This seems related to the current discussion on views. A layer is a piecewise disjoint subset of objects (please correct me if I'm wrong here--I don't use layers that much) in which the object positions are fixed. A view (as I am proposing it) would be an arbitrary subset of objects in which the object positions are allowed (but not required) to vary. Effectively an independent diagram with the restriction that the included objects must be a subset of the "base" diagram.
I've been thinking, and I was wondering if it would cause anyone pain if we extended the current Dia view function to the description above?
It seems like I could do it so that the basic original view capability is preserved. There would probably be some additional interface complexity, but I think the end result would be more useful than current views.
> From: "Matthew J. Smith" <firstname.lastname@example.org>
> Date: 2003/08/12 Tue AM 09:49:11 EDT
> Hello all-
> As a Dia user, I just wanted to throw out one of my own observations.
> Currently, an object seems to reside in a single layer, and can have no
> interaction (for example, connecting lines) with objects in another
> I use layers all the time to show/hide the different components of my
> drawing. For example, an IT Environment diagram may have a physical
> network layer, a logical routing layer, a server layer, an application
> layer, etc.
> It would be very useful to me to have an object that can belong in
> multiple layers. In the above example, it would be great to have the
> firewall in all my layers, so that all objects can be connected. As
> well, I'd like to hide all layers except for the one I am interested in,
> and still have the firewall show up.
> I think the easiest solution would be to make layer membership a
> multi-value attribute of an object. A layer view would then abstractly
> be a query to find all the objects with the selected layer(s) listed as
> an attribute. This would also allow all objects to connect with all
> others, regardless of layer, since all objects could belong to some
> common "primary" layer.
> Would this type of functionality be useful to anyone else? Or, should
> I just re-evaluate my use of layers in diagrams?
> Thanks all,
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