Code cleanup of the widget's code.

Improved function names, descriptions and ordering of the functions.
Also added override markers for C++11.

src/addon/manager_ui.cpp

@@ -40,6 +40,7 @@
 #include "log.hpp"
 #include "marked-up_text.hpp"
 #include "wml_separators.hpp"
+#include "wml_exception.hpp"
 
 #include <boost/scoped_ptr.hpp>
 #include <boost/foreach.hpp>

src/editor/editor_controller.cpp

@@ -30,6 +30,7 @@
 #include "gui/dialogs/message.hpp"
 #include "gui/dialogs/transient_message.hpp"
 #include "gui/widgets/window.hpp"
+#include "wml_exception.hpp"
 
 #include "../clipboard.hpp"
 #include "../game_preferences.hpp"

src/game.cpp

@@ -35,6 +35,7 @@
 #include "serialization/parser.hpp"
 #include "serialization/validator.hpp"
 #include "version.hpp"
+#include "wml_exception.hpp"
 
 #include <cerrno>
 #include <clocale>

src/gui/auxiliary/canvas.hpp

@@ -104,10 +104,10 @@ public:
 
 	/***** ***** ***** setters / getters for members ***** ****** *****/
 
-	void set_width(const unsigned width) { w_ = width; set_dirty(); }
+	void set_width(const unsigned width) { w_ = width; set_dirty(true); }
 	unsigned get_width() const { return w_; }
 
-	void set_height(const unsigned height) { h_ = height; set_dirty(); }
+	void set_height(const unsigned height) { h_ = height; set_dirty(true); }
 	unsigned get_height() const { return h_; }
 
 	surface& surf() { return canvas_; }
@@ -115,7 +115,7 @@ public:
 	void set_variable(const std::string& key, const variant& value)
 	{
 		variables_.add(key, value);
-		set_dirty();
+		set_dirty(true);
 	}
 
 private:

src/gui/auxiliary/event/handler.cpp

@@ -430,7 +430,7 @@ void thandler::disconnect(tdispatcher* dispatcher)
 
 	/***** Set proper state for the other dispatchers. *****/
 	FOREACH(AUTO dispatcher, dispatchers_) {
-		dynamic_cast<twidget&>(*dispatcher).set_dirty();
+		dynamic_cast<twidget&>(*dispatcher).set_dirty(true);
 	}
 
 	activate();
@@ -480,7 +480,7 @@ void thandler::draw(const bool force)
 			 * causes black borders around the window. So there's the choice
 			 * between two evils.
 			 */
-			dynamic_cast<twidget&>(*dispatcher).set_dirty();
+			dynamic_cast<twidget&>(*dispatcher).set_dirty(true);
 		} else {
 			first = false;
 		}

src/gui/auxiliary/find_widget.tpp

@@ -16,7 +16,10 @@
 #ifndef GUI_AUXILIARY_FIND_WIDGET_TPP_INCLUDED
 #define GUI_AUXILIARY_FIND_WIDGET_TPP_INCLUDED
 
+#include "gui/widgets/helper.hpp"
 #include "gui/widgets/widget.hpp"
+#include "utils/const_clone.tpp"
+#include "wml_exception.hpp"
 
 namespace gui2 {
 

src/gui/auxiliary/window_builder.cpp

@@ -45,6 +45,7 @@
 #include "gui/widgets/window.hpp"
 #include "formula_string_utils.hpp"
 #include "utils/foreach.tpp"
+#include "wml_exception.hpp"
 
 #include <boost/bind.hpp>
 

src/gui/auxiliary/window_builder/control.cpp

@@ -22,6 +22,7 @@
 #include "gettext.hpp"
 #include "gui/auxiliary/log.hpp"
 #include "gui/widgets/control.hpp"
+#include "wml_exception.hpp"
 
 namespace gui2 {
 
@@ -63,7 +64,7 @@ void tbuilder_control::init_control(tcontrol* control) const
 	control->set_use_tooltip_on_label_overflow(use_tooltip_on_label_overflow);
 #ifndef LOW_MEM
 	control->set_debug_border_mode(debug_border_mode);
-	control->set_debug_border_color(debug_border_color);
+	control->set_debug_border_colour(debug_border_color);
 #endif
 }
 

src/gui/auxiliary/window_builder/instance.hpp

@@ -18,6 +18,8 @@
 
 #include "gui/auxiliary/window_builder.hpp"
 
+#include "config.hpp"
+
 namespace gui2 {
 
 namespace implementation {

src/gui/auxiliary/window_builder/multi_page.hpp

@@ -22,6 +22,8 @@
 #include <map>
 #include <vector>
 
+typedef std::map<std::string, t_string> string_map;
+
 namespace gui2 {
 
 namespace implementation {

src/gui/auxiliary/window_builder/pane.cpp

@@ -17,8 +17,10 @@
 
 #include "gui/auxiliary/window_builder/pane.hpp"
 
+#include "config.hpp"
 #include "gettext.hpp"
 #include "gui/widgets/pane.hpp"
+#include "wml_exception.hpp"
 
 namespace gui2 {
 

src/gui/auxiliary/window_builder/viewport.cpp

@@ -17,6 +17,7 @@
 
 #include "gui/auxiliary/window_builder/viewport.hpp"
 
+#include "config.hpp"
 #include "gui/widgets/viewport.hpp"
 
 namespace gui2 {

src/gui/dialogs/addon_list.cpp

@@ -75,25 +75,25 @@ REGISTER_DIALOG(addon_list)
 void taddon_list::collapse(tgrid& grid)
 {
 	find_widget<ttoggle_button>(&grid, "expand", false)
-			.set_visible(twidget::VISIBLE);
+			.set_visible(twidget::tvisible::visible);
 
 	find_widget<ttoggle_button>(&grid, "collapse", false)
-			.set_visible(twidget::INVISIBLE);
+			.set_visible(twidget::tvisible::invisible);
 
 	find_widget<tlabel>(&grid, "description", false)
-			.set_visible(twidget::INVISIBLE);
+			.set_visible(twidget::tvisible::invisible);
 }
 
 void taddon_list::expand(tgrid& grid)
 {
 	find_widget<ttoggle_button>(&grid, "expand", false)
-			.set_visible(twidget::HIDDEN);
+			.set_visible(twidget::tvisible::hidden);
 
 	find_widget<ttoggle_button>(&grid, "collapse", false)
-			.set_visible(twidget::VISIBLE);
+			.set_visible(twidget::tvisible::visible);
 
 	find_widget<tlabel>(&grid, "description", false)
-			.set_visible(twidget::VISIBLE);
+			.set_visible(twidget::tvisible::visible);
 }
 
 void taddon_list::pre_show(CVideo& /*video*/, twindow& window)
@@ -291,7 +291,7 @@ void taddon_list::create_campaign(tpane& pane, const config& campaign)
 					, false);
 
 			if(collapse) {
-				collapse->set_visible(twidget::INVISIBLE);
+				collapse->set_visible(twidget::tvisible::invisible);
 				collapse->set_callback_state_change(boost::bind(
 						  &taddon_list::collapse
 						, this
@@ -304,7 +304,7 @@ void taddon_list::create_campaign(tpane& pane, const config& campaign)
 							, boost::ref(*grid)));
 
 				find_widget<tlabel>(grid, "description", false)
-						.set_visible(twidget::INVISIBLE);
+						.set_visible(twidget::tvisible::invisible);
 			}
 
 }

src/gui/dialogs/campaign_selection.cpp

@@ -185,7 +185,7 @@ void tcampaign_selection::pre_show(CVideo& /*video*/, twindow& window)
 		if(ttree_view* tree = find_widget<ttree_view>(
 				&window, "campaign_tree", false, false)) {
 
-			tree->set_visible(twidget::INVISIBLE);
+			tree->set_visible(twidget::tvisible::invisible);
 		}
 
 		/***** Setup campaign list. *****/
@@ -226,7 +226,7 @@ void tcampaign_selection::pre_show(CVideo& /*video*/, twindow& window)
 
 			twidget* widget = grid->find("victory", false);
 			if (widget && !campaign["completed"].to_bool()) {
-				widget->set_visible(twidget::HIDDEN);
+				widget->set_visible(twidget::tvisible::hidden);
 			}
 
 			/*** Add detail item ***/

src/gui/dialogs/debug_clock.cpp

@@ -163,7 +163,7 @@ void tdebug_clock::update_time(const bool force)
 			canvas.set_variable("minute", variant(minute_stamp));
 			canvas.set_variable("second", variant(second_stamp));
 		}
-		clock_->set_dirty();
+		clock_->set_dirty(true);
 	}
 
 	const std::map<std::string, std::string> tags;

src/gui/dialogs/game_load.cpp

@@ -234,9 +234,9 @@ void tgame_load::display_savegame(twindow& window)
 			find_widget<twidget>(&window, "preview_pane", false);
 
 	if(selected_row == -1) {
-		preview_pane.set_visible(twidget::HIDDEN);
+		preview_pane.set_visible(twidget::tvisible::hidden);
 	} else {
-		preview_pane.set_visible(twidget::VISIBLE);
+		preview_pane.set_visible(twidget::tvisible::visible);
 
 		savegame::save_info& game = games_[selected_row];
 		filename_ = game.name();

src/gui/dialogs/lobby_main.cpp

@@ -108,10 +108,10 @@ void tsub_player_list::init(gui2::twindow &w, const std::string &id)
 void tsub_player_list::show_toggle_callback(gui2::twidget* /*widget*/)
 {
 	if (show_toggle->get_value()) {
-		list->set_visible(twidget::INVISIBLE);
+		list->set_visible(twidget::tvisible::invisible);
 		show_toggle->set_icon_name("lobby/group-folded.png");
 	} else {
-		list->set_visible(twidget::VISIBLE);
+		list->set_visible(twidget::tvisible::visible);
 		show_toggle->set_icon_name("lobby/group-expanded.png");
 	}
 }
@@ -130,13 +130,13 @@ void tsub_player_list::auto_hide()
 		 */
 		assert(label);
 		tree_label->set_label(label->label() + " (0)");
-//			tree_label->set_visible(twidget::INVISIBLE);
+//			tree_label->set_visible(twidget::tvisible::invisible);
 	} else {
 		assert(label);
 		std::stringstream ss;
 		ss << label->label() << " (" << tree->size() << ")";
 		tree_label->set_label(ss.str());
-//			tree_label->set_visible(twidget::VISIBLE);
+//			tree_label->set_visible(twidget::tvisible::visible);
 		}
 }
 
@@ -157,7 +157,7 @@ void tplayer_list::init(gui2::twindow &w)
 			, true);
 
 	find_widget<twidget>(&w, "old_player_list", false)
-			.set_visible(twidget::INVISIBLE);
+			.set_visible(twidget::tvisible::invisible);
 
 	/**
 	 * @todo This is a hack to fold the items.
@@ -519,7 +519,9 @@ void set_visible_if_exists(tgrid* grid, const char* id, bool visible)
 {
 	twidget* w = grid->find(id, false);
 	if (w) {
-		w->set_visible(visible ? twidget::VISIBLE : twidget::INVISIBLE);
+		w->set_visible(visible
+				? twidget::tvisible::visible
+				: twidget::tvisible::invisible);
 	}
 }
 
@@ -1147,7 +1149,7 @@ void tlobby_main::increment_waiting_whsipers(const std::string& name)
 			//label.set_use_markup(true);
 			//label.set_label(colorize("<" + t->name + ">", "red"));
 			find_widget<timage>(grid, "pending_messages", false)
-					.set_visible(twidget::VISIBLE);
+					.set_visible(twidget::tvisible::visible);
 		}
 	}
 }
@@ -1166,7 +1168,7 @@ void tlobby_main::increment_waiting_messages(const std::string& room)
 			//label.set_use_markup(true);
 			//label.set_label(colorize(t->name, "red"));
 			find_widget<timage>(grid, "pending_messages", false)
-					.set_visible(twidget::VISIBLE);
+					.set_visible(twidget::tvisible::visible);
 		}
 	}
 }
@@ -1257,7 +1259,7 @@ void tlobby_main::active_window_changed()
 	//tlabel& label = grid->get_widget<tlabel>("room", false);
 	//label.set_label(expected_label);
 	find_widget<timage>(grid, "pending_messages", false)
-			.set_visible(twidget::HIDDEN);
+			.set_visible(twidget::tvisible::hidden);
 	t.pending_messages = 0;
 
 	find_widget<tbutton>(window_, "close_window", false)

src/gui/dialogs/lobby_player_info.cpp

@@ -112,7 +112,7 @@ void tlobby_player_info::pre_show(CVideo& /*video*/, twindow& window)
 
 	if (!preferences::is_authenticated()) {
 		twidget* aw = window.find("admin", false);
-		aw->set_visible(twidget::INVISIBLE);
+		aw->set_visible(twidget::tvisible::invisible);
 	}
 }
 

src/gui/dialogs/message.cpp

@@ -113,7 +113,7 @@ void tmessage::set_button_caption(const tbutton_id button,
 }
 
 void tmessage::set_button_visible(const tbutton_id button,
-		const twidget::tvisible visible)
+		const twidget::tvisible::scoped_enum visible)
 {
 	buttons_[button].visible = visible;
 	if(buttons_[button].button) {
@@ -133,7 +133,7 @@ void tmessage::set_button_retval(const tbutton_id button,
 tmessage::tbutton_status::tbutton_status()
 	: button(NULL)
 	, caption()
-	, visible(twidget::INVISIBLE)
+	, visible(twidget::tvisible::invisible)
 	, retval(twindow::NONE)
 {
 }
@@ -159,23 +159,23 @@ int show_message(CVideo& video, const std::string& title,
 		case tmessage::auto_close :
 			break;
 		case tmessage::ok_button :
-			dlg.set_button_visible(tmessage::ok, twidget::VISIBLE);
+			dlg.set_button_visible(tmessage::ok, twidget::tvisible::visible);
 			dlg.set_button_caption(tmessage::ok, _("OK"));
 			break;
 		case tmessage::close_button :
-			dlg.set_button_visible(tmessage::ok, twidget::VISIBLE);
+			dlg.set_button_visible(tmessage::ok, twidget::tvisible::visible);
 			break;
 		case tmessage::ok_cancel_buttons :
-			dlg.set_button_visible(tmessage::ok, twidget::VISIBLE);
+			dlg.set_button_visible(tmessage::ok, twidget::tvisible::visible);
 			dlg.set_button_caption(tmessage::ok, _("OK"));
 			/* FALL DOWN */
 		case tmessage::cancel_button :
-			dlg.set_button_visible(tmessage::cancel, twidget::VISIBLE);
+			dlg.set_button_visible(tmessage::cancel, twidget::tvisible::visible);
 			break;
 		case tmessage::yes_no_buttons :
-			dlg.set_button_visible(tmessage::ok, twidget::VISIBLE);
+			dlg.set_button_visible(tmessage::ok, twidget::tvisible::visible);
 			dlg.set_button_caption(tmessage::ok, _("Yes"));
-			dlg.set_button_visible(tmessage::cancel, twidget::VISIBLE);
+			dlg.set_button_visible(tmessage::cancel, twidget::tvisible::visible);
 			dlg.set_button_caption(tmessage::cancel, _("No"));
 			break;
 	}

src/gui/dialogs/message.hpp

@@ -70,7 +70,7 @@ public:
 			const std::string& caption);
 
 	void set_button_visible(const tbutton_id button,
-			const twidget::tvisible visible);
+			const twidget::tvisible::scoped_enum visible);
 
 	void set_button_retval(const tbutton_id button,
 			const int retval);
@@ -118,7 +118,7 @@ private:
 
 		tbutton* button;
 		std::string caption;
-		twidget::tvisible visible;
+		twidget::tvisible::scoped_enum visible;
 		int retval;
 	};
 

src/gui/dialogs/simple_item_selector.cpp

@@ -108,7 +108,7 @@ void tsimple_item_selector::pre_show(CVideo& /*video*/, twindow& window)
 	}
 
 	if(single_button_) {
-		button_cancel.set_visible(gui2::twidget::INVISIBLE);
+		button_cancel.set_visible(gui2::twidget::tvisible::invisible);
 	}
 }
 

src/gui/dialogs/title_screen.cpp

@@ -151,7 +151,7 @@ static void animate_logo(
 	 * this possible problem. Of course this is expensive but the logo is
 	 * animated once so the cost is only once.
 	 */
-	window.set_dirty();
+	window.set_dirty(true);
 
 	if(percentage == 100) {
 		remove_timer(timer_id);
@@ -385,8 +385,8 @@ void ttitle_screen::pre_show(CVideo& video, twindow& window)
 	/***** Set the clock button. *****/
 	tbutton& clock = find_widget<tbutton>(&window, "clock", false);
 	clock.set_visible(show_debug_clock_button
-			? twidget::VISIBLE
+			? twidget::tvisible::visible
-			: twidget::INVISIBLE);
+			: twidget::tvisible::invisible);
 
 	connect_signal_mouse_left_click(
 			  clock

src/gui/dialogs/wml_message.cpp

@@ -90,8 +90,8 @@ void twml_message_::pre_show(CVideo& /*video*/, twindow& window)
 		window.set_click_dismiss(false);
 		window.set_escape_disabled(true);
 	} else {
-		caption.set_visible(twidget::INVISIBLE);
+		caption.set_visible(twidget::tvisible::invisible);
-		input.set_visible(twidget::INVISIBLE);
+		input.set_visible(twidget::tvisible::invisible);
 	}
 
