Added a new CBoxContainer type which acts as both a VBoxContainer and HBoxContainer and allows changing between them using a property.

doc/classes/CBoxContainer.xml

@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<class name="CBoxContainer" inherits="BoxContainer" version="4.2">
+	<brief_description>
+		Horizontal or vertical box container.
+	</brief_description>
+	<description>
+		Horizontal or vertical box container depending on it's [member mode] setting. See [BoxContainer].
+	</description>
+	<tutorials>
+		<link title="GUI containers">$DOCS_URL/tutorials/ui/gui_containers.md</link>
+	</tutorials>
+	<methods>
+	</methods>
+	<members>
+		<member name="mode" type="int" setter="set_mode" getter="get_mode" enum="CBoxContainer.ContainerMode" default="0">
+			Sets whether this [CBoxContainer] will act as a [HBoxContainer] or a [VBoxContainer].
+		</member>
+	</members>
+	<constants>
+		<constant name="CONTAINER_MODE_HORIZONTAL" value="0" enum="ContainerMode">
+			This [CBoxContainer] will act as a [HBoxContainer].
+		</constant>
+		<constant name="CONTAINER_MODE_VERTICAL" value="1" enum="ContainerMode">
+			This [CBoxContainer] will act as a [VBoxContainer].
+		</constant>
+	</constants>
+	<theme_items>
+		<theme_item name="separation" data_type="constant" type="int" default="4">
+			The horizontal or vertical space between the [CBoxContainer]'s elements.
+		</theme_item>
+	</theme_items>
+</class>

editor/icons/icon_c_box_container.svg

@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   height="16"
+   viewBox="0 0 16 16"
+   width="16"
+   version="1.1"
+   id="svg1"
+   sodipodi:docname="icon_c_box_container.svg"
+   inkscape:version="1.3 (0e150ed6c4, 2023-07-21)"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg">
+  <defs
+     id="defs1" />
+  <sodipodi:namedview
+     id="namedview1"
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1.0"
+     inkscape:showpageshadow="2"
+     inkscape:pageopacity="0.0"
+     inkscape:pagecheckerboard="0"
+     inkscape:deskcolor="#d1d1d1"
+     inkscape:zoom="51.1875"
+     inkscape:cx="7.990232"
+     inkscape:cy="8"
+     inkscape:window-width="1920"
+     inkscape:window-height="1023"
+     inkscape:window-x="3840"
+     inkscape:window-y="0"
+     inkscape:window-maximized="1"
+     inkscape:current-layer="svg1" />
+  <path
+     id="path1"
+     d="M 3 1 C 1.8954011 1 1 1.8954311 1 3 L 1 13 C 1 14.104599 1.8954311 15 3 15 L 7.9003906 15 L 7.9003906 13 L 7 13 L 7 3 L 7.9003906 3 L 7.9003906 1 L 3 1 z M 3 3 L 5 3 L 5 13 L 3 13 L 3 3 z "
+     style="fill:#a5efac;fill-opacity:1" />
+  <path
+     id="path1-5"
+     d="M 8.2636719 1 L 8.2636719 3 L 13 3 L 13 5 L 8.2636719 5 L 8.2636719 7 L 13 7 L 13 9 L 8.2636719 9 L 8.2636719 11 L 13 11 L 13 13 L 8.2636719 13 L 8.2636719 15 L 13 15 C 14.104599 15 15 14.104599 15 13 L 15 3 C 15 1.8954011 14.104569 1 13 1 L 8.2636719 1 z "
+     style="fill:#a5efac;fill-opacity:1" />
+</svg>

scene/gui/box_container.cpp

@@ -32,6 +32,116 @@
 #include "label.h"
 #include "margin_container.h"
 
