Qt: Fix fullscreening in Wayland

pcsx2-qt/DisplayWidget.cpp

@@ -24,6 +24,7 @@
 #include <QtCore/QDebug>
 #include <QtGui/QGuiApplication>
 #include <QtGui/QKeyEvent>
+#include <QtGui/QResizeEvent>
 #include <QtGui/QScreen>
 #include <QtGui/QWindow>
 #include <QtGui/QWindowStateChangeEvent>
@@ -208,7 +209,12 @@ bool DisplayWidget::event(QEvent* event)
 		{
 			QWidget::event(event);
 
-			emit windowResizedEvent(scaledWindowWidth(), scaledWindowHeight(), devicePixelRatioFromScreen());
+			const qreal dpr = devicePixelRatioFromScreen();
+			const QSize size = static_cast<QResizeEvent*>(event)->size();
+			const int width = static_cast<int>(std::ceil(static_cast<qreal>(size.width()) * devicePixelRatioFromScreen()));
+			const int height = static_cast<int>(std::ceil(static_cast<qreal>(size.height()) * devicePixelRatioFromScreen()));
+
+			emit windowResizedEvent(width, height, dpr);
 			return true;
 		}
 
@@ -262,7 +268,7 @@ bool DisplayContainer::IsNeeded(bool fullscreen, bool render_to_main)
 #if defined(_WIN32) || defined(__APPLE__)
 	return false;
 #else
-	if (fullscreen || render_to_main)
+	if (!fullscreen && render_to_main)
 		return false;
 
 	// We only need this on Wayland because of client-side decorations...

pcsx2-qt/EmuThread.cpp

@@ -603,9 +603,6 @@ void EmuThread::updateDisplay()
 		pxFailRel("Failed to recreate context after updating");
 		return;
 	}
-
-	// this is always a new widget, so reconnect it
-	connectDisplaySignals(widget);
 }
 
 HostDisplay* EmuThread::acquireHostDisplay(HostDisplay::RenderAPI api)

pcsx2-qt/EmuThread.h

@@ -47,6 +47,7 @@ public:
 
 	/// Called back from the GS thread when the display state changes (e.g. fullscreen, render to main).
 	HostDisplay* acquireHostDisplay(HostDisplay::RenderAPI api);
+	void connectDisplaySignals(DisplayWidget* widget);
 	void releaseHostDisplay();
 	void updateDisplay();
 
@@ -127,7 +128,6 @@ private:
 	static constexpr u32 BACKGROUND_CONTROLLER_POLLING_INTERVAL =
 		100; /// Interval at which the controllers are polled when the system is not active.
 
-	void connectDisplaySignals(DisplayWidget* widget);
 	void destroyVM();
 	void executeVM();
 	void checkForSettingChanges();

pcsx2-qt/MainWindow.cpp

@@ -1140,8 +1140,6 @@ DisplayWidget* MainWindow::createDisplay(bool fullscreen, bool render_to_main)
 			container->showFullScreen();
 		else
 			container->showNormal();
-
-		// updateMouseMode(System::IsPaused());
 	}
 	else if (!render_to_main)
 	{
@@ -1150,7 +1148,7 @@ DisplayWidget* MainWindow::createDisplay(bool fullscreen, bool render_to_main)
 	}
 	else
 	{
-		m_ui.mainContainer->insertWidget(1, m_display_widget);
+		m_ui.mainContainer->insertWidget(1, container);
 		switchToEmulationView();
 	}
 
@@ -1165,6 +1163,8 @@ DisplayWidget* MainWindow::createDisplay(bool fullscreen, bool render_to_main)
 		return nullptr;
 	}
 
