Am Mittwoch, den 06.05.2009, 13:42 -0400 schrieb Christopher Harvey: > I want to extend Gdk::Region. I noticed it didn't have a virtual > destructor. I REALLY need to be able to extend it, otherwise I'll end up > with random functions floating around all over the place.
A virtual destructor probably won't be of much help, as Gdk::Region implements value semantics so you can't really add any data to it and use it polymorphically. If you only want encapsulation but don't like the idea of inheriting from a class that doesn't have a virtual destructor, you could instead make Gdk::Region a member of your custom class. > Basically I want to create a region class that can build itself from > complex input, then be used as a normal region. I don't know what you are working on; however, from your other mail it sounds as though you are trying to reduce the amount of drawing done in your expose handler. If so, it's probably a good to check whether complicated regions will actually improve matters on average. With Cairo clipping, it can easily happen that figuring out the clipping region actually increases the overall processing time. It depends on what and how much you are drawing, I guess. > Can we make this class extendable? It seems like a nice feature for a > widget library especially. Adding a virtual destructor probably wouldn't be a big deal here (but not until the next ABI break!). However, I'm not sure it will be of any use, given the value semantics. --Daniel _______________________________________________ gtkmm-list mailing list [email protected] http://mail.gnome.org/mailman/listinfo/gtkmm-list