 	// Find the option list related fields.
@@ -138,7 +138,7 @@ void twml_message_::pre_show(CVideo& /*video*/, twindow& window)
 			// click_dismiss has been disabled due to the input.
 		}
 	} else {
-		options.set_visible(twidget::INVISIBLE);
+		options.set_visible(twidget::tvisible::invisible);
 	}
 	window.set_click_dismiss(!has_input_ && option_list_.empty());
 }

src/gui/widgets/container.cpp

@@ -25,12 +25,12 @@
 
 namespace gui2 {
 
-void tcontainer_::layout_init(const bool full_initialization)
+void tcontainer_::layout_initialise(const bool full_initialisation)
 {
 	// Inherited.
-	tcontrol::layout_init(full_initialization);
+	tcontrol::layout_initialise(full_initialisation);
 
-	grid_.layout_init(full_initialization);
+	grid_.layout_initialise(full_initialisation);
 }
 
 void tcontainer_::reduce_width(const unsigned maximum_width)
@@ -108,18 +108,18 @@ void tcontainer_::set_origin(const tpoint& origin)
 	grid_.set_origin(client_position);
 }
 
-void tcontainer_::set_visible_area(const SDL_Rect& area)
+void tcontainer_::set_visible_rectangle(const SDL_Rect& rectangle)
 {
 	// Inherited.
-	twidget::set_visible_area(area);
+	twidget::set_visible_rectangle(rectangle);
 
-	grid_.set_visible_area(area);
+	grid_.set_visible_rectangle(rectangle);
 }
 
 void tcontainer_::impl_draw_children(surface& frame_buffer)
 {
-	assert(get_visible() == twidget::VISIBLE
+	assert(get_visible() == twidget::tvisible::visible
-			&& grid_.get_visible() == twidget::VISIBLE);
+			&& grid_.get_visible() == twidget::tvisible::visible);
 
 	grid_.draw_children(frame_buffer);
 }
@@ -129,8 +129,8 @@ void tcontainer_::impl_draw_children(
 		, int x_offset
 		, int y_offset)
 {
-	assert(get_visible() == twidget::VISIBLE
+	assert(get_visible() == twidget::tvisible::visible
-			&& grid_.get_visible() == twidget::VISIBLE);
+			&& grid_.get_visible() == twidget::tvisible::visible);
 
 	grid_.draw_children(frame_buffer, x_offset, y_offset);
 }
@@ -157,7 +157,7 @@ void tcontainer_::set_active(const bool active)
 		return;
 	}
 
-	set_dirty();
+	set_dirty(true);
 
 	set_self_active(active);
 }

src/gui/widgets/container.hpp

@@ -45,12 +45,12 @@ public:
 	 *
 	 * The client area is the area available for widgets.
 	 */
-	virtual SDL_Rect get_client_rect() const { return get_rect(); }
+	virtual SDL_Rect get_client_rect() const { return get_rectangle(); }
 
 	/***** ***** ***** ***** layout functions ***** ***** ***** *****/
 
-	/** Inherited from tcontrol. */
+	/** See @ref twidget::layout_initialise. */
-	void layout_init(const bool full_initialization);
+	virtual void layout_initialise(const bool full_initialisation) OVERRIDE;
 
 	/**
 	 * Tries to reduce the width of a container.
@@ -102,8 +102,8 @@ public:
 	/** Inherited from twidget. */
 	void set_origin(const tpoint& origin);
 
-	/** Inherited from twidget. */
+	/** See @ref twidget::set_visible_rectangle. */
-	void set_visible_area(const SDL_Rect& area);
+	virtual void set_visible_rectangle(const SDL_Rect& rectangle) OVERRIDE;
 
 	/** Inherited from twidget. */
 	void impl_draw_children(surface& frame_buffer);

src/gui/widgets/control.cpp

@@ -152,7 +152,7 @@ void tcontrol::set_members(const string_map& data)
 
 bool tcontrol::disable_click_dismiss() const
 {
-	return get_visible() == twidget::VISIBLE && get_active();
+	return get_visible() == twidget::tvisible::visible && get_active();
 }
 
 iterator::twalker_* tcontrol::create_walker()
@@ -195,12 +195,12 @@ unsigned tcontrol::get_characters_per_line() const
 	return 0;
 }
 
-void tcontrol::layout_init(const bool full_initialization)
+void tcontrol::layout_initialise(const bool full_initialisation)
 {
 	// Inherited.
-	twidget::layout_init(full_initialization);
+	twidget::layout_initialise(full_initialisation);
 
-	if(full_initialization) {
+	if(full_initialisation) {
 		shrunken_ = false;
 	}
 }
@@ -310,7 +310,7 @@ void tcontrol::set_label(const t_string& label)
 	label_ = label;
 	set_layout_size(tpoint(0, 0));
 	update_canvas();
-	set_dirty();
+	set_dirty(true);
 }
 
 void tcontrol::set_use_markup(bool use_markup)
@@ -321,7 +321,7 @@ void tcontrol::set_use_markup(bool use_markup)
 
 	use_markup_ = use_markup;
 	update_canvas();
-	set_dirty();
+	set_dirty(true);
 }
 
 void tcontrol::set_text_alignment(const PangoAlignment text_alignment)
@@ -332,7 +332,7 @@ void tcontrol::set_text_alignment(const PangoAlignment text_alignment)
 
 	text_alignment_ = text_alignment;
 	update_canvas();
-	set_dirty();
+	set_dirty(true);
 }
 
 void tcontrol::update_canvas()
@@ -376,10 +376,10 @@ void tcontrol::impl_draw_background(surface& frame_buffer)
 {
 	DBG_GUI_D << LOG_HEADER
 			<< " label '" << debug_truncate(label_)
-			<< "' size " << get_rect()
+			<< "' size " << get_rectangle()
 			<< ".\n";
 
-	canvas(get_state()).blit(frame_buffer, get_rect());
+	canvas(get_state()).blit(frame_buffer, get_rectangle());
 }
 
 void tcontrol::impl_draw_background(
@@ -389,7 +389,7 @@ void tcontrol::impl_draw_background(
 {
 	DBG_GUI_D << LOG_HEADER
 			<< " label '" << debug_truncate(label_)
-			<< "' size " << get_rect()
+			<< "' size " << get_rectangle()
 			<< ".\n";
 
 	canvas(get_state()).blit(

src/gui/widgets/control.hpp

@@ -20,6 +20,8 @@
 #include "gui/widgets/widget.hpp"
 #include "../../text.hpp"
 
+typedef std::map<std::string, t_string> string_map;
+
 namespace gui2 {
 
 namespace implementation {
@@ -140,10 +142,13 @@ public:
 	 */
 	virtual unsigned get_characters_per_line() const;
 
-	/** Inherited from twidget. */
+	/**
-	/** @todo Also handle the tooltip state if shrunken_ &&
+	 * See @ref twidget::layout_initialise.
-	 * use_tooltip_on_label_overflow_. */
+	 *
-	void layout_init(const bool full_initialization);
+	 * @todo Also handle the tooltip state.
+	 * Handle if shrunken_ && use_tooltip_on_label_overflow_.
+	 */
+	virtual void layout_initialise(const bool full_initialisation) OVERRIDE;
 
 	/** Inherited from twidget. */
 	void request_reduce_width(const unsigned maximum_width);

src/gui/widgets/debug.cpp

@@ -331,7 +331,7 @@ void tdebug_layout_graph::widget_generate_state_info(
 		<< "drawing action=" << control->get_drawing_action() << '\n'
 		<< "</td></tr>\n"
 		<< "<tr><td>\n"
-		<< "clip rect=" << control->clip_rect_ << '\n'
+		<< "clip rect=" << control->clipping_rectangle_ << '\n'
 		<< "</td></tr>\n"
 		<< "<tr><td>\n"
 		<< "use tooltip on label overflow="

src/gui/widgets/generator.cpp

@@ -19,6 +19,7 @@
 
 #include "gui/widgets/window.hpp"
 #include "utils/foreach.tpp"
+#include "wml_exception.hpp"
 
 namespace gui2 {
 
@@ -120,7 +121,9 @@ tpoint thorizontal_list::calculate_best_size() const
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		const tgrid& grid = item(i);
-		if(grid.get_visible() == twidget::INVISIBLE || !get_item_shown(i)) {
+		if(grid.get_visible() == twidget::tvisible::invisible
+				|| !get_item_shown(i)) {
+
 			continue;
 		}
 
@@ -150,7 +153,9 @@ void thorizontal_list::place(const tpoint& origin, const tpoint& size)
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		tgrid& grid = item(i);
-		if(grid.get_visible() == twidget::INVISIBLE || !get_item_shown(i)) {
+		if(grid.get_visible() == twidget::tvisible::invisible
+				|| !get_item_shown(i)) {
+
 			continue;
 		}
 
@@ -173,7 +178,9 @@ void thorizontal_list::set_origin(const tpoint& origin)
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		tgrid& grid = item(i);
-		if(grid.get_visible() == twidget::INVISIBLE || !get_item_shown(i)) {
+		if(grid.get_visible() == twidget::tvisible::invisible
+				|| !get_item_shown(i)) {
+
 			continue;
 		}
 
@@ -182,7 +189,7 @@ void thorizontal_list::set_origin(const tpoint& origin)
 	}
 }
 
-void thorizontal_list::set_visible_area(const SDL_Rect& area)
+void thorizontal_list::set_visible_rectangle(const SDL_Rect& rectangle)
 {
 	/*
 	 * Note for most implementations this function could work only for the
@@ -193,7 +200,7 @@ void thorizontal_list::set_visible_area(const SDL_Rect& area)
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		tgrid& grid = item(i);
-		grid.set_visible_area(area);
+		grid.set_visible_rectangle(rectangle);
 	}
 }
 
@@ -205,7 +212,9 @@ twidget* thorizontal_list::find_at(
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		tgrid& grid = item(i);
-		if(grid.get_visible() == twidget::INVISIBLE || !get_item_shown(i)) {
+		if(grid.get_visible() == twidget::tvisible::invisible
+				|| !get_item_shown(i)) {
+
 			continue;
 		}
 
@@ -227,7 +236,9 @@ const twidget* thorizontal_list::find_at(const tpoint& coordinate,
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		const tgrid& grid = item(i);
-		if(grid.get_visible() == twidget::INVISIBLE || !get_item_shown(i)) {
+		if(grid.get_visible() == twidget::tvisible::invisible
+				|| !get_item_shown(i)) {
+
 			continue;
 		}
 
@@ -275,7 +286,7 @@ void thorizontal_list::handle_key_right_arrow(
 
 	for(size_t i = get_selected_item() + 1; i < get_item_count(); ++i) {
 
-		if(item(i).get_visible() == twidget::INVISIBLE
+		if(item(i).get_visible() == twidget::tvisible::invisible
 				|| !get_item_shown(i)) {
 
 			continue;
@@ -313,7 +324,9 @@ tpoint tvertical_list::calculate_best_size() const
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		const tgrid& grid = item(i);
-		if(grid.get_visible() == twidget::INVISIBLE || !get_item_shown(i)) {
+		if(grid.get_visible() == twidget::tvisible::invisible
+				|| !get_item_shown(i)) {
+
 			continue;
 		}
 
@@ -343,7 +356,9 @@ void tvertical_list::place(const tpoint& origin, const tpoint& size)
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		tgrid& grid = item(i);
-		if(grid.get_visible() == twidget::INVISIBLE || !get_item_shown(i)) {
+		if(grid.get_visible() == twidget::tvisible::invisible
+				|| !get_item_shown(i)) {
+
 			continue;
 		}
 
@@ -366,7 +381,9 @@ void tvertical_list::set_origin(const tpoint& origin)
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		tgrid& grid = item(i);
-		if(grid.get_visible() == twidget::INVISIBLE || !get_item_shown(i)) {
+		if(grid.get_visible() == twidget::tvisible::invisible
+				|| !get_item_shown(i)) {
+
 			continue;
 		}
 
@@ -375,7 +392,7 @@ void tvertical_list::set_origin(const tpoint& origin)
 	}
 }
 
-void tvertical_list::set_visible_area(const SDL_Rect& area)
+void tvertical_list::set_visible_rectangle(const SDL_Rect& rectangle)
 {
 	/*
 	 * Note for most implementations this function could work only for the
@@ -386,7 +403,7 @@ void tvertical_list::set_visible_area(const SDL_Rect& area)
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		tgrid& grid = item(i);
-		grid.set_visible_area(area);
+		grid.set_visible_rectangle(rectangle);
 	}
 }
 
@@ -398,7 +415,9 @@ twidget* tvertical_list::find_at(
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		tgrid& grid = item(i);
-		if(grid.get_visible() == twidget::INVISIBLE || !get_item_shown(i)) {
+		if(grid.get_visible() == twidget::tvisible::invisible
+				|| !get_item_shown(i)) {
+
 			continue;
 		}
 
@@ -421,7 +440,9 @@ const twidget* tvertical_list::find_at(const tpoint& coordinate,
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		const tgrid& grid = item(i);
-		if(grid.get_visible() == twidget::INVISIBLE || !get_item_shown(i)) {
+		if(grid.get_visible() == twidget::tvisible::invisible
+				|| !get_item_shown(i)) {
+
 			continue;
 		}
 