+Size2 BoxContainer::get_minimum_size() const {
+	/* Calculate MINIMUM SIZE */
+
+	Size2i minimum;
+	int sep = get_theme_constant("separation"); //,vertical?"VBoxContainer":"HBoxContainer");
+
+	bool first = true;
+
+	for (int i = 0; i < get_child_count(); i++) {
+		Control *c = Object::cast_to<Control>(get_child(i));
+		if (!c) {
+			continue;
+		}
+		if (c->is_set_as_toplevel()) {
+			continue;
+		}
+
+		if (!c->is_visible()) {
+			continue;
+		}
+
+		Size2i size = c->get_combined_minimum_size();
+
+		if (vertical) { /* VERTICAL */
+
+			if (size.width > minimum.width) {
+				minimum.width = size.width;
+			}
+
+			minimum.height += size.height + (first ? 0 : sep);
+
+		} else { /* HORIZONTAL */
+
+			if (size.height > minimum.height) {
+				minimum.height = size.height;
+			}
+
+			minimum.width += size.width + (first ? 0 : sep);
+		}
+
+		first = false;
+	}
+
+	return minimum;
+}
+
+void BoxContainer::set_alignment(AlignMode p_align) {
+	align = p_align;
+	_resort();
+}
+
+BoxContainer::AlignMode BoxContainer::get_alignment() const {
+	return align;
+}
+
+void BoxContainer::add_spacer(bool p_begin) {
+	Control *c = memnew(Control);
+	c->set_mouse_filter(MOUSE_FILTER_PASS); //allow spacer to pass mouse events
+	c->set_meta("is_box_container_spacer", true);
+
+	if (vertical) {
+		c->set_v_size_flags(SIZE_EXPAND_FILL);
+	} else {
+		c->set_h_size_flags(SIZE_EXPAND_FILL);
+	}
+
+	add_child(c);
+	if (p_begin) {
+		move_child(c, 0);
+	}
+}
+
+BoxContainer::BoxContainer(bool p_vertical) {
+	vertical = p_vertical;
+	align = ALIGN_BEGIN;
+	//set_ignore_mouse(true);
+	set_mouse_filter(MOUSE_FILTER_PASS);
+}
+
+bool BoxContainer::_get_vertical() const {
+	return vertical;
+}
+void BoxContainer::_set_vertical(bool p_vertical) {
+	if (vertical == p_vertical) {
+		return;
+	}
+
+	vertical = p_vertical;
+
+	int cc = get_child_count();
+
+	for (int i = 0; i < cc; ++i) {
+		Control *c = Object::cast_to<Control>(get_child(i));
+
+		if (c) {
+			if (c->has_meta("is_box_container_spacer")) {
+				if (vertical) {
+					c->set_v_size_flags(SIZE_EXPAND_FILL);
+					c->set_h_size_flags(SIZE_FILL);
+				} else {
+					c->set_v_size_flags(SIZE_FILL);
+					c->set_h_size_flags(SIZE_EXPAND_FILL);
+				}
+			}
+		}
+	}
+
+	_resort();
+}
+
 void BoxContainer::_resort() {
 	/** First pass, determine minimum size AND amount of stretchable elements */
 
@@ -205,52 +315,6 @@ void BoxContainer::_resort() {
 	}
 }
 
-Size2 BoxContainer::get_minimum_size() const {
-	/* Calculate MINIMUM SIZE */
-
-	Size2i minimum;
-	int sep = get_theme_constant("separation"); //,vertical?"VBoxContainer":"HBoxContainer");
-
-	bool first = true;
-
-	for (int i = 0; i < get_child_count(); i++) {
-		Control *c = Object::cast_to<Control>(get_child(i));
-		if (!c) {
-			continue;
-		}
-		if (c->is_set_as_toplevel()) {
-			continue;
-		}
-
-		if (!c->is_visible()) {
-			continue;
-		}
-
-		Size2i size = c->get_combined_minimum_size();
-
-		if (vertical) { /* VERTICAL */
-
-			if (size.width > minimum.width) {
-				minimum.width = size.width;
-			}
-
-			minimum.height += size.height + (first ? 0 : sep);
-
-		} else { /* HORIZONTAL */
-
-			if (size.height > minimum.height) {
-				minimum.height = size.height;
-			}
-
-			minimum.width += size.width + (first ? 0 : sep);
-		}
-
-		first = false;
-	}
-
-	return minimum;
-}
-
 void BoxContainer::_notification(int p_what) {
 	switch (p_what) {
 		case NOTIFICATION_SORT_CHILDREN: {
@@ -262,38 +326,6 @@ void BoxContainer::_notification(int p_what) {
 	}
 }
 
