On Wed, 2005-01-26 at 17:40 +0100, Akos Maroy wrote: > Hi, > > I'm trying to draw a PNG image, which has some transparent parts, by > calling Gdk::Pixbuf::render_to_drawable(). > > The documentation of this function says that this call will not honor > transparency, or that's how I understand the following: > > > "Note that this function will ignore the opacity information for images > with an alpha channel; the GC must already have the clipping mask set if > you want transparent regions to show through." > > > now, how would I generate the clipping mask for a transparent PNG image? > I see functions like Gdk::Pixbuf::render_pixmap_and_mask(), but I just > don't know how to use them.. (and there's no documentation for them > either :(
Gdk::Pixbuf::render_to_drawable_alpha(...) has a parameter that lets you set the threshold for the alpha. Basically your only option is on/off, no alpha blending-ish rendering is supported ATM. Basically render_to_drawable_alpha uses the threshold and the alpha channel to create the GC clipping mask, then renders using that, I believe. Regards, Carl _______________________________________________ gtkmm-list mailing list [email protected] http://mail.gnome.org/mailman/listinfo/gtkmm-list
