Add a type conversion method to Variant Utility and expose to scripting

core/variant/variant_utility.cpp

@@ -741,6 +741,90 @@ struct VariantUtilityFunctions {
 		return obj.get_type();
 	}
 
+	static inline Variant type_convert(const Variant &p_variant, const Variant::Type p_type) {
+		switch (p_type) {
+			case Variant::Type::NIL:
+				return Variant();
+			case Variant::Type::BOOL:
+				return p_variant.operator bool();
+			case Variant::Type::INT:
+				return p_variant.operator int64_t();
+			case Variant::Type::FLOAT:
+				return p_variant.operator double();
+			case Variant::Type::STRING:
+				return p_variant.operator String();
+			case Variant::Type::VECTOR2:
+				return p_variant.operator Vector2();
+			case Variant::Type::VECTOR2I:
+				return p_variant.operator Vector2i();
+			case Variant::Type::RECT2:
+				return p_variant.operator Rect2();
+			case Variant::Type::RECT2I:
+				return p_variant.operator Rect2i();
+			case Variant::Type::VECTOR3:
+				return p_variant.operator Vector3();
+			case Variant::Type::VECTOR3I:
+				return p_variant.operator Vector3i();
+			case Variant::Type::TRANSFORM2D:
+				return p_variant.operator Transform2D();
+			case Variant::Type::VECTOR4:
+				return p_variant.operator Vector4();
+			case Variant::Type::VECTOR4I:
+				return p_variant.operator Vector4i();
+			case Variant::Type::PLANE:
+				return p_variant.operator Plane();
+			case Variant::Type::QUATERNION:
+				return p_variant.operator Quaternion();
+			case Variant::Type::AABB:
+				return p_variant.operator ::AABB();
+			case Variant::Type::BASIS:
+				return p_variant.operator Basis();
+			case Variant::Type::TRANSFORM3D:
+				return p_variant.operator Transform3D();
+			case Variant::Type::PROJECTION:
+				return p_variant.operator Projection();
+			case Variant::Type::COLOR:
+				return p_variant.operator Color();
+			case Variant::Type::STRING_NAME:
+				return p_variant.operator StringName();
+			case Variant::Type::NODE_PATH:
+				return p_variant.operator NodePath();
+			case Variant::Type::RID:
+				return p_variant.operator ::RID();
+			case Variant::Type::OBJECT:
+				return p_variant.operator Object *();
+			case Variant::Type::CALLABLE:
+				return p_variant.operator Callable();
+			case Variant::Type::SIGNAL:
+				return p_variant.operator Signal();
+			case Variant::Type::DICTIONARY:
+				return p_variant.operator Dictionary();
+			case Variant::Type::ARRAY:
+				return p_variant.operator Array();
+			case Variant::Type::PACKED_BYTE_ARRAY:
+				return p_variant.operator PackedByteArray();
+			case Variant::Type::PACKED_INT32_ARRAY:
+				return p_variant.operator PackedInt32Array();
+			case Variant::Type::PACKED_INT64_ARRAY:
+				return p_variant.operator PackedInt64Array();
+			case Variant::Type::PACKED_FLOAT32_ARRAY:
+				return p_variant.operator PackedFloat32Array();
+			case Variant::Type::PACKED_FLOAT64_ARRAY:
+				return p_variant.operator PackedFloat64Array();
+			case Variant::Type::PACKED_STRING_ARRAY:
+				return p_variant.operator PackedStringArray();
+			case Variant::Type::PACKED_VECTOR2_ARRAY:
+				return p_variant.operator PackedVector2Array();
+			case Variant::Type::PACKED_VECTOR3_ARRAY:
+				return p_variant.operator PackedVector3Array();
+			case Variant::Type::PACKED_COLOR_ARRAY:
+				return p_variant.operator PackedColorArray();
+			default:
+				ERR_PRINT("Invalid type argument to type_convert(), use the TYPE_* constants. Returning the unconverted Variant.");
+				return p_variant;
+		}
+	}
+
 	static inline String str(const Variant **p_args, int p_arg_count, Callable::CallError &r_error) {
 		if (p_arg_count < 1) {
 			r_error.error = Callable::CallError::CALL_ERROR_TOO_FEW_ARGUMENTS;
@@ -1599,6 +1683,7 @@ void Variant::_register_variant_utility_functions() {
 
