dart_library);
+
+    // Find the Engine classes library. This is needed to lookup engine types
+    {
+      Dart_Handle engine_classes_package_name =
+          Dart_NewStringFromCString("package:godot_dart/src/gen/engine_classes.dart");
+      DART_CHECK_RET(engine_classes_library, Dart_LookupLibrary(engine_classes_package_name), false,
+                     "GodotDart: Initialization Error (Could not find the `engine_classes.dart` "
                      "package)");
-      return false;
-    } else {
-      _godot_dart_library = Dart_NewPersistentHandle(godot_dart_library);
+      _engine_classes_library = Dart_NewPersistentHandle(engine_classes_library);
     }
 
     // Find the DartBindings "library" (just the file) and set us as the native callback handler
@@ -83,11 +89,10 @@ bool GodotDartBindings::initialize(const char *script_path, const char *package_
       Dart_SetNativeResolver(library, native_resolver, nullptr);
     }
 
-    // Find the DartBindings "library" (just the file) and set us as the native callback handler
+    // Find the CoreTypes "library" (just the file) and set us as the native callback handler
     {
-      Dart_Handle native_bindings_library_name =
-          Dart_NewStringFromCString("package:godot_dart/src/core/core_types.dart");
-      DART_CHECK_RET(library, Dart_LookupLibrary(native_bindings_library_name), false, "Error finding core_types.dart");
+      Dart_Handle core_bindings_library_name = Dart_NewStringFromCString("package:godot_dart/src/core/core_types.dart");
+      DART_CHECK_RET(library, Dart_LookupLibrary(core_bindings_library_name), false, "Error finding core_types.dart");
       Dart_SetNativeResolver(library, native_resolver, nullptr);
     }
 
@@ -151,7 +156,7 @@ bool GodotDartBindings::initialize(const char *script_path, const char *package_
     {
       GDEWrapper *wrapper = GDEWrapper::instance();
       Dart_Handle args[] = {
-          Dart_NewInteger((int64_t)wrapper->get_library_ptr()),
+          Dart_NewInteger((int64_t)this),
           Dart_NewInteger(((int64_t)&DartGodotInstanceBinding::engine_binding_callbacks)),
       };
       DART_CHECK_RET(result, Dart_Invoke(godot_dart_library, Dart_NewStringFromCString("_registerGodot"), 2, args),
@@ -389,6 +394,25 @@ void GodotDartBindings::bind_method(const TypeInfo &bind_type, const char *metho
   delete[] arg_meta_info;
 }
 
+Dart_Handle GodotDartBindings::find_dart_type(Dart_Handle type_name) {
+  DartBlockScope scope;
+
+  uint8_t* c_type_name = nullptr;
+  intptr_t length = 0;
+  Dart_StringToUTF8(type_name, &c_type_name, &length);
+  if (0 == strncmp(reinterpret_cast<const char*>(c_type_name), "Object", length)) {
+    type_name = Dart_NewStringFromCString("GodotObject");
+  }
+
+  DART_CHECK_RET(engine_classes_library, Dart_HandleFromPersistent(_engine_classes_library), Dart_Null(),
+    "Error getting class class library.")
+
+  DART_CHECK_RET(type, Dart_GetNonNullableType(engine_classes_library, type_name, 0, nullptr), Dart_Null(),
+    "Could not find type in the engine_classes_library.");
+
+  return type;
+}
+
 void GodotDartBindings::add_property(const TypeInfo &bind_type, Dart_Handle dart_prop_info) {
 
   GDExtensionPropertyInfo prop_info = {};
@@ -791,25 +815,9 @@ void gd_object_to_dart_object(Dart_NativeArguments args) {
   }
 
   GDEWrapper *gde = GDEWrapper::instance();
-
-  // Default for non-engine classes
-  void *token = gde->get_library_ptr();
-
-  Dart_Handle bindings_token = Dart_GetNativeArgument(args, 2);
-  if (!Dart_IsNull(bindings_token)) {
-    address = Dart_GetField(bindings_token, Dart_NewStringFromCString("address"));
-    if (Dart_IsError(address)) {
-      GD_PRINT_ERROR(Dart_GetError(address));
-      Dart_ThrowException(Dart_NewStringFromCString(Dart_GetError(address)));
-      return;
-    }
-    uint64_t token_int = 0;
-    Dart_IntegerToUint64(address, &token_int);
-    token = (void *)token_int;    
-  }
 
   DartGodotInstanceBinding *binding = (DartGodotInstanceBinding *)gde_object_get_instance_binding(
-      reinterpret_cast<GDExtensionObjectPtr>(object_ptr), token, &DartGodotInstanceBinding::engine_binding_callbacks);
+      reinterpret_cast<GDExtensionObjectPtr>(object_ptr), bindings, &DartGodotInstanceBinding::engine_binding_callbacks);
   if (binding == nullptr) {
     Dart_SetReturnValue(args, Dart_Null());
   } else {
@@ -897,27 +905,15 @@ void type_info_from_dart(TypeInfo *type_info, Dart_Handle dart_type_info) {
 
