Fix graphics flickering/stretching on Windows (#367)

* DRY, standardized window top offset
* handle_splash_events() handle multiple events per frame
* accurate windows menubar height for multiple rows
* Windows filter a resize event triggered by the menubar
* windows expand small window to fit menubar
* splash screens draw in view rect, not window rect

src/game/boe.graphics.cpp

@@ -145,12 +145,9 @@ void adjust_window_mode() {
 	// 0 - center 1- ul 2 - ur 3 - dl 4 - dr 5 - small win
 	int mode = get_int_pref("DisplayMode");
 	if(mode == 5) {
-		// Increase window height to make room for the menubar
+		// Increase window height to make room for the menubar on Linux
 		int winHeight = height;
-#ifndef _WIN32
-		// Not on Windows, for some reason
-		winHeight += getMenubarHeight();
-#endif
+		winHeight += os_specific_y_offset();
 
 		mainPtr.create(sf::VideoMode(width, winHeight, 32), "Blades of Exile", sf::Style::Titlebar | sf::Style::Close, winSettings);
 
@@ -179,6 +176,7 @@ void adjust_window_mode() {
 	init_fileio();
 #endif
 	init_menubar();
+	adjust_window_for_menubar(mode, width, height);
 	showMenuBar();
 }
 
@@ -190,16 +188,6 @@ sf::FloatRect compute_viewport(const sf::RenderWindow& mainPtr, int mode, float
 	// Dimensions of the OS window.
 	rectangle windRect { mainPtr };
 
-	// This is an additional offset between the "logical" top of the window an the UI.
-	// On Windows and Mac no offset is needed because the menubar is not a part of the mainPtr, but
-	// on Linux it is.
-	int os_specific_y_offset =
-#if defined(SFML_SYSTEM_WINDOWS) || defined(SFML_SYSTEM_MAC)
-		0;
-#else
-		getMenubarHeight();
-#endif
-
 	// Width and height: how large the viewport is. They seem to be calculated
 	// in terms of *source* dimensions, with values above 1 resulting in an upscale.
 	viewport.width  = ui_scale * width / windRect.width();
@@ -215,15 +203,15 @@ sf::FloatRect compute_viewport(const sf::RenderWindow& mainPtr, int mode, float
 	if(mode == 0) {
 		// Fullscreen centered
 		viewport.left = float((windRect.width() - width) / 2) / windRect.width();
-		viewport.top  = float((windRect.height() - height - os_specific_y_offset) / 2)/ windRect.height();
+		viewport.top  = float((windRect.height() - height - os_specific_y_offset()) / 2)/ windRect.height();
 	} else if(mode == 1) {
 		// Fullscreen top left
 		viewport.left = float(extra_horizontal_buffer) / windRect.width();
-		viewport.top  = float(os_specific_y_offset) / windRect.height();
+		viewport.top  = float(os_specific_y_offset()) / windRect.height();
 	} else if(mode == 2) {
 		// Fullscreen top right
 		viewport.left = float(windRect.right - width - extra_horizontal_buffer) / windRect.width();
-		viewport.top  = float(os_specific_y_offset) / windRect.height();
+		viewport.top  = float(os_specific_y_offset()) / windRect.height();
 	} else if(mode == 3) {
 		// Fullscreen bottom left
 		viewport.left = float(extra_horizontal_buffer) / windRect.width();
@@ -231,16 +219,16 @@ sf::FloatRect compute_viewport(const sf::RenderWindow& mainPtr, int mode, float
 		// there could be a windows taskbar / mac os dock / xfce taskbar / etc that consumes a part
 		// of that display, and that we do not know size of. So we need to account for that somehow,
 		// so we add 28 more pixels (this was the amount in the previous version of this code).
-		viewport.top  = float(windRect.bottom - height - os_specific_y_offset - 28) / windRect.height();
+		viewport.top  = float(windRect.bottom - height - os_specific_y_offset() - 28) / windRect.height();
 	} else if(mode == 4) {
 		// Fullscreen bottom right
 		viewport.left = float(windRect.right - width - extra_horizontal_buffer) / windRect.width();
 		// DIRTY HACK: same as for mode 3
-		viewport.top  = float(windRect.bottom - height - os_specific_y_offset - 28) / windRect.height();
+		viewport.top  = float(windRect.bottom - height - os_specific_y_offset() - 28) / windRect.height();
 	} else if(mode == 5) {
 		// Small windowed
 		viewport.left = 0;
-		viewport.top  = float(os_specific_y_offset) / windRect.height();
+		viewport.top  = float(os_specific_y_offset()) / windRect.height();
 	}
 
 	return viewport;

src/game/boe.graphics.hpp

@@ -51,6 +51,7 @@ void draw_startup_stats();
 void draw_trim(short q,short r,short which_trim,ter_num_t ground_ter);
 sf::FloatRect compute_viewport(const sf::RenderWindow&, int mode, float ui_scale, float width, float height);
 
