Merge pull request #53341 from pycbouh/gui-editor-scale-encapsulation

22 files changed, 805 insertions, 530 deletions

diff --git a/doc/classes/Control.xml b/doc/classes/Control.xml
index b00bf1c250..6fa59a15ac 100644
--- a/doc/classes/Control.xml
+++ b/doc/classes/Control.xml
@@ -458,6 +458,27 @@
 				See [method get_theme_color] for details.
 			</description>
 		</method>
+		<method name="get_theme_default_base_scale" qualifiers="const">
+			<return type="float" />
+			<description>
+				Returns the default base scale value from the first matching [Theme] in the tree if that [Theme] has a valid [member Theme.default_base_scale] value.
+				See [method get_theme_color] for details.
+			</description>
+		</method>
+		<method name="get_theme_default_font" qualifiers="const">
+			<return type="Font" />
+			<description>
+				Returns the default font from the first matching [Theme] in the tree if that [Theme] has a valid [member Theme.default_font] value.
+				See [method get_theme_color] for details.
+			</description>
+		</method>
+		<method name="get_theme_default_font_size" qualifiers="const">
+			<return type="int" />
+			<description>
+				Returns the default font size value from the first matching [Theme] in the tree if that [Theme] has a valid [member Theme.default_font_size] value.
+				See [method get_theme_color] for details.
+			</description>
+		</method>
 		<method name="get_theme_font" qualifiers="const">
 			<return type="Font" />
 			<argument index="0" name="name" type="StringName" />
diff --git a/doc/classes/Theme.xml b/doc/classes/Theme.xml
index edf5874432..2f5648dda9 100644
--- a/doc/classes/Theme.xml
+++ b/doc/classes/Theme.xml
@@ -273,6 +273,24 @@
 				Returns [code]false[/code] if the theme does not have [code]theme_type[/code].
 			</description>
 		</method>
+		<method name="has_default_base_scale" qualifiers="const">
+			<return type="bool" />
+			<description>
+				Returns [code]true[/code] if this theme has a valid [member default_base_scale] value.
+			</description>
+		</method>
+		<method name="has_default_font" qualifiers="const">
+			<return type="bool" />
+			<description>
+				Returns [code]true[/code] if this theme has a valid [member default_font] value.
+			</description>
+		</method>
+		<method name="has_default_font_size" qualifiers="const">
+			<return type="bool" />
+			<description>
+				Returns [code]true[/code] if this theme has a valid [member default_font_size] value.
+			</description>
+		</method>
 		<method name="has_font" qualifiers="const">
 			<return type="bool" />
 			<argument index="0" name="name" type="StringName" />
@@ -484,11 +502,17 @@
 		</method>
 	</methods>
 	<members>
+		<member name="default_base_scale" type="float" setter="set_default_base_scale" getter="get_default_base_scale" default="0.0">
+			The default base scale factor of this [Theme] resource. Used by some controls to scale their visual properties based on a global scale factor. If this value is set to [code]0.0[/code], the global scale factor is used.
+			Use [method has_default_base_scale] to check if this value is valid.
+		</member>
 		<member name="default_font" type="Font" setter="set_default_font" getter="get_default_font">
-			The theme's default font.
+			The default font of this [Theme] resource. Used as a fallback value for font items defined in this theme, but having invalid values. If this value is also invalid, the global default value is used.
+			Use [method has_default_font] to check if this value is valid.
 		</member>
 		<member name="default_font_size" type="int" setter="set_default_font_size" getter="get_default_font_size" default="-1">
-			The theme's default font size. Set to [code]-1[/code] to ignore and use global default.
+			The default font size of this [Theme] resource. Used as a fallback value for font size items defined in this theme, but having invalid values. If this value is set to [code]-1[/code], the global default value is used.
+			Use [method has_default_font_size] to check if this value is valid.
 		</member>
 	</members>
 	<constants>
diff --git a/doc/classes/Window.xml b/doc/classes/Window.xml
index 15d844aacb..0653c8b453 100644
--- a/doc/classes/Window.xml
+++ b/doc/classes/Window.xml
@@ -59,6 +59,21 @@
 			<description>
 			</description>
 		</method>
+		<method name="get_theme_default_base_scale" qualifiers="const">
+			<return type="float" />
+			<description>
+			</description>
+		</method>
+		<method name="get_theme_default_font" qualifiers="const">
+			<return type="Font" />
+			<description>
+			</description>
+		</method>
+		<method name="get_theme_default_font_size" qualifiers="const">
+			<return type="int" />
+			<description>
+			</description>
+		</method>
 		<method name="get_theme_font" qualifiers="const">
 			<return type="Font" />
 			<argument index="0" name="name" type="StringName" />
diff --git a/editor/editor_themes.cpp b/editor/editor_themes.cpp
index 0579fb4cbd..6efbcbc61e 100644
--- a/editor/editor_themes.cpp
+++ b/editor/editor_themes.cpp
@@ -292,7 +292,8 @@ void editor_register_and_generate_icons(Ref<Theme> p_theme, bool p_dark_theme =
 Ref<Theme> create_editor_theme(const Ref<Theme> p_theme) {
 	Ref<Theme> theme = Ref<Theme>(memnew(Theme));
 
-	const float default_contrast = 0.3;
+	// Controls may rely on the scale for their internal drawing logic.
+	theme->set_default_theme_base_scale(EDSCALE);
 
 	// Theme settings
 	Color accent_color = EDITOR_GET("interface/theme/accent_color");
@@ -310,6 +311,8 @@ Ref<Theme> create_editor_theme(const Ref<Theme> p_theme) {
 	Color preset_base_color;
 	float preset_contrast = 0;
 
+	const float default_contrast = 0.3;
+
 	// Please use alphabetical order if you're adding a new theme here
 	// (after "Custom")
 
diff --git a/scene/gui/color_picker.cpp b/scene/gui/color_picker.cpp
index 611035fff9..54548e1941 100644
--- a/scene/gui/color_picker.cpp
+++ b/scene/gui/color_picker.cpp
@@ -35,7 +35,6 @@
 #include "core/os/os.h"
 
 #ifdef TOOLS_ENABLED
-#include "editor/editor_scale.h"
 #include "editor/editor_settings.h"
 #endif
 #include "scene/main/window.h"
@@ -44,17 +43,7 @@ List<Color> ColorPicker::preset_cache;
 
 void ColorPicker::_notification(int p_what) {
 	switch (p_what) {
-		case NOTIFICATION_THEME_CHANGED: {
-			btn_pick->set_icon(get_theme_icon(SNAME("screen_picker"), SNAME("ColorPicker")));
-			btn_add_preset->set_icon(get_theme_icon(SNAME("add_preset")));
-			_update_presets();
-			_update_controls();
-		} break;
 		case NOTIFICATION_ENTER_TREE: {
-			btn_pick->set_icon(get_theme_icon(SNAME("screen_picker"), SNAME("ColorPicker")));
-			btn_add_preset->set_icon(get_theme_icon(SNAME("add_preset")));
-
-			_update_controls();
 			_update_color();
 
 #ifdef TOOLS_ENABLED
@@ -71,18 +60,39 @@ void ColorPicker::_notification(int p_what) {
 				}
 			}
 #endif
-		} break;
-		case NOTIFICATION_PARENTED: {
+			[[fallthrough]];
+		}
+		case NOTIFICATION_THEME_CHANGED: {
+			btn_pick->set_icon(get_theme_icon(SNAME("screen_picker"), SNAME("ColorPicker")));
+			btn_add_preset->set_icon(get_theme_icon(SNAME("add_preset")));
+
+			uv_edit->set_custom_minimum_size(Size2(get_theme_constant(SNAME("sv_width")), get_theme_constant(SNAME("sv_height"))));
+			w_edit->set_custom_minimum_size(Size2(get_theme_constant(SNAME("h_width")), 0));
+
+			wheel_edit->set_custom_minimum_size(Size2(get_theme_constant(SNAME("sv_width")), get_theme_constant(SNAME("sv_height"))));
+			wheel_margin->add_theme_constant_override("margin_bottom", 8 * get_theme_default_base_scale());
+
 			for (int i = 0; i < 4; i++) {
+				labels[i]->set_custom_minimum_size(Size2(get_theme_constant(SNAME("label_width")), 0));
 				set_offset((Side)i, get_offset((Side)i) + get_theme_constant(SNAME("margin")));
 			}
+
+			if (Engine::get_singleton()->is_editor_hint()) {
+				// Adjust for the width of the "Script" icon.
+				text_type->set_custom_minimum_size(Size2(28 * get_theme_default_base_scale(), 0));
+			}
+
+			_update_presets();
+			_update_controls();
 		} break;
+
 		case NOTIFICATION_VISIBILITY_CHANGED: {
 			Popup *p = Object::cast_to<Popup>(get_parent());
 			if (p) {
 				p->set_size(Size2(get_combined_minimum_size().width + get_theme_constant(SNAME("margin")) * 2, get_combined_minimum_size().height + get_theme_constant(SNAME("margin")) * 2));
 			}
 		} break;
+
 		case NOTIFICATION_WM_CLOSE_REQUEST: {
 			if (screen != nullptr && screen->is_visible()) {
 				screen->hide();
@@ -762,11 +772,7 @@ void ColorPicker::_slider_draw(int p_which) {
 	Size2 size = scroll[p_which]->get_size();
 	Color left_color;
 	Color right_color;
-#ifdef TOOLS_ENABLED
-	const real_t margin = 4 * EDSCALE;
-#else
-	const real_t margin = 4;
-#endif
+	const real_t margin = 4 * get_theme_default_base_scale();
 
 	if (p_which == 3) {
 		scroll[p_which]->draw_texture_rect(get_theme_icon(SNAME("sample_bg"), SNAME("ColorPicker")), Rect2(Point2(0, margin), Size2(size.x, margin)), true);
@@ -1147,7 +1153,6 @@ ColorPicker::ColorPicker() :
 	uv_edit->set_mouse_filter(MOUSE_FILTER_PASS);
 	uv_edit->set_h_size_flags(SIZE_EXPAND_FILL);
 	uv_edit->set_v_size_flags(SIZE_EXPAND_FILL);
-	uv_edit->set_custom_minimum_size(Size2(get_theme_constant(SNAME("sv_width")), get_theme_constant(SNAME("sv_height"))));
 	uv_edit->connect("draw", callable_mp(this, &ColorPicker::_hsv_draw), make_binds(0, uv_edit));
 
