Revert "Revert "Add main window shadow for Linux""

This reverts commit b7f5cfe083.

Telegram/SourceFiles/mainwindow.cpp

@@ -39,6 +39,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "apiwrap.h"
 #include "api/api_updates.h"
 #include "settings/settings_intro.h"
+#include "platform/platform_specific.h"
 #include "platform/platform_notifications_manager.h"
 #include "base/platform/base_platform_info.h"
 #include "base/call_delayed.h"
@@ -110,7 +111,12 @@ MainWindow::MainWindow(not_null<Window::Controller*> controller)
 	}, lifetime());
 
 	setAttribute(Qt::WA_NoSystemBackground);
-	setAttribute(Qt::WA_OpaquePaintEvent);
+
+	if (Platform::WindowsNeedShadow()) {
+		setAttribute(Qt::WA_TranslucentBackground);
+	} else {
+		setAttribute(Qt::WA_OpaquePaintEvent);
+	}
 }
 
 void MainWindow::initHook() {

Telegram/SourceFiles/platform/linux/specific_linux.cpp

@@ -81,6 +81,8 @@ constexpr auto kXDGDesktopPortalService = "org.freedesktop.portal.Desktop"_cs;
 constexpr auto kXDGDesktopPortalObjectPath = "/org/freedesktop/portal/desktop"_cs;
 constexpr auto kPropertiesInterface = "org.freedesktop.DBus.Properties"_cs;
 
+constexpr auto kXCBFrameExtentsAtomName = "_GTK_FRAME_EXTENTS"_cs;
+
 QStringList PlatformThemes;
 
 bool IsTrayIconSupported = true;
@@ -298,6 +300,91 @@ bool GetImageFromClipboardSupported() {
 }
 #endif // !TDESKTOP_DISABLE_GTK_INTEGRATION
 
+std::optional<xcb_atom_t> GetXCBAtom(
+		xcb_connection_t *connection,
+		const QString &name) {
+	const auto cookie = xcb_intern_atom(
+		connection,
+		0,
+		name.size(),
+		name.toUtf8());
+
+	auto reply = xcb_intern_atom_reply(
+		connection,
+		cookie,
+		nullptr);
+
+	if (!reply) {
+		return std::nullopt;
+	}
+
+	const auto atom = reply->atom;
+	free(reply);
+
+	return atom;
+}
+
+std::vector<xcb_atom_t> GetXCBWMSupported(xcb_connection_t *connection) {
+	auto netWmAtoms = std::vector<xcb_atom_t>{};
+
+	const auto native = QGuiApplication::platformNativeInterface();
+	if (!native) {
+		return netWmAtoms;
+	}
+
+	const auto root = static_cast<xcb_window_t>(reinterpret_cast<quintptr>(
+		native->nativeResourceForIntegration(QByteArray("rootwindow"))));
+
+	const auto supportedAtom = GetXCBAtom(connection, "_NET_SUPPORTED");
+	if (!supportedAtom.has_value()) {
+		return netWmAtoms;
+	}
+
+	auto offset = 0;
+	auto remaining = 0;
+
+	do {
+		const auto cookie = xcb_get_property(
+			connection,
+			false,
+			root,
+			*supportedAtom,
+			XCB_ATOM_ATOM,
+			offset,
+			1024);
+
+		auto reply = xcb_get_property_reply(
+			connection,
+			cookie,
+			nullptr);
+
+		if (!reply) {
+			break;
+		}
+
+		remaining = 0;
+
+		if (reply->type == XCB_ATOM_ATOM && reply->format == 32) {
+			const auto len = xcb_get_property_value_length(reply)
+				/ sizeof(xcb_atom_t);
+
+			const auto atoms = reinterpret_cast<xcb_atom_t*>(
+				xcb_get_property_value(reply));
+
+			const auto s = netWmAtoms.size();
+			netWmAtoms.resize(s + len);
+			memcpy(netWmAtoms.data() + s, atoms, len * sizeof(xcb_atom_t));
+
+			remaining = reply->bytes_after;
+			offset += len;
+		}
+
+		free(reply);
+	} while (remaining > 0);
+
+	return netWmAtoms;
+}
+
 std::optional<crl::time> XCBLastUserInputTime() {
 	const auto native = QGuiApplication::platformNativeInterface();
 	if (!native) {
@@ -311,24 +398,24 @@ std::optional<crl::time> XCBLastUserInputTime() {
 		return std::nullopt;
 	}
 
