UI: Make window-projector its own top level QWidget

Previously OBSProjector was a subclass of OBSQTDisplay, which is
intended to own the entire surface it draws on. On wayland some
compositors expect the client to draw decorations (window titlebar), but
because OBSQTDisplay draws on the entire surface directly the client
decorations from QT are overwritten.

Instead promote OBSProjector to a simple QWidget with a single layout
containing the OBSQTDisplay. This allows the OBSQTDisplay to own the
entire contents while OBSProjector draws the decorations.

fixes obsproject#6283

UI/window-projector.cpp

@@ -9,6 +9,16 @@
 #include "qt-wrappers.hpp"
 #include "platform.hpp"
 
+#ifdef ENABLE_WAYLAND
+#include <obs-nix-platform.h>
+#endif
+
+#ifdef _WIN32
+#define NOMINMAX
+#define WIN32_LEAN_AND_MEAN 1
+#include <Windows.h>
+#endif
+
 static QList<OBSProjector *> multiviewProjectors;
 static QList<OBSProjector *> allProjectors;
 
@@ -19,11 +29,16 @@ static size_t maxSrcs, numSrcs;
 
 OBSProjector::OBSProjector(QWidget *widget, obs_source_t *source_, int monitor,
 			   ProjectorType type_)
-	: OBSQTDisplay(widget, Qt::Window),
+	: display(this),
 	  source(source_),
 	  removedSignal(obs_source_get_signal_handler(source), "remove",
 			OBSSourceRemoved, this)
 {
+	QVBoxLayout *layout = new QVBoxLayout;
+	layout->addWidget(&display);
+	layout->setContentsMargins(0, 0, 0, 0);
+	this->setLayout(layout);
+
 	isAlwaysOnTop = config_get_bool(GetGlobalConfig(), "BasicWindow",
 					"ProjectorAlwaysOnTop");
 
@@ -32,7 +47,7 @@ OBSProjector::OBSProjector(QWidget *widget, obs_source_t *source_, int monitor,
 
 	// Mark the window as a projector so SetDisplayAffinity
 	// can skip it
-	windowHandle()->setProperty("isOBSProjectorWindow", true);
+	display.windowHandle()->setProperty("isOBSProjectorWindow", true);
 
 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
 	// Prevents resizing of projector windows
@@ -69,12 +84,13 @@ OBSProjector::OBSProjector(QWidget *widget, obs_source_t *source_, int monitor,
 	auto addDrawCallback = [this]() {
 		bool isMultiview = type == ProjectorType::Multiview;
 		obs_display_add_draw_callback(
-			GetDisplay(),
+			display.GetDisplay(),
 			isMultiview ? OBSRenderMultiview : OBSRender, this);
-		obs_display_set_background_color(GetDisplay(), 0x000000);
+		obs_display_set_background_color(display.GetDisplay(),
+						 0x000000);
 	};
 
-	connect(this, &OBSQTDisplay::DisplayCreated, addDrawCallback);
+	connect(&display, &OBSQTDisplay::DisplayCreated, addDrawCallback);
 	connect(App(), &QGuiApplication::screenRemoved, this,
 		&OBSProjector::ScreenRemoved);
 
@@ -97,17 +113,14 @@ OBSProjector::OBSProjector(QWidget *widget, obs_source_t *source_, int monitor,
 	ready = true;
 
 	show();
-
-	// We need it here to allow keyboard input in X11 to listen to Escape
-	activateWindow();
 }
 
 OBSProjector::~OBSProjector()
 {
 	bool isMultiview = type == ProjectorType::Multiview;
 	obs_display_remove_draw_callback(
-		GetDisplay(), isMultiview ? OBSRenderMultiview : OBSRender,
-		this);
+		display.GetDisplay(),
+		isMultiview ? OBSRenderMultiview : OBSRender, this);
 
 	if (source)
 		obs_source_dec_showing(source);
@@ -874,7 +887,7 @@ static int getSourceByPosition(int x, int y, float ratio)
 
 void OBSProjector::mouseDoubleClickEvent(QMouseEvent *event)
 {
-	OBSQTDisplay::mouseDoubleClickEvent(event);
+	QWidget::mouseDoubleClickEvent(event);
 
 	if (!mouseSwitching)
 		return;
@@ -901,7 +914,7 @@ void OBSProjector::mouseDoubleClickEvent(QMouseEvent *event)
 
 void OBSProjector::mousePressEvent(QMouseEvent *event)
 {
-	OBSQTDisplay::mousePressEvent(event);
+	QWidget::mousePressEvent(event);
 
 	if (event->button() == Qt::RightButton) {
 		OBSBasic *main =
@@ -922,15 +935,26 @@ void OBSProjector::mousePressEvent(QMouseEvent *event)
 					this, SLOT(ResizeToContent()));
 		}
 