 	HBoxContainer *hb_smpl = memnew(HBoxContainer);
@@ -1219,9 +1224,6 @@ ColorPicker::ColorPicker() :
 	text_type->set_text("#");
 	text_type->set_tooltip(TTR("Switch between hexadecimal and code values."));
 	if (Engine::get_singleton()->is_editor_hint()) {
-#ifdef TOOLS_ENABLED
-		text_type->set_custom_minimum_size(Size2(28 * EDSCALE, 0)); // Adjust for the width of the "Script" icon.
-#endif
 		text_type->connect("pressed", callable_mp(this, &ColorPicker::_text_type_toggled));
 	} else {
 		text_type->set_flat(true);
@@ -1236,7 +1238,6 @@ ColorPicker::ColorPicker() :
 
 	wheel_edit->set_h_size_flags(SIZE_EXPAND_FILL);
 	wheel_edit->set_v_size_flags(SIZE_EXPAND_FILL);
-	wheel_edit->set_custom_minimum_size(Size2(get_theme_constant(SNAME("sv_width")), get_theme_constant(SNAME("sv_height"))));
 	hb_edit->add_child(wheel_edit);
 
 	wheel_mat.instantiate();
@@ -1244,12 +1245,7 @@ ColorPicker::ColorPicker() :
 	circle_mat.instantiate();
 	circle_mat->set_shader(circle_shader);
 
-	MarginContainer *wheel_margin(memnew(MarginContainer));
-#ifdef TOOLS_ENABLED
-	wheel_margin->add_theme_constant_override("margin_bottom", 8 * EDSCALE);
-#else
 	wheel_margin->add_theme_constant_override("margin_bottom", 8);
-#endif
 	wheel_edit->add_child(wheel_margin);
 
 	wheel_margin->add_child(wheel);
@@ -1261,7 +1257,6 @@ ColorPicker::ColorPicker() :
 	wheel_uv->connect("draw", callable_mp(this, &ColorPicker::_hsv_draw), make_binds(0, wheel_uv));
 
 	hb_edit->add_child(w_edit);
-	w_edit->set_custom_minimum_size(Size2(get_theme_constant(SNAME("h_width")), 0));
 	w_edit->set_h_size_flags(SIZE_FILL);
 	w_edit->set_v_size_flags(SIZE_EXPAND_FILL);
 	w_edit->connect("gui_input", callable_mp(this, &ColorPicker::_w_input));
diff --git a/scene/gui/color_picker.h b/scene/gui/color_picker.h
index 67ca007eb5..ad4f5ad5b1 100644
--- a/scene/gui/color_picker.h
+++ b/scene/gui/color_picker.h
@@ -81,6 +81,7 @@ private:
 	Control *uv_edit = memnew(Control);
 	Control *w_edit = memnew(Control);
 	AspectRatioContainer *wheel_edit = memnew(AspectRatioContainer);
+	MarginContainer *wheel_margin = memnew(MarginContainer);
 	Ref<ShaderMaterial> wheel_mat;
 	Ref<ShaderMaterial> circle_mat;
 	Control *wheel = memnew(Control);
diff --git a/scene/gui/control.cpp b/scene/gui/control.cpp
index 1b8b5e17ed..e2d3807b40 100644
--- a/scene/gui/control.cpp
+++ b/scene/gui/control.cpp
@@ -833,11 +833,12 @@ T Control::get_theme_item_in_types(Control *p_theme_owner, Window *p_theme_owner
 	ERR_FAIL_COND_V_MSG(p_theme_types.size() == 0, T(), "At least one theme type must be specified.");
 
 	// First, look through each control or window node in the branch, until no valid parent can be found.
-	// For each control iterate through its inheritance chain and see if p_name exists in any of them.
+	// Only nodes with a theme resource attached are considered.
 	Control *theme_owner = p_theme_owner;
 	Window *theme_owner_window = p_theme_owner_window;
 
 	while (theme_owner || theme_owner_window) {
+		// For each theme resource check the theme types provided and see if p_name exists with any of them.
 		for (const StringName &E : p_theme_types) {
 			if (theme_owner && theme_owner->data.theme->has_theme_item(p_data_type, p_name, E)) {
 				return theme_owner->data.theme->get_theme_item(p_data_type, p_name, E);
@@ -888,11 +889,12 @@ bool Control::has_theme_item_in_types(Control *p_theme_owner, Window *p_theme_ow
 	ERR_FAIL_COND_V_MSG(p_theme_types.size() == 0, false, "At least one theme type must be specified.");
 
 	// First, look through each control or window node in the branch, until no valid parent can be found.
-	// For each control iterate through its inheritance chain and see if p_name exists in any of them.
+	// Only nodes with a theme resource attached are considered.
 	Control *theme_owner = p_theme_owner;
 	Window *theme_owner_window = p_theme_owner_window;
 
 	while (theme_owner || theme_owner_window) {
+		// For each theme resource check the theme types provided and see if p_name exists with any of them.
 		for (const StringName &E : p_theme_types) {
 			if (theme_owner && theme_owner->data.theme->has_theme_item(p_data_type, p_name, E)) {
 				return true;
@@ -1130,6 +1132,150 @@ bool Control::has_theme_constant(const StringName &p_name, const StringName &p_t
 	return has_theme_item_in_types(data.theme_owner, data.theme_owner_window, Theme::DATA_TYPE_CONSTANT, p_name, theme_types);
 }
 
