Re: gEDA-user: Topics discussed at yesterday's Free Dog meeting (10.6.2005)

[John Luciani <jluciani@xxxxxxxxx>]

I placed the write-up of the PCB placement utility that was discussed
at last nights
Freedog in the "not-quite-ready" section of luciani.org.

http://www.luciani.org/not-quite-ready/not-quite-ready-index.html

(* jcl *)


On 10/7/05, Stuart Brorson <sdb@xxxxxxxxxx> wrote:
> Tonight's meeting started early because I needed to pick up some
> people at the airport later in the evening.  Three people came:  Ales,
> John, and myself (Stuart).  I am always suprised and gratified by the
> amount of interest these Free Dog meeting notes generate on the gEDA
> lists!  Hopefully, tonight's meeting will be as interesting to read
> about as it was to attend in person.
>
> Herewith, some of the topics we discussed, in no particular order.
>
>
> *  The gschem patches which draw "L" nets.  Ales had downloaded the
> patches, and built them on his machine.  He demonstrated the new net
> drawing style, and we all liked it.  Personally, I think this style of
> drawing nets is preferable to drawing individual, orthogonal segments.
> In particular, it makes it easy to connect two points which lie far
> away from one another on a diagonal.
>
> We all agreed to thank David Carr and Werner Hoch for this most
> excellent new feature!
>
> As an aside, most commerical schematic capture packages draw "L" nets,
> so this feature brings gschem up to the same standard as, say,
> ViewDraw.  One thing I noticed:  you can draw "L" nets through
> components.  In ViewDraw, nets will automatically avoid being drawn
> through components.  We discussed whether this was a feature or a
> bug.  John pointed out that one sometimes wants to draw nets through
> connector symbols, so the way gschem works now is a feature.
>
>
> *  Embedded picture support.  Ales demonstrated that gschem now allows
> you to place graphics in the drawing field, and also allows you to
> embedd the graphic directly into the .sch file.  We played with
> embedding and unembedding a .png graphic which Ales had on his
> machine.  Placing a graphic was very easy, and worked well.  You could
> resize the graphic, and gschem just "did the right thing".
>
> I asked what the feature was for, and we agreed that it would be nice
> way to put a company logo into a schematic.  I wonder if there are
> other uses?
>
> As for embedding and unembedding the graphic into/from the .sch file:
> Embedding worked great.  However, unembedding failed the first time
> around.  Ales looked at the code which supports unembedding
> components (which this new feature piggybacks upon), and we found a
> slight bug.  Ales fixed it in real time.  To me, this is a
> demonstration of the value of these user meetings: we can use them as
> light-duty hacking sessions!
>
> We all expressed mega thanks to Carlos for this way cool feature!
>
>
> *  John introduced another Perl utility for PCB.  His new utility,
> "pcb-place", will take a config file holding a list of components and
> desired positions, and place the components onto the PC board at the
> locations specified in the file.  Amongst other things, this utility
> is very useful for automatically placing large numbers of components
> arranged in regular patterns.  John presented an example in which he
> placed around 50 LEDs on a display board.
>
> His utility works by reading in an existing .pcb file, locating all
> the components listed in the config file, and the moving the
> components to the desired locations.  Making this work engendered a
> discussion about the PCB file format.  One issue raised which we have
> discussed here before is that in PCB a component's position is given
> in the component's header line, and when you translate a component,
> only the header changes.  However, when you rotate a component, the
> graphical elements *inside* the component are moved, even though there
> is a "rotation" attribute in the header.  Nobody could remember if the
> rotation attribute was only for the component's text, or if it was
> supposed to rotate the whole component, although John said that when
> he munged the rotation attribute, it didn't affect the text
> placement.  Could one of the PCB developers chime in here and clarify
> this?
>
> John's Perl placement utility will also add lines and vias to the