-	const auto screen = xcb_setup_roots_iterator(xcb_get_setup(connection)).data;
+	const auto root = static_cast<xcb_window_t>(reinterpret_cast<quintptr>(
-	if (!screen) {
+		native->nativeResourceForIntegration(QByteArray("rootwindow"))));
-		return std::nullopt;
-	}
 
-	const auto cookie = xcb_screensaver_query_info(connection, screen->root);
+	const auto cookie = xcb_screensaver_query_info(
+		connection,
+		root);
 
-	auto info = xcb_screensaver_query_info_reply(
+	auto reply = xcb_screensaver_query_info_reply(
 		connection,
 		cookie,
 		nullptr);
 
-	if (!info) {
+	if (!reply) {
 		return std::nullopt;
 	}
 
-	const auto idle = info->ms_since_user_input;
+	const auto idle = reply->ms_since_user_input;
-	free(info);
+	free(reply);
 
 	return (crl::now() - static_cast<crl::time>(idle));
 }
@@ -468,7 +555,6 @@ enum wl_shell_surface_resize WlResizeFromEdges(Qt::Edges edges) {
 
 bool StartXCBMoveResize(QWindow *window, int edges) {
 	const auto native = QGuiApplication::platformNativeInterface();
-
 	if (!native) {
 		return false;
 	}
@@ -487,29 +573,16 @@ bool StartXCBMoveResize(QWindow *window, int edges) {
 		return false;
 	}
 
-	const auto moveResizeCookie = xcb_intern_atom(
+	const auto moveResize = GetXCBAtom(connection, "_NET_WM_MOVERESIZE");
-		connection,
+	if (!moveResize.has_value()) {
-		0,
-		strlen("_NET_WM_MOVERESIZE"),
-		"_NET_WM_MOVERESIZE");
-
-	auto moveResizeReply = xcb_intern_atom_reply(
-		connection,
-		moveResizeCookie,
-		nullptr);
-
-	if (!moveResizeReply) {
 		return false;
 	}
 
-	const auto moveResize = moveResizeReply->atom;
-	free(moveResizeReply);
-
 	const auto globalPos = QCursor::pos();
 
 	xcb_client_message_event_t xev;
 	xev.response_type = XCB_CLIENT_MESSAGE;
-	xev.type = moveResize;
+	xev.type = *moveResize;
 	xev.sequence = 0;
 	xev.window = window->winId();
 	xev.format = 32;
@@ -582,6 +655,87 @@ bool ShowWaylandWindowMenu(QWindow *window) {
 	return false;
 }
 