+float Control::fetch_theme_default_base_scale(Control *p_theme_owner, Window *p_theme_owner_window) {
+	// First, look through each control or window node in the branch, until no valid parent can be found.
+	// Only nodes with a theme resource attached are considered.
+	// For each theme resource see if their assigned theme has the default value defined and valid.
+	Control *theme_owner = p_theme_owner;
+	Window *theme_owner_window = p_theme_owner_window;
+
+	while (theme_owner || theme_owner_window) {
+		if (theme_owner && theme_owner->data.theme->has_default_theme_base_scale()) {
+			return theme_owner->data.theme->get_default_theme_base_scale();
+		}
+
+		if (theme_owner_window && theme_owner_window->theme->has_default_theme_base_scale()) {
+			return theme_owner_window->theme->get_default_theme_base_scale();
+		}
+
+		Node *parent = theme_owner ? theme_owner->get_parent() : theme_owner_window->get_parent();
+		Control *parent_c = Object::cast_to<Control>(parent);
+		if (parent_c) {
+			theme_owner = parent_c->data.theme_owner;
+			theme_owner_window = parent_c->data.theme_owner_window;
+		} else {
+			Window *parent_w = Object::cast_to<Window>(parent);
+			if (parent_w) {
+				theme_owner = parent_w->theme_owner;
+				theme_owner_window = parent_w->theme_owner_window;
+			} else {
+				theme_owner = nullptr;
+				theme_owner_window = nullptr;
+			}
+		}
+	}
+
+	// Secondly, check the project-defined Theme resource.
+	if (Theme::get_project_default().is_valid()) {
+		if (Theme::get_project_default()->has_default_theme_base_scale()) {
+			return Theme::get_project_default()->get_default_theme_base_scale();
+		}
+	}
+
+	// Lastly, fall back on the default Theme.
+	return Theme::get_default()->get_default_theme_base_scale();
+}
+
+float Control::get_theme_default_base_scale() const {
+	return fetch_theme_default_base_scale(data.theme_owner, data.theme_owner_window);
+}
+
+Ref<Font> Control::fetch_theme_default_font(Control *p_theme_owner, Window *p_theme_owner_window) {
+	// First, look through each control or window node in the branch, until no valid parent can be found.
+	// Only nodes with a theme resource attached are considered.
+	// For each theme resource see if their assigned theme has the default value defined and valid.
+	Control *theme_owner = p_theme_owner;
+	Window *theme_owner_window = p_theme_owner_window;
+
+	while (theme_owner || theme_owner_window) {
+		if (theme_owner && theme_owner->data.theme->has_default_theme_font()) {
+			return theme_owner->data.theme->get_default_theme_font();
+		}
+
+		if (theme_owner_window && theme_owner_window->theme->has_default_theme_font()) {
+			return theme_owner_window->theme->get_default_theme_font();
+		}
+
+		Node *parent = theme_owner ? theme_owner->get_parent() : theme_owner_window->get_parent();
+		Control *parent_c = Object::cast_to<Control>(parent);
+		if (parent_c) {
+			theme_owner = parent_c->data.theme_owner;
+			theme_owner_window = parent_c->data.theme_owner_window;
+		} else {
+			Window *parent_w = Object::cast_to<Window>(parent);
+			if (parent_w) {
+				theme_owner = parent_w->theme_owner;
+				theme_owner_window = parent_w->theme_owner_window;
+			} else {
+				theme_owner = nullptr;
+				theme_owner_window = nullptr;
+			}
+		}
+	}
+
+	// Secondly, check the project-defined Theme resource.
+	if (Theme::get_project_default().is_valid()) {
+		if (Theme::get_project_default()->has_default_theme_font()) {
+			return Theme::get_project_default()->get_default_theme_font();
+		}
+	}
+
+	// Lastly, fall back on the default Theme.
+	return Theme::get_default()->get_default_theme_font();
+}
+
+Ref<Font> Control::get_theme_default_font() const {
+	return fetch_theme_default_font(data.theme_owner, data.theme_owner_window);
+}
+
+int Control::fetch_theme_default_font_size(Control *p_theme_owner, Window *p_theme_owner_window) {
+	// First, look through each control or window node in the branch, until no valid parent can be found.
+	// Only nodes with a theme resource attached are considered.
+	// For each theme resource see if their assigned theme has the default value defined and valid.
+	Control *theme_owner = p_theme_owner;
+	Window *theme_owner_window = p_theme_owner_window;
+
+	while (theme_owner || theme_owner_window) {
+		if (theme_owner && theme_owner->data.theme->has_default_theme_font_size()) {
+			return theme_owner->data.theme->get_default_theme_font_size();
+		}
+
+		if (theme_owner_window && theme_owner_window->theme->has_default_theme_font_size()) {
+			return theme_owner_window->theme->get_default_theme_font_size();
+		}
+
+		Node *parent = theme_owner ? theme_owner->get_parent() : theme_owner_window->get_parent();
+		Control *parent_c = Object::cast_to<Control>(parent);
+		if (parent_c) {
+			theme_owner = parent_c->data.theme_owner;
+			theme_owner_window = parent_c->data.theme_owner_window;
+		} else {
+			Window *parent_w = Object::cast_to<Window>(parent);
+			if (parent_w) {
+				theme_owner = parent_w->theme_owner;
+				theme_owner_window = parent_w->theme_owner_window;
+			} else {
+				theme_owner = nullptr;
+				theme_owner_window = nullptr;
+			}
+		}
+	}
+
+	// Secondly, check the project-defined Theme resource.
+	if (Theme::get_project_default().is_valid()) {
+		if (Theme::get_project_default()->has_default_theme_font_size()) {
+			return Theme::get_project_default()->get_default_theme_font_size();
+		}
+	}
+
+	// Lastly, fall back on the default Theme.
+	return Theme::get_default()->get_default_theme_font_size();
+}
+
+int Control::get_theme_default_font_size() const {
+	return fetch_theme_default_font_size(data.theme_owner, data.theme_owner_window);
+}
+
 Rect2 Control::get_parent_anchorable_rect() const {
 	if (!is_inside_tree()) {
 		return Rect2();
@@ -2789,6 +2935,10 @@ void Control::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("has_theme_color", "name", "theme_type"), &Control::has_theme_color, DEFVAL(""));
 	ClassDB::bind_method(D_METHOD("has_theme_constant", "name", "theme_type"), &Control::has_theme_constant, DEFVAL(""));
 
+	ClassDB::bind_method(D_METHOD("get_theme_default_base_scale"), &Control::get_theme_default_base_scale);
+	ClassDB::bind_method(D_METHOD("get_theme_default_font"), &Control::get_theme_default_font);
+	ClassDB::bind_method(D_METHOD("get_theme_default_font_size"), &Control::get_theme_default_font_size);
+
 	ClassDB::bind_method(D_METHOD("get_parent_control"), &Control::get_parent_control);
 
 	ClassDB::bind_method(D_METHOD("set_h_grow_direction", "direction"), &Control::set_h_grow_direction);
diff --git a/scene/gui/control.h b/scene/gui/control.h
index 87ff3918cb..bdc06319ea 100644
--- a/scene/gui/control.h
+++ b/scene/gui/control.h
@@ -509,6 +509,14 @@ public:
 	bool has_theme_color(const StringName &p_name, const StringName &p_theme_type = StringName()) const;
 	bool has_theme_constant(const StringName &p_name, const StringName &p_theme_type = StringName()) const;
 
+	static float fetch_theme_default_base_scale(Control *p_theme_owner, Window *p_theme_owner_window);
+	static Ref<Font> fetch_theme_default_font(Control *p_theme_owner, Window *p_theme_owner_window);
+	static int fetch_theme_default_font_size(Control *p_theme_owner, Window *p_theme_owner_window);
+
+	float get_theme_default_base_scale() const;
+	Ref<Font> get_theme_default_font() const;
+	int get_theme_default_font_size() const;
+
 	/* TOOLTIP */
 
 	void set_tooltip(const String &p_tooltip);
diff --git a/scene/gui/dialogs.cpp b/scene/gui/dialogs.cpp
index 5d98aaa698..71d2778cc3 100644
--- a/scene/gui/dialogs.cpp
+++ b/scene/gui/dialogs.cpp
@@ -37,7 +37,6 @@
 
 #ifdef TOOLS_ENABLED
 #include "editor/editor_node.h"
-#include "editor/editor_scale.h"
 #include "scene/main/window.h" // Only used to check for more modals when dimming the editor.
 #endif
 
@@ -363,8 +362,7 @@ Button *ConfirmationDialog::get_cancel_button() {
 
 ConfirmationDialog::ConfirmationDialog() {
 	set_title(TTRC("Please Confirm..."));
-#ifdef TOOLS_ENABLED
-	set_min_size(Size2(200, 70) * EDSCALE);
-#endif
+	set_min_size(Size2(200, 70));
+
 	cancel = add_cancel_button();
 }
diff --git a/scene/gui/gradient_edit.cpp b/scene/gui/gradient_edit.cpp
index 56b8a936e1..5d024d3be7 100644
--- a/scene/gui/gradient_edit.cpp
+++ b/scene/gui/gradient_edit.cpp
@@ -32,15 +32,6 @@
 
 #include "core/os/keyboard.h"
 
-#ifdef TOOLS_ENABLED
-#include "editor/editor_scale.h"
-#define SPACING (3 * EDSCALE)
-#define POINT_WIDTH (8 * EDSCALE)
-#else
-#define SPACING 3
-#define POINT_WIDTH 8
-#endif
-
 GradientEdit::GradientEdit() {
 	set_focus_mode(FOCUS_ALL);
 
@@ -53,12 +44,12 @@ GradientEdit::GradientEdit() {
 
 int GradientEdit::_get_point_from_pos(int x) {
 	int result = -1;
-	int total_w = get_size().width - get_size().height - SPACING;
+	int total_w = get_size().width - get_size().height - draw_spacing;
 	float min_distance = 1e20;
 	for (int i = 0; i < points.size(); i++) {
 		//Check if we clicked at point
 		float distance = ABS(x - points[i].offset * total_w);
-		float min = (POINT_WIDTH / 2 * 1.7); //make it easier to grab
+		float min = (draw_point_width / 2 * 1.7); //make it easier to grab
 		if (distance <= min && distance < min_distance) {
 			result = i;
 			min_distance = distance;
@@ -129,7 +120,7 @@ void GradientEdit::gui_input(const Ref<InputEvent> &p_event) {
 		grabbed = _get_point_from_pos(x);
 
 		if (grabbed != -1) {
-			int total_w = get_size().width - get_size().height - SPACING;
+			int total_w = get_size().width - get_size().height - draw_spacing;
 			Gradient::Point newPoint = points[grabbed];
 			newPoint.offset = CLAMP(x / float(total_w), 0, 1);
 
@@ -151,10 +142,10 @@ void GradientEdit::gui_input(const Ref<InputEvent> &p_event) {
 	if (mb.is_valid() && mb->get_button_index() == 1 && mb->is_pressed()) {
 		update();
 		int x = mb->get_position().x;
-		int total_w = get_size().width - get_size().height - SPACING;
+		int total_w = get_size().width - get_size().height - draw_spacing;
 
 		//Check if color selector was clicked.
-		if (x > total_w + SPACING) {
+		if (x > total_w + draw_spacing) {
 			_show_color_picker();
 			return;
 		}
@@ -225,7 +216,7 @@ void GradientEdit::gui_input(const Ref<InputEvent> &p_event) {
 	Ref<InputEventMouseMotion> mm = p_event;
 
 	if (mm.is_valid() && grabbing) {
-		int total_w = get_size().width - get_size().height - SPACING;
+		int total_w = get_size().width - get_size().height - draw_spacing;
 
 		int x = mm->get_position().x;
 
