refactor: Remove manual high-dpi support

This removes the --scale command line option.
Qt6 seems to have this already integrated to scale according to the
nativ display settings: https://doc.qt.io/qt-6.8/highdpi.html
Adjusting the scale on a per-application basis is not intended (anymore)
according to the documentation.
Tested on a (near) high-dpi screen.

Author: ltoenning

samples/hotkey/main.cpp

@@ -16,7 +16,6 @@ using namespace swift::gui;
 //! main
 int main(int argc, char *argv[])
 {
-    CGuiApplication::highDpiScreenSupport();
     QApplication qa(argc, argv);
     CGuiApplication a("samplehotkey", swift::misc::CApplicationInfo::Sample, QPixmap());
     swift::gui::components::CSettingsHotkeyComponent w;

src/gui/guiapplication.cpp

@@ -105,7 +105,6 @@ namespace swift::gui
     {
         this->addWindowModeOption();
         this->addWindowResetSizeOption();
-        this->addWindowScaleSizeOption();
 
         // notify when app goes down
         connect(qGuiApp, &QGuiApplication::lastWindowClosed, this, &CGuiApplication::gracefulShutdown);
@@ -150,15 +149,6 @@ namespace swift::gui
         this->addParserOption(m_cmdWindowSizeReset);
     }
 
-    void CGuiApplication::addWindowScaleSizeOption()
-    {
-        // just added here to display it in help
-        // parseScaleFactor() is used since it is needed upfront (before application is created)
-        m_cmdWindowScaleSize =
-            QCommandLineOption("scale", QCoreApplication::translate("main", "Scale: number."), "scalevalue");
-        this->addParserOption(m_cmdWindowScaleSize);
-    }
-
     void CGuiApplication::addWindowStateOption()
     {
         m_cmdWindowStateMinimized = QCommandLineOption(
@@ -287,28 +277,6 @@ namespace swift::gui
 
     void CGuiApplication::exit(int retcode) { CApplication::exit(retcode); }
 
-    void CGuiApplication::highDpiScreenSupport(const QString &scaleFactor)
-    {
-        // https://lists.qt-project.org/pipermail/development/2019-September/037434.html
-        // QSize s = CGuiUtility::physicalScreenSizeOs();
-        QString sf = scaleFactor.trimmed().isEmpty() ? defaultScaleFactorString() : scaleFactor;
-        if (sf.contains('/'))
-        {
-            const double sfd = parseFraction(scaleFactor, -1);
-            sf = sfd < 0 ? "1.0" : QString::number(sfd, 'f', 8);
-        }
-
-        sf = cleanNumber(sf);
-
-        // qputenv("QT_ENABLE_HIGHDPI_SCALING", "1");
-        QGuiApplication::setHighDpiScaleFactorRoundingPolicy(Qt::HighDpiScaleFactorRoundingPolicy::Floor);
-
-        const QByteArray sfa = sf.toLatin1();
-        qputenv("QT_SCALE_FACTOR", sfa);
-    }
-
-    bool CGuiApplication::isUsingHighDpiScreenSupport() { return CGuiUtility::isUsingHighDpiScreenSupport(); }
-
     QScreen *CGuiApplication::currentScreen()
     {
         const QWidget *w = CGuiApplication::mainApplicationWidget();
@@ -455,53 +423,6 @@ namespace swift::gui
         }
     }
 
-    double CGuiApplication::parseScaleFactor(int argc, char *argv[])
-    {
-        for (int i = 1; i < argc; ++i)
-        {
-            if (qstrcmp(argv[i], "--scale") == 0 || qstrcmp(argv[i], "-scale") == 0)
-            {
-                if (i + 1 >= argc) { return -1.0; } // no value
-                const QString factor(argv[i + 1]);
-                bool ok;
-                const double f = factor.toDouble(&ok);
-                return ok ? f : -1.0;
-            }
-        }
-        return -1.0;
-    }
-
-    QString CGuiApplication::scaleFactor(int argc, char *argv[])
-    {
-        for (int i = 1; i < argc; ++i)
-        {
-            if (qstrcmp(argv[i], "--scale") == 0 || qstrcmp(argv[i], "-scale") == 0)
-            {
-                if (i + 1 >= argc) { return QString(); } // no value
-                const QString factor(argv[i + 1]);
-                return factor.trimmed();
-            }
-        }
-        return QString();
-    }
-
-    QString CGuiApplication::defaultScaleFactorString()
-    {
-        if (!CBuildConfig::isRunningOnWindowsNtPlatform()) { return "1.0"; }
-
-        // On windows
-        // Qt 5.14.1 default is device ratio 3
-        // Qt 5.14.0 default device ratio was 2
-
-        // 2/3 (0.66667) => device ratio 3
-        // 0.75 => device ratio 2.25
-        // 0.8  => device ratio 2.4
-        // 1.00 => device ratio 3
-
-        // currently NOT used
-        return "1.0";
-    }
-
     void CGuiApplication::cmdLineErrorMessage(const QString &text, const QString &informativeText) const
     {
         QMessageBox errorBox(QMessageBox::Critical, QGuiApplication::applicationDisplayName(), "<b>" + text + "</b>");

src/gui/guiapplication.h

@@ -90,9 +90,6 @@ namespace swift::gui
         //! CMD line arguments (reset size store)
         void addWindowResetSizeOption();
 
