Avoid creating objects that Godot is going to use placement new to in…

…itialize
godotengine · Feb 26, 2024 · 50f7123 · 50f7123
1 parent 36847f6
commit 50f7123
Show file tree

Hide file tree

Showing 3 changed files with 29 additions and 44 deletions.
diff --git a/binding_generator.py b/binding_generator.py
@@ -454,6 +454,8 @@ def generate_builtin_class_header(builtin_api, size, used_classes, fully_used_cl
     result.append("")
     result.append("\tstatic struct _MethodBindings {")
 
+    result.append("\t\tGDExtensionTypeFromVariantConstructorFunc from_variant_constructor;")
+
     if "constructors" in builtin_api:
         for constructor in builtin_api["constructors"]:
             result.append(f'\t\tGDExtensionPtrConstructor constructor_{constructor["index"]};')
@@ -494,6 +496,9 @@ def generate_builtin_class_header(builtin_api, size, used_classes, fully_used_cl
     result.append("\tstatic void init_bindings();")
     result.append("\tstatic void _init_bindings_constructors_destructor();")
 
+    result.append("")
+    result.append(f"\t{class_name}(const Variant *p_variant);")
+
     result.append("")
     result.append("public:")
 
@@ -818,6 +823,10 @@ def generate_builtin_class_source(builtin_api, size, used_classes, fully_used_cl
 
     result.append(f"void {class_name}::_init_bindings_constructors_destructor() {{")
 
+    result.append(
+        f"\t_method_bindings.from_variant_constructor = internal::gdextension_interface_get_variant_to_type_constructor({enum_type_name});"
+    )
+
     if "constructors" in builtin_api:
         for constructor in builtin_api["constructors"]:
             result.append(
@@ -899,6 +908,11 @@ def generate_builtin_class_source(builtin_api, size, used_classes, fully_used_cl
 
     copy_constructor_index = -1
 
+    result.append(f"{class_name}::{class_name}(const Variant *p_variant) {{")
+    result.append("\t_method_bindings.from_variant_constructor(&opaque, p_variant->_native_ptr());")
+    result.append("}")
+    result.append("")
+
     if "constructors" in builtin_api:
         for constructor in builtin_api["constructors"]:
             method_signature = f"{class_name}::{class_name}("

diff --git a/include/godot_cpp/variant/variant.hpp b/include/godot_cpp/variant/variant.hpp
@@ -47,8 +47,6 @@ class ObjectID;
 class Variant {
 	uint8_t opaque[GODOT_CPP_VARIANT_SIZE]{ 0 };
 
-	_FORCE_INLINE_ GDExtensionVariantPtr _native_ptr() const { return const_cast<uint8_t(*)[GODOT_CPP_VARIANT_SIZE]>(&opaque); }
-
 	friend class GDExtensionBinding;
 	friend class MethodBind;
 
@@ -145,6 +143,7 @@ class Variant {
 	static GDExtensionTypeFromVariantConstructorFunc to_type_constructor[VARIANT_MAX];
 
 public:
+	_FORCE_INLINE_ GDExtensionVariantPtr _native_ptr() const { return const_cast<uint8_t(*)[GODOT_CPP_VARIANT_SIZE]>(&opaque); }
 	Variant();
 	Variant(std::nullptr_t n) :
 			Variant() {}

diff --git a/src/variant/variant.cpp b/src/variant/variant.cpp
@@ -303,9 +303,7 @@ Variant::operator float() const {
 }
 
 Variant::operator String() const {
-	String result;
-	to_type_constructor[STRING](result._native_ptr(), _native_ptr());
-	return result;
+	return String(this);
 }
 
 Variant::operator Vector2() const {
@@ -447,81 +445,55 @@ Variant::operator ObjectID() const {
 }
 
 Variant::operator Callable() const {
-	Callable result;
-	to_type_constructor[CALLABLE](result._native_ptr(), _native_ptr());
-	return result;
+	return Callable(this);
 }
 
 Variant::operator Signal() const {
-	Signal result;
-	to_type_constructor[SIGNAL](result._native_ptr(), _native_ptr());
-	return result;
+	return Signal(this);
 }
 
 Variant::operator Dictionary() const {
-	Dictionary result;
-	to_type_constructor[DICTIONARY](result._native_ptr(), _native_ptr());
-	return result;
+	return Dictionary(this);
 }
 
 Variant::operator Array() const {
-	Array result;
-	to_type_constructor[ARRAY](result._native_ptr(), _native_ptr());
-	return result;
+	return Array(this);
 }
 
 Variant::operator PackedByteArray() const {
-	PackedByteArray result;
-	to_type_constructor[PACKED_BYTE_ARRAY](result._native_ptr(), _native_ptr());
-	return result;
+	return PackedByteArray(this);
 }
 
 Variant::operator PackedInt32Array() const {
-	PackedInt32Array result;
-	to_type_constructor[PACKED_INT32_ARRAY](result._native_ptr(), _native_ptr());
-	return result;
+	return PackedInt32Array(this);
 }
 
 Variant::operator PackedInt64Array() const {
-	PackedInt64Array result;
-	to_type_constructor[PACKED_INT64_ARRAY](result._native_ptr(), _native_ptr());
-	return result;
+	return PackedInt64Array(this);
 }
 
 Variant::operator PackedFloat32Array() const {
-	PackedFloat32Array result;
-	to_type_constructor[PACKED_FLOAT32_ARRAY](result._native_ptr(), _native_ptr());
-	return result;
+	return PackedFloat32Array(this);
 }
 
 Variant::operator PackedFloat64Array() const {
-	PackedFloat64Array result;
-	to_type_constructor[PACKED_FLOAT64_ARRAY](result._native_ptr(), _native_ptr());
-	return result;
+	return PackedFloat64Array(this);
 }
 
 Variant::operator PackedStringArray() const {
-	PackedStringArray result;
-	to_type_constructor[PACKED_STRING_ARRAY](result._native_ptr(), _native_ptr());
-	return result;
+	return PackedStringArray(this);
 }
 
 Variant::operator PackedVector2Array() const {
-	PackedVector2Array result;
-	to_type_constructor[PACKED_VECTOR2_ARRAY](result._native_ptr(), _native_ptr());
-	return result;
+	return PackedVector2Array(this);
 }
 
 Variant::operator PackedVector3Array() const {
-	PackedVector3Array result;
-	to_type_constructor[PACKED_VECTOR3_ARRAY](result._native_ptr(), _native_ptr());
-	return result;
+	return PackedVector3Array(this);
 }
 
 Variant::operator PackedColorArray() const {
-	PackedColorArray result;
-	to_type_constructor[PACKED_COLOR_ARRAY](result._native_ptr(), _native_ptr());
-	return result;
+	return PackedColorArray(this);
 }
 
 Variant &Variant::operator=(const Variant &other) {