@@ -297,6 +288,12 @@ void GradientEdit::_notification(int p_what) {
 			picker->connect("color_changed", callable_mp(this, &GradientEdit::_color_changed));
 		}
 	}
+
+	if (p_what == NOTIFICATION_ENTER_TREE || p_what == NOTIFICATION_THEME_CHANGED) {
+		draw_spacing = BASE_SPACING * get_theme_default_base_scale();
+		draw_point_width = BASE_POINT_WIDTH * get_theme_default_base_scale();
+	}
+
 	if (p_what == NOTIFICATION_DRAW) {
 		int w = get_size().x;
 		int h = get_size().y;
@@ -305,7 +302,7 @@ void GradientEdit::_notification(int p_what) {
 			return; //Safety check. We have division by 'h'. And in any case there is nothing to draw with such size
 		}
 
-		int total_w = get_size().width - get_size().height - SPACING;
+		int total_w = get_size().width - get_size().height - draw_spacing;
 
 		//Draw checker pattern for ramp
 		draw_texture_rect(get_theme_icon(SNAME("GuiMiniCheckerboard"), SNAME("EditorIcons")), Rect2(0, 0, total_w, h), true);
@@ -358,7 +355,7 @@ void GradientEdit::_notification(int p_what) {
 			col.a = 0.9;
 
 			draw_line(Vector2(points[i].offset * total_w, 0), Vector2(points[i].offset * total_w, h / 2), col);
-			Rect2 rect = Rect2(points[i].offset * total_w - POINT_WIDTH / 2, h / 2, POINT_WIDTH, h / 2);
+			Rect2 rect = Rect2(points[i].offset * total_w - draw_point_width / 2, h / 2, draw_point_width, h / 2);
 			draw_rect(rect, points[i].color, true);
 			draw_rect(rect, col, false);
 			if (grabbed == i) {
@@ -375,15 +372,15 @@ void GradientEdit::_notification(int p_what) {
 		}
 
 		//Draw "button" for color selector
-		draw_texture_rect(get_theme_icon(SNAME("GuiMiniCheckerboard"), SNAME("EditorIcons")), Rect2(total_w + SPACING, 0, h, h), true);
+		draw_texture_rect(get_theme_icon(SNAME("GuiMiniCheckerboard"), SNAME("EditorIcons")), Rect2(total_w + draw_spacing, 0, h, h), true);
 		if (grabbed != -1) {
 			//Draw with selection color
-			draw_rect(Rect2(total_w + SPACING, 0, h, h), points[grabbed].color);
+			draw_rect(Rect2(total_w + draw_spacing, 0, h, h), points[grabbed].color);
 		} else {
 			//if no color selected draw grey color with 'X' on top.
-			draw_rect(Rect2(total_w + SPACING, 0, h, h), Color(0.5, 0.5, 0.5, 1));
-			draw_line(Vector2(total_w + SPACING, 0), Vector2(total_w + SPACING + h, h), Color(1, 1, 1, 0.6));
-			draw_line(Vector2(total_w + SPACING, h), Vector2(total_w + SPACING + h, 0), Color(1, 1, 1, 0.6));
+			draw_rect(Rect2(total_w + draw_spacing, 0, h, h), Color(0.5, 0.5, 0.5, 1));
+			draw_line(Vector2(total_w + draw_spacing, 0), Vector2(total_w + draw_spacing + h, h), Color(1, 1, 1, 0.6));
+			draw_line(Vector2(total_w + draw_spacing, h), Vector2(total_w + draw_spacing + h, 0), Color(1, 1, 1, 0.6));
 		}
 
 		//Draw borders around color ramp if in focus
diff --git a/scene/gui/gradient_edit.h b/scene/gui/gradient_edit.h
index a173631963..f3a39daaf6 100644
--- a/scene/gui/gradient_edit.h
+++ b/scene/gui/gradient_edit.h
@@ -46,6 +46,13 @@ class GradientEdit : public Control {
 	int grabbed = -1;
 	Vector<Gradient::Point> points;
 
+	// Make sure to use the scaled value below.
+	const int BASE_SPACING = 3;
+	const int BASE_POINT_WIDTH = 8;
+
+	int draw_spacing = BASE_SPACING;
+	int draw_point_width = BASE_POINT_WIDTH;
+
 	void _draw_checker(int x, int y, int w, int h);
 	void _color_changed(const Color &p_color);
 	int _get_point_from_pos(int x);
diff --git a/scene/gui/graph_edit.cpp b/scene/gui/graph_edit.cpp
index d9c08ec272..35e31be9af 100644
--- a/scene/gui/graph_edit.cpp
+++ b/scene/gui/graph_edit.cpp
@@ -36,10 +36,6 @@
 #include "scene/gui/box_container.h"
 #include "scene/gui/button.h"
 
-#ifdef TOOLS_ENABLED
-#include "editor/editor_scale.h"
-#endif
-
 constexpr int MINIMAP_OFFSET = 12;
 constexpr int MINIMAP_PADDING = 5;
 
@@ -436,6 +432,8 @@ void GraphEdit::_notification(int p_what) {
 		snap_button->set_icon(get_theme_icon(SNAME("snap")));
 		minimap_button->set_icon(get_theme_icon(SNAME("minimap")));
 		layout_button->set_icon(get_theme_icon(SNAME("layout")));
+
+		zoom_label->set_custom_minimum_size(Size2(48, 0) * get_theme_default_base_scale());
 	}
 	if (p_what == NOTIFICATION_READY) {
 		Size2 hmin = h_scroll->get_combined_minimum_size();
@@ -816,11 +814,7 @@ void GraphEdit::_draw_connection_line(CanvasItem *p_where, const Vector2 &p_from
 		scaled_points.push_back(points[i] * p_zoom);
 	}
 
-#ifdef TOOLS_ENABLED
-	p_where->draw_polyline_colors(scaled_points, colors, Math::floor(p_width * EDSCALE), lines_antialiased);
-#else
-	p_where->draw_polyline_colors(scaled_points, colors, p_width, lines_antialiased);
-#endif
+	p_where->draw_polyline_colors(scaled_points, colors, Math::floor(p_width * get_theme_default_base_scale()), lines_antialiased);
 }
 
 void GraphEdit::_connections_layer_draw() {
@@ -2272,11 +2266,7 @@ GraphEdit::GraphEdit() {
 	zoom_label->set_visible(false);
 	zoom_label->set_v_size_flags(Control::SIZE_SHRINK_CENTER);
 	zoom_label->set_align(Label::ALIGN_CENTER);
-#ifdef TOOLS_ENABLED
-	zoom_label->set_custom_minimum_size(Size2(48, 0) * EDSCALE);
-#else
 	zoom_label->set_custom_minimum_size(Size2(48, 0));
-#endif
 	_update_zoom_label();
 
 	zoom_minus = memnew(Button);
diff --git a/scene/gui/line_edit.cpp b/scene/gui/line_edit.cpp
index 2c1092d8f9..653885aa08 100644
--- a/scene/gui/line_edit.cpp
+++ b/scene/gui/line_edit.cpp
@@ -40,7 +40,6 @@
 #include "servers/display_server.h"
 #include "servers/text_server.h"
 #ifdef TOOLS_ENABLED
-#include "editor/editor_scale.h"
 #include "editor/editor_settings.h"
 #endif
 #include "scene/main/window.h"
@@ -713,11 +712,7 @@ void LineEdit::_notification(int p_what) {
 				ofs_max -= r_icon->get_width();
 			}
 
-#ifdef TOOLS_ENABLED
-			int caret_width = Math::round(EDSCALE);
-#else
-			int caret_width = 1;
-#endif
+			int caret_width = Math::round(1 * get_theme_default_base_scale());
 
 			// Draw selections rects.
 			Vector2 ofs = Point2(x_ofs + scroll_offset, y_ofs);
diff --git a/scene/gui/rich_text_label.cpp b/scene/gui/rich_text_label.cpp
index bc25177275..4588966d88 100644
--- a/scene/gui/rich_text_label.cpp
+++ b/scene/gui/rich_text_label.cpp
@@ -41,10 +41,6 @@
 #include "modules/regex/regex.h"
 #endif
 
-#ifdef TOOLS_ENABLED
-#include "editor/editor_scale.h"
-#endif
-
 RichTextLabel::Item *RichTextLabel::_get_next_item(Item *p_item, bool p_free) const {
 	if (p_free) {
 		if (p_item->subitems.size()) {
@@ -995,19 +991,13 @@ int RichTextLabel::_draw_line(ItemFrame *p_frame, int p_line, const Vector2 &p_o
 				Color uc = font_color;
 				uc.a *= 0.5;
 				float y_off = TS->shaped_text_get_underline_position(rid);
-				float underline_width = TS->shaped_text_get_underline_thickness(rid);
-#ifdef TOOLS_ENABLED
-				underline_width *= EDSCALE;
-#endif
+				float underline_width = TS->shaped_text_get_underline_thickness(rid) * get_theme_default_base_scale();
 				draw_line(p_ofs + Vector2(off.x, off.y + y_off), p_ofs + Vector2(off.x + glyphs[i].advance * glyphs[i].repeat, off.y + y_off), uc, underline_width);
 			} else if (_find_strikethrough(it)) {
 				Color uc = font_color;
 				uc.a *= 0.5;
 				float y_off = -TS->shaped_text_get_ascent(rid) + TS->shaped_text_get_size(rid).y / 2;
-				float underline_width = TS->shaped_text_get_underline_thickness(rid);
-#ifdef TOOLS_ENABLED
-				underline_width *= EDSCALE;
-#endif
+				float underline_width = TS->shaped_text_get_underline_thickness(rid) * get_theme_default_base_scale();
 				draw_line(p_ofs + Vector2(off.x, off.y + y_off), p_ofs + Vector2(off.x + glyphs[i].advance * glyphs[i].repeat, off.y + y_off), uc, underline_width);
 			}
 
diff --git a/scene/gui/text_edit.cpp b/scene/gui/text_edit.cpp
index e2ddc761b8..875049ab4e 100644
--- a/scene/gui/text_edit.cpp
+++ b/scene/gui/text_edit.cpp
@@ -42,10 +42,6 @@
 
