Most of the documentation in gtkmm has been copied from GTK (formerly GTK+). The description of Gtk::Layout is more or less a copy of the documentation of GtkLayout. I don't understand why it's said that the scrollable area is infinite. As far as I know all widgets have finite size. The size can be large, much larger than a normal screen, but not infinite. I think you'd better ask the GTK people. They don't use gnome mailing lists any more. Their discussions have moved to discourse.gnome.org.Hi,
I am learning Gtk+ with gtkmm and my goal is to create a node based interface for visual programming. I started a thread on the Gnome discourse : https://discourse.gnome.org/t/project-guidance-node-based-ui/
Basically what I want is to have my custom node widgets on a "canvas" so I can be able to move them by dragging them. If anyone knows Blender's node editor, it should also be possible to pan with middle mouse button and also zoom.
The Gtk::Layout component seems the right one when it comes to put nodes at specific location on the interface. I also want to draw a custom grid so this so the documentation seems adapted :
Infinite scrollable area containing child widgets and/or custom drawing.
Now the "infinite scrollable area" concept interest me because I want to be able to move on the node tree. The documentation says that I can just put the layout into a Gtk::ScrolledWindow and it supports scrolling natively.