make loadingscreen more responsive to user input.

We now create a new thread that does the actual loading while the main
thread handles user input (and drawing of the loadingscreen ). That way
wesnoth can still react on user input such as close game requests while
reading the config files.

src/game_config_manager.cpp

@@ -89,7 +89,7 @@ bool game_config_manager::init_game_config(FORCE_RELOAD_CONFIG force_reload)
 	game_config::scoped_preproc_define title_screen("TITLE_SCREEN",
 		!cmdline_opts_.multiplayer && !cmdline_opts_.test && !jump_to_editor_);
 
-	load_game_config(force_reload);
+	load_game_config_with_loadscreen(force_reload);
 
 	game_config::load_config(game_config_.child("game_config"));
 
@@ -119,10 +119,17 @@ bool map_includes(const preproc_map& general, const preproc_map& special)
 }
 } // end anonymous namespace
 
-void game_config_manager::load_game_config(FORCE_RELOAD_CONFIG force_reload,
+void game_config_manager::load_game_config_with_loadscreen(FORCE_RELOAD_CONFIG force_reload,
 	game_classification const* classification)
 {
-	// Make sure that 'debug mode' symbol is set
+	gui2::tloadscreen::display(video_, [=]() {
+		load_game_config(force_reload, classification);
+	});
+}
+void game_config_manager::load_game_config(FORCE_RELOAD_CONFIG force_reload,
+	game_classification const* classification)
+	{
+		// Make sure that 'debug mode' symbol is set
 	// if command line parameter is selected
 	// also if we're in multiplayer and actual debug mode is disabled.
 	game_config::scoped_preproc_define debug_mode("DEBUG_MODE",
@@ -138,8 +145,6 @@ void game_config_manager::load_game_config(FORCE_RELOAD_CONFIG force_reload,
 		}
 	}
 
-	gui2::tloadscreen::display(video_);
-
 	// The loadscreen will erase the titlescreen.
 	// NOTE: even without loadscreen, needed after MP lobby.
 	try {
@@ -493,7 +498,7 @@ void game_config_manager::reload_changed_game_config()
 void game_config_manager::load_game_config_for_editor()
 {
 	game_config::scoped_preproc_define editor("EDITOR");
-	load_game_config(NO_FORCE_RELOAD);
+	load_game_config_with_loadscreen(NO_FORCE_RELOAD);
 }
 
 void game_config_manager::load_game_config_for_game(
@@ -529,7 +534,7 @@ void game_config_manager::load_game_config_for_game(
 	}
 
 	try{
-		load_game_config(NO_FORCE_RELOAD, &classification);
+		load_game_config_with_loadscreen(NO_FORCE_RELOAD, &classification);
 	}
 	catch(game::error&) {
 		cache_.clear_defines();
@@ -541,7 +546,7 @@ void game_config_manager::load_game_config_for_game(
 			previous_defines.push_back(new_define);
 		}
 
-		load_game_config(NO_FORCE_RELOAD);
+		load_game_config_with_loadscreen(NO_FORCE_RELOAD);
 
 		throw;
 	}

src/game_config_manager.hpp

@@ -59,6 +59,9 @@ class game_config_manager
 	void load_game_config(FORCE_RELOAD_CONFIG force_reload,
 		game_classification const* classification = NULL);
 
+	void load_game_config_with_loadscreen(FORCE_RELOAD_CONFIG force_reload,
+		game_classification const* classification = NULL);
+
 	// load_game_config() helper functions.
 	void load_addons_cfg();
 	void set_multiplayer_hashes();

src/game_launcher.cpp

@@ -1011,9 +1011,9 @@ void game_launcher::launch_game(RELOAD_GAME_DATA reload)
 		return;
 	}
 
-	gui2::tloadscreen::display(video());
-	gui2::tloadscreen::progress("load data");
+	gui2::tloadscreen::display(video(), [=]() {
 
+	gui2::tloadscreen::progress("load data");
 	if(reload == RELOAD_DATA) {
 		try {
 			game_config_manager::get()->
@@ -1022,6 +1022,7 @@ void game_launcher::launch_game(RELOAD_GAME_DATA reload)
 			return;
 		}
 	}
+	});
 
 	try {
 		campaign_controller ccontroller(video(), state_, game_config_manager::get()->game_config(), game_config_manager::get()->terrain_types());

src/gui/dialogs/loadscreen.cpp

@@ -17,15 +17,21 @@
 #include "gui/dialogs/loadscreen.hpp"
 #include "gui/widgets/window.hpp"
 #include "gui/widgets/settings.hpp"
+#include "gui/core/timer.hpp"
 #include "video.hpp"
 
+#include <boost/bind.hpp>
+#include <boost/thread.hpp>
+
 namespace gui2
 {
 
 REGISTER_DIALOG(loadscreen)
 
 void tloadscreen::show(CVideo& video)
 {
+	tdialog::show(video);
+	return;
 	if(video.faked()) {
 		return;
 	}
@@ -53,14 +59,18 @@ twindow* tloadscreen::build_window(CVideo& video) const
 	return build(video, window_id());
 }
 