@@ -467,7 +488,7 @@ void tvertical_list::handle_key_down_arrow(SDLMod /*modifier*/, bool& handled)
 
 	for(size_t i = get_selected_item() + 1; i < get_item_count(); ++i) {
 
-		if(item(i).get_visible() == twidget::INVISIBLE
+		if(item(i).get_visible() == twidget::tvisible::invisible
 					|| !get_item_shown(i)) {
 
 			continue;
@@ -606,10 +627,10 @@ const twidget* tindependent::find(
 	return NULL;
 }
 
-void tindependent::set_visible_area(const SDL_Rect& area)
+void tindependent::set_visible_rectangle(const SDL_Rect& rectangle)
 {
 	/*
-	 * Set the visible area for every item.
+	 * Set the visible rectangle for every item.
 	 *
 	 * @todo evaluate whether setting it only for the visible item is better
 	 * and what the consequences are.
@@ -617,7 +638,7 @@ void tindependent::set_visible_area(const SDL_Rect& area)
 	for(size_t i = 0; i < get_item_count(); ++i) {
 
 		tgrid& grid = item(i);
-		grid.set_visible_area(area);
+		grid.set_visible_rectangle(rectangle);
 	}
 }
 

src/gui/widgets/generator.hpp

@@ -21,6 +21,8 @@
 
 #include <boost/intrusive_ptr.hpp>
 
+typedef std::map< std::string, t_string > string_map;
+
 namespace gui2 {
 
 struct tbuilder_grid;
@@ -236,8 +238,8 @@ public:
 	 * become pure virtuals.
 	 */
 
-	/** Inherited from twidget. */
+	/** See @ref twidget::layout_initialise. */
-	virtual void layout_init(const bool full_initialization) = 0;
+	virtual void layout_initialise(const bool full_initialisation) OVERRIDE = 0;
 
 	/** Inherited from twidget. */
 	virtual void request_reduce_width(const unsigned maximum_width) = 0;
@@ -254,8 +256,8 @@ public:
 	/** Inherited from twidget. */
 	virtual void set_origin(const tpoint& origin) = 0;
 
-	/** Inherited from twidget. */
+	/** See @ref twidget::set_visible_rectangle. */
-	void set_visible_area(const SDL_Rect& area) = 0;
+	virtual void set_visible_rectangle(const SDL_Rect& rectangle) OVERRIDE = 0;
 
 	/** Inherited from twidget. */
 	virtual void impl_draw_children(surface& frame_buffer) = 0;

src/gui/widgets/generator_private.hpp

@@ -218,11 +218,11 @@ struct thorizontal_list
 	void set_origin(const tpoint& origin);
 
 	/**
-	 * Sets the visible area of the generator.
+	 * Sets the visible rectangle of the generator.
 	 *
-	 * @param area                The visible area.
+	 * @param rectangle           The visible rectangle.
 	 */
-	void set_visible_area(const SDL_Rect& area);
+	void set_visible_rectangle(const SDL_Rect& rectangle);
 
 	/** Inherited from tgenerator_. */
 	twidget* find_at(const tpoint& coordinate, const bool must_be_active);
@@ -288,8 +288,8 @@ struct tvertical_list
 	/** See thorizontal_list::set_origin(). */
 	void set_origin(const tpoint& origin);
 
-	/** See thorizontal_list::set_visible_area(). */
+	/** See @ref thorizontal_list::set_visible_rectangle(). */
-	void set_visible_area(const SDL_Rect& area);
+	void set_visible_rectangle(const SDL_Rect& rectangle);
 
 	/** See thorizontal_list::find_at(). */
 	twidget* find_at(const tpoint& coordinate, const bool must_be_active);
@@ -364,8 +364,8 @@ struct tmatrix
 	void set_origin(const tpoint& /*origin*/)
 		{ ERROR_LOG(false); }
 
-	/** See thorizontal_list::set_visible_area(). */
+	/** See @ref thorizontal_list::set_visible_rectangle(). */
-	void set_visible_area(const SDL_Rect& /*area*/)
+	void set_visible_rectangle(const SDL_Rect& /*rectangle*/ )
 		{ ERROR_LOG(false); }
 
 	/** See thorizontal_list::find_at(). */
@@ -425,8 +425,8 @@ struct tindependent
 	/** See thorizontal_list::set_origin(). */
 	void set_origin(const tpoint& origin);
 
-	/** See thorizontal_list::set_visible_area(). */
+	/** See @ref thorizontal_list::set_visible_rectangle(). */
-	void set_visible_area(const SDL_Rect& area);
+	void set_visible_rectangle(const SDL_Rect& rectangle);
 
 	/** See thorizontal_list::find_at(). */
 	twidget* find_at(const tpoint& coordinate, const bool must_be_active);
@@ -503,7 +503,9 @@ struct tshow
 {
 	void select(tgrid& grid, const bool show)
 	{
-		grid.set_visible(show ? twidget::VISIBLE : twidget::HIDDEN);
+		grid.set_visible(show
+				? twidget::tvisible::visible
+				: twidget::tvisible::hidden);
 	}
 
 	/**
@@ -624,8 +626,8 @@ public:
 			/*** Set the proper visible state. ***/
 			items_[index]->shown = show;
 			items_[index]->grid.set_visible(show
-					? twidget::VISIBLE
+					? twidget::tvisible::visible
-					: twidget::INVISIBLE);
+					: twidget::tvisible::invisible);
 
 			/*** Update the selection. ***/
 			minimum_selection::set_item_shown(index, show);
@@ -747,12 +749,14 @@ public:
 		impl_create_items(index, list_builder, data, callback);
 	}
 
-	/** Inherited from tgenerator_. */
+	/** See @ref twidget::layout_initialise. */
-	void layout_init(const bool full_initialization)
+	virtual void layout_initialise(const bool full_initialisation) OVERRIDE
 	{
 		FOREACH(AUTO item, items_) {
-			if(item->grid.get_visible() != twidget::INVISIBLE && item->shown) {
+			if(item->grid.get_visible() != twidget::tvisible::invisible
-				item->grid.layout_init(full_initialization);
+						&& item->shown) {
+
+				item->grid.layout_initialise(full_initialisation);
 			}
 		}
 	}
@@ -793,19 +797,21 @@ public:
 		placement::set_origin(origin);
 	}
 
-	/** Inherited from tgenerator_. */
+	/** See @ref twidget::set_visible_rectangle. */
-	void set_visible_area(const SDL_Rect& area)
+	virtual void set_visible_rectangle(const SDL_Rect& rectangle) OVERRIDE
 	{
-		placement::set_visible_area(area);
+		placement::set_visible_rectangle(rectangle);
 	}
 
 	/** Inherited from tgenerator_. */
 	void impl_draw_children(surface& frame_buffer)
 	{
-		assert(this->get_visible() == twidget::VISIBLE);
+		assert(this->get_visible() == twidget::tvisible::visible);
 
 		FOREACH(AUTO item, items_) {
-			if(item->grid.get_visible() == twidget::VISIBLE && item->shown) {
+			if(item->grid.get_visible() == twidget::tvisible::visible
+					&& item->shown) {
+
 				item->grid.draw_children(frame_buffer);
 			}
 		}
@@ -814,10 +820,12 @@ public:
 	/** Inherited from tgenerator_. */
 	void impl_draw_children(surface& frame_buffer, int x_offset, int y_offset)
 	{
-		assert(this->get_visible() == twidget::VISIBLE);
+		assert(this->get_visible() == twidget::tvisible::visible);
 
 		FOREACH(AUTO item, items_) {
-			if(item->grid.get_visible() == twidget::VISIBLE && item->shown) {
+			if(item->grid.get_visible() == twidget::tvisible::visible
+					&& item->shown) {
+
 				item->grid.draw_children(frame_buffer, x_offset, y_offset);
 			}
 		}

src/gui/widgets/grid.cpp

@@ -182,15 +182,15 @@ void tgrid::set_active(const bool active)
 	}
 }
 
-void tgrid::layout_init(const bool full_initialization)
+void tgrid::layout_initialise(const bool full_initialisation)
 {
 	// Inherited.
-	twidget::layout_init(full_initialization);
+	twidget::layout_initialise(full_initialisation);
 
 	// Clear child caches.
 	FOREACH(AUTO& child, children_) {
 
-		child.layout_init(full_initialization);
+		child.layout_initialise(full_initialisation);
 
 	}
 }
@@ -564,17 +564,17 @@ void tgrid::set_origin(const tpoint& origin)
 	}
 }
 
-void tgrid::set_visible_area(const SDL_Rect& area)
+void tgrid::set_visible_rectangle(const SDL_Rect& rectangle)
 {
 	// Inherited.
-	twidget::set_visible_area(area);
+	twidget::set_visible_rectangle(rectangle);
 
 	FOREACH(AUTO& child, children_) {
 
 		twidget* widget = child.widget();
 		assert(widget);
 
-		widget->set_visible_area(area);
+		widget->set_visible_rectangle(rectangle);
 	}
 }
 
@@ -643,7 +643,7 @@ bool tgrid::has_widget(const twidget* widget) const
 
 bool tgrid::disable_click_dismiss() const
 {
-	if(get_visible() != twidget::VISIBLE) {
+	if(get_visible() != twidget::tvisible::visible) {
 		return false;
 	}
 
@@ -711,7 +711,7 @@ tpoint tgrid::tchild::get_best_size() const
 		return border_space();
 	}
 
-	if(widget_->get_visible() == twidget::INVISIBLE) {
+	if(widget_->get_visible() == twidget::tvisible::invisible) {
 		DBG_GUI_L << LOG_CHILD_HEADER
 			<< " has widget " << true
 			<< " widget visible " << false
@@ -733,7 +733,7 @@ tpoint tgrid::tchild::get_best_size() const
 void tgrid::tchild::place(tpoint origin, tpoint size)
 {
 	assert(widget());
-	if(widget()->get_visible() == twidget::INVISIBLE) {
+	if(widget()->get_visible() == twidget::tvisible::invisible) {
 		return;
 	}
 
@@ -871,12 +871,12 @@ void tgrid::tchild::place(tpoint origin, tpoint size)
 	widget()->place(widget_orig, widget_size);
 }
 
-void tgrid::tchild::layout_init(const bool full_initialization)
+void tgrid::tchild::layout_initialise(const bool full_initialisation)
 {
 	assert(widget_);
 
-	if(widget_->get_visible() != twidget::INVISIBLE) {
+	if(widget_->get_visible() != twidget::tvisible::invisible) {
-		widget_->layout_init(full_initialization);
+		widget_->layout_initialise(full_initialisation);
 	}
 }
 
@@ -939,7 +939,7 @@ void tgrid::impl_draw_children(surface& frame_buffer)
 	 */
 	SDL_PumpEvents();
 
-	assert(get_visible() == twidget::VISIBLE);
+	assert(get_visible() == twidget::tvisible::visible);
 	set_dirty(false);
 
 	FOREACH(AUTO& child, children_) {
@@ -947,11 +947,11 @@ void tgrid::impl_draw_children(surface& frame_buffer)
 		twidget* widget = child.widget();
 		assert(widget);
 
-		if(widget->get_visible() != twidget::VISIBLE) {
+		if(widget->get_visible() != twidget::tvisible::visible) {
 			continue;
 		}
 
-		if(widget->get_drawing_action() == twidget::NOT_DRAWN) {
+		if(widget->get_drawing_action() == twidget::tredraw_action::none) {
 			continue;
 		}
 
@@ -978,7 +978,7 @@ void tgrid::impl_draw_children(
 	 */
 	SDL_PumpEvents();
 
-	assert(get_visible() == twidget::VISIBLE);
+	assert(get_visible() == twidget::tvisible::visible);
 	set_dirty(false);
 
 	FOREACH(AUTO& child, children_) {
@@ -986,11 +986,11 @@ void tgrid::impl_draw_children(
 		twidget* widget = child.widget();
 		assert(widget);
 
-		if(widget->get_visible() != twidget::VISIBLE) {
+		if(widget->get_visible() != twidget::tvisible::visible) {
 			continue;
 		}
 
-		if(widget->get_drawing_action() == twidget::NOT_DRAWN) {
+		if(widget->get_drawing_action() == twidget::tredraw_action::none) {
 			continue;
 		}
 
@@ -1060,7 +1060,7 @@ void tgrid_implementation::cell_request_reduce_height(
 {
 	assert(child.widget_);
 
-	if(child.widget_->get_visible() == twidget::INVISIBLE) {
+	if(child.widget_->get_visible() == twidget::tvisible::invisible) {
 		return;
 	}
 
@@ -1073,7 +1073,7 @@ void tgrid_implementation::cell_request_reduce_width(
 {
 	assert(child.widget_);
 
-	if(child.widget_->get_visible() == twidget::INVISIBLE) {
+	if(child.widget_->get_visible() == twidget::tvisible::invisible) {
 		return;
 	}
 

src/gui/widgets/grid.hpp

@@ -83,7 +83,7 @@ public:
 	{
 		assert(row < row_grow_factor_.size());
 		row_grow_factor_[row] = factor;
-		set_dirty();
+		set_dirty(true);
 	}
 
 	/**
@@ -98,7 +98,7 @@ public:
 	{
 		assert(column< col_grow_factor_.size());
 		col_grow_factor_[column] = factor;
-		set_dirty();
+		set_dirty(true);
 	}
 
 	/***** ***** ***** ***** CHILD MANIPULATION ***** ***** ***** *****/
@@ -179,8 +179,8 @@ public:
 
 	/***** ***** ***** ***** layout functions ***** ***** ***** *****/
 
-	/** Inherited from twidget. */
+	/** See @ref twidget::layout_initialise. */
-	void layout_init(const bool full_initialization);
+	virtual void layout_initialise(const bool full_initialisation) OVERRIDE;
 
 	/**
 	 * Tries to reduce the width of a container.
@@ -240,8 +240,8 @@ public:
 	/** Inherited from twidget. */
 	void set_origin(const tpoint& origin);
 
-	/** Inherited from twidget. */
+	/** See @ref twidget::set_visible_rectangle. */
-	void set_visible_area(const SDL_Rect& area);
+	virtual void set_visible_rectangle(const SDL_Rect& rectangle) OVERRIDE;
 
 	/** Inherited from twidget. */
 	void layout_children();
@@ -315,8 +315,8 @@ private:
 		 */
 		void place(tpoint origin, tpoint size);
 
-		/** Forwards layout_init() to the cell. */
+		/** Forwards @ref tgrid::layout_initialise to the cell. */
-		void layout_init(const bool full_initialization);
+		void layout_initialise(const bool full_initialisation);
 