> component's footprint, which I think is an excellent feature for
> simplifying pin-escaping complicated parts.  He wants to add a few
> more features, and then will release it.  Watch his website!
>
>
> *  CD Installer:  Various people have reported problems getting the
> gEDA Suite installer to work successfully.  I am deeply concerned
> about this.  The biggest problem seems to lie with SuSE.  I am
> therefore going to build an installer test center in my gf's basement:
> I have about 1/2 dozen old scrap computers upon which I will load
> various distros (notably SuSE9.3 and FC4), and then try runing the
> installer on those distros to diagnose and correct the problems.  This
> process will take place over a few weeks (or more).  If you are
> suffering from problems with the installer, hang tight!  BTW:  Thanks,
> Ales, for the copy of FC4, and thanks in advance to the folks who are
> sending me copies of SuSE9.3!
>
>
> *  I had been playing with BRL-CAD for a little while, so I showed to
> the group what I had done so far.  Following Marvin's suggestion, I
> had started working through Vol 2 of the BRL-CAD documentation,
> although I hadn't gotten very far.
>
> I demoed use of the CLI to read in, display, and render a built
> object.  I had previously drawn the handheld radio given in the
> documentation, so I demoed that.  We moved it around and zoomed in and
> out.  Beyond that I hadn't gotten very far, so we didn't do much more
> than that.
>
> Some BRL-CAD comments:
>
>   --  It seems more like a visulation tool than a CAD tool.  For
>       example, I am at a loss about how to indicate dimensions, or
>       create a 2-D print of a 3-D shape I have modeled.  Has anybody
>       on this list figured out how to do this, or is it possible?
>
>   --  Driving BRL-CAD via the command line struck several of us as a
>       major annoyance.  I said that one normally must do lots of
>       command-line stuff anyway when creating dimensioned drawings, so
>       it didn't annoy me.
>
>   --  If BRL-CAD is indeed more about solid modeling and visulation
>       than about CAD, then the question is again raised:  What 3-D
>       mechanical CAD pacakges exist for Linux, commerical or
>       otherwise?
>
>
> *  After fooling with BRL-CAD, I ran QCad for the group.  The group
> opinion is that QCad's user interface is not very good, and requires
> far too much clicking on buttons on the left hand window.  No keyboard
> shortcuts exist for most operations, and certainly none exist for
> drawing.  This is a major misfeature, since it makes creating anything
> more than a trivial drawing a real pain.  We discussed how gschem
> allows one to move the mouse in one hand, and type keyboard shortcuts
> with the other. Everybody agrees that that is a major feature of
> gschem.
>
> We also observed that QCad's demo binary automatically closes down
> after 10 minutes of use.  Nobody liked that at all -- it's worse than
> nagware, although at least it gives you the option to save your work
> before it shuts down.
>
>
> *  We agreed to try PyCAD for the next meeting.  John told me that the
> latest PythonCAD rev is version 25, released last May.  The website
> is:
>
> http://www.pythoncad.org/
>
> My quest is to find  an open-source drawing program suitable for
> creating dimensioned drawings suitable for sending to a machine shop.
> Stay tuned to hear about what we think about PythonCAD!
>
>
> *  An aside:  I mentioned interest in Linux-based CNC software.  In
> particular, I have been following the "Enhanced Machine Controller"
> (EMC) list for a while.  Here's a link:
>
> http://www.linuxcnc.org/
>
> Other CNC links courtesy of John:
>
> 80/20 is at    http://www.8020.net
> Rockler is at  http://www.rockler.com
> Machinist Workshop is at http://www.homeshopmachinist.net/index.cfm
>
> Perhaps at some future FreeDog we will have a longer investigation of
> this kind of software.
>
>
> *  Back to gschem.  Ales is thinking about creating a "newbie mode"
> for gschem.  Newbie mode will offer more help to the new user, telling
> him what to do with each step of using the program.  We discussed
> whether newbie mode should be on by default, run one for the first 20
> sessions and then go away, etc.  It will be configurable, and will
> likely be an option in the gafrc.
>
>
> *  Another gschem topic:  There is some interest in a version of