+
 void draw_startup_anim(bool advance);
 
 

src/game/boe.menus.win.cpp

@@ -69,17 +69,12 @@ void init_menubar() {
 	if(winHandle == NULL) return;
 	if(menuHandle == NULL)
 		menuHandle = LoadMenu(GetModuleHandle(NULL), MAKEINTRESOURCE(IDC_BLADESOFEXILE));
-	SetMenu(winHandle, menuHandle);
 	// Now we have to do a little hack to handle menu messages.
 	// We replace SFML's window procedure with our own, which checks for menu events and then forwards to SFML's procedure.
 	mainProc = SetWindowLongPtr(winHandle, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(&menuProc));
+	SetMenu(winHandle, menuHandle);
+
 	mainPtr.setActive();
-	// Fix the window's viewport so that everything is drawn correctly
-	sf::Vector2u sz = mainPtr.getSize();
-	double menubarHeight = getMenubarHeight();
-	double usableHeight = sz.y - menubarHeight;
-	sf::View view(sf::FloatRect(0, 0, sz.x, usableHeight));
-	mainPtr.setView(view);
 	
 	// And now initialize the mapping from Windows menu commands to eMenu constants
 	static bool inited = false;
@@ -291,6 +286,16 @@ void showMenuBar() {
 
 LRESULT CALLBACK menuProc(HWND handle, UINT message, WPARAM wParam, LPARAM lParam) {
 	MSG msg = {handle, message, wParam, lParam};
+	
+	// Adding the menubar to the window for the first time triggers an unwanted
+	// resizing of the window, which we skip processing because it skews our
+	// viewport:
+	static bool menubarTriggeredResize = false;
+	if(message == WM_SIZE && !menubarTriggeredResize) {
+		menubarTriggeredResize = true;
+		return true;
+	}
+
 	if(HIWORD(wParam) != 1 || message != WM_COMMAND) {
 		if(TranslateAccelerator(handle, accel.handle, &msg))
 			return 0;

src/game/boe.startup.cpp

@@ -109,18 +109,23 @@ bool handle_startup_press(location the_point) {
 
 void handle_splash_events() {
 	sf::Event event;
-	if(!mainPtr.pollEvent(event)) return;
-	if(event.type == sf::Event::GainedFocus || event.type == sf::Event::MouseMoved)
-		set_cursor(sword_curs);
+	while(mainPtr.pollEvent(event)) {
+		if(event.type == sf::Event::GainedFocus || event.type == sf::Event::MouseMoved)
+			set_cursor(sword_curs);
+	}
+}
+
+rectangle view_rect() {
+	sf::Vector2f size = mainPtr.getView().getSize();
+	return rectangle(0, 0, size.y, size.x);
 }
 
 void show_logo() {
-	rectangle whole_window;
+	rectangle whole_window = view_rect();
 	
 	if(get_int_pref("DisplayMode") != 5)
 		hideMenuBar();
 	
-	whole_window = rectangle(mainPtr);
 	double ui_scale = get_float_pref("UIScale", 1.0);
 	if(ui_scale < 1) ui_scale = 1;
 	rectangle logo_from = {0, 0, int(ui_scale *350), int(ui_scale * 350)};
@@ -141,11 +146,12 @@ void show_logo() {
 }
 
 void plop_fancy_startup() {
+	rectangle whole_window = view_rect();
+
 	float ui_scale = get_float_pref("UIScale", 1.0);
 	if (ui_scale<1) ui_scale=1;
-	rectangle whole_window,from_rect;
+	rectangle from_rect;
 	rectangle intro_from = {0, 0, int(ui_scale * 480), int(ui_scale * 640)};
-	whole_window = rectangle(mainPtr);
 	sf::Time delay = time_in_ticks(220);
 	intro_from.offset((whole_window.right - intro_from.right) / 2,(whole_window.bottom - intro_from.bottom) / 2);
 	sf::Texture& pict_to_draw = *ResMgr::graphics.get("startsplash", true);