-void BoxContainer::set_alignment(AlignMode p_align) {
-	align = p_align;
-	_resort();
-}
-
-BoxContainer::AlignMode BoxContainer::get_alignment() const {
-	return align;
-}
-
-void BoxContainer::add_spacer(bool p_begin) {
-	Control *c = memnew(Control);
-	c->set_mouse_filter(MOUSE_FILTER_PASS); //allow spacer to pass mouse events
-
-	if (vertical) {
-		c->set_v_size_flags(SIZE_EXPAND_FILL);
-	} else {
-		c->set_h_size_flags(SIZE_EXPAND_FILL);
-	}
-
-	add_child(c);
-	if (p_begin) {
-		move_child(c, 0);
-	}
-}
-
-BoxContainer::BoxContainer(bool p_vertical) {
-	vertical = p_vertical;
-	align = ALIGN_BEGIN;
-	//set_ignore_mouse(true);
-	set_mouse_filter(MOUSE_FILTER_PASS);
-}
-
 void BoxContainer::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("add_spacer", "begin"), &BoxContainer::add_spacer);
 	ClassDB::bind_method(D_METHOD("get_alignment"), &BoxContainer::get_alignment);
@@ -320,3 +352,31 @@ MarginContainer *VBoxContainer::add_margin_child(const String &p_label, Control
 
 	return mc;
 }
+
+CBoxContainer::ContainerMode CBoxContainer::get_mode() const {
+	return _mode;
+}
+void CBoxContainer::set_mode(const ContainerMode p_mode) {
+	if (p_mode == _mode) {
+		return;
+	}
+
+	_mode = p_mode;
+
+	_set_vertical(_mode == CONTAINER_MODE_VERTICAL);
+}
+
+CBoxContainer::CBoxContainer() {
+	_mode = CONTAINER_MODE_HORIZONTAL;
+}
+CBoxContainer::~CBoxContainer() {
+}
+
+void CBoxContainer::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("get_mode"), &CBoxContainer::get_mode);
+	ClassDB::bind_method(D_METHOD("set_mode", "mode"), &CBoxContainer::set_mode);
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "mode", PROPERTY_HINT_ENUM, "Horizontal,Vertical"), "set_mode", "get_mode");
+
+	BIND_ENUM_CONSTANT(CONTAINER_MODE_HORIZONTAL);
+	BIND_ENUM_CONSTANT(CONTAINER_MODE_VERTICAL);
+}

scene/gui/box_container.h

@@ -48,18 +48,6 @@ public:
 		ALIGN_END
 	};
 
-private:
-	bool vertical;
-	AlignMode align;
-
-	void _resort();
-
-protected:
-	void _notification(int p_what);
-
-	static void _bind_methods();
-
-public:
 	void add_spacer(bool p_begin = false);
 
 	void set_alignment(AlignMode p_align);
@@ -68,6 +56,20 @@ public:
 	virtual Size2 get_minimum_size() const;
 
 	BoxContainer(bool p_vertical = false);
+
+protected:
+	bool _get_vertical() const;
+	void _set_vertical(bool p_vertical);
+
+	void _resort();
+
+	void _notification(int p_what);
+
+	static void _bind_methods();
+
+private:
+	bool vertical;
+	AlignMode align;
 };
 
 class HBoxContainer : public BoxContainer {
@@ -89,6 +91,28 @@ public:
 			BoxContainer(true) {}
 };
 
+class CBoxContainer : public BoxContainer {
+	GDCLASS(CBoxContainer, BoxContainer);
+
+public:
+	enum ContainerMode {
+		CONTAINER_MODE_HORIZONTAL = 0,
+		CONTAINER_MODE_VERTICAL,
+	};
+
+	ContainerMode get_mode() const;
+	void set_mode(const ContainerMode p_mode);
+
+	CBoxContainer();
+	~CBoxContainer();
+
+protected:
+	static void _bind_methods();
+
+	ContainerMode _mode;
+};
+
 VARIANT_ENUM_CAST(BoxContainer::AlignMode);
+VARIANT_ENUM_CAST(CBoxContainer::ContainerMode);
 
 #endif // BOX_CONTAINER_H

scene/register_scene_types.cpp

@@ -341,6 +341,7 @@ void register_scene_types() {
 	ClassDB::register_virtual_class<BoxContainer>();
 	ClassDB::register_class<HBoxContainer>();
 	ClassDB::register_class<VBoxContainer>();
+	ClassDB::register_class<CBoxContainer>();
 	ClassDB::register_class<GridContainer>();
 	ClassDB::register_class<CenterContainer>();
 	ClassDB::register_class<ScrollContainer>();