 	FUNCBINDVR(weakref, sarray("obj"), Variant::UTILITY_FUNC_TYPE_GENERAL);
 	FUNCBINDR(_typeof, sarray("variable"), Variant::UTILITY_FUNC_TYPE_GENERAL);
+	FUNCBINDR(type_convert, sarray("variant", "type"), Variant::UTILITY_FUNC_TYPE_GENERAL);
 	FUNCBINDVARARGS(str, sarray(), Variant::UTILITY_FUNC_TYPE_GENERAL);
 	FUNCBINDR(error_string, sarray("error"), Variant::UTILITY_FUNC_TYPE_GENERAL);
 	FUNCBINDVARARGV(print, sarray(), Variant::UTILITY_FUNC_TYPE_GENERAL);

doc/classes/@GlobalScope.xml

@@ -1321,6 +1321,23 @@
 				[/codeblock]
 			</description>
 		</method>
+		<method name="type_convert">
+			<return type="Variant" />
+			<param index="0" name="variant" type="Variant" />
+			<param index="1" name="type" type="int" />
+			<description>
+				Converts the given [param variant] to the given [param type], using the [enum Variant.Type] values. This method is generous with how it handles types, it can automatically convert between array types, convert numeric [String]s to [int], and converting most things to [String].
+				If the type conversion cannot be done, this method will return the default value for that type, for example converting [Rect2] to [Vector2] will always return [code]Vector2.ZERO[/code]. This method will never show error messages as long as [param type] is a valid Variant type.
+				The returned value is a [Variant], but the data inside and the [enum Variant.Type] will be the same as the requested type.
+				[codeblock]
+				type_convert("Hi!", TYPE_INT) # Returns 0
+				type_convert("123", TYPE_INT) # Returns 123
+				type_convert(123.4, TYPE_INT) # Returns 123
+				type_convert(5, TYPE_VECTOR2) # Returns (0, 0)
+				type_convert("Hi!", TYPE_NIL) # Returns null
+				[/codeblock]
+			</description>
+		</method>
 		<method name="typeof">
 			<return type="int" />
 			<param index="0" name="variable" type="Variant" />