   Dart_Handle class_name = Dart_GetField(dart_type_info, Dart_NewStringFromCString("className"));
   Dart_Handle parent_type = Dart_GetField(dart_type_info, Dart_NewStringFromCString("parentType"));
-  Dart_Handle variant_type = Dart_GetField(dart_type_info, Dart_NewStringFromCString("variantType"));
-  Dart_Handle binding_token = Dart_GetField(dart_type_info, Dart_NewStringFromCString("bindingToken"));
+  Dart_Handle variant_type = Dart_GetField(dart_type_info, Dart_NewStringFromCString("variantType"));  
 
   type_info->type_name = get_object_address(class_name);
   type_info->parent_type = parent_type;
 
   int64_t temp;
   Dart_IntegerToInt64(variant_type, &temp);
   type_info->variant_type = static_cast<GDExtensionVariantType>(temp);
-  if (Dart_IsNull(binding_token)) {
-    type_info->binding_token = nullptr;
-    type_info->binding_callbacks = nullptr;
-  } else {
-    Dart_Handle dart_address = Dart_GetField(binding_token, Dart_NewStringFromCString("address"));
-
-    uint64_t address = 0;
-    Dart_IntegerToUint64(dart_address, &address);
-
-    type_info->binding_token = (void *)address;
-    type_info->binding_callbacks = &DartGodotInstanceBinding::engine_binding_callbacks;
-  }
+  type_info->binding_callbacks = &DartGodotInstanceBinding::engine_binding_callbacks;
 
   Dart_ExitScope();
 }
@@ -928,6 +924,7 @@ extern "C" {
 
 GDE_EXPORT void tie_dart_to_native(Dart_Handle dart_object, GDExtensionObjectPtr godot_object, bool is_refcounted,
                                    bool is_godot_defined) {
+  GodotDartBindings *bindings = GodotDartBindings::instance();
   DartBlockScope scope;
 
   Dart_Handle d_class_type_info = Dart_GetField(dart_object, Dart_NewStringFromCString("typeInfo"));
@@ -942,7 +939,7 @@ GDE_EXPORT void tie_dart_to_native(Dart_Handle dart_object, GDExtensionObjectPtr
 
   const GDExtensionInstanceBindingCallbacks *callbacks = &DartGodotInstanceBinding::engine_binding_callbacks;
   DartGodotInstanceBinding *binding = (DartGodotInstanceBinding *)gde_object_get_instance_binding(
-      godot_object, class_type_info.binding_token, callbacks);
+      godot_object, bindings, callbacks);
   if (!binding->is_initialized()) {
     binding->initialize(dart_object, is_refcounted);
   }
@@ -1033,5 +1030,4 @@ GDE_EXPORT void *safe_new_persistent_handle(Dart_Handle handle) {
 
   return (void *)result;
 }
-
 }

src/cpp/dart_bindings.h

@@ -44,6 +44,7 @@ class GodotDartBindings {
 
   void bind_method(const TypeInfo &bind_type, const char *method_name, const TypeInfo &ret_type_info,
                    Dart_Handle args_list, MethodFlags method_flags);
+  Dart_Handle find_dart_type(Dart_Handle type_name);
   void add_property(const TypeInfo &bind_type, Dart_Handle dart_prop_info);
   void execute_on_dart_thread(std::function<void()> work);
   Dart_Handle new_dart_void_pointer(void *ptr);
@@ -82,6 +83,7 @@ class GodotDartBindings {
   std::set<DartGodotInstanceBinding *> _pending_ref_changes;
 
   Dart_PersistentHandle _godot_dart_library;
+  Dart_PersistentHandle _engine_classes_library;
   Dart_PersistentHandle _native_library;
 
   // Some things we need often

src/cpp/dart_instance_binding.cpp

@@ -1,11 +1,13 @@
 #include "dart_instance_binding.h"
 
 #include <godot_cpp/classes/object.hpp>
+#include <godot_cpp/godot.hpp>
 
-#include "dart_helpers.h"
 #include "dart_bindings.h"
+#include "dart_helpers.h"
 #include "gde_c_interface.h"
 #include "ref_counted_wrapper.h"
+#include "godot_string_wrappers.h"
 
 void gde_weak_finalizer(void *isolate_callback_data, void *peer) {
   if (peer == nullptr) {
@@ -22,7 +24,7 @@ void gde_weak_finalizer(void *isolate_callback_data, void *peer) {
   }
 }
 
-std::map<intptr_t, DartGodotInstanceBinding*> DartGodotInstanceBinding::s_instanceMap;
+std::map<intptr_t, DartGodotInstanceBinding *> DartGodotInstanceBinding::s_instanceMap;
 