+bool XCBFrameExtentsSupported() {
+	const auto native = QGuiApplication::platformNativeInterface();
+	if (!native) {
+		return false;
+	}
+
+	const auto connection = reinterpret_cast<xcb_connection_t*>(
+		native->nativeResourceForIntegration(QByteArray("connection")));
+
+	if (!connection) {
+		return false;
+	}
+
+	const auto frameExtentsAtom = GetXCBAtom(
+		connection,
+		kXCBFrameExtentsAtomName.utf16());
+
+	if (!frameExtentsAtom.has_value()) {
+		return false;
+	}
+
+	return ranges::contains(GetXCBWMSupported(connection), *frameExtentsAtom);
+}
+
+bool SetXCBFrameExtents(QWindow *window, const QMargins &extents) {
+	const auto native = QGuiApplication::platformNativeInterface();
+	if (!native) {
+		return false;
+	}
+
+	const auto connection = reinterpret_cast<xcb_connection_t*>(
+		native->nativeResourceForIntegration(QByteArray("connection")));
+
+	if (!connection) {
+		return false;
+	}
+
+	const auto frameExtentsAtom = GetXCBAtom(
+		connection,
+		kXCBFrameExtentsAtomName.utf16());
+
+	if (!frameExtentsAtom.has_value()) {
+		return false;
+	}
+
+	const auto extentsVector = std::vector<uint>{
+		uint(extents.left()),
+		uint(extents.right()),
+		uint(extents.top()),
+		uint(extents.bottom()),
+	};
+
+	xcb_change_property(
+		connection,
+		XCB_PROP_MODE_REPLACE,
+		window->winId(),
+		*frameExtentsAtom,
+		XCB_ATOM_CARDINAL,
+		32,
+		extentsVector.size(),
+		extentsVector.data());
+
+	return true;
+}
+
+bool SetWaylandWindowGeometry(QWindow *window, const QRect &geometry) {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0) || defined DESKTOP_APP_QT_PATCHED
+	if (const auto waylandWindow = static_cast<QWaylandWindow*>(
+		window->handle())) {
+		if (const auto seat = waylandWindow->display()->lastInputDevice()) {
+			if (const auto shellSurface = waylandWindow->shellSurface()) {
+				shellSurface->setWindowGeometry(geometry);
+				return true;
+			}
+		}
+	}
+#endif // Qt >= 5.13 || DESKTOP_APP_QT_PATCHED
+
+	return false;
+}
+
 Window::Control GtkKeywordToWindowControl(const QString &keyword) {
 	if (keyword == qstr("minimize")) {
 		return Window::Control::Minimize;
@@ -926,6 +1080,31 @@ bool ShowWindowMenu(QWindow *window) {
 	return false;
 }
 
+bool SetWindowExtents(QWindow *window, const QMargins &extents) {
+	if (IsWayland()) {
+		const auto geometry = QRect(QPoint(), window->size())
+			.marginsRemoved(extents);
+
+		return SetWaylandWindowGeometry(window, geometry);
+	} else {
+		return SetXCBFrameExtents(window, extents);
+	}
+}
+
+bool WindowsNeedShadow() {
+#if QT_VERSION >= QT_VERSION_CHECK(5, 13, 0) || defined DESKTOP_APP_QT_PATCHED
+	if (IsWayland()) {
+		return true;
+	}
+#endif // Qt >= 5.13 || DESKTOP_APP_QT_PATCHED
+
+	if (!IsWayland() && XCBFrameExtentsSupported()) {
+		return true;
+	}
+
+	return false;
+}
+
 Window::ControlsLayout WindowControlsLayout() {
 #ifndef TDESKTOP_DISABLE_GTK_INTEGRATION
 	if (Libs::GtkSettingSupported()

Telegram/SourceFiles/platform/mac/specific_mac.h

@@ -44,6 +44,10 @@ inline bool TrayIconSupported() {
 	return true;
 }
 
+inline bool WindowsNeedShadow() {
+	return false;
+}
+
 namespace ThirdParty {
 
 inline void start() {

Telegram/SourceFiles/platform/platform_specific.h

@@ -56,6 +56,8 @@ QImage GetImageFromClipboard();
 bool StartSystemMove(QWindow *window);
 bool StartSystemResize(QWindow *window, Qt::Edges edges);
 bool ShowWindowMenu(QWindow *window);
+bool WindowsNeedShadow();
+bool SetWindowExtents(QWindow *window, const QMargins &extents);
 Window::ControlsLayout WindowControlsLayout();
 
 namespace ThirdParty {

Telegram/SourceFiles/platform/win/specific_win.h

@@ -38,6 +38,10 @@ inline bool TrayIconSupported() {
 	return true;
 }
 
+inline bool WindowsNeedShadow() {
+	return false;
+}
+
 namespace ThirdParty {
 
 void start();

Telegram/SourceFiles/window/main_window.cpp

@@ -10,6 +10,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "storage/localstorage.h"
 #include "platform/platform_window_title.h"
 #include "base/platform/base_platform_info.h"
+#include "ui/platform/ui_platform_utility.h"
 #include "history/history.h"
 #include "window/themes/window_theme.h"
 #include "window/window_session_controller.h"
@@ -33,6 +34,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "facades.h"
 #include "app.h"
 #include "styles/style_window.h"
+#include "styles/style_calls.h" // st::callShadow
 