tests/core/variant/test_variant_utility.h

@@ -0,0 +1,119 @@
+/**************************************************************************/
+/*  test_variant_utility.h                                                */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* Permission is hereby granted, free of charge, to any person obtaining  */
+/* a copy of this software and associated documentation files (the        */
+/* "Software"), to deal in the Software without restriction, including    */
+/* without limitation the rights to use, copy, modify, merge, publish,    */
+/* distribute, sublicense, and/or sell copies of the Software, and to     */
+/* permit persons to whom the Software is furnished to do so, subject to  */
+/* the following conditions:                                              */
+/*                                                                        */
+/* The above copyright notice and this permission notice shall be         */
+/* included in all copies or substantial portions of the Software.        */
+/*                                                                        */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
+/**************************************************************************/
+
+#ifndef TEST_VARIANT_UTILITY_H
+#define TEST_VARIANT_UTILITY_H
+
+// There is no variant_utility.h, so include the cpp.
+#include "core/variant/variant_utility.cpp"
+
+#include "tests/test_macros.h"
+
+namespace TestVariantUtility {
+
+TEST_CASE("[VariantUtility] Type conversion") {
+	Variant converted;
+	converted = VariantUtilityFunctions::type_convert("Hi!", Variant::Type::NIL);
+	CHECK(converted.get_type() == Variant::Type::NIL);
+	CHECK(converted == Variant());
+
+	converted = VariantUtilityFunctions::type_convert("Hi!", Variant::Type::INT);
+	CHECK(converted.get_type() == Variant::Type::INT);
+	CHECK(converted == Variant(0));
+
+	converted = VariantUtilityFunctions::type_convert("123", Variant::Type::INT);
+	CHECK(converted.get_type() == Variant::Type::INT);
+	CHECK(converted == Variant(123));
+
+	converted = VariantUtilityFunctions::type_convert(123, Variant::Type::STRING);
+	CHECK(converted.get_type() == Variant::Type::STRING);
+	CHECK(converted == Variant("123"));
+
+	converted = VariantUtilityFunctions::type_convert(123.4, Variant::Type::INT);
+	CHECK(converted.get_type() == Variant::Type::INT);
+	CHECK(converted == Variant(123));
+
+	converted = VariantUtilityFunctions::type_convert(5, Variant::Type::VECTOR2);
+	CHECK(converted.get_type() == Variant::Type::VECTOR2);
+	CHECK(converted == Variant(Vector2(0, 0)));
+
+	converted = VariantUtilityFunctions::type_convert(Vector3(1, 2, 3), Variant::Type::VECTOR2);
+	CHECK(converted.get_type() == Variant::Type::VECTOR2);
+	CHECK(converted == Variant(Vector2(1, 2)));
+
+	converted = VariantUtilityFunctions::type_convert(Vector2(1, 2), Variant::Type::VECTOR4);
+	CHECK(converted.get_type() == Variant::Type::VECTOR4);
+	CHECK(converted == Variant(Vector4(1, 2, 0, 0)));
+
+	converted = VariantUtilityFunctions::type_convert(Vector4(1.2, 3.4, 5.6, 7.8), Variant::Type::VECTOR3I);
+	CHECK(converted.get_type() == Variant::Type::VECTOR3I);
+	CHECK(converted == Variant(Vector3i(1, 3, 5)));
+
+	{
+		Basis basis = Basis::from_scale(Vector3(1.2, 3.4, 5.6));
+		Transform3D transform = Transform3D(basis, Vector3());
+
+		converted = VariantUtilityFunctions::type_convert(transform, Variant::Type::BASIS);
+		CHECK(converted.get_type() == Variant::Type::BASIS);
+		CHECK(converted == basis);
+
+		converted = VariantUtilityFunctions::type_convert(basis, Variant::Type::TRANSFORM3D);
+		CHECK(converted.get_type() == Variant::Type::TRANSFORM3D);
+		CHECK(converted == transform);
+
+		converted = VariantUtilityFunctions::type_convert(basis, Variant::Type::STRING);
+		CHECK(converted.get_type() == Variant::Type::STRING);
+		CHECK(converted == Variant("[X: (1.2, 0, 0), Y: (0, 3.4, 0), Z: (0, 0, 5.6)]"));
+	}
+
+	{
+		Array arr;
+		arr.push_back(1.2);
+		arr.push_back(3.4);
+		arr.push_back(5.6);
+
+		PackedFloat64Array packed;
+		packed.push_back(1.2);
+		packed.push_back(3.4);
+		packed.push_back(5.6);
+
+		converted = VariantUtilityFunctions::type_convert(arr, Variant::Type::PACKED_FLOAT64_ARRAY);
+		CHECK(converted.get_type() == Variant::Type::PACKED_FLOAT64_ARRAY);
+		CHECK(converted == packed);
+
+		converted = VariantUtilityFunctions::type_convert(packed, Variant::Type::ARRAY);
+		CHECK(converted.get_type() == Variant::Type::ARRAY);
+		CHECK(converted == arr);
+	}
+}
+
+} // namespace TestVariantUtility
+
+#endif // TEST_VARIANT_UTILITY_H

tests/test_main.cpp

@@ -86,6 +86,7 @@
 #include "tests/core/variant/test_array.h"
 #include "tests/core/variant/test_dictionary.h"
 #include "tests/core/variant/test_variant.h"
+#include "tests/core/variant/test_variant_utility.h"
 #include "tests/scene/test_animation.h"
 #include "tests/scene/test_arraymesh.h"
 #include "tests/scene/test_audio_stream_wav.h"