-        //! CMD line arguments (scale size on DPI screens)
-        void addWindowScaleSizeOption();
-
         //! Window state
         Qt::WindowState getWindowState() const;
 
@@ -255,13 +252,6 @@ namespace swift::gui
         //! Exit application, perform graceful shutdown and exit
         static void exit(int retcode = 0);
 
-        //! Support for high DPI screens
-        //! \note Needs to be at the beginning of main
-        static void highDpiScreenSupport(const QString &scaleFactor = {});
-
-        //! Uses the high DPI support?
-        static bool isUsingHighDpiScreenSupport();
-
         //! Current screen
         static QScreen *currentScreen();
 
@@ -272,16 +262,6 @@ namespace swift::gui
         //! Bring any modal dialog to front
         static void modalWindowToFront();
 
-        //! Parse scale factor if any
-        //! \deprecated using scaleFactor now
-        static double parseScaleFactor(int argc, char *argv[]);
-
-        //! Get the scale factor
-        static QString scaleFactor(int argc, char *argv[]);
-
-        //! Get a default scale factor
-        static QString defaultScaleFactorString();
-
     signals:
         //! Style sheet changed
         void styleSheetsChanged();
@@ -323,7 +303,6 @@ namespace swift::gui
         QCommandLineOption m_cmdWindowStateMinimized { "emptyMinimized" }; //!< window state (minimized)
         QCommandLineOption m_cmdWindowMode { "emptyWindowMode" }; //!< window mode (flags: frameless ...)
         QCommandLineOption m_cmdWindowSizeReset { "emptySizeReset" }; //!< window size reset
-        QCommandLineOption m_cmdWindowScaleSize { "emptyScale" }; //!< window scale size
         CStyleSheetUtility m_styleSheetUtility { this }; //!< style sheet utility
         bool m_uiSetupCompleted = false; //!< ui setup completed
         bool m_saveMainWidgetState = true; //!< save/restore main widget's state

src/gui/guiutility.cpp

@@ -797,7 +797,7 @@ namespace swift::gui
 
     QString CGuiUtility::metricsInfo()
     {
-        static const QString s("%1 %2 %3 | 80 chars: w%4 h%5 | 43 chars: w%6 h%7");
+        static const QString s("%1 %2 | 80 chars: w%3 h%4 | 43 chars: w%5 h%6");
         const QSizeF s80 = CGuiUtility::fontMetrics80Chars();
         const QSizeF s43 = CGuiUtility::fontMetricsLazyDog43Chars();
 
@@ -811,21 +811,7 @@ namespace swift::gui
             desktop = QStringLiteral("Desktop w%1 w%2").arg(sd.width()).arg(sd.height());
             ratio = QStringLiteral("ratio: %1").arg(mainWidget->devicePixelRatioF());
         }
-        return s.arg(desktop)
-            .arg(CGuiUtility::isUsingHighDpiScreenSupport() ? "hi DPI" : "-")
-            .arg(ratio)
-            .arg(s80.width())
-            .arg(s80.height())
-            .arg(s43.width())
-            .arg(s43.height());
-    }
-
-    bool CGuiUtility::isUsingHighDpiScreenSupport()
-    {
-        const QByteArray v = qgetenv("QT_AUTO_SCREEN_SCALE_FACTOR");
-        const QString vs(v);
-        const bool highDpi = stringToBool(vs);
-        return highDpi;
+        return s.arg(desktop).arg(ratio).arg(s80.width()).arg(s80.height()).arg(s43.width()).arg(s43.height());
     }
 
     void CGuiUtility::forceStyleSheetUpdate(QWidget *widget)

src/gui/guiutility.h

@@ -254,9 +254,6 @@ namespace swift::gui
         //! Some info about font metrics
         static QString metricsInfo();
 
-        //! Using high DPI screen support
-        static bool isUsingHighDpiScreenSupport();
-
         //! Forces a stylesheet update
         static void forceStyleSheetUpdate(QWidget *widget);
 

src/swiftcore/main.cpp

@@ -20,7 +20,6 @@ using namespace swift::gui;
 
 int main(int argc, char *argv[])
 {
-    CGuiApplication::highDpiScreenSupport(CGuiApplication::scaleFactor(argc, argv));
     QApplication qa(argc, argv);
     Q_UNUSED(qa) // init of qa is required, but qa not used
 

src/swiftdata/main.cpp

@@ -19,7 +19,6 @@ using namespace swift::gui;
 
 int main(int argc, char *argv[])
 {
-    CGuiApplication::highDpiScreenSupport(CGuiApplication::scaleFactor(argc, argv));
     QApplication qa(argc, argv);
     Q_UNUSED(qa)
 

src/swiftguistandard/main.cpp

@@ -20,7 +20,6 @@ using namespace swift::core;
 
 int main(int argc, char *argv[])
 {
-    CGuiApplication::highDpiScreenSupport(CGuiApplication::scaleFactor(argc, argv));
     QApplication qa(argc, argv);
     Q_UNUSED(qa) // application init needed