gEDA: pcb generic footprints, real pin names

[Dan McMahill <dan-at-NOSPAMmcmahill_dot_net>]

At some point I seem to recall someone asking about getting pinlabels 
from gschem into the pin name in pcb when using a generic footprint like 
  0603 or TQFN68_10_EP.

Just for kicks I added an action to pcb which lets you change the pin 
name for a given refdes/pinnumber.  Its not committed yet, need to add 
some checks and undo to the code.  I also hacked together a gnetlist 
backend which will produce a file full of pcb actions which will set all 
fo the pin names.  So the flow is something like:


gschem myschematic.sch
gsch2pcb myschematic.prj
gnetlist -g pcbpins -o rename.cmd myschematic.sch
pcb myschematic.pcb

and then in pcb

:ExecuteFile(rename.cmd)

It's a hack in the sense that there is yet another (two actually) manual 
steps in the forward annotation procedure.  Its slick in another sense 
because gnetlist/gschem don't need to know anything about PCB's internal 
file format.  It communicates what it wants done in a fairly 
straightforward way by directly telling PCB "ChangePinName(U1,1,IN+)" 
and things like that.

I'm wondering if gsch2pcb should perhaps be modified to automatically 
run the "gnetlist -g pcbpins .." part and give you a message which says
to either run pcb with the flag that will execute the actions file on 
startup or tell you the action to execute once pcb is started.

Anyone see a reason to not commit gnet-pcbpins.scm (the gnetlist backend)?

The pcb action should be ok once I fix the undo stuff.

-Dan