 		/** Returns the can_wrap for the cell. */
 		bool can_wrap() const

src/gui/widgets/list.cpp

@@ -156,7 +156,7 @@ void tlist::remove_row(const unsigned row, unsigned count)
 
 	unsigned height_reduced = 0;
 	for(; count; --count) {
-		if(generator_->item(row).get_visible() != INVISIBLE) {
+		if(generator_->item(row).get_visible() != tvisible::invisible) {
 			height_reduced += generator_->item(row).get_height();
 		}
 		generator_->delete_item(row);
@@ -208,8 +208,8 @@ void tlist::set_row_shown(const unsigned row, const bool shown)
 	if(resize_needed) {
 		window->invalidate_layout();
 	} else {
-//		grid().set_visible_area(content_visible_area());
+//		grid().set_visible_rectangle(content_visible_rectangle());
-		set_dirty();
+		set_dirty(true);
 	}
 
 	if(selected_row != get_selected_row()) {
@@ -242,8 +242,8 @@ void tlist::set_row_shown(const std::vector<bool>& shown)
 	if(resize_needed) {
 		window->invalidate_layout();
 	} else {
-//		content_grid_->set_visible_area(content_visible_area());
+//		content_grid_->set_visible_rectangle(content_visible_rectangle());
-		set_dirty();
+		set_dirty(true);
 	}
 
 	if(selected_row != get_selected_row()) {
@@ -297,7 +297,7 @@ void tlist::place(const tpoint& origin, const tpoint& size)
 	if(selected_item != -1) {
 /*
 		const SDL_Rect& visible = content_visible_area();
-		SDL_Rect rect = generator_->item(selected_item).get_rect();
+		SDL_Rect rect = generator_->item(selected_item).get_rectangle();
 
 		rect.x = visible.x;
 		rect.w = visible.w;
@@ -330,7 +330,7 @@ void tlist::resize_content(
 		need_layout_ = true;
 		// If the content grows assume it "overwrites" the old content.
 		if(width_modification < 0 || height_modification < 0) {
-			set_dirty();
+			set_dirty(true);
 		}
 		DBG_GUI_L << LOG_HEADER << " succeeded.\n";
 	} else {
@@ -352,16 +352,16 @@ void tlist::init()
 	 * So make them invisible for now.
 	 */
 	tgrid* g = find_widget<tgrid>(&grid(), "_header_grid", false, false);
-	if(g) g->set_visible(twidget::INVISIBLE);
+	if(g) g->set_visible(twidget::tvisible::invisible);
 
 	g = find_widget<tgrid>(&grid(), "_footer_grid", false, false);
-	if(g) g->set_visible(twidget::INVISIBLE);
+	if(g) g->set_visible(twidget::tvisible::invisible);
 
 	g = find_widget<tgrid>(&grid(), "_vertical_scrollbar_grid", false, false);
-	if(g) g->set_visible(twidget::INVISIBLE);
+	if(g) g->set_visible(twidget::tvisible::invisible);
 
 	g = find_widget<tgrid>(&grid(), "_horizontal_scrollbar_grid", false, false);
-	if(g) g->set_visible(twidget::INVISIBLE);
+	if(g) g->set_visible(twidget::tvisible::invisible);
 
 }
 
@@ -371,10 +371,10 @@ void tlist::layout_children(const bool force)
 		grid().place(grid().get_origin(), grid().get_size());
 
 /*
-		grid().set_visible_area(content_visible_area_);
+		grid().set_visible_rectangle(content_visible_area_);
 */
 		need_layout_ = false;
-		set_dirty();
+		set_dirty(true);
 	}
 }
 

src/gui/widgets/listbox.cpp

@@ -90,7 +90,7 @@ void tlistbox::remove_row(const unsigned row, unsigned count)
 
 	int height_reduced = 0;
 	for(; count; --count) {
-		if(generator_->item(row).get_visible() != INVISIBLE) {
+		if(generator_->item(row).get_visible() != tvisible::invisible) {
 			height_reduced += generator_->item(row).get_height();
 		}
 		generator_->delete_item(row);
@@ -142,8 +142,8 @@ void tlistbox::set_row_shown(const unsigned row, const bool shown)
 	if(resize_needed) {
 		window->invalidate_layout();
 	} else {
-		content_grid_->set_visible_area(content_visible_area());
+		content_grid_->set_visible_rectangle(content_visible_area());
-		set_dirty();
+		set_dirty(true);
 	}
 
 	if(selected_row != get_selected_row() && callback_value_changed_) {
@@ -176,8 +176,8 @@ void tlistbox::set_row_shown(const std::vector<bool>& shown)
 	if(resize_needed) {
 		window->invalidate_layout();
 	} else {
-		content_grid_->set_visible_area(content_visible_area());
+		content_grid_->set_visible_rectangle(content_visible_area());
-		set_dirty();
+		set_dirty(true);
 	}
 
 	if(selected_row != get_selected_row() && callback_value_changed_) {
@@ -237,7 +237,7 @@ void tlistbox::list_item_clicked(twidget* caller)
 
 bool tlistbox::update_content_size()
 {
-	if(get_visible() == twidget::INVISIBLE) {
+	if(get_visible() == twidget::tvisible::invisible) {
 		return true;
 	}
 
@@ -246,8 +246,8 @@ bool tlistbox::update_content_size()
 	}
 
 	if(content_resize_request(true)) {
-		content_grid_->set_visible_area(content_visible_area());
+		content_grid_->set_visible_rectangle(content_visible_area());
-		set_dirty();
+		set_dirty(true);
 		return true;
 	}
 
@@ -270,7 +270,7 @@ void tlistbox::place(const tpoint& origin, const tpoint& size)
 	const int selected_item = generator_->get_selected_item();
 	if(selected_item != -1) {
 		const SDL_Rect& visible = content_visible_area();
-		SDL_Rect rect = generator_->item(selected_item).get_rect();
+		SDL_Rect rect = generator_->item(selected_item).get_rectangle();
 
 		rect.x = visible.x;
 		rect.w = visible.w;
@@ -302,7 +302,7 @@ void tlistbox::resize_content(
 		need_layout_ = true;
 		// If the content grows assume it "overwrites" the old content.
 		if(width_modification < 0 || height_modification < 0) {
-			set_dirty();
+			set_dirty(true);
 		}
 		DBG_GUI_L << LOG_HEADER << " succeeded.\n";
 	} else {
@@ -337,7 +337,7 @@ void tlistbox::handle_key_up_arrow(SDLMod modifier, bool& handled)
 		// horizontal scrollbar position.
 		const SDL_Rect& visible = content_visible_area();
 		SDL_Rect rect = generator_->item(
-				generator_->get_selected_item()).get_rect();
+				generator_->get_selected_item()).get_rectangle();
 
 		rect.x = visible.x;
 		rect.w = visible.w;
@@ -364,7 +364,7 @@ void tlistbox::handle_key_down_arrow(SDLMod modifier, bool& handled)
 		// horizontal scrollbar position.
 		const SDL_Rect& visible = content_visible_area();
 		SDL_Rect rect = generator_->item(
-				generator_->get_selected_item()).get_rect();
+				generator_->get_selected_item()).get_rectangle();
 
 		rect.x = visible.x;
 		rect.w = visible.w;
@@ -392,7 +392,7 @@ void tlistbox::handle_key_left_arrow(SDLMod modifier, bool& handled)
 		// vertical scrollbar position.
 		const SDL_Rect& visible = content_visible_area();
 		SDL_Rect rect = generator_->item(
-				generator_->get_selected_item()).get_rect();
+				generator_->get_selected_item()).get_rectangle();
 
 		rect.y = visible.y;
 		rect.h = visible.h;
@@ -419,7 +419,7 @@ void tlistbox::handle_key_right_arrow(SDLMod modifier, bool& handled)
 		// vertical scrollbar position.
 		const SDL_Rect& visible = content_visible_area();
 		SDL_Rect rect = generator_->item(
-				generator_->get_selected_item()).get_rect();
+				generator_->get_selected_item()).get_rectangle();
 
 		rect.y = visible.y;
 		rect.h = visible.h;
@@ -511,10 +511,10 @@ void tlistbox::layout_children(const bool force)
 				  content_grid()->get_origin()
 				, content_grid()->get_size());
 
-		content_grid()->set_visible_area(content_visible_area_);
+		content_grid()->set_visible_rectangle(content_visible_area_);
 
 		need_layout_ = false;
-		set_dirty();
+		set_dirty(true);
 	}
 }
 

src/gui/widgets/matrix.cpp

@@ -108,9 +108,9 @@ void tmatrix::place(const tpoint& origin, const tpoint& size)
 	content_.place(origin, size);
 }
 
-void tmatrix::layout_init(const bool full_initialization)
+void tmatrix::layout_initialise(const bool full_initialisation)
 {
-	content_.layout_init(full_initialization);
+	content_.layout_initialise(full_initialisation);
 }
 
 void tmatrix::impl_draw_children(

src/gui/widgets/matrix.hpp

@@ -114,8 +114,8 @@ public:
 	/** Inherited from twidget. */
 	void place(const tpoint& origin, const tpoint& size);
 
-	/** Inherited from twidget. */
+	/** See @ref twidget::layout_initialise. */
-	void layout_init(const bool full_initialization);
+	virtual void layout_initialise(const bool full_initialisation) OVERRIDE;
 
 	/** Inherited from twidget. */
 	void impl_draw_children(surface& frame_buffer, int x_offset, int y_offset);

src/gui/widgets/minimap.cpp

@@ -217,14 +217,14 @@ void tminimap::impl_draw_background(surface& frame_buffer)
 	assert(terrain_);
 
 	DBG_GUI_D << LOG_HEADER
-			<< " size " << get_rect()
+			<< " size " << get_rectangle()
 			<< ".\n";
 
 	if(map_data_.empty()) {
 		return;
 	}
 
-	SDL_Rect rect = get_rect();
+	SDL_Rect rect = get_rectangle();
 	assert(rect.w > 0 && rect.h > 0);
 
 	const ::surface surf = get_image(rect.w, rect.h);

src/gui/widgets/minimap.hpp

@@ -55,7 +55,7 @@ public:
 	/***** ***** ***** setters / getters for members ***** ****** *****/
 
 	void set_map_data(const std::string& map_data)
-		{ if(map_data != map_data_) { map_data_ = map_data; set_dirty(); } }
+		{ if(map_data != map_data_) { map_data_ = map_data; set_dirty(true); } }
 
 	std::string get_map_data() const { return map_data_; }
 

src/gui/widgets/pane.cpp

@@ -66,7 +66,7 @@ struct tpane_implementation
 		typedef typename utils::tconst_clone<tpane::titem, W>::reference thack;
 		BOOST_FOREACH(thack item, pane->items_) {
 
-			if(item.grid->get_visible() == twidget::INVISIBLE) {
+			if(item.grid->get_visible() == twidget::tvisible::invisible) {
 				continue;
 			}
 
@@ -74,7 +74,7 @@ struct tpane_implementation
 			 * If the adjusted coordinate is in the item's grid let the grid
 			 * resolve the coordinate.
 			 */
-			const SDL_Rect rect = item.grid->get_rect();
+			const SDL_Rect rect = item.grid->get_rectangle();
 			if(
 					   coordinate.x >= rect.x
 					&& coordinate.y >= rect.y
@@ -190,15 +190,15 @@ void tpane::place(const tpoint& origin, const tpoint& size)
 	place_children();
 }
 
-void tpane::layout_init(const bool full_initialization)
+void tpane::layout_initialise(const bool full_initialisation)
 {
 	DBG_GUI_D << LOG_HEADER << '\n';
 
-	twidget::layout_init(full_initialization);
+	twidget::layout_initialise(full_initialisation);
 
 	FOREACH(AUTO& item, items_) {
-		if(item.grid->get_visible() != twidget::INVISIBLE) {
+		if(item.grid->get_visible() != twidget::tvisible::invisible) {
-			item.grid->layout_init(full_initialization);
+			item.grid->layout_initialise(full_initialisation);
 		}
 	}
 }
@@ -211,7 +211,7 @@ void tpane::impl_draw_children(
 	DBG_GUI_D << LOG_HEADER << '\n';
 
 	FOREACH(AUTO& item, items_) {
-		if(item.grid->get_visible() != twidget::INVISIBLE) {
+		if(item.grid->get_visible() != twidget::tvisible::invisible) {
 			item.grid->draw_children(frame_buffer, x_offset, y_offset);
 		}
 	}
@@ -238,8 +238,8 @@ void tpane::filter(const tfilter_functor& filter_functor)
 	FOREACH(AUTO& item, items_) {
 		item.grid->set_visible(
 				filter_functor(item)
-					? twidget::VISIBLE
+					? twidget::tvisible::visible
-					: twidget::INVISIBLE);
+					: twidget::tvisible::invisible);
 	}
 
 	set_origin_children();
@@ -303,7 +303,7 @@ void tpane::place_children()
 	prepare_placement();
 	unsigned index = 0;
 	FOREACH(AUTO& item, items_) {
-		if(item.grid->get_visible() == twidget::INVISIBLE) {
+		if(item.grid->get_visible() == twidget::tvisible::invisible) {
 			continue;
 		}
 
@@ -318,7 +318,7 @@ void tpane::set_origin_children()
 	prepare_placement();
 	unsigned index = 0;
 	FOREACH(AUTO& item, items_) {
-		if(item.grid->get_visible() == twidget::INVISIBLE) {
+		if(item.grid->get_visible() == twidget::tvisible::invisible) {
 			continue;
 		}
 
@@ -333,7 +333,7 @@ void tpane::place_or_set_origin_children()
 	prepare_placement();
 	unsigned index = 0;
 	FOREACH(AUTO& item, items_) {
-		if(item.grid->get_visible() == twidget::INVISIBLE) {
+		if(item.grid->get_visible() == twidget::tvisible::invisible) {
 			continue;
 		}
 
@@ -353,7 +353,7 @@ void tpane::prepare_placement() const
 	placer_->initialise();
 
 	FOREACH(const AUTO& item, items_) {
-		if(item.grid->get_visible() == twidget::INVISIBLE) {
+		if(item.grid->get_visible() == twidget::tvisible::invisible) {
 			continue;
 		}
 
@@ -372,7 +372,7 @@ void tpane::signal_handler_request_placement(
 	if(widget) {
 		FOREACH(AUTO& item, items_) {
 			if(item.grid->has_widget(widget)) {
-				if(item.grid->get_visible() != twidget::INVISIBLE) {
+				if(item.grid->get_visible() != twidget::tvisible::invisible) {
 
 					/*
 					 * This time we call init layout but also the linked widget
@@ -380,7 +380,7 @@ void tpane::signal_handler_request_placement(
 					 * addon_list. This code can use some more tuning,
 					 * polishing and testing.
 					 */
-					item.grid->layout_init(false);
+					item.grid->layout_initialise(false);
 					get_window()->layout_linked_widgets();
 
 					/*

src/gui/widgets/pane.hpp

@@ -24,6 +24,8 @@
 
 #include <list>
 
+typedef std::map< std::string, t_string > string_map;
+
 namespace gui2 {
 
 namespace implementation {
@@ -79,8 +81,8 @@ public:
 	/** Inherited from twidget. */
 	void place(const tpoint& origin, const tpoint& size);
 
-	/** Inherited from twidget. */
+	/** See @ref twidget::layout_initialise. */
-	void layout_init(const bool full_initialization);
+	virtual void layout_initialise(const bool full_initialisation) OVERRIDE;
 
 	/** Inherited from twidget. */
 	void impl_draw_children(surface& frame_buffer, int x_offset, int y_offset);

src/gui/widgets/panel.cpp

@@ -38,7 +38,7 @@ SDL_Rect tpanel::get_client_rect() const
 		boost::dynamic_pointer_cast<const tpanel_definition::tresolution>(config());
 	assert(conf);
 
-	SDL_Rect result = get_rect();
+	SDL_Rect result = get_rectangle();
 	result.x += conf->left_border;
 	result.y += conf->top_border;
 	result.w -= conf->left_border + conf->right_border;
@@ -50,10 +50,10 @@ SDL_Rect tpanel::get_client_rect() const
 void tpanel::impl_draw_background(surface& frame_buffer)
 {
 	DBG_GUI_D << LOG_HEADER
-			<< " size " << get_rect()
+			<< " size " << get_rectangle()
 			<< ".\n";
 