-		QAction *alwaysOnTopButton =
-			new QAction(QTStr("Basic.MainMenu.AlwaysOnTop"), this);
-		alwaysOnTopButton->setCheckable(true);
-		alwaysOnTopButton->setChecked(isAlwaysOnTop);
+#ifdef ENABLE_WAYLAND
+		// SetAlwaysOnTop recreates the window and desyncs qt-display, I think.
+		// Causes mis-rendering if toggled on wayland and is disabled in the preview
+		// and main windows.
+		bool isWayland = obs_get_nix_platform() ==
+				 OBS_NIX_PLATFORM_WAYLAND;
+#else
+		bool isWayland = false;
+#endif
+		if (!isWayland) {
+			QAction *alwaysOnTopButton = new QAction(
+				QTStr("Basic.MainMenu.AlwaysOnTop"), this);
+			alwaysOnTopButton->setCheckable(true);
+			alwaysOnTopButton->setChecked(isAlwaysOnTop);
 
-		connect(alwaysOnTopButton, &QAction::toggled, this,
-			&OBSProjector::AlwaysOnTopToggled);
+			connect(alwaysOnTopButton, &QAction::toggled, this,
+				&OBSProjector::AlwaysOnTopToggled);
 
-		popup.addAction(alwaysOnTopButton);
+			popup.addAction(alwaysOnTopButton);
+		}
 
 		popup.addAction(QTStr("Close"), this, SLOT(EscapeTriggered()));
 		popup.exec(QCursor::pos());
@@ -1184,8 +1208,8 @@ void OBSProjector::OpenFullScreenProjector()
 void OBSProjector::OpenWindowedProjector()
 {
 	showFullScreen();
-	showNormal();
 	setCursor(Qt::ArrowCursor);
+	showNormal();
 
 	if (!prevGeometry.isNull())
 		setGeometry(prevGeometry);
@@ -1236,6 +1260,26 @@ void OBSProjector::closeEvent(QCloseEvent *event)
 	event->accept();
 }
 
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+bool OBSProjector::nativeEvent(const QByteArray &, void *message, qintptr *)
+#else
+bool OBSProjector::nativeEvent(const QByteArray &, void *message, long *)
+#endif
+{
+#ifdef _WIN32
+	const MSG &msg = *static_cast<MSG *>(message);
+	switch (msg.message) {
+	case WM_MOVE:
+		display.OnMove();
+		break;
+	case WM_DISPLAYCHANGE:
+		display.OnDisplayChange();
+	}
+#endif
+
+	return false;
+}
+
 bool OBSProjector::IsAlwaysOnTop() const
 {
 	return isAlwaysOnTop;

UI/window-projector.hpp

@@ -26,12 +26,13 @@ enum class MultiviewLayout : uint8_t {
 	SCENES_ONLY_25_SCENES = 9,
 };
 
-class OBSProjector : public OBSQTDisplay {
+class OBSProjector : public QWidget {
 	Q_OBJECT
 
 private:
 	OBSSource source;
 	OBSSignal removedSignal;
+	OBSQTDisplay display;
 
 	static void OBSRenderMultiview(void *data, uint32_t cx, uint32_t cy);
 	static void OBSRender(void *data, uint32_t cx, uint32_t cy);
@@ -40,6 +41,13 @@ class OBSProjector : public OBSQTDisplay {
 	void mousePressEvent(QMouseEvent *event) override;
 	void mouseDoubleClickEvent(QMouseEvent *event) override;
 	void closeEvent(QCloseEvent *event) override;
+#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
+	virtual bool nativeEvent(const QByteArray &eventType, void *message,
+				 qintptr *result) override;
+#else
+	virtual bool nativeEvent(const QByteArray &eventType, void *message,
+				 long *result) override;
+#endif
 
 	bool isAlwaysOnTop;
 	bool isAlwaysOnTopOverridden = false;