Step 4:
- Update the MainWindow class, to use all the new possibilities of the
framework:
- multi-selection of items in the scene,
- activate the use of the items popup-menus.
- Add Qt Script possibilities.
- New actions in the "View" menu: "Look at", copy-paste of camera
positions, select background color.
- New action "Reload item", to reload an item if it was loaded from a
file.
Laurent Rineau