Re: Re: gEDA-user: gschem BUS status

[sdb@xxxxxxxxxx (Stuart Brorson)]

> I would like to add part (.p) support and some layout rules. I am still
> digging through how gschem is all put together (and learning scheme).

You might find this drawing useful:

http://www.brorson.com/gEDA/gEDA_Structures_20050108.pdf

It shows how a typical schematic's datastructures are put together in
gschem.  It is component and attribute centric.  I created it by
studying the definitions in libgeda/include/struct.h, and by playing
around with gschem running within gdb.

The datasturctures used to create the netlist are different.  In
particular, the structure which represents a connected net (which is
built from a collection of individual net segments) is constructed by
gnetlist while it is doing its work.  I don't have an equivalent
drawing of it.  Perhaps some day I will create such a drawing.  First
I must understand how gnetlist creates this structure. . . .

Here's a bunch of notes I made while writing gattrib.  Maybe they will
also be of use?  

http://cvs.seul.org/viewcvs/viewcvs.cgi/eda/geda/devel/gattrib/NOTES?rev=1.3&view=markup

Again, the notes are component and attribute centric, but might be of
use while you try to  understand gschem and libgeda.

Stuart