 #include <QtWidgets/QDesktopWidget>
 #include <QtCore/QMimeData>
@@ -292,6 +294,17 @@ HitTestResult MainWindow::hitTest(const QPoint &p) const {
 	return Window::HitTestResult::None;
 }
 
+bool MainWindow::hasShadow() const {
+	const auto center = geometry().center();
+	return Platform::WindowsNeedShadow()
+		&& Ui::Platform::TranslucentWindowsSupported(center)
+		&& _title;
+}
+
+QRect MainWindow::inner() const {
+	return rect().marginsRemoved(_padding);
+}
+
 int MainWindow::computeMinWidth() const {
 	auto result = st::windowMinWidth;
 	if (const auto session = _controller->sessionController()) {
@@ -302,7 +315,7 @@ int MainWindow::computeMinWidth() const {
 	if (_rightColumn) {
 		result += _rightColumn->width();
 	}
-	return result;
+	return result + _padding.left() + _padding.right();
 }
 
 int MainWindow::computeMinHeight() const {
@@ -311,10 +324,10 @@ int MainWindow::computeMinHeight() const {
 		if (!_outdated) {
 			return 0;
 		}
-		_outdated->resizeToWidth(st::windowMinWidth);
+		_outdated->resizeToWidth(st::windowMinWidth - _padding.left() - _padding.right());
 		return _outdated->height();
 	}();
-	return title + outdated + st::windowMinHeight;
+	return title + outdated + st::windowMinHeight + _padding.top() + _padding.bottom();
 }
 
 void MainWindow::refreshTitleWidget() {
@@ -337,7 +350,20 @@ void MainWindow::updateMinimumSize() {
 	setMinimumHeight(computeMinHeight());
 }
 
+void MainWindow::updateShadowSize() {
+	_padding = hasShadow() && !isMaximized()
+		? st::callShadow.extend
+		: style::margins();
+}
+
 void MainWindow::recountGeometryConstraints() {
+#ifdef Q_OS_LINUX
+	const auto hasShadow = this->hasShadow();
+	setWindowFlag(Qt::NoDropShadowWindowHint, hasShadow);
+	setAttribute(Qt::WA_OpaquePaintEvent, !hasShadow);
+#endif // Q_OS_LINUX
+
+	updateShadowSize();
 	updateMinimumSize();
 	updateControlsGeometry();
 	fixOrder();
@@ -436,7 +462,15 @@ void MainWindow::attachToTrayIcon(not_null<QSystemTrayIcon*> icon) {
 	App::wnd()->updateTrayMenu();
 }
 
+void MainWindow::paintEvent(QPaintEvent *e) {
+	if (hasShadow() && !isMaximized()) {
+		QPainter p(this);
+		Ui::Shadow::paint(p, inner(), width(), st::callShadow);
+	}
+}
+
 void MainWindow::resizeEvent(QResizeEvent *e) {
+	updateShadowSize();
 	updateControlsGeometry();
 }
 
@@ -449,27 +483,28 @@ void MainWindow::leaveEventHook(QEvent *e) {
 }
 
 void MainWindow::updateControlsGeometry() {
-	auto bodyLeft = 0;
+	const auto inner = this->inner();
-	auto bodyTop = 0;
+	auto bodyLeft = inner.x();
-	auto bodyWidth = width();
+	auto bodyTop = inner.y();
+	auto bodyWidth = inner.width();
 	if (_title && !_title->isHidden()) {
-		_title->setGeometry(0, bodyTop, width(), _title->height());
+		_title->setGeometry(inner.x(), bodyTop, inner.width(), _title->height());
 		bodyTop += _title->height();
 	}
 	if (_titleShadow) {
-		_titleShadow->setGeometry(0, bodyTop, width(), st::lineWidth);
+		_titleShadow->setGeometry(inner.x(), bodyTop, inner.width(), st::lineWidth);
 	}
 	if (_outdated) {
 		Ui::SendPendingMoveResizeEvents(_outdated.data());
-		_outdated->resizeToWidth(width());
+		_outdated->resizeToWidth(inner.width());
-		_outdated->moveToLeft(0, bodyTop);
+		_outdated->moveToLeft(inner.x(), bodyTop);
 		bodyTop += _outdated->height();
 	}
 	if (_rightColumn) {
 		bodyWidth -= _rightColumn->width();
-		_rightColumn->setGeometry(bodyWidth, bodyTop, width() - bodyWidth, height() - bodyTop);
+		_rightColumn->setGeometry(bodyWidth, bodyTop, inner.width() - bodyWidth, inner.height() - (bodyTop - inner.y()));
 	}
-	_body->setGeometry(bodyLeft, bodyTop, bodyWidth, height() - bodyTop);
+	_body->setGeometry(bodyLeft, bodyTop, bodyWidth, inner.height() - (bodyTop - inner.y()));
 }
 
 void MainWindow::updateUnreadCounter() {
@@ -599,12 +634,12 @@ void MainWindow::showRightColumn(object_ptr<TWidget> widget) {
 
 int MainWindow::maximalExtendBy() const {
 	auto desktop = QDesktopWidget().availableGeometry(this);
-	return std::max(desktop.width() - geometry().width(), 0);
+	return std::max(desktop.width() - inner().width(), 0);
 }
 
 bool MainWindow::canExtendNoMove(int extendBy) const {
 	auto desktop = QDesktopWidget().availableGeometry(this);
-	auto inner = geometry();
+	auto inner = geometry().marginsRemoved(_padding);
 	auto innerRight = (inner.x() + inner.width() + extendBy);
 	auto desktopRight = (desktop.x() + desktop.width());
 	return innerRight <= desktopRight;

Telegram/SourceFiles/window/main_window.h

@@ -101,12 +101,15 @@ public:
 
 	void clearWidgets();
 
+	QRect inner() const;
 	int computeMinWidth() const;
 	int computeMinHeight() const;
 
 	void recountGeometryConstraints();
 	virtual void updateControlsGeometry();
 
+	bool hasShadow() const;
+
 public slots:
 	bool minimizeToTray();
 	void updateGlobalMenu() {
@@ -114,6 +117,7 @@ public slots:
 	}
 
 protected:
+	void paintEvent(QPaintEvent *e) override;
 	void resizeEvent(QResizeEvent *e) override;
 	void leaveEventHook(QEvent *e) override;
 
@@ -179,6 +183,7 @@ protected:
 private:
 	void refreshTitleWidget();
 	void updateMinimumSize();
+	void updateShadowSize();
 	void updatePalette();
 	void initSize();
 
@@ -198,6 +203,7 @@ private:
 	QIcon _icon;
 	bool _usingSupportIcon = false;
 	QString _titleText;
+	style::margins _padding;
 
 	bool _isActive = false;
 

Telegram/SourceFiles/window/window_title_qt.cpp

@@ -8,11 +8,13 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "window/window_title_qt.h"
 
 #include "platform/platform_specific.h"
+#include "ui/platform/ui_platform_utility.h"
 #include "ui/widgets/buttons.h"
 #include "ui/widgets/shadow.h"
 #include "core/core_settings.h"
 #include "core/application.h"
 #include "styles/style_window.h"
+#include "styles/style_calls.h" // st::callShadow
 #include "base/call_delayed.h"
 
 #include <QtGui/QGuiApplication>
@@ -27,6 +29,10 @@ namespace {
 // that window. If we show the window back with this delay it works.
 constexpr auto kShowAfterFramelessToggleDelay = crl::time(1000);
 
+style::margins ShadowExtents() {
+	return st::callShadow.extend;
+}
+
 } // namespace
 
 TitleWidgetQt::TitleWidgetQt(QWidget *parent)
@@ -63,12 +69,17 @@ TitleWidgetQt::TitleWidgetQt(QWidget *parent)
 
 	QCoreApplication::instance()->installEventFilter(this);
 
-	_windowWasFrameless = (window()->windowFlags() & Qt::FramelessWindowHint) != 0;
+	_windowWasFrameless = (window()->windowFlags()
+		& Qt::FramelessWindowHint) != 0;
+
 	if (!_windowWasFrameless) {
 		toggleFramelessWindow(true);
 	}
+
 	setAttribute(Qt::WA_OpaquePaintEvent);
 	resize(width(), _st.height);
+
+	updateWindowExtents();
 }
 