-	canvas(0).blit(frame_buffer, get_rect());
+	canvas(0).blit(frame_buffer, get_rectangle());
 }
 
 void tpanel::impl_draw_background(
@@ -62,7 +62,7 @@ void tpanel::impl_draw_background(
 		, int y_offset)
 {
 	DBG_GUI_D << LOG_HEADER
-			<< " size " << get_rect()
+			<< " size " << get_rectangle()
 			<< ".\n";
 
 	canvas(0).blit(
@@ -72,7 +72,7 @@ void tpanel::impl_draw_background(
 
 void tpanel::impl_draw_foreground(surface& frame_buffer)
 {
-	canvas(1).blit(frame_buffer, get_rect());
+	canvas(1).blit(frame_buffer, get_rectangle());
 }
 
 void tpanel::impl_draw_foreground(

src/gui/widgets/password_box.cpp

@@ -129,7 +129,7 @@ void tpassword_box::post_function() {
 	// Why do the selection functions not update
 	// the canvas?
 	update_canvas();
-	set_dirty();
+	set_dirty(true);
 }
 
 const std::string& tpassword_box::get_control_type() const

src/gui/widgets/progress_bar.cpp

@@ -44,7 +44,7 @@ void tprogress_bar::set_percentage(const unsigned percentage)
 			c.set_variable("percentage", variant(percentage));
 		}
 
-		set_dirty();
+		set_dirty(true);
 	}
 }
 

src/gui/widgets/scrollbar.cpp

@@ -136,7 +136,7 @@ void tscrollbar_::update_canvas() {
 		tmp.set_variable("positioner_offset", variant(positioner_offset_));
 		tmp.set_variable("positioner_length", variant(positioner_length_));
 	}
-	set_dirty();
+	set_dirty(true);
 }
 
 void tscrollbar_::set_state(const tstate state)

src/gui/widgets/scrollbar_container.cpp

@@ -115,44 +115,50 @@ tscrollbar_container::tscrollbar_container(const unsigned canvas_count)
 			, event::tdispatcher::back_post_child);
 }
 
-void tscrollbar_container::layout_init(const bool full_initialization)
+void tscrollbar_container::layout_initialise(const bool full_initialisation)
 {
 	// Inherited.
-	tcontainer_::layout_init(full_initialization);
+	tcontainer_::layout_initialise(full_initialisation);
 
-	if(full_initialization) {
+	if(full_initialisation) {
 
 		assert(vertical_scrollbar_grid_);
 		switch(vertical_scrollbar_mode_) {
 			case always_visible :
-				vertical_scrollbar_grid_->set_visible(twidget::VISIBLE);
+				vertical_scrollbar_grid_
+						->set_visible(twidget::tvisible::visible);
 				break;
 
 			case auto_visible :
-				vertical_scrollbar_grid_->set_visible(twidget::HIDDEN);
+				vertical_scrollbar_grid_
+						->set_visible(twidget::tvisible::hidden);
 				break;
 
 			default :
-				vertical_scrollbar_grid_->set_visible(twidget::INVISIBLE);
+				vertical_scrollbar_grid_
+						->set_visible(twidget::tvisible::invisible);
 		}
 
 		assert(horizontal_scrollbar_grid_);
 		switch(horizontal_scrollbar_mode_) {
 			case always_visible :
-				horizontal_scrollbar_grid_->set_visible(twidget::VISIBLE);
+				horizontal_scrollbar_grid_
+						->set_visible(twidget::tvisible::visible);
 				break;
 
 			case auto_visible :
-				horizontal_scrollbar_grid_->set_visible(twidget::HIDDEN);
+				horizontal_scrollbar_grid_
+						->set_visible(twidget::tvisible::hidden);
 				break;
 
 			default :
-				horizontal_scrollbar_grid_->set_visible(twidget::INVISIBLE);
+				horizontal_scrollbar_grid_
+						->set_visible(twidget::tvisible::invisible);
 		}
 	}
 
 	assert(content_grid_);
-	content_grid_->layout_init(full_initialization);
+	content_grid_->layout_initialise(full_initialisation);
 }
 
 void tscrollbar_container::request_reduce_height(
@@ -167,10 +173,13 @@ void tscrollbar_container::request_reduce_height(
 	 */
 	/** @todo Evaluate whether sizing hints are required. */
 	assert(content_grid_);
-	const unsigned offset = horizontal_scrollbar_grid_
+	const unsigned offset
-			&& horizontal_scrollbar_grid_->get_visible() != twidget::INVISIBLE
+			= horizontal_scrollbar_grid_
-				?  horizontal_scrollbar_grid_->get_best_size().y
+				&& horizontal_scrollbar_grid_->get_visible()
-				: 0;
+					!= twidget::tvisible::invisible
+			?  horizontal_scrollbar_grid_->get_best_size().y
+			: 0;
+
 	content_grid_->request_reduce_height(maximum_height - offset);
 
 	// Did we manage to achieve the wanted size?
@@ -189,16 +198,16 @@ void tscrollbar_container::request_reduce_height(
 
 	assert(vertical_scrollbar_grid_);
 	const bool resized =
-		vertical_scrollbar_grid_->get_visible() == twidget::INVISIBLE;
+		vertical_scrollbar_grid_->get_visible() == twidget::tvisible::invisible;
 
 	// Always set the bar visible, is a nop is already visible.
-	vertical_scrollbar_grid_->set_visible(twidget::VISIBLE);
+	vertical_scrollbar_grid_->set_visible(twidget::tvisible::visible);
 
 	const tpoint scrollbar_size = vertical_scrollbar_grid_->get_best_size();
 
 	// If showing the scrollbar increased the height, hide and abort.
 	if(resized && scrollbar_size.y > size.y) {
-		vertical_scrollbar_grid_->set_visible(twidget::INVISIBLE);
+		vertical_scrollbar_grid_->set_visible(twidget::tvisible::invisible);
 		DBG_GUI_L << LOG_HEADER
 				<< " request failed, showing the scrollbar"
 			    << " increased the height to " << scrollbar_size.y
@@ -237,10 +246,13 @@ void tscrollbar_container::request_reduce_width(
 	// First ask our content, it might be able to wrap which looks better as
 	// a scrollbar.
 	assert(content_grid_);
-	const unsigned offset = vertical_scrollbar_grid_
+	const unsigned offset
-			&& vertical_scrollbar_grid_->get_visible() != twidget::INVISIBLE
+			= vertical_scrollbar_grid_
-				?  vertical_scrollbar_grid_->get_best_size().x
+			&& vertical_scrollbar_grid_->get_visible()
-				: 0;
+				!= twidget::tvisible::invisible
+			?  vertical_scrollbar_grid_->get_best_size().x
+			: 0;
+
 	content_grid_->request_reduce_width(maximum_width - offset);
 
 	// Did we manage to achieve the wanted size?
@@ -259,7 +271,7 @@ void tscrollbar_container::request_reduce_width(
 
 	// Always set the bar visible, is a nop when it's already visible.
 	assert(horizontal_scrollbar_grid_);
-	horizontal_scrollbar_grid_->set_visible(twidget::VISIBLE);
+	horizontal_scrollbar_grid_->set_visible(twidget::tvisible::visible);
 	size = get_best_size();
 
 	const tpoint scrollbar_size = horizontal_scrollbar_grid_->get_best_size();
@@ -268,7 +280,7 @@ void tscrollbar_container::request_reduce_width(
 	if(horizontal_scrollbar_mode_ == auto_visible_first_run
 			&& scrollbar_size.x > size.x) {
 
-		horizontal_scrollbar_grid_->set_visible(twidget::INVISIBLE);
+		horizontal_scrollbar_grid_->set_visible(twidget::tvisible::invisible);
 		DBG_GUI_L << LOG_HEADER
 				<< " request failed, showing the scrollbar"
 			    << " increased the width to " << scrollbar_size.x
@@ -295,14 +307,16 @@ tpoint tscrollbar_container::calculate_best_size() const
 	log_scope2(log_gui_layout, LOG_SCOPE_HEADER);
 
 	/***** get vertical scrollbar size *****/
-	const tpoint vertical_scrollbar =
+	const tpoint vertical_scrollbar
-			vertical_scrollbar_grid_->get_visible() == twidget::INVISIBLE
+			= vertical_scrollbar_grid_->get_visible()
+				== twidget::tvisible::invisible
 			? tpoint(0, 0)
 			: vertical_scrollbar_grid_->get_best_size();
 
 	/***** get horizontal scrollbar size *****/
-	const tpoint horizontal_scrollbar =
+	const tpoint horizontal_scrollbar
-			horizontal_scrollbar_grid_->get_visible() == twidget::INVISIBLE
+			= horizontal_scrollbar_grid_->get_visible()
+				== twidget::tvisible::invisible
 			? tpoint(0, 0)
 			: horizontal_scrollbar_grid_->get_best_size();
 
@@ -333,7 +347,7 @@ static void set_scrollbar_mode(tgrid* scrollbar_grid, tscrollbar_* scrollbar,
 	assert(scrollbar_grid && scrollbar);
 
 	if(scrollbar_mode == tscrollbar_container::always_invisible) {
-		scrollbar_grid->set_visible(twidget::INVISIBLE);
+		scrollbar_grid->set_visible(twidget::tvisible::invisible);
 		return;
 	}
 
@@ -346,8 +360,8 @@ static void set_scrollbar_mode(tgrid* scrollbar_grid, tscrollbar_* scrollbar,
 		const bool scrollbar_needed = items > visible_items;
 
 		scrollbar_grid->set_visible(scrollbar_needed
-				? twidget::VISIBLE
+				? twidget::tvisible::visible
-				: twidget::HIDDEN);
+				: twidget::tvisible::hidden);
 	}
 }
 
@@ -386,8 +400,8 @@ void tscrollbar_container::place(const tpoint& origin, const tpoint& size)
 	set_scrollbar_button_status();
 
 	// Now set the visible part of the content.
-	content_visible_area_ = content_->get_rect();
+	content_visible_area_ = content_->get_rectangle();
-	content_grid_->set_visible_area(content_visible_area_);
+	content_grid_->set_visible_rectangle(content_visible_area_);
 }
 
 void tscrollbar_container::set_origin(const tpoint& origin)
@@ -403,18 +417,19 @@ void tscrollbar_container::set_origin(const tpoint& origin)
 	content_grid_->set_origin(content_origin);
 
 	// Changing the origin also invalidates the visible area.
-	content_grid_->set_visible_area(content_visible_area_);
+	content_grid_->set_visible_rectangle(content_visible_area_);
 }
 
-void tscrollbar_container::set_visible_area(const SDL_Rect& area)
+void tscrollbar_container::set_visible_rectangle(const SDL_Rect& rectangle)
 {
 	// Inherited.
-	tcontainer_::set_visible_area(area);
+	tcontainer_::set_visible_rectangle(rectangle);
 
 	// Now get the visible part of the content.
-	content_visible_area_ = intersect_rects(area, content_->get_rect());
+	content_visible_area_
+			= intersect_rects(rectangle, content_->get_rectangle());
 
-	content_grid_->set_visible_area(content_visible_area_);
+	content_grid_->set_visible_rectangle(content_visible_area_);
 }
 
 twidget* tscrollbar_container::find_at(
@@ -497,7 +512,7 @@ bool tscrollbar_container::content_resize_request(const bool force_sizing)
 		if(horizontal_scrollbar_mode_ == always_invisible
 				|| (horizontal_scrollbar_mode_ == auto_visible_first_run
 					&& horizontal_scrollbar_grid_->get_visible()
-						== twidget::INVISIBLE)) {
+						== twidget::tvisible::invisible)) {
 
 			DBG_GUI_L << LOG_HEADER
 					<< " can't use horizontal scrollbar, ask window.\n";
@@ -513,7 +528,7 @@ bool tscrollbar_container::content_resize_request(const bool force_sizing)
 		if(vertical_scrollbar_mode_ == always_invisible
 				|| (vertical_scrollbar_mode_ == auto_visible_first_run
 					&& vertical_scrollbar_grid_->get_visible()
-						== twidget::INVISIBLE)) {
+						== twidget::tvisible::invisible)) {
 
 			DBG_GUI_L << LOG_HEADER
 					<< " can't use vertical scrollbar, ask window.\n";
@@ -597,7 +612,7 @@ bool tscrollbar_container::content_resize_width(const int width_modification)
 	if(horizontal_scrollbar_mode_ == always_invisible
 			|| (horizontal_scrollbar_mode_ == auto_visible_first_run
 				&& horizontal_scrollbar_grid_->get_visible()
-					== twidget::INVISIBLE)) {
+					== twidget::tvisible::invisible)) {
 
 		DBG_GUI_L << " can't use horizontal scrollbar, ask window.\n";
 		twindow* window = get_window();
@@ -645,7 +660,7 @@ bool tscrollbar_container::content_resize_height(const int height_modification)
 	if(vertical_scrollbar_mode_ == always_invisible
 			|| (vertical_scrollbar_mode_ == auto_visible_first_run
 				&& vertical_scrollbar_grid_->get_visible()
-					== twidget::INVISIBLE)) {
+					== twidget::tvisible::invisible)) {
 
 		DBG_GUI_L << " can't use vertical scrollbar, ask window.\n";
 		twindow* window = get_window();
@@ -749,8 +764,8 @@ void tscrollbar_container::
 
 void tscrollbar_container::impl_draw_children(surface& frame_buffer)
 {
-	assert(get_visible() == twidget::VISIBLE
+	assert(get_visible() == twidget::tvisible::visible
-			&& content_grid_->get_visible() == twidget::VISIBLE);
+			&& content_grid_->get_visible() == twidget::tvisible::visible);
 
 	// Inherited.
 	tcontainer_::impl_draw_children(frame_buffer);
@@ -763,8 +778,8 @@ void tscrollbar_container::impl_draw_children(
 		, int x_offset
 		, int y_offset)
 {
-	assert(get_visible() == twidget::VISIBLE
+	assert(get_visible() == twidget::tvisible::visible
-			&& content_grid_->get_visible() == twidget::VISIBLE);
+			&& content_grid_->get_visible() == twidget::tvisible::visible);
 
 	// Inherited.
 	tcontainer_::impl_draw_children(frame_buffer, x_offset, y_offset);
@@ -1031,8 +1046,8 @@ void tscrollbar_container::scrollbar_moved()
 			content_->get_y() - y_offset);
 
 	content_grid_->set_origin(content_origin);
-	content_grid_->set_visible_area(content_visible_area_);
+	content_grid_->set_visible_rectangle(content_visible_area_);
-	content_grid_->set_dirty();
+	content_grid_->set_dirty(true);
 
 	// Update scrollbar.
 	set_scrollbar_button_status();
@@ -1100,7 +1115,7 @@ void tscrollbar_container::signal_handler_sdl_wheel_up(
 
 	assert(vertical_scrollbar_grid_ && vertical_scrollbar_);
 
-	if(vertical_scrollbar_grid_->get_visible() == twidget::VISIBLE) {
+	if(vertical_scrollbar_grid_->get_visible() == twidget::tvisible::visible) {
 		vertical_scrollbar_->scroll(tscrollbar_::HALF_JUMP_BACKWARDS);
 		scrollbar_moved();
 		handled = true;
@@ -1115,7 +1130,7 @@ void tscrollbar_container::signal_handler_sdl_wheel_down(
 
 	assert(vertical_scrollbar_grid_ && vertical_scrollbar_);
 
-	if(vertical_scrollbar_grid_->get_visible() == twidget::VISIBLE) {
+	if(vertical_scrollbar_grid_->get_visible() == twidget::tvisible::visible) {
 		vertical_scrollbar_->scroll(tscrollbar_::HALF_JUMP_FORWARD);
 		scrollbar_moved();
 		handled = true;
@@ -1130,7 +1145,7 @@ void tscrollbar_container::signal_handler_sdl_wheel_left(
 
 	assert(horizontal_scrollbar_grid_ && horizontal_scrollbar_);
 
-	if(horizontal_scrollbar_grid_->get_visible() == twidget::VISIBLE) {
+	if(horizontal_scrollbar_grid_->get_visible() == twidget::tvisible::visible) {
 		horizontal_scrollbar_->scroll(tscrollbar_::HALF_JUMP_BACKWARDS);
 		scrollbar_moved();
 		handled = true;
@@ -1145,7 +1160,7 @@ void tscrollbar_container::signal_handler_sdl_wheel_right(
 
 	assert(horizontal_scrollbar_grid_ && horizontal_scrollbar_);
 
-	if(horizontal_scrollbar_grid_->get_visible() == twidget::VISIBLE) {
+	if(horizontal_scrollbar_grid_->get_visible() == twidget::tvisible::visible) {
 		horizontal_scrollbar_->scroll(tscrollbar_::HALF_JUMP_FORWARD);
 		scrollbar_moved();
 		handled = true;

src/gui/widgets/scrollbar_container.hpp

@@ -85,8 +85,8 @@ public:
 
 	/***** ***** ***** ***** layout functions ***** ***** ***** *****/
 
-	/** Inherited from tcontainer_. */
+	/** See @ref twidget::layout_initialise. */
-	void layout_init(const bool full_initialization);
+	virtual void layout_initialise(const bool full_initialisation) OVERRIDE;
 
 	/** Inherited from twidget. */
 	void request_reduce_height(const unsigned maximum_height);
@@ -114,8 +114,8 @@ public:
 	/** Inherited from tcontainer_. */
 	void set_origin(const tpoint& origin);
 
-	/** Inherited from tcontainer_. */
+	/** See @ref twidget::set_visible_rectangle. */
-	void set_visible_area(const SDL_Rect& area);
+	virtual void set_visible_rectangle(const SDL_Rect& rectangle) OVERRIDE;
 
 	/***** ***** ***** inherited ****** *****/
 

src/gui/widgets/settings.cpp

@@ -34,6 +34,7 @@
 #include "serialization/schema_validator.hpp"
 #include "formula_string_utils.hpp"
 #include "utils/foreach.tpp"
+#include "wml_exception.hpp"
 
 namespace gui2 {
 

src/gui/widgets/slider.hpp

@@ -61,7 +61,7 @@ public:
 	/***** ***** ***** setters / getters for members ***** ****** *****/
 
 	void set_best_slider_length(const unsigned length)
-		{ best_slider_length_ = length; set_dirty(); }
+		{ best_slider_length_ = length; set_dirty(true); }
 
 	void set_minimum_value_label(const t_string& minimum_value_label)
 		{ minimum_value_label_ = minimum_value_label; }

src/gui/widgets/text.cpp

@@ -66,7 +66,7 @@ void ttext_::set_maximum_length(const size_t maximum_length)
 			selection_length_ = maximum_length - selection_start_;
 		}
 		update_canvas();
-		set_dirty();
+		set_dirty(true);
 	}
 }
 
@@ -79,7 +79,7 @@ void ttext_::set_value(const std::string& text)
 		selection_start_ = text_.get_length();
 		selection_length_ = 0;
 		update_canvas();
-		set_dirty();
+		set_dirty(true);
 	}
 }
 
@@ -98,7 +98,7 @@ void ttext_::set_cursor(const size_t offset, const bool select)
 		copy_selection(true);
 #endif
 		update_canvas();
-		set_dirty();
+		set_dirty(true);
 
 	} else {
 		assert(offset <= text_.get_length());
@@ -106,7 +106,7 @@ void ttext_::set_cursor(const size_t offset, const bool select)
 		selection_length_ = 0;
 
 		update_canvas();
-		set_dirty();
+		set_dirty(true);
 	}
 }
 
@@ -119,7 +119,7 @@ void ttext_::insert_char(const Uint16 unicode)
 		// Update status
 		set_cursor(selection_start_ + 1, false);
 		update_canvas();
-		set_dirty();
+		set_dirty(true);
 	}
 }
 
@@ -156,7 +156,7 @@ void ttext_::paste_selection(const bool mouse)
 	selection_start_ += text_.insert_text(selection_start_, text);
 
 	update_canvas();
-	set_dirty();
+	set_dirty(true);
 	fire(event::NOTIFY_MODIFIED, *this, NULL);
 }
 
@@ -164,7 +164,7 @@ void  ttext_::set_selection_start(const size_t selection_start)
 {
 	if(selection_start != selection_start_) {
 		selection_start_ = selection_start;
-		set_dirty();
+		set_dirty(true);
 	}
 }
 
@@ -172,7 +172,7 @@ void ttext_::set_selection_length(const int selection_length)
 {
 	if(selection_length != selection_length_) {
 		selection_length_ = selection_length;
-		set_dirty();
+		set_dirty(true);
 	}
 }
 

src/gui/widgets/text_box.cpp

@@ -235,7 +235,7 @@ void ttext_box::handle_mouse_selection(tpoint mouse, const bool start_selection)
 
 	set_cursor(offset, !start_selection);
 	update_canvas();
-	set_dirty();
+	set_dirty(true);
 	dragging_ |= start_selection;
 }
 
@@ -265,7 +265,7 @@ void ttext_box::update_offsets()
 		tmp.set_variable("text_font_height", variant(text_height_));
 	}
 
- 	// Force an update of the canvas since now text_font_height is known.
+	// Force an update of the canvas since now text_font_height is known.
 	update_canvas();
 }
 

src/gui/widgets/toggle_button.cpp

@@ -94,7 +94,7 @@ void ttoggle_button::update_canvas()
 		canvas.set_variable("icon", variant(icon_name_));
 	}
 
-	set_dirty();
+	set_dirty(true);
 }
 
 void ttoggle_button::set_value(const bool selected)

src/gui/widgets/toggle_panel.cpp

@@ -102,7 +102,7 @@ SDL_Rect ttoggle_panel::get_client_rect() const
 		boost::dynamic_pointer_cast<const ttoggle_panel_definition::tresolution>(config());
 	assert(conf);
 
-	SDL_Rect result = get_rect();
+	SDL_Rect result = get_rectangle();
 	result.x += conf->left_border;
 	result.y += conf->top_border;
 	result.w -= conf->left_border + conf->right_border;

src/gui/widgets/tree_view.cpp

@@ -131,7 +131,7 @@ void ttree_view::resize_content(
 		need_layout_ = true;
 		// If the content grows assume it "overwrites" the old content.
 		if(width_modification < 0 || height_modification < 0) {
-			set_dirty();
+			set_dirty(true);
 		}
 		DBG_GUI_L << LOG_HEADER << " succeeded.\n";
 	} else {
@@ -147,7 +147,7 @@ void ttree_view::layout_children(const bool force)
 		root_node_->place(indention_step_size_
 			, get_origin()
 			, content_grid()->get_size().x);
-		root_node_->set_visible_area(content_visible_area_);
+		root_node_->set_visible_rectangle(content_visible_area_);
 
 		need_layout_ = false;
 	}

src/gui/widgets/tree_view_node.cpp

@@ -62,7 +62,7 @@ ttree_view_node::ttree_view_node(const std::string& id
 						, false);
 
 				if(icon_) {
-					icon_->set_visible(twidget::HIDDEN);
+					icon_->set_visible(twidget::tvisible::hidden);
 					icon_->connect_signal<event::LEFT_BUTTON_CLICK>(
 							boost::bind(&ttree_view_node::
 								signal_handler_left_button_click
@@ -71,7 +71,7 @@ ttree_view_node::ttree_view_node(const std::string& id
 				}
 
 				if(parent_node_ && parent_node_->icon_) {
-					parent_node_->icon_->set_visible(twidget::VISIBLE);
+					parent_node_->icon_->set_visible(twidget::tvisible::visible);
 				}
 
 				twidget& widget = find_widget<twidget>(
@@ -329,7 +329,7 @@ tpoint ttree_view_node::get_current_size() const
 
 		const ttree_view_node& node = *itor;
 
-		if(node.grid_.get_visible() == twidget::INVISIBLE) {
+		if(node.grid_.get_visible() == twidget::tvisible::invisible) {
 			continue;
 		}
 
@@ -363,7 +363,7 @@ tpoint ttree_view_node::get_unfolded_size() const
 
 		const ttree_view_node& node = *itor;
 
-		if(node.grid_.get_visible() == twidget::INVISIBLE) {
+		if(node.grid_.get_visible() == twidget::tvisible::invisible) {
 			continue;
 		}
 
@@ -400,7 +400,7 @@ tpoint ttree_view_node::calculate_best_size(const int indention_level
 
 		const ttree_view_node& node = *itor;
 
-		if(node.grid_.get_visible() == twidget::INVISIBLE) {
+		if(node.grid_.get_visible() == twidget::tvisible::invisible) {
 			continue;
 		}
 
@@ -468,11 +468,11 @@ unsigned ttree_view_node::place(
 	return origin.y - offset;
 }
 
-void ttree_view_node::set_visible_area(const SDL_Rect& area)
+void ttree_view_node::set_visible_rectangle(const SDL_Rect& rectangle)
 {
 	log_scope2(log_gui_layout, LOG_SCOPE_HEADER);
-	DBG_GUI_L << LOG_HEADER << " area " << area << ".\n";
+	DBG_GUI_L << LOG_HEADER << " rectangle " << rectangle << ".\n";
-	grid_.set_visible_area(area);
+	grid_.set_visible_rectangle(rectangle);
 
 	if(is_folded()) {
 		DBG_GUI_L << LOG_HEADER << " folded node done.\n";
@@ -480,7 +480,7 @@ void ttree_view_node::set_visible_area(const SDL_Rect& area)
 	}
 
 	FOREACH(AUTO& node, children_) {
-		node.set_visible_area(area);
+		node.set_visible_rectangle(rectangle);
 	}
 }
 

src/gui/widgets/tree_view_node.hpp

@@ -248,7 +248,8 @@ private:
 			, tpoint origin
 			, unsigned width);
 
-	void set_visible_area(const SDL_Rect& area);
+	/** See @ref twidget::set_visible_rectangle. */
+	virtual void set_visible_rectangle(const SDL_Rect& rectangle) OVERRIDE;
 
 	void impl_draw_children(surface& frame_buffer);
 	void impl_draw_children(surface& frame_buffer, int x_offset, int y_offset);

src/gui/widgets/viewport.cpp

@@ -121,12 +121,12 @@ void tviewport::place(const tpoint& origin, const tpoint& size)
 	widget_.place(tpoint(0, 0), widget_.get_best_size());
 }
 
-void tviewport::layout_init(const bool full_initialization)
+void tviewport::layout_initialise(const bool full_initialisation)
 {
-	twidget::layout_init(full_initialization);
+	twidget::layout_initialise(full_initialisation);
 
-	if(widget_.get_visible() != twidget::INVISIBLE) {
+	if(widget_.get_visible() != twidget::tvisible::invisible) {
-		widget_.layout_init(full_initialization);
+		widget_.layout_initialise(full_initialisation);
 	}
 }
 
@@ -138,7 +138,7 @@ void tviewport::impl_draw_children(
 	x_offset += get_x();
 	y_offset += get_y();
 
-	if(widget_.get_visible() != twidget::INVISIBLE) {
+	if(widget_.get_visible() != twidget::tvisible::invisible) {
 		widget_.draw_background(frame_buffer, x_offset, y_offset);
 		widget_.draw_children(frame_buffer, x_offset, y_offset);
 		widget_.draw_foreground(frame_buffer, x_offset, y_offset);

src/gui/widgets/viewport.hpp

@@ -53,8 +53,8 @@ public:
 	/** Inherited from twidget. */
 	void place(const tpoint& origin, const tpoint& size);
 
-	/** Inherited from twidget. */
+	/** See @ref twidget::layout_initialise. */
-	void layout_init(const bool full_initialization);
+	virtual void layout_initialise(const bool full_initialisation) OVERRIDE;
 
 	/** Inherited from twidget. */
 	void impl_draw_children(surface& frame_buffer, int x_offset, int y_offset);

src/gui/widgets/widget.cpp

@@ -22,25 +22,27 @@
 
 namespace gui2 {
 
+	/***** ***** ***** Constructor and destructor. ***** ***** *****/
+
 twidget::twidget()
 	: id_("")
 	, parent_(NULL)
 	, x_(-1)
 	, y_(-1)
-	, w_(0)
+	, width_(0)
-	, h_(0)
+	, height_(0)
-	, dirty_(true)
-	, visible_(VISIBLE)
-	, drawing_action_(DRAWN)
-	, clip_rect_()
 	, layout_size_(tpoint(0,0))
-	, linked_group_()
-#ifndef LOW_MEM
-	, debug_border_mode_(0)
-	, debug_border_color_(0)
-#endif
 #ifdef DEBUG_WINDOW_LAYOUT_GRAPHS
 	, last_best_size_(tpoint(0,0))
+#endif
+	, linked_group_()
+	, dirty_(true)
+	, visible_(tvisible::visible)
+	, redraw_action_(tredraw_action::full)
+	, clipping_rectangle_()
+#ifndef LOW_MEM
+	, debug_border_mode_(0)
+	, debug_border_colour_(0)
 #endif
 {
 	DBG_GUI_LF << "widget create: " << static_cast<void*>(this) << "\n";
@@ -51,20 +53,20 @@ twidget::twidget(const tbuilder_widget& builder)
 	, parent_(NULL)
 	, x_(-1)
 	, y_(-1)
-	, w_(0)
+	, width_(0)
-	, h_(0)
+	, height_(0)
-	, dirty_(true)
-	, visible_(VISIBLE)
-	, drawing_action_(DRAWN)
-	, clip_rect_()
 	, layout_size_(tpoint(0,0))
-	, linked_group_(builder.linked_group)
-#ifndef LOW_MEM
-	, debug_border_mode_(builder.debug_border_mode)
-	, debug_border_color_(builder.debug_border_color)
-#endif
 #ifdef DEBUG_WINDOW_LAYOUT_GRAPHS
 	, last_best_size_(tpoint(0,0))
+#endif
+	, linked_group_(builder.linked_group)
+	, dirty_(true)
+	, visible_(tvisible::visible)
+	, redraw_action_(tredraw_action::full)
+	, clipping_rectangle_()
+#ifndef LOW_MEM
+	, debug_border_mode_(builder.debug_border_mode)
+	, debug_border_colour_(builder.debug_border_color)
 #endif
 {
 	DBG_GUI_LF << "widget create: " << static_cast<void*>(this) << "\n";
@@ -72,8 +74,9 @@ twidget::twidget(const tbuilder_widget& builder)
 
 twidget::~twidget()
 {
-	DBG_GUI_LF << "widget destroy: " << static_cast<void*>(this)
+	DBG_GUI_LF
-		<< " (id: " << id_ << ")\n";
+			<< "widget destroy: " << static_cast<void*>(this)
+			<< " (id: " << id_ << ")\n";
 
 	twidget* p = parent();
 	while(p) {
@@ -88,104 +91,28 @@ twidget::~twidget()
 	}
 }
 