 #include "scene/main/window.h"
 
-#ifdef TOOLS_ENABLED
-#include "editor/editor_scale.h"
-#endif
-
 static bool _is_text_char(char32_t c) {
 	return !is_symbol(c);
 }
@@ -1173,12 +1169,8 @@ void TextEdit::_notification(int p_what) {
 						}
 					}
 
-					// Carets
-#ifdef TOOLS_ENABLED
-					int caret_width = Math::round(EDSCALE);
-#else
-					int caret_width = 1;
-#endif
+					// Carets.
+					int caret_width = Math::round(1 * get_theme_default_base_scale());
 
 					if (!clipped && caret.line == line && line_wrap_index == caret_wrap_index) {
 						caret.draw_pos.y = ofs_y + ldata->get_line_descent(line_wrap_index);
diff --git a/scene/gui/tree.cpp b/scene/gui/tree.cpp
index 7d7596635c..3f041bf65a 100644
--- a/scene/gui/tree.cpp
+++ b/scene/gui/tree.cpp
@@ -41,10 +41,6 @@
 
 #include "box_container.h"
 
-#ifdef TOOLS_ENABLED
-#include "editor/editor_scale.h"
-#endif
-
 #include <limits.h>
 
 Size2 TreeItem::Cell::get_icon_size() const {
@@ -1377,6 +1373,8 @@ void Tree::update_cache() {
 	cache.title_button_hover = get_theme_stylebox(SNAME("title_button_hover"));
 	cache.title_button_color = get_theme_color(SNAME("title_button_color"));
 
+	cache.base_scale = get_theme_default_base_scale();
+
 	v_scroll->set_custom_step(cache.font->get_height(cache.font_size));
 }
 
@@ -2046,15 +2044,9 @@ int Tree::draw_item(const Point2i &p_pos, const Point2 &p_draw_ofs, const Size2
 						root_pos -= Point2i(cache.arrow->get_width(), 0);
 					}
 
-					float line_width = cache.relationship_line_width;
-					float parent_line_width = cache.parent_hl_line_width;
-					float children_line_width = cache.children_hl_line_width;
-
-#ifdef TOOLS_ENABLED
-					line_width *= Math::round(EDSCALE);
-					parent_line_width *= Math::round(EDSCALE);
-					children_line_width *= Math::round(EDSCALE);
-#endif
+					float line_width = cache.relationship_line_width * Math::round(cache.base_scale);
+					float parent_line_width = cache.parent_hl_line_width * Math::round(cache.base_scale);
+					float children_line_width = cache.children_hl_line_width * Math::round(cache.base_scale);
 
 					Point2i parent_pos = Point2i(parent_ofs - cache.arrow->get_width() / 2, p_pos.y + label_h / 2 + cache.arrow->get_height() / 2) - cache.offset + p_draw_ofs;
 
diff --git a/scene/gui/tree.h b/scene/gui/tree.h
index c4a6b6b058..6ca9458e9b 100644
--- a/scene/gui/tree.h
+++ b/scene/gui/tree.h
@@ -516,6 +516,8 @@ private:
 		Color custom_button_font_highlight;
 		Color font_outline_color;
 
+		float base_scale = 1.0;
+
 		int hseparation = 0;
 		int vseparation = 0;
 		int item_margin = 0;
diff --git a/scene/main/window.cpp b/scene/main/window.cpp
index ca5a3915d0..a0f62c853f 100644
--- a/scene/main/window.cpp
+++ b/scene/main/window.cpp
@@ -1266,6 +1266,18 @@ bool Window::has_theme_constant(const StringName &p_name, const StringName &p_th
 	return Control::has_theme_item_in_types(theme_owner, theme_owner_window, Theme::DATA_TYPE_CONSTANT, p_name, theme_types);
 }
 
+float Window::get_theme_default_base_scale() const {
+	return Control::fetch_theme_default_base_scale(theme_owner, theme_owner_window);
+}
+
+Ref<Font> Window::get_theme_default_font() const {
+	return Control::fetch_theme_default_font(theme_owner, theme_owner_window);
+}
+
+int Window::get_theme_default_font_size() const {
+	return Control::fetch_theme_default_font_size(theme_owner, theme_owner_window);
+}
+
 Rect2i Window::get_parent_rect() const {
 	ERR_FAIL_COND_V(!is_inside_tree(), Rect2i());
 	if (is_embedded()) {
@@ -1480,6 +1492,10 @@ void Window::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("has_theme_color", "name", "theme_type"), &Window::has_theme_color, DEFVAL(""));
 	ClassDB::bind_method(D_METHOD("has_theme_constant", "name", "theme_type"), &Window::has_theme_constant, DEFVAL(""));
 
+	ClassDB::bind_method(D_METHOD("get_theme_default_base_scale"), &Window::get_theme_default_base_scale);
+	ClassDB::bind_method(D_METHOD("get_theme_default_font"), &Window::get_theme_default_font);
+	ClassDB::bind_method(D_METHOD("get_theme_default_font_size"), &Window::get_theme_default_font_size);
+
 	ClassDB::bind_method(D_METHOD("set_layout_direction", "direction"), &Window::set_layout_direction);
 	ClassDB::bind_method(D_METHOD("get_layout_direction"), &Window::get_layout_direction);
 	ClassDB::bind_method(D_METHOD("is_layout_rtl"), &Window::is_layout_rtl);
diff --git a/scene/main/window.h b/scene/main/window.h
index 4f31d9cd1f..def6eab7b8 100644
--- a/scene/main/window.h
+++ b/scene/main/window.h
@@ -280,6 +280,10 @@ public:
 	bool has_theme_color(const StringName &p_name, const StringName &p_theme_type = StringName()) const;
 	bool has_theme_constant(const StringName &p_name, const StringName &p_theme_type = StringName()) const;
 
+	float get_theme_default_base_scale() const;
+	Ref<Font> get_theme_default_font() const;
+	int get_theme_default_font_size() const;
+
 	Rect2i get_parent_rect() const;
 	virtual DisplayServer::WindowID get_window_id() const override;
 
diff --git a/scene/resources/default_theme/default_theme.cpp b/scene/resources/default_theme/default_theme.cpp
index 94cf826477..54bb7a82cf 100644
--- a/scene/resources/default_theme/default_theme.cpp
+++ b/scene/resources/default_theme/default_theme.cpp
@@ -1036,9 +1036,16 @@ void make_default_theme(bool p_hidpi, Ref<Font> p_font) {
 	}
 
 	Ref<Font> large_font = default_font;
-	fill_default_theme(t, default_font, large_font, default_icon, default_style, p_hidpi ? 2.0 : 1.0);
+
+	float default_scale = 1.0;
+	if (p_hidpi) {
+		default_scale = 2.0;
+	}
+
+	fill_default_theme(t, default_font, large_font, default_icon, default_style, default_scale);
 
 	Theme::set_default(t);
+	Theme::set_default_base_scale(default_scale);
 	Theme::set_default_icon(default_icon);
 	Theme::set_default_style(default_style);
 	Theme::set_default_font(default_font);
diff --git a/scene/resources/theme.cpp b/scene/resources/theme.cpp
index e49d883ba4..dd5f0b9c6c 100644
--- a/scene/resources/theme.cpp
+++ b/scene/resources/theme.cpp
@@ -29,270 +29,20 @@
 /*************************************************************************/
 
 #include "theme.h"
-#include "core/io/file_access.h"
 #include "core/string/print_string.h"
 
