On Wed, 23 Oct 2002, Mike Garnsey wrote: > I have been experimenting with doing something > like that, too. Why? I want to be able to have a set > of "idiot-proof" objects for a Dia user to lay out a > computer network diagram. For example, the user > shouldnt be able to connect something like a PC object > directly to something like a microwave transmitter > object. Or, a USB printer object shouldnt be > connectable to a 10BaseT repeater object.
I see. I suppose idiot-proofness is good, as long as it doesn't restrict what people want to do. > I had pretty good success with the following (crude!) > approach: > 1. hack diagram_update_connections_object() > to force a redraw of the connected object > > 2. for specific objects that you want restricted > connection functionality, add code to the > DrawFunc routine to analyze (and disconnect > as appropriate) the objects that are > connected. > > Definitely not ideal (DrawFunc gets fired for a > variety of reasons), but it worked. The right place to add a checking call would be in layer_find_closest_connectionpoint() in app/diagramdata.c. Problem is, that loop goes over all objects in a layer, so we can't afford to spend a lot of time there. Well, we can keep it within the if, that'll cut out most of it. And instead of adding code to DrawFunc, a new object func should be defined for it. -Lars -- Lars Clausen (http://shasta.cs.uiuc.edu/~lrclause)| Hårdgrim of Numenor "I do not agree with a word that you say, but I |---------------------------- will defend to the death your right to say it." | Where are we going, and --Evelyn Beatrice Hall paraphrasing Voltaire | what's with the handbasket? _______________________________________________ Dia-list mailing list [EMAIL PROTECTED] http://mail.gnome.org/mailman/listinfo/dia-list FAQ at http://www.lysator.liu.se/~alla/dia/faq.html Main page at http://www.lysator.liu.se/~alla/dia
