Re: gEDA-user: General Layers questions

[DJ Delorie <dj@xxxxxxxxxxx>]

> IMHO, vias should be layers as well, with attributes that tell to which
> conductive layers they connect. 

We've talked about this before, too.

The best design we came up with was to create "composites", where a
stackup was built from sub-stackups etc, and each composite contained
one or more layers combined with an "outline".  The outline included
any holes, such as vias.  So a via at the top-level board had a hole
that applied to all layers, but if you put the via at some lower
level, in a composite that contains a subset of the physical layers,
you got a blind/buried via.  This also allowed us to represent flex
cable, where the "outline" of each layer might be different from other
layers.

This design applied well to the process of driling then assembling PCB
layers, but didn't apply well to partially re-drilling an assembled PCB.
I.e. it didn't support this via combination:

--+ +--------------
  | |
  | | -----+ +-----
  | |      | |
--+ +---   | |   --
           | |
-----------+ +-----


_______________________________________________
geda-user mailing list
geda-user@xxxxxxxxxxxxxx
http://www.seul.org/cgi-bin/mailman/listinfo/geda-user