gEDA-user: A few questions about gschem, gnetlist, and gspiceui/ngspice

["Yamazaki R2" <yamazakir2@xxxxxxxxx>]

   Hi all,
   Let me just say that the gEDA suite is pretty robust for being an open
   source project. For the most part I am happy with it and really
   appreciate the work that's been put into this project. It's great EDA
   option for the hobbyist as well as the professional. Now, I have a few
   questions/issues that I can hopefully get cleared up:
   1. The first thing I want to understand how the gnetlist scheme works
   for the spice scheme (gnetlist -g spice). When I run this command,
   what scheme backend files are processed? Only gnet-spice.scm? Or is
   any other scheme processed along with it? The reason why I ask is
   because when I take a look at gnet-spice.scm it seems to be getting
   some variables from somewhere else, as in the file doesnt seem
   self-contained.
   The reason why I ask is because I was interested in editing the way
   the netlister works. I created a 3 terminal nmos and pmos symbol and I
   want to either hardcore a implicit bulk connection into the netlister
   scheme or create a symbol attribute that specifies the bulk connection
   in it, maybe using the net= attribute. When looking at the
   gnet-spice.scm file, it doesnt show where its getting the number of
   pins for mosfet devices. The way I was going to go about it was change
   the number of pins to 3, then print the last net (the bulk) as a
   netname thats hardcored.
   2. I'm having a few issues with gschem. As of the current version, is
   there a way make filled shapes for symbols that aren't
   squares/circles? Such as a filled triangle? If not, does any
   development version have this feature? Another issues/annoyance I'm
   having with gschem is that the graphical interface inside the
   schematic is kinda buggy. For example, if I route a net, then delete
   it, the grid dots don't reappear until I either move the viewing plane
   or zoom in/out. Is this how it's suppose to work or do I not have my
   graphics library set up right? Another issue with gschem, is there
   planned support to actual font rendering at some date rather than each
   letter being it's own symbol? The reason I ask is because the way it's
   setup right now causes the fonts too look garbled/unreadable if you're
   not zoomed really far in.
   3. In GSspiceUI, why don't transistors show up in the device list? Do
   I not have it setup right or is this intentional? Also, why is the
   option to probe current grayed out when I choose ngspice as the
   simulation engine? Also, what is the proper probe syntax in ngspice to
   probe drain/source/gate current in a mosfet? Also
   collector/emitter/base current in a bipolar? Another (I think) bug in
   GspiceUI is the fact that it rounds the output voltages/current too
   much where when you plot it in gwave the granularity is bad. For
   example It's impossible to graph voltages in the 10s of millivolts
   because it sounds lots of steps as the same number. Try an input of a
   5mVpp sine wave then plot it in gwave and see what I mean.
   4. Speaking of gwave, how do I add the voltage/current/time/frequency
   access to the plots? What about grid lines?
   Thanks all


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