 DartGodotInstanceBinding::~DartGodotInstanceBinding() {
   GodotDartBindings *bindings = GodotDartBindings::instance();
@@ -38,12 +40,10 @@ DartGodotInstanceBinding::~DartGodotInstanceBinding() {
     // Don't attempt to execute on the Dart isolate if this is the case
     // (it might be already doing things)
     Dart_IsolateGroup current_isolate_group = Dart_CurrentIsolateGroup();
-    if(current_isolate_group) {
+    if (current_isolate_group) {
       delete_dart_handle();
     } else {
-      GodotDartBindings::instance()->execute_on_dart_thread([&]{
-        delete_dart_handle();
-      });
+      GodotDartBindings::instance()->execute_on_dart_thread([&] { delete_dart_handle(); });
     }
     bindings->remove_pending_ref_change(this);
   }
@@ -136,7 +136,7 @@ void DartGodotInstanceBinding::create_dart_object() {
   }
 
   bindings->execute_on_dart_thread([&] {
-    Dart_PersistentHandle persistent_type = reinterpret_cast<Dart_PersistentHandle>(_token);
+    Dart_PersistentHandle persistent_type = reinterpret_cast<Dart_PersistentHandle>(_dart_type);
     Dart_Handle dart_type = Dart_HandleFromPersistent(persistent_type);
 
     Dart_Handle dart_pointer = bindings->new_dart_void_pointer(_godot_object);
@@ -152,7 +152,26 @@ void DartGodotInstanceBinding::create_dart_object() {
 /* Binding callbacks used for Engine types implemented in Godot and wrapped in Dart */
 
 static void *__engine_binding_create_callback(void *p_token, void *p_instance) {
-  DartGodotInstanceBinding *binding = new DartGodotInstanceBinding(p_token, p_instance);
+  GodotDartBindings *bindings = GodotDartBindings::instance();  
+  godot::StringName class_name;
+
+  DartGodotInstanceBinding *binding = nullptr;
+  if (godot::internal::gdextension_interface_object_get_class_name(
+          p_instance, p_token, reinterpret_cast<GDExtensionStringNamePtr>(class_name._native_ptr()))) {
+    bindings->execute_on_dart_thread([&] {
+      Dart_EnterScope();
+
+      Dart_Handle type_name = to_dart_string(class_name);
+      DART_CHECK(type, bindings->find_dart_type(type_name), "Error finding Dart type");
+      if (!Dart_IsNull(type)) {
+        Dart_PersistentHandle persistent_type = Dart_NewPersistentHandle(type);
+        binding = new DartGodotInstanceBinding(persistent_type, p_instance);
+      }
+
+      Dart_ExitScope();
+    });
+  }
+
   return binding;
 }
 
@@ -164,10 +183,10 @@ static void __engine_binding_free_callback(void *p_token, void *p_instance, void
     delete binding;
     return;
   }
-  
+
   if (binding->is_weak() || bindings->_is_stopping) {
-    // If the binding is weak or we're shutting down, there's a possibility Dart is asking us 
-    // to kill this in a way that does not allow us to call back into any other Dart code other 
+    // If the binding is weak or we're shutting down, there's a possibility Dart is asking us
+    // to kill this in a way that does not allow us to call back into any other Dart code other
     // than deleting the reference. So just do that and be done with it.
     delete binding;
     return;
@@ -222,9 +241,7 @@ static GDExtensionBool __engine_binding_reference_callback(void *p_token, void *
     // Refcount incremented, change our reference to strong to prevent Dart from finalizing
     if (refcount > 1 && engine_binding->is_weak()) {
       if (!is_finalizer) {
-        bindings->execute_on_dart_thread([&] { 
-          engine_binding->convert_to_strong();
-        });
+        bindings->execute_on_dart_thread([&] { engine_binding->convert_to_strong(); });
       } else {
         bindings->add_pending_ref_change(engine_binding);
       }
@@ -234,13 +251,11 @@ static GDExtensionBool __engine_binding_reference_callback(void *p_token, void *
   } else {
     if (refcount == 1 && !engine_binding->is_weak()) {
       if (!is_finalizer) {
-        bindings->execute_on_dart_thread([&] {
-          engine_binding->convert_to_weak();
-        });
+        bindings->execute_on_dart_thread([&] { engine_binding->convert_to_weak(); });
       } else {
         bindings->add_pending_ref_change(engine_binding);
       }
-      
+
       is_dieing = false;
     }
   }

src/cpp/dart_instance_binding.h

@@ -9,8 +9,8 @@
 // persitent handles, encapsulate that into a custom GC handle
 class DartGodotInstanceBinding {
 public:
-  DartGodotInstanceBinding(void *token, GDExtensionObjectPtr godot_object)
-      : _is_refcounted(false), _is_weak(false), _persistent_handle(nullptr), _godot_object(godot_object), _token(token) {
+  DartGodotInstanceBinding(Dart_PersistentHandle dart_type, GDExtensionObjectPtr godot_object)
+      : _is_refcounted(false), _is_weak(false), _persistent_handle(nullptr), _godot_object(godot_object), _dart_type(dart_type) {
   }
 
   ~DartGodotInstanceBinding();
@@ -46,7 +46,7 @@ class DartGodotInstanceBinding {
   bool _is_weak;
   void *_persistent_handle;
   GDExtensionObjectPtr _godot_object;
-  void *_token;
+  Dart_PersistentHandle _dart_type;  
 };
 
 void gde_weak_finalizer(void *isolate_callback_data, void *peer);