-void Theme::_emit_theme_changed() {
-	if (no_change_propagation) {
-		return;
-	}
-
-	notify_property_list_changed();
-	emit_changed();
-}
-
-Vector<String> Theme::_get_icon_list(const String &p_theme_type) const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_icon_list(p_theme_type, &il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_icon_type_list() const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_icon_type_list(&il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_stylebox_list(const String &p_theme_type) const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_stylebox_list(p_theme_type, &il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_stylebox_type_list() const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_stylebox_type_list(&il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_font_list(const String &p_theme_type) const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_font_list(p_theme_type, &il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_font_type_list() const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_font_type_list(&il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_font_size_list(const String &p_theme_type) const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_font_size_list(p_theme_type, &il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_font_size_type_list() const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_font_size_type_list(&il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_color_list(const String &p_theme_type) const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_color_list(p_theme_type, &il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_color_type_list() const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_color_type_list(&il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_constant_list(const String &p_theme_type) const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_constant_list(p_theme_type, &il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_constant_type_list() const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_constant_type_list(&il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_theme_item_list(DataType p_data_type, const String &p_theme_type) const {
-	switch (p_data_type) {
-		case DATA_TYPE_COLOR:
-			return _get_color_list(p_theme_type);
-		case DATA_TYPE_CONSTANT:
-			return _get_constant_list(p_theme_type);
-		case DATA_TYPE_FONT:
-			return _get_font_list(p_theme_type);
-		case DATA_TYPE_FONT_SIZE:
-			return _get_font_size_list(p_theme_type);
-		case DATA_TYPE_ICON:
-			return _get_icon_list(p_theme_type);
-		case DATA_TYPE_STYLEBOX:
-			return _get_stylebox_list(p_theme_type);
-		case DATA_TYPE_MAX:
-			break; // Can't happen, but silences warning.
-	}
-
-	return Vector<String>();
-}
-
-Vector<String> Theme::_get_theme_item_type_list(DataType p_data_type) const {
-	switch (p_data_type) {
-		case DATA_TYPE_COLOR:
-			return _get_color_type_list();
-		case DATA_TYPE_CONSTANT:
-			return _get_constant_type_list();
-		case DATA_TYPE_FONT:
-			return _get_font_type_list();
-		case DATA_TYPE_FONT_SIZE:
-			return _get_font_size_type_list();
-		case DATA_TYPE_ICON:
-			return _get_icon_type_list();
-		case DATA_TYPE_STYLEBOX:
-			return _get_stylebox_type_list();
-		case DATA_TYPE_MAX:
-			break; // Can't happen, but silences warning.
-	}
-
-	return Vector<String>();
-}
-
-Vector<String> Theme::_get_type_variation_list(const StringName &p_theme_type) const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_type_variation_list(p_theme_type, &il);
-	ilret.resize(il.size());
-
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
-
-Vector<String> Theme::_get_type_list() const {
-	Vector<String> ilret;
-	List<StringName> il;
-
-	get_type_list(&il);
-	ilret.resize(il.size());
+// Universal Theme resources used when no other theme has the item.
+Ref<Theme> Theme::default_theme;
+Ref<Theme> Theme::project_default_theme;
 
-	int i = 0;
-	String *w = ilret.ptrw();
-	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
-		w[i] = E->get();
-	}
-	return ilret;
-}
+// Universal default values, final fallback for every theme.
+float Theme::default_base_scale = 1.0;
+Ref<Texture2D> Theme::default_icon;
+Ref<StyleBox> Theme::default_style;
+Ref<Font> Theme::default_font;
+int Theme::default_font_size = 16;
 
+// Dynamic properties.
 bool Theme::_set(const StringName &p_name, const Variant &p_value) {
 	String sname = p_name;
 
@@ -452,6 +202,63 @@ void Theme::_get_property_list(List<PropertyInfo> *p_list) const {
 	}
 }
 
+// Universal fallback Theme resources.
+Ref<Theme> Theme::get_default() {
+	return default_theme;
+}
+
+void Theme::set_default(const Ref<Theme> &p_default) {
+	default_theme = p_default;
+}
+
+Ref<Theme> Theme::get_project_default() {
+	return project_default_theme;
+}
+
+void Theme::set_project_default(const Ref<Theme> &p_project_default) {
+	project_default_theme = p_project_default;
+}
+
+// Universal fallback values for theme item types.
+void Theme::set_default_base_scale(float p_base_scale) {
+	default_base_scale = p_base_scale;
+}
+
+void Theme::set_default_icon(const Ref<Texture2D> &p_icon) {
+	default_icon = p_icon;
+}
+
+void Theme::set_default_style(const Ref<StyleBox> &p_style) {
+	default_style = p_style;
+}
+
+void Theme::set_default_font(const Ref<Font> &p_font) {
+	default_font = p_font;
+}
+
+void Theme::set_default_font_size(int p_font_size) {
+	default_font_size = p_font_size;
+}
+
+// Fallback values for theme item types, configurable per theme.
+void Theme::set_default_theme_base_scale(float p_base_scale) {
+	if (default_theme_base_scale == p_base_scale) {
+		return;
+	}
+
+	default_theme_base_scale = p_base_scale;
+
+	_emit_theme_changed();
+}
+
+float Theme::get_default_theme_base_scale() const {
+	return default_theme_base_scale;
+}
+
+bool Theme::has_default_theme_base_scale() const {
+	return default_theme_base_scale > 0.0;
+}
+
 void Theme::set_default_theme_font(const Ref<Font> &p_default_font) {
 	if (default_theme_font == p_default_font) {
 		return;
@@ -474,6 +281,10 @@ Ref<Font> Theme::get_default_theme_font() const {
 	return default_theme_font;
 }
 
+bool Theme::has_default_theme_font() const {
+	return default_theme_font.is_valid();
+}
+
 void Theme::set_default_theme_font_size(int p_font_size) {
 	if (default_theme_font_size == p_font_size) {
 		return;
@@ -488,45 +299,11 @@ int Theme::get_default_theme_font_size() const {
 	return default_theme_font_size;
 }
 
-Ref<Theme> Theme::project_default_theme;
-Ref<Theme> Theme::default_theme;
-Ref<Texture2D> Theme::default_icon;
-Ref<StyleBox> Theme::default_style;
-Ref<Font> Theme::default_font;
-int Theme::default_font_size = 16;
-
-Ref<Theme> Theme::get_default() {
-	return default_theme;
-}
-
-void Theme::set_default(const Ref<Theme> &p_default) {
-	default_theme = p_default;
-}
-
-Ref<Theme> Theme::get_project_default() {
-	return project_default_theme;
-}
-
-void Theme::set_project_default(const Ref<Theme> &p_project_default) {
-	project_default_theme = p_project_default;
-}
-
-void Theme::set_default_icon(const Ref<Texture2D> &p_icon) {
-	default_icon = p_icon;
-}
-
-void Theme::set_default_style(const Ref<StyleBox> &p_style) {
-	default_style = p_style;
-}
-
-void Theme::set_default_font(const Ref<Font> &p_font) {
-	default_font = p_font;
-}
-
-void Theme::set_default_font_size(int p_font_size) {
-	default_font_size = p_font_size;
+bool Theme::has_default_theme_font_size() const {
+	return default_theme_font_size > 0;
 }
 
+// Icons.
 void Theme::set_icon(const StringName &p_name, const StringName &p_theme_type, const Ref<Texture2D> &p_icon) {
 	if (icon_map[p_theme_type].has(p_name) && icon_map[p_theme_type][p_name].is_valid()) {
 		icon_map[p_theme_type][p_name]->disconnect("changed", callable_mp(this, &Theme::_emit_theme_changed));
@@ -611,6 +388,7 @@ void Theme::get_icon_type_list(List<StringName> *p_list) const {
 	}
 }
 
+// Styleboxes.
 void Theme::set_stylebox(const StringName &p_name, const StringName &p_theme_type, const Ref<StyleBox> &p_style) {
 	if (style_map[p_theme_type].has(p_name) && style_map[p_theme_type][p_name].is_valid()) {
 		style_map[p_theme_type][p_name]->disconnect("changed", callable_mp(this, &Theme::_emit_theme_changed));
@@ -695,6 +473,7 @@ void Theme::get_stylebox_type_list(List<StringName> *p_list) const {
 	}
 }
 
+// Fonts.
 void Theme::set_font(const StringName &p_name, const StringName &p_theme_type, const Ref<Font> &p_font) {
 	if (font_map[p_theme_type][p_name].is_valid()) {
 		font_map[p_theme_type][p_name]->disconnect("changed", callable_mp(this, &Theme::_emit_theme_changed));
@@ -712,7 +491,7 @@ void Theme::set_font(const StringName &p_name, const StringName &p_theme_type, c
 Ref<Font> Theme::get_font(const StringName &p_name, const StringName &p_theme_type) const {
 	if (font_map.has(p_theme_type) && font_map[p_theme_type].has(p_name) && font_map[p_theme_type][p_name].is_valid()) {
 		return font_map[p_theme_type][p_name];
-	} else if (default_theme_font.is_valid()) {
+	} else if (has_default_theme_font()) {
 		return default_theme_font;
 	} else {
 		return default_font;
@@ -720,7 +499,7 @@ Ref<Font> Theme::get_font(const StringName &p_name, const StringName &p_theme_ty
 }
 
 bool Theme::has_font(const StringName &p_name, const StringName &p_theme_type) const {
-	return ((font_map.has(p_theme_type) && font_map[p_theme_type].has(p_name) && font_map[p_theme_type][p_name].is_valid()) || default_theme_font.is_valid());
+	return ((font_map.has(p_theme_type) && font_map[p_theme_type].has(p_name) && font_map[p_theme_type][p_name].is_valid()) || has_default_theme_font());
 }
 
 bool Theme::has_font_nocheck(const StringName &p_name, const StringName &p_theme_type) const {
@@ -781,6 +560,7 @@ void Theme::get_font_type_list(List<StringName> *p_list) const {
 	}
 }
 
+// Font sizes.
 void Theme::set_font_size(const StringName &p_name, const StringName &p_theme_type, int p_font_size) {
 	font_size_map[p_theme_type][p_name] = p_font_size;
 