+	/***** ***** ***** ***** ID functions. ***** ***** ***** *****/
+
 void twidget::set_id(const std::string& id)
 {
-	DBG_GUI_LF << "set id of " << static_cast<void*>(this)
+	DBG_GUI_LF
-		<< " to '" << id << "' "
+			<< "set id of " << static_cast<void*>(this)
-		<< "(was '" << id_ << "'). Widget type: " <<
+			<< " to '" << id << "' "
-		(dynamic_cast<tcontrol*>(this) ?
+			<< "(was '" << id_ << "'). Widget type: "
-			dynamic_cast<tcontrol*>(this)->get_control_type()
+			<< (dynamic_cast<tcontrol*>(this)
-			: typeid(twidget).name())
+				?  dynamic_cast<tcontrol*>(this)->get_control_type()
-		<< "\n";
+				: typeid(twidget).name())
+			<< "\n";
+
 	id_ = id;
 }
 
-
+const std::string& twidget::id() const
-void twidget::layout_init(const bool /*full_initialization*/)
 {
-	assert(visible_ != INVISIBLE);
+	return id_;
-	assert(get_window());
-
-	layout_size_ = tpoint(0,0);
-	if(!linked_group_.empty()) {
-		get_window()->add_linked_widget(linked_group_, this);
-	}
 }
 
-tpoint twidget::get_best_size() const
+	/***** ***** ***** ***** Parent functions ***** ***** ***** *****/
-{
-	assert(visible_ != INVISIBLE);
-
-	tpoint result = layout_size_;
-	if(result == tpoint(0, 0)) {
-		result = calculate_best_size();
-	}
-
-#ifdef DEBUG_WINDOW_LAYOUT_GRAPHS
-	last_best_size_ = result;
-#endif
-	return result;
-}
-
-void twidget::place(const tpoint& origin, const tpoint& size)
-{
-	assert(size.x >= 0);
-	assert(size.y >= 0);
-
-	x_ = origin.x;
-	y_ = origin.y;
-	w_ = size.x;
-	h_ = size.y;
-
-#if 0
-	std::cerr << "Id " << id()
-		<< " rect " << get_rect()
-		<< " parent "
-			<< (parent ? parent->get_x() : 0)
-			<< ','
-			<< (parent ? parent->get_y() : 0)
-		<< " screen origin " << x_ << ',' << y_
-		<< ".\n";
-#endif
-
-	set_dirty();
-}
-
-void twidget::set_size(const tpoint& size)
-{
-	assert(size.x >= 0);
-	assert(size.y >= 0);
-
-	w_ = size.x;
-	h_ = size.y;
-
-	set_dirty();
-}
-
-twidget* twidget::find_at(const tpoint& coordinate,
-		const bool must_be_active)
-{
-	return is_at(coordinate, must_be_active) ? this : NULL;
-}
-
-const twidget* twidget::find_at(const tpoint& coordinate,
-		const bool must_be_active) const
-{
-	return is_at(coordinate, must_be_active) ? this : NULL;
-}
-
-SDL_Rect twidget::get_dirty_rect() const
-{
-	return drawing_action_ == DRAWN
-			? get_rect()
-			: clip_rect_;
-}
-
-void twidget::move(const int x_offset, const int y_offset)
-{
-	x_ += x_offset;
-	y_ += y_offset;
-}
 
 twindow* twidget::get_window()
 {
@@ -197,7 +124,7 @@ twindow* twidget::get_window()
 		result = result->parent_;
 	}
 
-	// on error dynamic_cast return 0 which is what we want.
+	// on error dynamic_cast returns NULL which is what we want.
 	return dynamic_cast<twindow*>(result);
 }
 
@@ -211,7 +138,7 @@ const twindow* twidget::get_window() const
 		result = result->parent_;
 	}
 
-	// on error dynamic_cast return 0 which is what we want.
+	// on error dynamic_cast returns NULL which is what we want.
 	return dynamic_cast<const twindow*>(result);
 }
 
@@ -221,16 +148,285 @@ tdialog* twidget::dialog()
 	return window ? window->dialog() : NULL;
 }
 
+void twidget::set_parent(twidget* parent)
+{
+	parent_ = parent;
+}
+
+twidget* twidget::parent()
+{
+	return parent_;
+}
+
+	/***** ***** ***** ***** Size and layout functions. ***** ***** ***** *****/
+
+void twidget::layout_initialise(const bool /*full_initialisation*/)
+{
+	assert(visible_ != tvisible::invisible);
+	assert(get_window());
+
+	layout_size_ = tpoint(0,0);
+	if(!linked_group_.empty()) {
+		get_window()->add_linked_widget(linked_group_, this);
+	}
+}
+
+void twidget::demand_reduce_width(const unsigned /*maximum_width*/)
+{
+	/* DO NOTHING */
+}
+
+void twidget::request_reduce_height(const unsigned /*maximum_height*/)
+{
+	/* DO NOTHING */
+}
+
+void twidget::demand_reduce_height(const unsigned /*maximum_height*/)
+{
+	/* DO NOTHING */
+}
+
+tpoint twidget::get_best_size() const
+{
+	assert(visible_ != tvisible::invisible);
+
+	tpoint result = layout_size_;
+	if(result == tpoint(0, 0)) {
+		result = calculate_best_size();
+	}
+
+#ifdef DEBUG_WINDOW_LAYOUT_GRAPHS
+	last_best_size_ = result;
+#endif
+
+	return result;
+}
+
+bool twidget::can_wrap() const
+{
+	return false;
+}
+
+void twidget::set_origin(const tpoint& origin)
+{
+	x_ = origin.x;
+	y_ = origin.y;
+}
+
+void twidget::set_size(const tpoint& size)
+{
+	assert(size.x >= 0);
+	assert(size.y >= 0);
+
+	width_ = size.x;
+	height_ = size.y;
+
+	set_dirty(true);
+}
+
+void twidget::place(const tpoint& origin, const tpoint& size)
+{
+	assert(size.x >= 0);
+	assert(size.y >= 0);
+
+	x_ = origin.x;
+	y_ = origin.y;
+	width_ = size.x;
+	height_ = size.y;
+
+#if 0
+	std::cerr
+			<< "Id " << id()
+			<< " rect " << get_rectangle()
+			<< " parent "
+			<< (parent ? parent->get_x() : 0)
+			<< ','
+			<< (parent ? parent->get_y() : 0)
+			<< " screen origin " << x_ << ',' << y_
+			<< ".\n";
+#endif
+
+	set_dirty(true);
+}
+
+void twidget::move(const int x_offset, const int y_offset)
+{
+	x_ += x_offset;
+	y_ += y_offset;
+}
+
+void twidget::layout_children()
+{
+	/* DO NOTHING */
+}
+
+tpoint twidget::get_origin() const
+{
+	return tpoint(x_, y_);
+}
+
+tpoint twidget::get_size() const
+{
+	return tpoint(width_, height_);
+}
+
+SDL_Rect twidget::get_rectangle() const
+{
+	return create_rect(get_origin(), get_size());
+}
+
+int twidget::get_x() const
+{
+	return x_;
+}
+
+int twidget::get_y() const
+{
+	return y_;
+}
+
+unsigned twidget::get_width() const
+{
+	return width_;
+}
+
+unsigned twidget::get_height() const
+{
+	return height_;
+}
+
+void twidget::set_layout_size(const tpoint& size)
+{
+	layout_size_ = size;
+}
+
+const tpoint& twidget::layout_size() const
+{
+	return layout_size_;
+}
+
+void twidget::set_linked_group(const std::string& linked_group)
+{
+	linked_group_ = linked_group;
+}
+
+	/***** ***** ***** ***** Drawing functions. ***** ***** ***** *****/
+
+SDL_Rect twidget::calculate_blitting_rectangle(
+		  const int x_offset
+		, const int y_offset)
+{
+	SDL_Rect result = get_rectangle();
+	result.x += x_offset;
+	result.y += y_offset;
+	return result;
+}
+
+SDL_Rect twidget::calculate_clipping_rectangle(
+		  const int x_offset
+		, const int y_offset)
+{
+	SDL_Rect result = clipping_rectangle_;
+	result.x += x_offset;
+	result.y += y_offset;
+	return result;
+}
+
+void twidget::draw_background(surface& frame_buffer, int x_offset, int y_offset)
+{
+	assert(visible_ == tvisible::visible);
+
+	if(redraw_action_ == tredraw_action::partly) {
+		const SDL_Rect clipping_rectangle
+				= calculate_clipping_rectangle(x_offset, y_offset);
+
+		clip_rect_setter clip(frame_buffer, &clipping_rectangle);
+		draw_debug_border(frame_buffer, x_offset, y_offset);
+		impl_draw_background(frame_buffer, x_offset, y_offset);
+	} else {
+		draw_debug_border(frame_buffer, x_offset, y_offset);
+		impl_draw_background(frame_buffer, x_offset, y_offset);
+	}
+}
+
+void twidget::draw_background(surface& frame_buffer)
+{
+	assert(visible_ == tvisible::visible);
+
+	if(redraw_action_ == tredraw_action::partly) {
+		clip_rect_setter clip(frame_buffer, &clipping_rectangle_);
+		draw_debug_border(frame_buffer);
+		impl_draw_background(frame_buffer);
+	} else {
+		draw_debug_border(frame_buffer);
+		impl_draw_background(frame_buffer);
+	}
+}
+
+void twidget::draw_children(surface& frame_buffer, int x_offset, int y_offset)
+{
+	assert(visible_ == tvisible::visible);
+
+	if(redraw_action_ == tredraw_action::partly) {
+		const SDL_Rect clipping_rectangle
+				= calculate_clipping_rectangle(x_offset, y_offset);
+
+		clip_rect_setter clip(frame_buffer, &clipping_rectangle);
+		impl_draw_children(frame_buffer, x_offset, y_offset);
+	} else {
+		impl_draw_children(frame_buffer, x_offset, y_offset);
+	}
+}
+
+void twidget::draw_children(surface& frame_buffer)
+{
+	assert(visible_ == tvisible::visible);
+
+	if(redraw_action_ == tredraw_action::partly) {
+		clip_rect_setter clip(frame_buffer, &clipping_rectangle_);
+		impl_draw_children(frame_buffer);
+	} else {
+		impl_draw_children(frame_buffer);
+	}
+}
+
+void twidget::draw_foreground(surface& frame_buffer, int x_offset, int y_offset)
+{
+	assert(visible_ == tvisible::visible);
+
+	if(redraw_action_ == tredraw_action::partly) {
+		const SDL_Rect clipping_rectangle
+				= calculate_clipping_rectangle(x_offset, y_offset);
+
+		clip_rect_setter clip(frame_buffer, &clipping_rectangle);
+		impl_draw_foreground(frame_buffer, x_offset, y_offset);
+	} else {
+		impl_draw_foreground(frame_buffer, x_offset, y_offset);
+	}
+}
+
+void twidget::draw_foreground(surface& frame_buffer)
+{
+	assert(visible_ == tvisible::visible);
+
+	if(redraw_action_ == tredraw_action::partly) {
+		clip_rect_setter clip(frame_buffer, &clipping_rectangle_);
+		impl_draw_foreground(frame_buffer);
+	} else {
+		impl_draw_foreground(frame_buffer);
+	}
+}
+
 void twidget::populate_dirty_list(twindow& caller,
 		std::vector<twidget*>& call_stack)
 {
 	assert(call_stack.empty() || call_stack.back() != this);
 
-	if(visible_ != VISIBLE) {
+	if(visible_ != tvisible::visible) {
 		return;
 	}
 
-	if(get_drawing_action() == NOT_DRAWN) {
+	if(get_drawing_action() == tredraw_action::none) {
 		return;
 	}
 
@@ -243,14 +439,52 @@ void twidget::populate_dirty_list(twindow& caller,
 	}
 }
 
-void twidget::set_visible(const tvisible visible)
+void twidget::child_populate_dirty_list(
+			  twindow& /*caller*/
+			, const std::vector<twidget*>& /*call_stack*/)
+{
+	/* DO NOTHING */
+}
+
+SDL_Rect twidget::get_dirty_rectangle() const
+{
+	return redraw_action_ == tredraw_action::full
+			? get_rectangle()
+			: clipping_rectangle_;
+}
+
+void twidget::set_visible_rectangle(const SDL_Rect& rectangle)
+{
+	clipping_rectangle_ = intersect_rects(rectangle, get_rectangle());
+
+	if(clipping_rectangle_ == get_rectangle()) {
+		redraw_action_ = tredraw_action::full;
+	} else if(clipping_rectangle_ == empty_rect) {
+		redraw_action_ = tredraw_action::none;
+	} else {
+		redraw_action_ = tredraw_action::partly;
+	}
+}
+
+void twidget::set_dirty(const bool dirty)
+{
+	dirty_ = dirty;
+}
+
+bool twidget::get_dirty() const
+{
+	return dirty_;
+}
+
+void twidget::set_visible(const tvisible::scoped_enum visible)
 {
 	if(visible == visible_) {
 		return;
 	}
 
 	// Switching to or from invisible should invalidate the layout.
-	const bool need_resize = visible_ == INVISIBLE || visible == INVISIBLE;
+	const bool need_resize
+			= visible_ == tvisible::invisible || visible == tvisible::invisible;
 	visible_ = visible;
 
 	if(need_resize) {
@@ -264,152 +498,58 @@ void twidget::set_visible(const tvisible visible)
 			}
 		}
 	} else {
-		set_dirty();
+		set_dirty(true);
 	}
 }
 
-twidget::tdrawing_action twidget::get_drawing_action() const
+twidget::tvisible::scoped_enum twidget::get_visible() const
 {
-	return (w_ == 0 || h_ == 0)
+	return visible_;
-		? NOT_DRAWN
-		: drawing_action_;
 }
 
