[35_3] dark mode for svg icons on Windows/Linux/macOS

Co-authored-by: 沈浪熊猫儿 <[email protected]>

src/Plugins/Qt/qt_picture.cpp

@@ -99,7 +99,11 @@ qt_load_icon (url file_name) {
 #ifdef OS_MINGW
     return QIcon (qt_load_svg_icon (svg));
 #else
-   return QIcon (to_qstring (as_string (svg)));
+  if (occurs ("dark", tm_style_sheet)) {
+    return QIcon (qt_load_svg_icon (svg));
+  } else {
+    return QIcon (to_qstring (as_string (svg)));
+  }
 #endif
   } else {
     return QIcon (as_pixmap (*xpm_image (file_name)));
@@ -388,6 +392,11 @@ qt_load_svg_icon (url file_name) {
   QPainter painter (pm);
   renderer.render (&painter);
 
+  if (occurs ("dark", tm_style_sheet) && may_transform (file_name, *pm)) {
+    invert_colors (*pm);
+    saturate (*pm);
+  }
+
   QPixmap icon (pm->size ());
   icon.convertFromImage (*pm);
   return icon;