 TitleWidgetQt::~TitleWidgetQt() {
@@ -76,6 +87,7 @@ TitleWidgetQt::~TitleWidgetQt() {
 	if (!_windowWasFrameless) {
 		toggleFramelessWindow(false);
 	}
+	Platform::SetWindowExtents(window()->windowHandle(), QMargins());
 }
 
 void TitleWidgetQt::toggleFramelessWindow(bool enabled) {
@@ -98,11 +110,22 @@ void TitleWidgetQt::init() {
 		&QWindow::windowStateChanged,
 		this,
 		[=](Qt::WindowState state) { windowStateChanged(state); });
+	connect(
+		window()->windowHandle(),
+		&QWindow::visibleChanged,
+		this,
+		[=](bool visible) { visibleChanged(visible); });
 	_maximizedState = (window()->windowState() & Qt::WindowMaximized);
 	_activeState = isActiveWindow();
 	updateButtonsState();
 }
 
+bool TitleWidgetQt::hasShadow() const {
+	const auto center = window()->geometry().center();
+	return Platform::WindowsNeedShadow()
+		&& Ui::Platform::TranslucentWindowsSupported(center);
+}
+
 void TitleWidgetQt::paintEvent(QPaintEvent *e) {
 	auto active = isActiveWindow();
 	if (_activeState != active) {
@@ -112,6 +135,14 @@ void TitleWidgetQt::paintEvent(QPaintEvent *e) {
 	Painter(this).fillRect(rect(), active ? _st.bgActive : _st.bg);
 }
 
+void TitleWidgetQt::updateWindowExtents() {
+	if (hasShadow() && !_maximizedState) {
+		Platform::SetWindowExtents(window()->windowHandle(), ShadowExtents());
+	} else {
+		Platform::SetWindowExtents(window()->windowHandle(), QMargins());
+	}
+}
+
 void TitleWidgetQt::updateControlsPosition() {
 	const auto controlsLayout = Core::App().settings().windowControlsLayout();
 	const auto controlsLeft = controlsLayout.left;
@@ -197,7 +228,7 @@ void TitleWidgetQt::mousePressEvent(QMouseEvent *e) {
 }
 
 void TitleWidgetQt::mouseDoubleClickEvent(QMouseEvent *e) {
-	if (window()->windowState() == Qt::WindowMaximized) {
+	if (_maximizedState) {
 		window()->setWindowState(Qt::WindowNoState);
 	} else {
 		window()->setWindowState(Qt::WindowMaximized);
@@ -205,11 +236,19 @@ void TitleWidgetQt::mouseDoubleClickEvent(QMouseEvent *e) {
 }
 
 bool TitleWidgetQt::eventFilter(QObject *obj, QEvent *e) {
+	// I tried to listen only QEvent::Move and QEvent::Resize
+	// but that didn't work
+	if (obj->isWidgetType()
+		&& window() == static_cast<QWidget*>(obj)) {
+		updateWindowExtents();
+	}
+
 	if (e->type() == QEvent::MouseMove
 		|| e->type() == QEvent::MouseButtonPress) {
 		if (window()->isAncestorOf(static_cast<QWidget*>(obj))) {
 			const auto mouseEvent = static_cast<QMouseEvent*>(e);
-			const auto edges = edgesFromPos(mouseEvent->windowPos().toPoint());
+			const auto edges = edgesFromPos(
+				mouseEvent->windowPos().toPoint());
 
 			if (e->type() == QEvent::MouseMove
 				&& mouseEvent->buttons() == Qt::NoButton) {
@@ -218,7 +257,7 @@ bool TitleWidgetQt::eventFilter(QObject *obj, QEvent *e) {
 
 			if (e->type() == QEvent::MouseButtonPress
 				&& mouseEvent->button() == Qt::LeftButton
-				&& window()->windowState() != Qt::WindowMaximized) {
+				&& !_maximizedState) {
 				return startResize(edges);
 			}
 		}
@@ -243,6 +282,12 @@ void TitleWidgetQt::windowStateChanged(Qt::WindowState state) {
 	}
 }
 