@@ -790,7 +570,7 @@ void Theme::set_font_size(const StringName &p_name, const StringName &p_theme_ty
 int Theme::get_font_size(const StringName &p_name, const StringName &p_theme_type) const {
 	if (font_size_map.has(p_theme_type) && font_size_map[p_theme_type].has(p_name) && (font_size_map[p_theme_type][p_name] > 0)) {
 		return font_size_map[p_theme_type][p_name];
-	} else if (default_theme_font_size > 0) {
+	} else if (has_default_theme_font_size()) {
 		return default_theme_font_size;
 	} else {
 		return default_font_size;
@@ -798,7 +578,7 @@ int Theme::get_font_size(const StringName &p_name, const StringName &p_theme_typ
 }
 
 bool Theme::has_font_size(const StringName &p_name, const StringName &p_theme_type) const {
-	return ((font_size_map.has(p_theme_type) && font_size_map[p_theme_type].has(p_name) && (font_size_map[p_theme_type][p_name] > 0)) || (default_theme_font_size > 0));
+	return ((font_size_map.has(p_theme_type) && font_size_map[p_theme_type].has(p_name) && (font_size_map[p_theme_type][p_name] > 0)) || has_default_theme_font_size());
 }
 
 bool Theme::has_font_size_nocheck(const StringName &p_name, const StringName &p_theme_type) const {
@@ -855,6 +635,7 @@ void Theme::get_font_size_type_list(List<StringName> *p_list) const {
 	}
 }
 
+// Colors.
 void Theme::set_color(const StringName &p_name, const StringName &p_theme_type, const Color &p_color) {
 	color_map[p_theme_type][p_name] = p_color;
 
@@ -927,6 +708,7 @@ void Theme::get_color_type_list(List<StringName> *p_list) const {
 	}
 }
 
+// Theme constants.
 void Theme::set_constant(const StringName &p_name, const StringName &p_theme_type, int p_constant) {
 	constant_map[p_theme_type][p_name] = p_constant;
 
@@ -999,6 +781,7 @@ void Theme::get_constant_type_list(List<StringName> *p_list) const {
 	}
 }
 
+// Generic methods for managing theme items.
 void Theme::set_theme_item(DataType p_data_type, const StringName &p_name, const StringName &p_theme_type, const Variant &p_value) {
 	switch (p_data_type) {
 		case DATA_TYPE_COLOR: {
@@ -1230,6 +1013,7 @@ void Theme::get_theme_item_type_list(DataType p_data_type, List<StringName> *p_l
 	}
 }
 
+// Theme type variations.
 void Theme::set_type_variation(const StringName &p_theme_type, const StringName &p_base_type) {
 	ERR_FAIL_COND_MSG(p_theme_type == StringName(), "An empty theme type cannot be marked as a variation of another type.");
 	ERR_FAIL_COND_MSG(ClassDB::class_exists(p_theme_type), "A type associated with a built-in class cannot be marked as a variation of another type.");
@@ -1287,66 +1071,352 @@ void Theme::get_type_variation_list(const StringName &p_base_type, List<StringNa
 	}
 }
 
-void Theme::_freeze_change_propagation() {
-	no_change_propagation = true;
-}
+// Theme types.
+void Theme::get_type_list(List<StringName> *p_list) const {
+	ERR_FAIL_NULL(p_list);
 
-void Theme::_unfreeze_and_propagate_changes() {
-	no_change_propagation = false;
-	_emit_theme_changed();
+	Set<StringName> types;
+	const StringName *key = nullptr;
+
+	// Icons.
+	while ((key = icon_map.next(key))) {
+		types.insert(*key);
+	}
+
+	key = nullptr;
+
+	// StyleBoxes.
+	while ((key = style_map.next(key))) {
+		types.insert(*key);
+	}
+
+	key = nullptr;
+
+	// Fonts.
+	while ((key = font_map.next(key))) {
+		types.insert(*key);
+	}
+
+	key = nullptr;
+
+	// Font sizes.
+	while ((key = font_size_map.next(key))) {
+		types.insert(*key);
+	}
+
+	key = nullptr;
+
+	// Colors.
+	while ((key = color_map.next(key))) {
+		types.insert(*key);
+	}
+
+	key = nullptr;
+
+	// Constants.
+	while ((key = constant_map.next(key))) {
+		types.insert(*key);
+	}
+
+	for (Set<StringName>::Element *E = types.front(); E; E = E->next()) {
+		p_list->push_back(E->get());
+	}
 }
 
-void Theme::clear() {
-	// These items need disconnecting.
-	{
-		const StringName *K = nullptr;
-		while ((K = icon_map.next(K))) {
-			const StringName *L = nullptr;
-			while ((L = icon_map[*K].next(L))) {
-				Ref<Texture2D> icon = icon_map[*K][*L];
-				if (icon.is_valid()) {
-					icon->disconnect("changed", callable_mp(this, &Theme::_emit_theme_changed));
-				}
+void Theme::get_type_dependencies(const StringName &p_base_type, const StringName &p_type_variation, List<StringName> *p_list) {
+	ERR_FAIL_NULL(p_list);
+
+	// Build the dependency chain for type variations.
+	if (p_type_variation != StringName()) {
+		StringName variation_name = p_type_variation;
+		while (variation_name != StringName()) {
+			p_list->push_back(variation_name);
+			variation_name = get_type_variation_base(variation_name);
+
+			// If we have reached the base type dependency, it's safe to stop (assuming no funny business was done to the Theme).
+			if (variation_name == p_base_type) {
+				break;
 			}
 		}
 	}
 
-	{
-		const StringName *K = nullptr;
-		while ((K = style_map.next(K))) {
-			const StringName *L = nullptr;
-			while ((L = style_map[*K].next(L))) {
-				Ref<StyleBox> style = style_map[*K][*L];
-				if (style.is_valid()) {
-					style->disconnect("changed", callable_mp(this, &Theme::_emit_theme_changed));
-				}
-			}
-		}
+	// Continue building the chain using native class hierarchy.
+	StringName class_name = p_base_type;
+	while (class_name != StringName()) {
+		p_list->push_back(class_name);
+		class_name = ClassDB::get_parent_class_nocheck(class_name);
 	}
+}
 
-	{
-		const StringName *K = nullptr;
-		while ((K = font_map.next(K))) {
-			const StringName *L = nullptr;
-			while ((L = font_map[*K].next(L))) {
-				Ref<Font> font = font_map[*K][*L];
-				if (font.is_valid()) {
-					font->disconnect("changed", callable_mp(this, &Theme::_emit_theme_changed));
-				}
-			}
-		}
+// Internal methods for getting lists as a Vector of String (compatible with public API).
+Vector<String> Theme::_get_icon_list(const String &p_theme_type) const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_icon_list(p_theme_type, &il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
 	}
+	return ilret;
+}
 
-	icon_map.clear();
-	style_map.clear();
-	font_map.clear();
-	font_size_map.clear();
-	color_map.clear();
-	constant_map.clear();
+Vector<String> Theme::_get_icon_type_list() const {
+	Vector<String> ilret;
+	List<StringName> il;
 
-	variation_map.clear();
-	variation_base_map.clear();
+	get_icon_type_list(&il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_stylebox_list(const String &p_theme_type) const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_stylebox_list(p_theme_type, &il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_stylebox_type_list() const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_stylebox_type_list(&il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_font_list(const String &p_theme_type) const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_font_list(p_theme_type, &il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_font_type_list() const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_font_type_list(&il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_font_size_list(const String &p_theme_type) const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_font_size_list(p_theme_type, &il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_font_size_type_list() const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_font_size_type_list(&il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_color_list(const String &p_theme_type) const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_color_list(p_theme_type, &il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_color_type_list() const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_color_type_list(&il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_constant_list(const String &p_theme_type) const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_constant_list(p_theme_type, &il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_constant_type_list() const {
+	Vector<String> ilret;
+	List<StringName> il;
 
+	get_constant_type_list(&il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_theme_item_list(DataType p_data_type, const String &p_theme_type) const {
+	switch (p_data_type) {
+		case DATA_TYPE_COLOR:
+			return _get_color_list(p_theme_type);
+		case DATA_TYPE_CONSTANT:
+			return _get_constant_list(p_theme_type);
+		case DATA_TYPE_FONT:
+			return _get_font_list(p_theme_type);
+		case DATA_TYPE_FONT_SIZE:
+			return _get_font_size_list(p_theme_type);
+		case DATA_TYPE_ICON:
+			return _get_icon_list(p_theme_type);
+		case DATA_TYPE_STYLEBOX:
+			return _get_stylebox_list(p_theme_type);
+		case DATA_TYPE_MAX:
+			break; // Can't happen, but silences warning.
+	}
+
+	return Vector<String>();
+}
+
+Vector<String> Theme::_get_theme_item_type_list(DataType p_data_type) const {
+	switch (p_data_type) {
+		case DATA_TYPE_COLOR:
+			return _get_color_type_list();
+		case DATA_TYPE_CONSTANT:
+			return _get_constant_type_list();
+		case DATA_TYPE_FONT:
+			return _get_font_type_list();
+		case DATA_TYPE_FONT_SIZE:
+			return _get_font_size_type_list();
+		case DATA_TYPE_ICON:
+			return _get_icon_type_list();
+		case DATA_TYPE_STYLEBOX:
+			return _get_stylebox_type_list();
+		case DATA_TYPE_MAX:
+			break; // Can't happen, but silences warning.
+	}
+
+	return Vector<String>();
+}
+
+Vector<String> Theme::_get_type_variation_list(const StringName &p_theme_type) const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_type_variation_list(p_theme_type, &il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+Vector<String> Theme::_get_type_list() const {
+	Vector<String> ilret;
+	List<StringName> il;
+
+	get_type_list(&il);
+	ilret.resize(il.size());
+
+	int i = 0;
+	String *w = ilret.ptrw();
+	for (List<StringName>::Element *E = il.front(); E; E = E->next(), i++) {
+		w[i] = E->get();
+	}
+	return ilret;
+}
+
+// Theme bulk manipulations.
+void Theme::_emit_theme_changed() {
+	if (no_change_propagation) {
+		return;
+	}
+
+	notify_property_list_changed();
+	emit_changed();
+}
+
+void Theme::_freeze_change_propagation() {
+	no_change_propagation = true;
+}
+
+void Theme::_unfreeze_and_propagate_changes() {
+	no_change_propagation = false;
 	_emit_theme_changed();
 }
 