> gschem which doesn't run the GUI.  This feature would be useful for
> scripted applications.   Ales is going to post a script that demos
> an alternative method (virtual buffer?)
>
>
> *  We talked about what to put on the gEDA Wiki.  Besides Ales' FAQ,
> here are some suggestions:
>
>   --  Link to Bill Wilson's excellent tutorial.  We discussed whether
>       it should just be a link, or perhaps take his stuff and wiki-ize
>       it.  Ales wants to put a link since Bill did such a nice job
>       with formatting, and Ales thinks preserving the formatting will
>       be difficult with the Wiki.  On the other hand, I think that
>       wiki-izing the tutorial will enable others to add to and improve
>       it (even though it's already excellent).
>
>   --  This idea led to another tutorial which I wrote a while ago and
>       shared privately with a small circle of readers.  I wrote the
>       tutorial for a glossy magazine, and submitted it.  It was
>       accepted, but they haven't done anything with it.  Since I
>       haven't signed over ownership yet, I can pull it from them and
>       stick it on the Wiki.  This would obviate the need to wiki-ize
>       Bill Wilson's tutorial, and would provide another gEDA tutorial
>       for newbies.  I promised to pursue this.
>
>   --  I will also create a graphic showing the design flow to create a
>       PC board, starting from gschem, and going through PCB.  Expect
>       to see this on the wiki soon!
>
>
> *  Windoze version of gEDA/gaf.  Ales said that he would spin a
> Windows version of gschem as soon as he (or somebody else) replaced
> the custom file browser with one build using stock GTK widgets.
> Hackers -- if you're looking for a gEDA project, this may be simple
> enough to get your feet wet with the project!
>
>
> *  GEDA project manager.  The current project manager, geda, is broken
> and unsupported.  Personally, I think having a working project manager
> would be a good thing, particularly becase so many newbies try using
> the suite by typing "geda" at the command line.  Right now,
> unfortuantely, they are likely to get a segfault when starting geda,
> which is a real turn-off.
>
> We discussed whether it was better to fix the existing program
> (written in C), or to just write something new from the ground up.
> Something new could be written in Python (my suggestion).  This makes
> sense because the purpose of the project manager is to present a GUI
> to the user, invoke various the various programs used in the design
> flow, and keep track of various project files.  This type of
> application naturally lends itself to a scripting-type language,
> instead of C.  As for scripting languages, Ales threatened to
> write the project manager in Scheme.  :-)
>
> However, before doing a rewrite, it would be a good idea to look more
> closely at geda to see if it can be easily fixed.  I belive that its
> problem is just that it hasn't kept up with changes to the GTK API
> (and perhaps a few other issues).
>
>
> *  John mentioned that he still wants to do a gEDA 200K (200 km) bike
> ride from Boston to New Hampshire!  Both Ales and I are a little too
> out of shape for that. (Although I ride, John wants to average between
> 15 and 20 mph for the whole ride, which is very strenuous.)  Anybody
> else on this list who bikes and wants to take John up on the offer?!!?
>
>
> *  Finally, responding to Ales' question, we talked about Google stock
> and why it was so high.  Personally, I think it is a bubble.  Google's
> business model is based upon selling advertising.  However, ads on
> television reach zillions of times more people than ads on Google
> since more people watch TV than do anything with computers.  Also, for
> the small percentage of people who are computer & Google users
> (including readers of this list), who every actually looks at the
> Google ads?  Anybody here read them?  I rarely do.  On the other hand,
> TV ads are inescapable.  Despite this, the stock prices of TV network
> companies are in the toilet, while Google is flying high.  To me, this
> makes no sense. Others may have a different opinion.
>
>
> After 2 1/2 hours of conversation, we broke up.  Thanks to John
> Luciani who e-mailed me a list of topics we discussed -- it helps to
> jog my memory about all the interesting subjects touched upon during
> the course of the evening!
>
> