Use BitField<> in core type masks

* All core types masks are now correctly marked as bitfields.
* The enum hacks in MouseButtonMask and many other types are gone. This ensures that binders to other languages non C++ can actually implement type safe bitmasks.
* Most bitmask operations replaced by functions in BitField<>
* Key is still a problem because its enum and mask at the same time. While it kind of works in C++, this most likely can't be implemented safely in other languages and will have to be changed at some point. Mostly left as-is.
* Documentation and API dump updated to reflect bitfields in core types.

11 files changed, 36 insertions, 35 deletions

diff --git a/scene/gui/base_button.cpp b/scene/gui/base_button.cpp
index 4c27cf4b21..9cc25bf743 100644
--- a/scene/gui/base_button.cpp
+++ b/scene/gui/base_button.cpp
@@ -62,7 +62,7 @@ void BaseButton::gui_input(const Ref<InputEvent> &p_event) {
 	Ref<InputEventMouseButton> mouse_button = p_event;
 	bool ui_accept = p_event->is_action("ui_accept", true) && !p_event->is_echo();
 
-	bool button_masked = mouse_button.is_valid() && (mouse_button_to_mask(mouse_button->get_button_index()) & button_mask) != MouseButton::NONE;
+	bool button_masked = mouse_button.is_valid() && button_mask.has_flag(mouse_button_to_mask(mouse_button->get_button_index()));
 	if (button_masked || ui_accept) {
 		was_mouse_pressed = button_masked;
 		on_action_event(p_event);
@@ -323,11 +323,11 @@ BaseButton::ActionMode BaseButton::get_action_mode() const {
 	return action_mode;
 }
 
-void BaseButton::set_button_mask(MouseButton p_mask) {
+void BaseButton::set_button_mask(BitField<MouseButtonMask> p_mask) {
 	button_mask = p_mask;
 }
 
-MouseButton BaseButton::get_button_mask() const {
+BitField<MouseButtonMask> BaseButton::get_button_mask() const {
 	return button_mask;
 }
 
diff --git a/scene/gui/base_button.h b/scene/gui/base_button.h
index d7e6b68517..f5a7ce5c82 100644
--- a/scene/gui/base_button.h
+++ b/scene/gui/base_button.h
@@ -46,7 +46,7 @@ public:
 	};
 
 private:
-	MouseButton button_mask = MouseButton::MASK_LEFT;
+	BitField<MouseButtonMask> button_mask;
 	bool toggle_mode = false;
 	bool shortcut_in_tooltip = true;
 	bool was_mouse_pressed = false;
@@ -122,8 +122,8 @@ public:
 	void set_keep_pressed_outside(bool p_on);
 	bool is_keep_pressed_outside() const;
 
-	void set_button_mask(MouseButton p_mask);
-	MouseButton get_button_mask() const;
+	void set_button_mask(BitField<MouseButtonMask> p_mask);
+	BitField<MouseButtonMask> get_button_mask() const;
 
 	void set_shortcut(const Ref<Shortcut> &p_shortcut);
 	Ref<Shortcut> get_shortcut() const;
diff --git a/scene/gui/code_edit.cpp b/scene/gui/code_edit.cpp
index a68dfa80ba..680e4260e7 100644
--- a/scene/gui/code_edit.cpp
+++ b/scene/gui/code_edit.cpp
@@ -380,13 +380,13 @@ void CodeEdit::gui_input(const Ref<InputEvent> &p_gui_input) {
 		}
 
 		if (symbol_lookup_on_click_enabled) {
-			if (mm->is_command_or_control_pressed() && mm->get_button_mask() == MouseButton::NONE) {
+			if (mm->is_command_or_control_pressed() && mm->get_button_mask().is_empty()) {
 				symbol_lookup_pos = get_line_column_at_pos(mpos);
 				symbol_lookup_new_word = get_word_at_pos(mpos);
 				if (symbol_lookup_new_word != symbol_lookup_word) {
 					emit_signal(SNAME("symbol_validate"), symbol_lookup_new_word);
 				}
-			} else if (!mm->is_command_or_control_pressed() || (mm->get_button_mask() != MouseButton::NONE && symbol_lookup_pos != get_line_column_at_pos(mpos))) {
+			} else if (!mm->is_command_or_control_pressed() || (!mm->get_button_mask().is_empty() && symbol_lookup_pos != get_line_column_at_pos(mpos))) {
 				set_symbol_lookup_word_as_valid(false);
 			}
 		}
diff --git a/scene/gui/line_edit.cpp b/scene/gui/line_edit.cpp
index ab96e2c557..e5bb64b225 100644
--- a/scene/gui/line_edit.cpp
+++ b/scene/gui/line_edit.cpp
@@ -394,7 +394,7 @@ void LineEdit::gui_input(const Ref<InputEvent> &p_event) {
 			}
 		}
 
-		if ((m->get_button_mask() & MouseButton::MASK_LEFT) != MouseButton::NONE) {
+		if (m->get_button_mask().has_flag(MouseButtonMask::LEFT)) {
 			if (selection.creating) {
 				set_caret_at_pixel_pos(m->get_position().x);
 				selection_fill_at_caret();
diff --git a/scene/gui/popup_menu.cpp b/scene/gui/popup_menu.cpp
index 942e6fac7f..4fc0e5b05e 100644
--- a/scene/gui/popup_menu.cpp
+++ b/scene/gui/popup_menu.cpp
@@ -395,10 +395,10 @@ void PopupMenu::gui_input(const Ref<InputEvent> &p_event) {
 			// Activate the item on release of either the left mouse button or
 			// any mouse button held down when the popup was opened.
 			// This allows for opening the popup and triggering an action in a single mouse click.
-			if (button_idx == MouseButton::LEFT || (initial_button_mask & mouse_button_to_mask(button_idx)) != MouseButton::NONE) {
+			if (button_idx == MouseButton::LEFT || initial_button_mask.has_flag(mouse_button_to_mask(button_idx))) {
 				bool was_during_grabbed_click = during_grabbed_click;
 				during_grabbed_click = false;
-				initial_button_mask = MouseButton::NONE;
+				initial_button_mask.clear();
 
 				// Disable clicks under a time threshold to avoid selection right when opening the popup.
 				uint64_t now = OS::get_singleton()->get_ticks_msec();
diff --git a/scene/gui/popup_menu.h b/scene/gui/popup_menu.h
index 1e56f8c192..94bb93c867 100644
--- a/scene/gui/popup_menu.h
+++ b/scene/gui/popup_menu.h
@@ -92,7 +92,7 @@ class PopupMenu : public Popup {
 	Timer *submenu_timer = nullptr;
 	List<Rect2> autohide_areas;
 	Vector<Item> items;
-	MouseButton initial_button_mask = MouseButton::NONE;
+	BitField<MouseButtonMask> initial_button_mask;
 	bool during_grabbed_click = false;
 	int mouse_over = -1;
 	int submenu_over = -1;
diff --git a/scene/gui/spin_box.cpp b/scene/gui/spin_box.cpp
index 29458ea16c..dfc03c666b 100644
--- a/scene/gui/spin_box.cpp
+++ b/scene/gui/spin_box.cpp
@@ -176,7 +176,7 @@ void SpinBox::gui_input(const Ref<InputEvent> &p_event) {
 
 	Ref<InputEventMouseMotion> mm = p_event;
 
-	if (mm.is_valid() && (mm->get_button_mask() & MouseButton::MASK_LEFT) != MouseButton::NONE) {
+	if (mm.is_valid() && (mm->get_button_mask().has_flag(MouseButtonMask::LEFT))) {
 		if (drag.enabled) {
 			drag.diff_y += mm->get_relative().y;
 			double diff_y = -0.01 * Math::pow(ABS(drag.diff_y), 1.8) * SIGN(drag.diff_y);
diff --git a/scene/gui/text_edit.cpp b/scene/gui/text_edit.cpp
index 898c91a03c..108a533a74 100644
--- a/scene/gui/text_edit.cpp
+++ b/scene/gui/text_edit.cpp
@@ -1906,7 +1906,7 @@ void TextEdit::gui_input(const Ref<InputEvent> &p_gui_input) {
 			mpos.x = get_size().x - mpos.x;
 		}
 
-		if ((mm->get_button_mask() & MouseButton::MASK_LEFT) != MouseButton::NONE && get_viewport()->gui_get_drag_data() == Variant()) { // Ignore if dragging.
+		if (mm->get_button_mask().has_flag(MouseButtonMask::LEFT) && get_viewport()->gui_get_drag_data() == Variant()) { // Ignore if dragging.
 			_reset_caret_blink_timer();
 
 			if (draw_minimap && !dragging_selection) {
diff --git a/scene/gui/view_panner.cpp b/scene/gui/view_panner.cpp
index 9a0c93a1df..e8d54e6937 100644
--- a/scene/gui/view_panner.cpp
+++ b/scene/gui/view_panner.cpp
@@ -114,7 +114,7 @@ bool ViewPanner::gui_input(const Ref<InputEvent> &p_event, Rect2 p_canvas_rect)
 	if (k.is_valid()) {
 		if (pan_view_shortcut.is_valid() && pan_view_shortcut->matches_event(k)) {
 			pan_key_pressed = k->is_pressed();
-			if (simple_panning_enabled || (Input::get_singleton()->get_mouse_button_mask() & MouseButton::LEFT) != MouseButton::NONE) {
+			if (simple_panning_enabled || Input::get_singleton()->get_mouse_button_mask().has_flag(MouseButtonMask::LEFT)) {
 				is_dragging = pan_key_pressed;
 			}
 			return true;
diff --git a/scene/main/viewport.cpp b/scene/main/viewport.cpp
index 1287f69bef..7ca1f9d3ec 100644
--- a/scene/main/viewport.cpp
+++ b/scene/main/viewport.cpp
@@ -603,9 +603,9 @@ void Viewport::_process_picking() {
 			physics_last_mouse_state.meta = mb->is_meta_pressed();
 
 			if (mb->is_pressed()) {
-				physics_last_mouse_state.mouse_mask |= mouse_button_to_mask(mb->get_button_index());
+				physics_last_mouse_state.mouse_mask.set_flag(mouse_button_to_mask(mb->get_button_index()));
 			} else {
-				physics_last_mouse_state.mouse_mask &= ~mouse_button_to_mask(mb->get_button_index());
+				physics_last_mouse_state.mouse_mask.clear_flag(mouse_button_to_mask(mb->get_button_index()));
 
 				// If touch mouse raised, assume we don't know last mouse pos until new events come
 				if (mb->get_device() == InputEvent::DEVICE_ID_TOUCH_MOUSE) {
@@ -1496,19 +1496,20 @@ void Viewport::_gui_input_event(Ref<InputEvent> p_event) {
 		Point2 mpos = mb->get_position();
 		if (mb->is_pressed()) {
 			Size2 pos = mpos;
-			if (gui.mouse_focus_mask != MouseButton::NONE) {
+			if (!gui.mouse_focus_mask.is_empty()) {
 				// Do not steal mouse focus and stuff while a focus mask exists.
-				gui.mouse_focus_mask |= mouse_button_to_mask(mb->get_button_index());
+				gui.mouse_focus_mask.set_flag(mouse_button_to_mask(mb->get_button_index()));
 			} else {
 				gui.mouse_focus = gui_find_control(pos);
 				gui.last_mouse_focus = gui.mouse_focus;
 
 				if (!gui.mouse_focus) {
-					gui.mouse_focus_mask = MouseButton::NONE;
+					gui.mouse_focus_mask.clear();
 					return;
 				}
 
-				gui.mouse_focus_mask = mouse_button_to_mask(mb->get_button_index());
+				gui.mouse_focus_mask.clear();
+				gui.mouse_focus_mask.set_flag(mouse_button_to_mask(mb->get_button_index()));
 
 				if (mb->get_button_index() == MouseButton::LEFT) {
 					gui.drag_accum = Vector2();
@@ -1578,7 +1579,7 @@ void Viewport::_gui_input_event(Ref<InputEvent> p_event) {
 				_perform_drop(gui.drag_mouse_over, gui.drag_mouse_over_pos);
 			}
 
-			gui.mouse_focus_mask &= ~mouse_button_to_mask(mb->get_button_index()); // Remove from mask.
+			gui.mouse_focus_mask.clear_flag(mouse_button_to_mask(mb->get_button_index())); // Remove from mask.
 
 			if (!gui.mouse_focus) {
 				// Release event is only sent if a mouse focus (previously pressed button) exists.
@@ -1597,7 +1598,7 @@ void Viewport::_gui_input_event(Ref<InputEvent> p_event) {
 			// Disable mouse focus if needed before calling input,
 			// this makes popups on mouse press event work better,
 			// as the release will never be received otherwise.
-			if (gui.mouse_focus_mask == MouseButton::NONE) {
+			if (gui.mouse_focus_mask.is_empty()) {
 				gui.mouse_focus = nullptr;
 				gui.forced_mouse_focus = false;
 			}
@@ -1619,7 +1620,7 @@ void Viewport::_gui_input_event(Ref<InputEvent> p_event) {
 		Point2 mpos = mm->get_position();
 
 		// Drag & drop.
-		if (!gui.drag_attempted && gui.mouse_focus && (mm->get_button_mask() & MouseButton::MASK_LEFT) != MouseButton::NONE) {
+		if (!gui.drag_attempted && gui.mouse_focus && (mm->get_button_mask().has_flag(MouseButtonMask::LEFT))) {
 			gui.drag_accum += mm->get_relative();
 			float len = gui.drag_accum.length();
 			if (len > 10) {
@@ -1633,7 +1634,7 @@ void Viewport::_gui_input_event(Ref<InputEvent> p_event) {
 							if (gui.drag_data.get_type() != Variant::NIL) {
 								gui.mouse_focus = nullptr;
 								gui.forced_mouse_focus = false;
-								gui.mouse_focus_mask = MouseButton::NONE;
+								gui.mouse_focus_mask.clear();
 								break;
 							} else {
 								Control *drag_preview = _gui_get_drag_preview();
@@ -1701,7 +1702,7 @@ void Viewport::_gui_input_event(Ref<InputEvent> p_event) {
 			mm->set_velocity(velocity);
 			mm->set_relative(rel);
 
-			if (mm->get_button_mask() == MouseButton::NONE) {
+			if (mm->get_button_mask().is_empty()) {
 				// Nothing pressed.
 
 				bool is_tooltip_shown = false;
@@ -1744,7 +1745,7 @@ void Viewport::_gui_input_event(Ref<InputEvent> p_event) {
 				Control *c = over;
 				Vector2 cpos = pos;
 				while (c) {
-					if (gui.mouse_focus_mask != MouseButton::NONE || c->has_point(cpos)) {
+					if (!gui.mouse_focus_mask.is_empty() || c->has_point(cpos)) {
 						cursor_shape = c->get_cursor_shape(cpos);
 					} else {
 						cursor_shape = Control::CURSOR_ARROW;
@@ -2103,7 +2104,7 @@ void Viewport::_gui_cleanup_internal_state(Ref<InputEvent> p_event) {
 	Ref<InputEventMouseButton> mb = p_event;
 	if (mb.is_valid()) {
 		if (!mb->is_pressed()) {
-			gui.mouse_focus_mask &= ~mouse_button_to_mask(mb->get_button_index()); // Remove from mask.
+			gui.mouse_focus_mask.clear_flag(mouse_button_to_mask(mb->get_button_index())); // Remove from mask.
 		}
 	}
 }
@@ -2194,7 +2195,7 @@ void Viewport::_gui_remove_control(Control *p_control) {
 	if (gui.mouse_focus == p_control) {
 		gui.mouse_focus = nullptr;
 		gui.forced_mouse_focus = false;
-		gui.mouse_focus_mask = MouseButton::NONE;
+		gui.mouse_focus_mask.clear();
 	}
 	if (gui.last_mouse_focus == p_control) {
 		gui.last_mouse_focus = nullptr;
@@ -2263,10 +2264,10 @@ void Viewport::_drop_mouse_over() {
 
 void Viewport::_drop_mouse_focus() {
 	Control *c = gui.mouse_focus;
-	MouseButton mask = gui.mouse_focus_mask;
+	BitField<MouseButtonMask> mask = gui.mouse_focus_mask;
 	gui.mouse_focus = nullptr;
 	gui.forced_mouse_focus = false;
-	gui.mouse_focus_mask = MouseButton::NONE;
+	gui.mouse_focus_mask.clear();
 
 	for (int i = 0; i < 3; i++) {
 		if ((int)mask & (1 << i)) {
@@ -2374,7 +2375,7 @@ void Viewport::_post_gui_grab_click_focus() {
 			return;
 		}
 
-		MouseButton mask = gui.mouse_focus_mask;
+		BitField<MouseButtonMask> mask = gui.mouse_focus_mask;
 		Point2 click = gui.mouse_focus->get_global_transform_with_canvas().affine_inverse().xform(gui.last_mouse_pos);
 
 		for (int i = 0; i < 3; i++) {
@@ -3239,7 +3240,7 @@ void Viewport::pass_mouse_focus_to(Viewport *p_viewport, Control *p_control) {
 
 		gui.mouse_focus = nullptr;
 		gui.forced_mouse_focus = false;
-		gui.mouse_focus_mask = MouseButton::NONE;
+		gui.mouse_focus_mask.clear();
 	}
 }
 
diff --git a/scene/main/viewport.h b/scene/main/viewport.h
index ca6f3163df..9f182682d7 100644
--- a/scene/main/viewport.h
+++ b/scene/main/viewport.h
@@ -259,7 +259,7 @@ private:
 		bool control = false;
 		bool shift = false;
 		bool meta = false;
-		MouseButton mouse_mask = MouseButton::NONE;
+		BitField<MouseButtonMask> mouse_mask;
 
 	} physics_last_mouse_state;
 
@@ -358,7 +358,7 @@ private:
 		Control *mouse_focus = nullptr;
 		Control *last_mouse_focus = nullptr;
 		Control *mouse_click_grabber = nullptr;
-		MouseButton mouse_focus_mask = MouseButton::NONE;
+		BitField<MouseButtonMask> mouse_focus_mask;
 		Control *key_focus = nullptr;
 		Control *mouse_over = nullptr;
 		Control *drag_mouse_over = nullptr;