@@ -1434,80 +1504,58 @@ void Theme::merge_with(const Ref<Theme> &p_other) {
 	_unfreeze_and_propagate_changes();
 }
 
-void Theme::get_type_list(List<StringName> *p_list) const {
-	ERR_FAIL_NULL(p_list);
-
-	Set<StringName> types;
-	const StringName *key = nullptr;
-
-	// Icons.
-	while ((key = icon_map.next(key))) {
-		types.insert(*key);
-	}
-
-	key = nullptr;
-
-	// StyleBoxes.
-	while ((key = style_map.next(key))) {
-		types.insert(*key);
-	}
-
-	key = nullptr;
-
-	// Fonts.
-	while ((key = font_map.next(key))) {
-		types.insert(*key);
-	}
-
-	key = nullptr;
-
-	// Font sizes.
-	while ((key = font_size_map.next(key))) {
-		types.insert(*key);
-	}
-
-	key = nullptr;
-
-	// Colors.
-	while ((key = color_map.next(key))) {
-		types.insert(*key);
-	}
-
-	key = nullptr;
-
-	// Constants.
-	while ((key = constant_map.next(key))) {
-		types.insert(*key);
+void Theme::clear() {
+	// These items need disconnecting.
+	{
+		const StringName *K = nullptr;
+		while ((K = icon_map.next(K))) {
+			const StringName *L = nullptr;
+			while ((L = icon_map[*K].next(L))) {
+				Ref<Texture2D> icon = icon_map[*K][*L];
+				if (icon.is_valid()) {
+					icon->disconnect("changed", callable_mp(this, &Theme::_emit_theme_changed));
+				}
+			}
+		}
 	}
 
-	for (Set<StringName>::Element *E = types.front(); E; E = E->next()) {
-		p_list->push_back(E->get());
+	{
+		const StringName *K = nullptr;
+		while ((K = style_map.next(K))) {
+			const StringName *L = nullptr;
+			while ((L = style_map[*K].next(L))) {
+				Ref<StyleBox> style = style_map[*K][*L];
+				if (style.is_valid()) {
+					style->disconnect("changed", callable_mp(this, &Theme::_emit_theme_changed));
+				}
+			}
+		}
 	}
-}
-
-void Theme::get_type_dependencies(const StringName &p_base_type, const StringName &p_type_variation, List<StringName> *p_list) {
-	ERR_FAIL_NULL(p_list);
 
-	// Build the dependency chain for type variations.
-	if (p_type_variation != StringName()) {
-		StringName variation_name = p_type_variation;
-		while (variation_name != StringName()) {
-			p_list->push_back(variation_name);
-			variation_name = get_type_variation_base(variation_name);
-
-			// If we have reached the base type dependency, it's safe to stop (assuming no funny business was done to the Theme).
-			if (variation_name == p_base_type) {
-				break;
+	{
+		const StringName *K = nullptr;
+		while ((K = font_map.next(K))) {
+			const StringName *L = nullptr;
+			while ((L = font_map[*K].next(L))) {
+				Ref<Font> font = font_map[*K][*L];
+				if (font.is_valid()) {
+					font->disconnect("changed", callable_mp(this, &Theme::_emit_theme_changed));
+				}
 			}
 		}
 	}
 
-	// Continue building the chain using native class hierarchy.
-	StringName class_name = p_base_type;
-	while (class_name != StringName()) {
-		p_list->push_back(class_name);
-		class_name = ClassDB::get_parent_class_nocheck(class_name);
-	}
+	icon_map.clear();
+	style_map.clear();
+	font_map.clear();
+	font_size_map.clear();
+	color_map.clear();
+	constant_map.clear();
+
+	variation_map.clear();
+	variation_base_map.clear();
+
+	_emit_theme_changed();
 }
 
 void Theme::reset_state() {
@@ -1563,11 +1611,17 @@ void Theme::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_constant_list", "theme_type"), &Theme::_get_constant_list);
 	ClassDB::bind_method(D_METHOD("get_constant_type_list"), &Theme::_get_constant_type_list);
 
+	ClassDB::bind_method(D_METHOD("set_default_base_scale", "font_size"), &Theme::set_default_theme_base_scale);
+	ClassDB::bind_method(D_METHOD("get_default_base_scale"), &Theme::get_default_theme_base_scale);
+	ClassDB::bind_method(D_METHOD("has_default_base_scale"), &Theme::has_default_theme_base_scale);
+
 	ClassDB::bind_method(D_METHOD("set_default_font", "font"), &Theme::set_default_theme_font);
 	ClassDB::bind_method(D_METHOD("get_default_font"), &Theme::get_default_theme_font);
+	ClassDB::bind_method(D_METHOD("has_default_font"), &Theme::has_default_theme_font);
 
 	ClassDB::bind_method(D_METHOD("set_default_font_size", "font_size"), &Theme::set_default_theme_font_size);
 	ClassDB::bind_method(D_METHOD("get_default_font_size"), &Theme::get_default_theme_font_size);
+	ClassDB::bind_method(D_METHOD("has_default_font_size"), &Theme::has_default_theme_font_size);
 
 	ClassDB::bind_method(D_METHOD("set_theme_item", "data_type", "name", "theme_type", "value"), &Theme::set_theme_item);
 	ClassDB::bind_method(D_METHOD("get_theme_item", "data_type", "name", "theme_type"), &Theme::get_theme_item);
@@ -1588,6 +1642,7 @@ void Theme::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("merge_with", "other"), &Theme::merge_with);
 	ClassDB::bind_method(D_METHOD("clear"), &Theme::clear);
 
+	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "default_base_scale", PROPERTY_HINT_RANGE, "0.0,2.0,0.01,or_greater"), "set_default_base_scale", "get_default_base_scale");
 	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "default_font", PROPERTY_HINT_RESOURCE_TYPE, "Font"), "set_default_font", "get_default_font");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "default_font_size"), "set_default_font_size", "get_default_font_size");
 
diff --git a/scene/resources/theme.h b/scene/resources/theme.h
index 15f21b91b8..50466d99c2 100644
--- a/scene/resources/theme.h
+++ b/scene/resources/theme.h
@@ -96,13 +96,19 @@ protected:
 	bool _get(const StringName &p_name, Variant &r_ret) const;
 	void _get_property_list(List<PropertyInfo> *p_list) const;
 
-	static Ref<Theme> project_default_theme;
+	// Universal Theme resources used when no other theme has the item.
 	static Ref<Theme> default_theme;
+	static Ref<Theme> project_default_theme;
+
+	// Universal default values, final fallback for every theme.
+	static float default_base_scale;
 	static Ref<Texture2D> default_icon;
 	static Ref<StyleBox> default_style;
 	static Ref<Font> default_font;
 	static int default_font_size;
 
+	// Default values configurable for each individual theme.
+	float default_theme_base_scale = 0.0;
 	Ref<Font> default_theme_font;
 	int default_theme_font_size = -1;
 
@@ -120,16 +126,23 @@ public:
 	static Ref<Theme> get_project_default();
 	static void set_project_default(const Ref<Theme> &p_project_default);
 
+	static void set_default_base_scale(float p_base_scale);
 	static void set_default_icon(const Ref<Texture2D> &p_icon);
 	static void set_default_style(const Ref<StyleBox> &p_style);
 	static void set_default_font(const Ref<Font> &p_font);
 	static void set_default_font_size(int p_font_size);
 
+	void set_default_theme_base_scale(float p_base_scale);
+	float get_default_theme_base_scale() const;
+	bool has_default_theme_base_scale() const;
+
 	void set_default_theme_font(const Ref<Font> &p_default_font);
 	Ref<Font> get_default_theme_font() const;
+	bool has_default_theme_font() const;
 
 	void set_default_theme_font_size(int p_font_size);
 	int get_default_theme_font_size() const;
+	bool has_default_theme_font_size() const;
 
 	void set_icon(const StringName &p_name, const StringName &p_theme_type, const Ref<Texture2D> &p_icon);
 	Ref<Texture2D> get_icon(const StringName &p_name, const StringName &p_theme_type) const;