Replace raster qbt logo with vector version

Add helper function for svg icons.

src/gui/about_imp.h

@@ -55,7 +55,7 @@ public:
         lb_name->setText("<b><h2>qBittorrent " QBT_VERSION " (32-bit)</h2></b>");
 #endif
 
-        logo->setPixmap(Utils::Gui::scaledPixmap(":/icons/skin/qbittorrent32.png", this));
+        logo->setPixmap(Utils::Gui::scaledPixmapSvg(":/icons/skin/qbittorrent-tray.svg", this, 32));
 
         // About
         QString aboutText = QString(

src/gui/mainwindow.cpp

@@ -160,11 +160,13 @@ MainWindow::MainWindow(QWidget *parent)
     // Setting icons
 #ifndef Q_OS_MAC
 #ifdef Q_OS_UNIX
-    if (Preferences::instance()->useSystemIconTheme())
-        setWindowIcon(QIcon::fromTheme("qbittorrent", QIcon(":/icons/skin/qbittorrent32.png")));
-    else
+    const QIcon appLogo = Preferences::instance()->useSystemIconTheme()
+        ? QIcon::fromTheme("qbittorrent", QIcon(":/icons/skin/qbittorrent-tray.svg"))
+        : QIcon(":/icons/skin/qbittorrent-tray.svg");
+#else
+    const QIcon appLogo(":/icons/skin/qbittorrent-tray.svg");
 #endif // Q_OS_UNIX
-    setWindowIcon(QIcon(":/icons/skin/qbittorrent32.png"));
+    setWindowIcon(appLogo);
 #endif // Q_OS_MAC
 
 #if (defined(Q_OS_UNIX))

src/gui/utils.cpp

@@ -30,6 +30,7 @@
 
 #include <QApplication>
 #include <QDesktopWidget>
+#include <QPixmapCache>
 #include <QScreen>
 #include <QStyle>
 #include <QWidget>
@@ -69,6 +70,20 @@ QPixmap Utils::Gui::scaledPixmap(const QString &path, const QWidget *widget, con
     return pixmap.scaledToHeight(scaledHeight, Qt::SmoothTransformation);
 }
 
+QPixmap Utils::Gui::scaledPixmapSvg(const QString &path, const QWidget *widget, const int baseHeight)
+{
+    const int scaledHeight = baseHeight * Utils::Gui::screenScalingFactor(widget);
+    const QString normalizedKey = path + "@" + QString::number(scaledHeight);
+
+    QPixmap pm;
+    QPixmapCache cache;
+    if (!cache.find(normalizedKey, &pm)) {
+        pm = QIcon(path).pixmap(scaledHeight);
+        cache.insert(normalizedKey, pm);
+    }
+    return pm;
+}
+
 QSize Utils::Gui::smallIconSize(const QWidget *widget)
 {
     // Get DPI scaled icon size (device-dependent), see QT source

src/gui/utils.h

@@ -49,6 +49,7 @@ namespace Utils
         }
 
         QPixmap scaledPixmap(const QString &path, const QWidget *widget, const int height = 0);
+        QPixmap scaledPixmapSvg(const QString &path, const QWidget *widget, const int baseHeight);
         QSize smallIconSize(const QWidget *widget = nullptr);
         QSize mediumIconSize(const QWidget *widget = nullptr);
         QSize largeIconSize(const QWidget *widget = nullptr);