-void twidget::set_visible_area(const SDL_Rect& area)
+twidget::tredraw_action::scoped_enum twidget::get_drawing_action() const
 {
-	clip_rect_ = intersect_rects(area, get_rect());
+	return (width_ == 0 || height_ == 0)
-
+			? tredraw_action::none
-	if(clip_rect_ == get_rect()) {
+			: redraw_action_;
-		drawing_action_ = DRAWN;
-	} else if(clip_rect_ == empty_rect) {
-		drawing_action_ = NOT_DRAWN;
-	} else {
-		drawing_action_ = PARTLY_DRAWN;
-	}
-}
-
-SDL_Rect twidget::calculate_blitting_rectangle(
-		  const int x_offset
-		, const int y_offset)
-{
-	SDL_Rect result = get_rect();
-	result.x += x_offset;
-	result.y += y_offset;
-	return result;
-}
-
-SDL_Rect twidget::calculate_clipping_rectangle(
-		  const int x_offset
-		, const int y_offset)
-{
-	SDL_Rect result = clip_rect_;
-	result.x += x_offset;
-	result.y += y_offset;
-	return result;
-}
-
-void twidget::draw_background(surface& frame_buffer)
-{
-	assert(visible_ == VISIBLE);
-
-	if(drawing_action_ == PARTLY_DRAWN) {
-		clip_rect_setter clip(frame_buffer, &clip_rect_);
-		draw_debug_border(frame_buffer);
-		impl_draw_background(frame_buffer);
-	} else {
-		draw_debug_border(frame_buffer);
-		impl_draw_background(frame_buffer);
-	}
-}
-
-void twidget::draw_background(surface& frame_buffer, int x_offset, int y_offset)
-{
-	assert(visible_ == VISIBLE);
-
-	if(drawing_action_ == PARTLY_DRAWN) {
-		const SDL_Rect clipping_rectangle =
-				calculate_clipping_rectangle(x_offset, y_offset);
-
-		clip_rect_setter clip(frame_buffer, &clipping_rectangle);
-		draw_debug_border(frame_buffer, x_offset, y_offset);
-		impl_draw_background(frame_buffer, x_offset, y_offset);
-	} else {
-		draw_debug_border(frame_buffer, x_offset, y_offset);
-		impl_draw_background(frame_buffer, x_offset, y_offset);
-	}
-}
-
-void twidget::draw_children(surface& frame_buffer)
-{
-	assert(visible_ == VISIBLE);
-
-	if(drawing_action_ == PARTLY_DRAWN) {
-		clip_rect_setter clip(frame_buffer, &clip_rect_);
-		impl_draw_children(frame_buffer);
-	} else {
-		impl_draw_children(frame_buffer);
-	}
-}
-
-void twidget::draw_children(surface& frame_buffer, int x_offset, int y_offset)
-{
-	assert(visible_ == VISIBLE);
-
-	if(drawing_action_ == PARTLY_DRAWN) {
-		const SDL_Rect clipping_rectangle =
-				calculate_clipping_rectangle(x_offset, y_offset);
-
-		clip_rect_setter clip(frame_buffer, &clipping_rectangle);
-		impl_draw_children(frame_buffer, x_offset, y_offset);
-	} else {
-		impl_draw_children(frame_buffer, x_offset, y_offset);
-	}
-}
-
-void twidget::draw_foreground(surface& frame_buffer)
-{
-	assert(visible_ == VISIBLE);
-
-	if(drawing_action_ == PARTLY_DRAWN) {
-		clip_rect_setter clip(frame_buffer, &clip_rect_);
-		impl_draw_foreground(frame_buffer);
-	} else {
-		impl_draw_foreground(frame_buffer);
-	}
-}
-
-void twidget::draw_foreground(surface& frame_buffer, int x_offset, int y_offset)
-{
-	assert(visible_ == VISIBLE);
-
-	if(drawing_action_ == PARTLY_DRAWN) {
-		const SDL_Rect clipping_rectangle =
-				calculate_clipping_rectangle(x_offset, y_offset);
-
-		clip_rect_setter clip(frame_buffer, &clipping_rectangle);
-		impl_draw_foreground(frame_buffer, x_offset, y_offset);
-	} else {
-		impl_draw_foreground(frame_buffer, x_offset, y_offset);
-	}
 }
 
 #ifndef LOW_MEM
+
+void twidget::set_debug_border_mode(const unsigned debug_border_mode)
+{
+	debug_border_mode_ = debug_border_mode;
+}
+
+void twidget::set_debug_border_colour(const unsigned debug_border_colour)
+{
+	debug_border_colour_ = debug_border_colour;
+}
+
 void twidget::draw_debug_border(surface& frame_buffer)
 {
-	SDL_Rect r = drawing_action_ == PARTLY_DRAWN
+	SDL_Rect r = redraw_action_ == tredraw_action::partly
-		? clip_rect_
+			? clipping_rectangle_
-		: get_rect();
+			: get_rectangle();
+
 	switch(debug_border_mode_) {
 		case 0:
 			/* DO NOTHING */
 			break;
 		case 1:
-			draw_rectangle(r.x, r.y, r.w, r.h
+			draw_rectangle(
-					, debug_border_color_, frame_buffer);
+					  r.x
+					, r.y
+					, r.w
+					, r.h
+					, debug_border_colour_
+					, frame_buffer);
 			break;
+
 		case 2:
-			sdl_fill_rect(frame_buffer, &r, debug_border_color_);
+			sdl_fill_rect(frame_buffer, &r, debug_border_colour_);
 			break;
+
 		default:
 			assert(false);
 	}
@@ -420,7 +560,7 @@ void twidget::draw_debug_border(
 		, int x_offset
 		, int y_offset)
 {
-	SDL_Rect r = drawing_action_ == PARTLY_DRAWN
+	SDL_Rect r = redraw_action_ == tredraw_action::partly
 		? calculate_clipping_rectangle(x_offset, y_offset)
 		: calculate_blitting_rectangle(x_offset, y_offset);
 
@@ -428,29 +568,78 @@ void twidget::draw_debug_border(
 		case 0:
 			/* DO NOTHING */
 			break;
+
 		case 1:
-			draw_rectangle(r.x, r.y, r.w, r.h
+			draw_rectangle(
-					, debug_border_color_, frame_buffer);
+					  r.x
+					, r.y
+					, r.w
+					, r.h
+					, debug_border_colour_
+					, frame_buffer);
 			break;
+
 		case 2:
-			sdl_fill_rect(frame_buffer, &r, debug_border_color_);
+			sdl_fill_rect(frame_buffer, &r, debug_border_colour_);
 			break;
+
 		default:
 			assert(false);
 	}
 }
+
 #endif
 
+	/***** ***** ***** ***** Query functions ***** ***** ***** *****/
+
+twidget* twidget::find_at(
+		  const tpoint& coordinate
+		, const bool must_be_active)
+{
+	return is_at(coordinate, must_be_active) ? this : NULL;
+}
+
+const twidget* twidget::find_at(const tpoint& coordinate,
+		const bool must_be_active) const
+{
+	return is_at(coordinate, must_be_active) ? this : NULL;
+}
+
+twidget* twidget::find(
+		  const std::string& id
+		, const bool /*must_be_active*/)
+{
+	return id_ == id ? this : NULL;
+}
+
+const twidget* twidget::find(
+		  const std::string& id
+		, const bool /*must_be_active*/) const
+{
+	return id_ == id ? this : NULL;
+}
+
+bool twidget::has_widget(const twidget* widget) const
+{
+	return widget == this;
+}
+
+bool twidget::is_at(const tpoint& coordinate) const
+{
+	return is_at(coordinate, true);
+}
+
 bool twidget::is_at(const tpoint& coordinate, const bool must_be_active) const
 {
-	if(visible_ == INVISIBLE
+	if(visible_ == tvisible::invisible
-			|| (visible_ == HIDDEN && must_be_active)) {
+			|| (visible_ == tvisible::hidden && must_be_active)) {
 		return false;
 	}
 
 	return coordinate.x >= x_
-			&& coordinate.x < (x_ + static_cast<int>(w_))
+			&& coordinate.x < (x_ + static_cast<int>(width_))
 			&& coordinate.y >= y_
-			&& coordinate.y < (y_ + static_cast<int>(h_)) ? true : false;
+			&& coordinate.y < (y_ + static_cast<int>(height_));
 }
+
 } // namespace gui2

src/gui/widgets/window.cpp

@@ -675,9 +675,9 @@ int twindow::show(const bool restore, const unsigned auto_close_timeout)
 
 		// restore area
 		if(restore) {
-			SDL_Rect rect = get_rect();
+			SDL_Rect rect = get_rectangle();
 			sdl_blit(restorer_, 0, video_.getSurface(), &rect);
-			update_rect(get_rect());
+			update_rect(get_rectangle());
 			font::undraw_floating_labels(video_.getSurface());
 		}
 		throw;
@@ -687,9 +687,9 @@ int twindow::show(const bool restore, const unsigned auto_close_timeout)
 
 	// restore area
 	if(restore) {
-		SDL_Rect rect = get_rect();
+		SDL_Rect rect = get_rectangle();
 		sdl_blit(restorer_, 0, video_.getSurface(), &rect);
-		update_rect(get_rect());
+		update_rect(get_rectangle());
 		font::undraw_floating_labels(video_.getSurface());
 	}
 
@@ -712,7 +712,7 @@ void twindow::draw()
 		// since all will be redrawn when needed with dirty rects. Since that
 		// doesn't work yet we need to undraw the window.
 		if(restorer_) {
-			SDL_Rect rect = get_rect();
+			SDL_Rect rect = get_rectangle();
 			sdl_blit(restorer_, 0, frame_buffer, &rect);
 			// Since the old area might be bigger as the new one, invalidate
 			// it.
@@ -722,7 +722,7 @@ void twindow::draw()
 		layout();
 
 		// Get new surface for restoring
-		SDL_Rect rect = get_rect();
+		SDL_Rect rect = get_rectangle();
 		// We want the labels underneath the window so draw them and use them
 		// as restore point.
 		font::draw_floating_labels(frame_buffer);
@@ -773,7 +773,7 @@ void twindow::draw()
 
 		const SDL_Rect dirty_rect = new_widgets
 				? screen_area()
-				: item.back()->get_dirty_rect();
+				: item.back()->get_dirty_rectangle();
 
 // For testing we disable the clipping rect and force the entire screen to
 // update. This way an item rendered at the wrong place is directly visible.
@@ -801,16 +801,17 @@ void twindow::draw()
 		 *
 		 * Before drawing there needs to be determined whether a dirty widget
 		 * really needs to be redrawn. If the widget doesn't need to be
-		 * redrawing either being not VISIBLE or has status NOT_DRAWN. If
+		 * redrawing either being not tvisible::visible or has status
-		 * it's not drawn it's still set not dirty to avoid it keep getting
+		 * twidget::tredraw_action::none. If it's not drawn it's still set not
-		 * on the dirty list.
+		 * dirty to avoid it keep getting on the dirty list.
 		 */
 
 		for(std::vector<twidget*>::iterator itor = item.begin();
 				itor != item.end(); ++itor) {
 
-			if((**itor).get_visible() != twidget::VISIBLE
+			if((**itor).get_visible() != twidget::tvisible::visible
-					|| (**itor).get_drawing_action() == twidget::NOT_DRAWN) {
+					|| (**itor).get_drawing_action()
+						== twidget::tredraw_action::none) {
 
 				for(std::vector<twidget*>::iterator citor = itor;
 						citor != item.end(); ++citor) {
@@ -824,7 +825,7 @@ void twindow::draw()
 		}
 
 		// Restore.
-		SDL_Rect rect = get_rect();
+		SDL_Rect rect = get_rectangle();
 		sdl_blit(restorer_, 0, frame_buffer, &rect);
 
 		/**
@@ -890,14 +891,14 @@ void twindow::draw()
 	populate_dirty_list(*this, call_stack);
 	assert(dirty_list_.empty());
 
-	SDL_Rect rect = get_rect();
+	SDL_Rect rect = get_rectangle();
 	update_rect(rect);
 }
 
 void twindow::undraw()
 {
 	if(restorer_) {
-		SDL_Rect rect = get_rect();
+		SDL_Rect rect = get_rectangle();
 		sdl_blit(restorer_, 0, video_.getSurface(), &rect);
 		// Since the old area might be bigger as the new one, invalidate
 		// it.
@@ -999,12 +1000,12 @@ void twindow::layout()
 	if((click_dismiss_button
 			= find_widget<tbutton>(this, "click_dismiss", false, false))) {
 
-		click_dismiss_button->set_visible(twidget::INVISIBLE);
+		click_dismiss_button->set_visible(twidget::tvisible::invisible);
 	}
 	if(click_dismiss_) {
 		tbutton* button = find_widget<tbutton>(this, "ok", false, false);
 		if(button) {
-			button->set_visible(twidget::INVISIBLE);
+			button->set_visible(twidget::tvisible::invisible);
 			click_dismiss_button = button;
 		}
 		VALIDATE(click_dismiss_button
@@ -1012,8 +1013,8 @@ void twindow::layout()
 	}
 
 	/***** Layout. *****/
-	layout_init(true);
+	layout_initialise(true);
-	generate_dot_file("layout_init", LAYOUT);
+	generate_dot_file("layout_initialise", LAYOUT);
 
 	layout_linked_widgets();
 
@@ -1040,7 +1041,7 @@ void twindow::layout()
 	/****** Validate click dismiss status. *****/
 	if(click_dismiss_ && disable_click_dismiss()) {
 		assert(click_dismiss_button);
-		click_dismiss_button->set_visible(twidget::VISIBLE);
+		click_dismiss_button->set_visible(twidget::tvisible::visible);
 
 		connect_signal_mouse_left_click(
 				  *click_dismiss_button
@@ -1050,8 +1051,8 @@ void twindow::layout()
 					, OK
 					, true));
 
-		layout_init(true);
+		layout_initialise(true);
-		generate_dot_file("layout_init", LAYOUT);
+		generate_dot_file("layout_initialise", LAYOUT);
 
 		layout_linked_widgets();
 
@@ -1312,7 +1313,7 @@ void twindow_implementation::layout(twindow& window,
 		DBG_GUI_L << LOG_IMPL_HEADER
 				<< " Status: Width has been modified, rerun.\n";
 
-		window.layout_init(false);
+		window.layout_initialise(false);
 		window.layout_linked_widgets();
 		layout(window, maximum_width, maximum_height);
 		return;
@@ -1499,13 +1500,14 @@ void twindow::signal_handler_request_placement(
  *   layout property must be set by the engine after validation.
  *
  * - All visible grid cells; A grid cell is visible when the widget inside
- *   of it doesn't have the state INVISIBLE. Widgets which are HIDDEN are
+ *   of it doesn't have the state tvisible::invisible. Widgets which have the
- *   sized properly since when they become VISIBLE the layout shouldn't be
+ *   state @ref tvisible::hidden are sized properly since when they become
- *   invalidated. A grid cell that's invisible has size 0,0.
+ *   @ref tvisible::visible the layout shouldn't be invalidated. A grid cell
+ *   that's invisible has size 0,0.
  *
  * - All resizable grid cells; A grid cell is resizable under the following
  *   conditions:
- *   - The widget is VISIBLE.
+ *   - The widget is tvisible::visible.
  *   - The widget is not in a shared size group.
  *
  * There are two layout algorithms with a different purpose.
@@ -1524,7 +1526,7 @@ void twindow::signal_handler_request_placement(
  * Here is the algorithm used to layout the window:
  *
  * - Perform a full initialization
- *   (@ref gui2::twidget::layout_init (full_initialization = true)):
+ *   (@ref gui2::twidget::layout_initialise (full_initialisation = true)):
  *   - Clear the internal best size cache for all widgets.
  *   - For widgets with scrollbars hide them unless the
  *     @ref gui2::tscrollbar_container::tscrollbar_mode "scrollbar_mode" is
@@ -1616,7 +1618,7 @@ void twindow::signal_handler_request_placement(
  *
  * - Relayout:
  *   - Initialize all widgets
- *     (@ref gui2::twidget::layout_init (full_initialization = false))
+ *     (@ref gui2::twidget::layout_initialise (full_initialisation = false))
  *   - Handle shared sizes, since the reinitialization resets that state.
  *   - Goto start layout loop.
  *

src/gui/widgets/window.hpp

@@ -410,7 +410,7 @@ public:
 	void set_variable(const std::string& key, const variant& value)
 	{
 		variables_.add(key, value);
-		set_dirty();
+		set_dirty(true);
 	}
 
 private: