the GtkIconSource specifying the icon to render
the size to render the icon at. A size of (GtkIconSize) -1 means render at the size of the source and don't scale. [type int]
a newly-created GdkPixbuf containing the rendered icon. [transfer full] Since 3.0
Warning gtk_render_icon_pixbuf has been deprecated since version 3.10 and should not be used in newly-written code. Use gtk_icon_theme_load_icon() instead. Renders the icon specified by source at the given size, returning the result in a pixbuf.