-void tloadscreen::pre_show(twindow& /*window*/)
+void tloadscreen::pre_show(twindow& window)
 {
+	worker_.reset(new boost::thread(work_));
+	timer_id_ = add_timer(100, boost::bind(&tloadscreen::timer_callback, this, boost::ref(window)), true);
 	// FIXME
 	cursor::setter cur(cursor::WAIT);
 }
 
 void tloadscreen::post_show(twindow& /*window*/)
 {
+	worker_.reset();
+	remove_timer(timer_id_);
 	cursor::setter cur(cursor::NORMAL);
 }
 
@@ -79,4 +89,12 @@ void tloadscreen::progress(const char* stage)
 
 tloadscreen* tloadscreen::current_load = NULL;
 
+void tloadscreen::timer_callback(twindow& window)
+{
+	if (!worker_ || worker_->timed_join(boost::posix_time::milliseconds(0))) {
+		window.close();
+
+	}
+}
+
 } // namespace gui2

src/gui/dialogs/loadscreen.hpp

@@ -15,8 +15,14 @@
 
 #include "gui/dialogs/dialog.hpp"
 
-class CVideo;
+#include <boost/function.hpp>
+#include <boost/scoped_ptr.hpp>
 
+class CVideo;
+namespace boost
+{
+	class thread;
+}
 namespace gui2
 {
 
@@ -25,22 +31,32 @@ class twindow;
 class tloadscreen : public tdialog
 {
 public:
-	tloadscreen()
+
+	tloadscreen(boost::function<void()> f)
 		: window_(NULL)
-		, previous_load(current_load)
 		, current_stage(NULL)
+		, timer_id_(0)
+		, work_(f)
+		, worker_()
 	{
 		current_load = this;
 	}
 
 	~tloadscreen()
 	{
 		close();
-		current_load = previous_load;
 	}
 
-	static void display(CVideo& video) {
-		tloadscreen().show(video);
+	static void display(CVideo& video, boost::function<void()> f) {
+		static bool already_shown = false;
+		if (already_shown) {
+			f();
+		}
+		else {
+			already_shown = true;
+			tloadscreen(f).show(video);
+			already_shown = false;
+		}
 	}
 
 	void show(CVideo& video);
@@ -56,20 +72,24 @@ class tloadscreen : public tdialog
 	void close();
 
 private:
+	size_t timer_id_;
+	boost::function<void()> work_;
+	boost::scoped_ptr<boost::thread> worker_;
 	twindow* window_;
 
 	twindow* build_window(CVideo& video) const;
 
 	virtual const std::string& window_id() const;
 
+	void timer_callback(twindow& window);
+
 	/** Inherited from tdialog. */
 	void pre_show(twindow& window);
 
 	/** Inherited from tdialog. */
 	void post_show(twindow& window);
 
 	static tloadscreen* current_load;
-	tloadscreen*const previous_load;
 	const char* current_stage;
 };
 

src/play_controller.cpp

@@ -224,7 +224,8 @@ struct throw_end_level
 
 void play_controller::init(CVideo& video, const config& level)
 {
-	gui2::tloadscreen::display(video);
+
+	gui2::tloadscreen::display(video, [this, &video, &level]() {
 	gui2::tloadscreen::progress("load level");
 
 	LOG_NG << "initializing game_state..." << (SDL_GetTicks() - ticks()) << std::endl;
@@ -307,6 +308,7 @@ void play_controller::init(CVideo& video, const config& level)
 	plugins_context_->set_callback("save_game", boost::bind(&play_controller::save_game_auto, this, boost::bind(get_str, _1, "filename" )), true);
 	plugins_context_->set_callback("save_replay", boost::bind(&play_controller::save_replay_auto, this, boost::bind(get_str, _1, "filename" )), true);
 	plugins_context_->set_callback("quit", throw_end_level(), false);
+	});
 }
 
 void play_controller::reset_gamestate(const config& level, int replay_pos)

src/wesnoth.cpp

@@ -640,13 +640,15 @@ static int do_gameloop(const std::vector<std::string>& args)
 	gui2::init();
 	const gui2::event::tmanager gui_event_manager;
 
-	gui2::tloadscreen::display(game->video());
 
 	game_config_manager config_manager(cmdline_opts, game->video(),
 	    game->jump_to_editor());
 
-	gui2::tloadscreen::progress("load config");
-	res = config_manager.init_game_config(game_config_manager::NO_FORCE_RELOAD);
+	gui2::tloadscreen::display(game->video(), [&]() {
+		gui2::tloadscreen::progress("load config");
+		res = config_manager.init_game_config(game_config_manager::NO_FORCE_RELOAD);
+	});
+
 	if(res == false) {
 		std::cerr << "could not initialize game config\n";
 		return 1;
@@ -851,9 +853,10 @@ static int do_gameloop(const std::vector<std::string>& args)
 			}
 			continue;
 		} else if(res == gui2::ttitle_screen::RELOAD_GAME_DATA) {
-			gui2::tloadscreen::display(game->video());
-			config_manager.reload_changed_game_config();
-			image::flush_cache();
+			gui2::tloadscreen::display(game->video(), [&]() {
+				config_manager.reload_changed_game_config();
+				image::flush_cache();
+			});
 			continue;
 		} else if(res == gui2::ttitle_screen::START_MAP_EDITOR) {
 			game->start_editor();