+	g_emu_thread->connectDisplaySignals(m_display_widget);
+
 	if (!host_display->CreateRenderDevice(wi.value(), Host::GetStringSettingValue("EmuCore/GS", "Adapter", ""), EmuConfig.GetEffectiveVsyncMode(),
 			Host::GetBoolSettingValue("EmuCore/GS", "ThreadedPresentation", false), Host::GetBoolSettingValue("EmuCore/GS", "UseDebugDevice", false)))
 	{
@@ -1183,34 +1183,35 @@ DisplayWidget* MainWindow::createDisplay(bool fullscreen, bool render_to_main)
 DisplayWidget* MainWindow::updateDisplay(bool fullscreen, bool render_to_main)
 {
 	HostDisplay* host_display = Host::GetHostDisplay();
-	const bool is_fullscreen = m_display_widget->isFullScreen();
+	QWidget* container = m_display_container ? static_cast<QWidget*>(m_display_container) : static_cast<QWidget*>(m_display_widget);
-	const bool is_rendering_to_main = (!is_fullscreen && m_display_widget->parent());
+	const bool is_fullscreen = container->isFullScreen();
+	const bool is_rendering_to_main = (!is_fullscreen && container->parent());
 	const std::string fullscreen_mode(QtHost::GetBaseStringSettingValue("EmuCore/GS", "FullscreenMode", ""));
 	const bool is_exclusive_fullscreen = (fullscreen && !fullscreen_mode.empty() && host_display->SupportsFullscreen());
 	if (fullscreen == is_fullscreen && is_rendering_to_main == render_to_main)
 		return m_display_widget;
 
 	// Skip recreating the surface if we're just transitioning between fullscreen and windowed with render-to-main off.
+	// .. except on Wayland, where everything tends to break if you don't recreate.
 	const bool has_container = (m_display_container != nullptr);
 	const bool needs_container = DisplayContainer::IsNeeded(fullscreen, render_to_main);
-	if (!is_rendering_to_main && !render_to_main && !is_exclusive_fullscreen && has_container == needs_container)
+	if (!is_rendering_to_main && !render_to_main && !is_exclusive_fullscreen && has_container == needs_container && !needs_container)
 	{
-		qDebug() << "Toggling to" << (fullscreen ? "fullscreen" : "windowed") << "without recreating surface";
+		Console.WriteLn("Toggling to %s without recreating surface", (fullscreen ? "fullscreen" : "windowed"));
 		if (host_display->IsFullscreen())
 			host_display->SetFullscreen(false, 0, 0, 0.0f);
 
 		if (fullscreen)
 		{
-			m_display_widget->showFullScreen();
+			container->showFullScreen();
 		}
 		else
 		{
 			restoreDisplayWindowGeometryFromConfig();
-			m_display_widget->showNormal();
+			container->showNormal();
 		}
 
 		QCoreApplication::processEvents(QEventLoop::ExcludeUserInputEvents);
-		// updateMouseMode(System::IsPaused());
 		return m_display_widget;
 	}
 
@@ -1218,7 +1219,6 @@ DisplayWidget* MainWindow::updateDisplay(bool fullscreen, bool render_to_main)
 
 	destroyDisplayWidget();
 
-	QWidget* container;
 	if (DisplayContainer::IsNeeded(fullscreen, render_to_main))
 	{
 		m_display_container = new DisplayContainer();
@@ -1241,8 +1241,6 @@ DisplayWidget* MainWindow::updateDisplay(bool fullscreen, bool render_to_main)
 			container->showFullScreen();
 		else
 			container->showNormal();
-
-		// updateMouseMode(System::IsPaused());
 	}
 	else if (!render_to_main)
 	{
@@ -1251,7 +1249,7 @@ DisplayWidget* MainWindow::updateDisplay(bool fullscreen, bool render_to_main)
 	}
 	else
 	{
-		m_ui.mainContainer->insertWidget(1, m_display_widget);
+		m_ui.mainContainer->insertWidget(1, container);
 		switchToEmulationView();
 	}
 
@@ -1266,6 +1264,8 @@ DisplayWidget* MainWindow::updateDisplay(bool fullscreen, bool render_to_main)
 		return nullptr;
 	}
 
+	g_emu_thread->connectDisplaySignals(m_display_widget);
+
 	if (!host_display->ChangeRenderWindow(wi.value()))
 		pxFailRel("Failed to recreate surface on new widget.");
 
@@ -1344,7 +1344,8 @@ void MainWindow::destroyDisplayWidget()
 	if (!m_display_widget)
 		return;
 
-	if (m_display_container || (!m_display_widget->parent() && !m_display_widget->isFullScreen()))
+	const QWidget* container = m_display_container ? static_cast<QWidget*>(m_display_container) : static_cast<QWidget*>(m_display_widget);
+	if (!container->parent() && !container->isFullScreen())
 		saveDisplayWindowGeometryToConfig();
 
 	if (m_display_container)