Using python for a CAD program

[63q2o4i02 at sneakemail.com]

Hi, I'm interested in using python to start writing a CAD program for
electrical design.  I just got done reading Steven Rubin's book, I've
used "real" EDA tools, and I have an MSEE, so I know what I *want* at
the end of this; I just have never taken on a programming task of this
magnitude.  I've seen that some are using python as a utility language
for existing CAD environments, and I've also found some guy who's
writing a 2d drafting tool with python, which is cool.  I've been
playing with python recently and so far have a SPICE parser
half-written (it'll do production rules, but no syntax trees yet...)
I'm wondering if the python experts can provide some opinion on
python's efficiency/utility in the following areas, and perhaps where
some things will need to be in C++ and/or pyrex:

1.  Databases.  I don't mean sql type database, but design databases,
which contain all the components for any given design, including
schematics, layout, simulation parameters, etc.  I'm not concerned
about python's ability to do fancy data structures, but I'm wondering
how it'll go in terms of efficiency when things get really big.  If the
alternative is home-brewed C++ linked-lists, attributes, arrays, binary
trees, memory management, etc., it looks like python's ability to do
all this neatly without all the bugs waiting to happen if I did this
myself are well worth the efficiency loss that may result from its
uber-generality.

2.  GUI.  Yes, I know you can do guis with qt, gtk, tkinter, etc.  I'm
talking of fancy guis that do alpha blending, animations, nice
shading/gradients, etc. in a quick, smooth, and slick way, such that
moving a scroll bar or jiggling the mouse yields fast game-like
response time, and which gives this program the feeling that you're
actually in the 21st century... ie this is an *interactive*
environment, and I f***king hate crass-hatching, so real colors is a
must.  Can this be portable between linux and windows?  Is it possible
to "do the whole thing" in opengl, even the 2d stuff?  I guess I dont
know enough about guis here.  My fear is that my app will turn into
x-hell if I try to do more than 8-bit colors in linux, with flashing
background windows and complaints from the server about bit planes.
Maybe I need to play with linux a bit more from the development side
before commenting on this, since I get the feeling I'm working on old
information here...

3.  Computational stuff.  I imagine the really heavy computing needs to
be done in c++, especially if I'm stupid enough to write my own
simulator, which my brain seems to want to do (I'm imagining a small
homer simpson brain with a mind of its own telling me what to do...).
But what about other things like rules and constraints about layout,
routing, compaction, undo/redo, etc?  These aren't really
computationally expensive, I don't think, but do munge about quite a
bit with the database.  Is it likely I'll write something faster in
C++?  (answer: no).

4.  Programmability.  I imagine this is a slam-dunk, relatively
speaking, to have a python interpreter as part-and-parcel of the design
system.  But how do I customize the command window to do custom things
like adding special shortcuts (eg '?' brings up help, or help on
commands a la Matlab), or making an API into the CAD program?  I'm not
sure conceptually how to merge an embedded python interpreter into the
rest of the CAD program in an intelligent way, so some stuff is
exposed, but not all, and which interacts dynamically with the
graphical portion so that, for instance, context-sensitive help is
available in the console window, or so you can access information about
the currently selected object, or so you can do stuff from the command
line that is based on your current graphical context.

5.  Threads and parallelism.  One of the things about this is that I'd
like there to be some real-time simulator running so when you change
the values of parts, the output changes, and I'd like to be able to
take advantage of mulitple processors, or dual-core, or whatever.  I've
seen fake multi-threading in python (read about it, but I haven't done
it), but that doesn't really use any extra cycles from a separate
processor.

So why am I thinking about this?  I've used a few  "real" CAD systems,
and from using them, it's obvious the modus is to kludge shit  together
over 20 years and screw the user experience.  So basically I'd like to
take over the world with my nifty new python-based cad system because
it's so beautiful and fun to use, and so flexible that my time to
market for any given new idea is 5x shorter than the existing tools.

Any comments on the above from people who've actually written stuff
would be greatly appreciated! :)

thanks
ms