+void TitleWidgetQt::visibleChanged(bool visible) {
+	if (visible) {
+		updateWindowExtents();
+	}
+}
+
 void TitleWidgetQt::updateButtonsState() {
 	_minimize->setIconOverride(_activeState
 		? &_st.minimizeIconActive
@@ -273,26 +318,48 @@ void TitleWidgetQt::updateButtonsState() {
 		: nullptr);
 }
 
+int TitleWidgetQt::getResizeArea(Qt::Edge edge) const {
+	if (!hasShadow()) {
+		return st::windowResizeArea;
+	}
+
+	if (edge == Qt::LeftEdge) {
+		return ShadowExtents().left();
+	} else if (edge == Qt::RightEdge) {
+		return ShadowExtents().right();
+	} else if (edge == Qt::TopEdge) {
+		return ShadowExtents().top();
+	} else if (edge == Qt::BottomEdge) {
+		return ShadowExtents().bottom();
+	}
+
+	return 0;
+}
+
 Qt::Edges TitleWidgetQt::edgesFromPos(const QPoint &pos) {
-	if (pos.x() <= st::windowResizeArea) {
+	if (pos.x() <= getResizeArea(Qt::LeftEdge)) {
-		if (pos.y() <= st::windowResizeArea) {
+		if (pos.y() <= getResizeArea(Qt::TopEdge)) {
 			return Qt::LeftEdge | Qt::TopEdge;
-		} else if (pos.y() >= (window()->height() - st::windowResizeArea)) {
+		} else if (pos.y()
+			>= (window()->height() - getResizeArea(Qt::BottomEdge))) {
 			return Qt::LeftEdge | Qt::BottomEdge;
 		}
 
 		return Qt::LeftEdge;
-	} else if (pos.x() >= (window()->width() - st::windowResizeArea)) {
+	} else if (pos.x()
-		if (pos.y() <= st::windowResizeArea) {
+		>= (window()->width() - getResizeArea(Qt::RightEdge))) {
+		if (pos.y() <= getResizeArea(Qt::TopEdge)) {
 			return Qt::RightEdge | Qt::TopEdge;
-		} else if (pos.y() >= (window()->height() - st::windowResizeArea)) {
+		} else if (pos.y()
+			>= (window()->height() - getResizeArea(Qt::BottomEdge))) {
 			return Qt::RightEdge | Qt::BottomEdge;
 		}
 
 		return Qt::RightEdge;
-	} else if (pos.y() <= st::windowResizeArea) {
+	} else if (pos.y() <= getResizeArea(Qt::TopEdge)) {
 		return Qt::TopEdge;
-	} else if (pos.y() >= (window()->height() - st::windowResizeArea)) {
+	} else if (pos.y()
+		>= (window()->height() - getResizeArea(Qt::BottomEdge))) {
 		return Qt::BottomEdge;
 	} else {
 		return 0;
@@ -307,7 +374,7 @@ void TitleWidgetQt::restoreCursor() {
 }
 
 void TitleWidgetQt::updateCursor(Qt::Edges edges) {
-	if (!edges || window()->windowState() == Qt::WindowMaximized) {
+	if (!edges || _maximizedState) {
 		restoreCursor();
 		return;
 	} else if (!QGuiApplication::overrideCursor()) {

Telegram/SourceFiles/window/window_title_qt.h

@@ -39,6 +39,8 @@ protected:
 
 private:
 	void windowStateChanged(Qt::WindowState state = Qt::WindowNoState);
+	void visibleChanged(bool visible);
+	void updateWindowExtents();
 	void updateButtonsState();
 	void updateControlsPosition();
 	void updateControlsPositionBySide(
@@ -46,6 +48,8 @@ private:
 		bool right);
 
 	void toggleFramelessWindow(bool enabled);
+	bool hasShadow() const;
+	int getResizeArea(Qt::Edge edge) const;
 	Qt::Edges edgesFromPos(const QPoint &pos);
 	void updateCursor(Qt::Edges edges);
 	void restoreCursor();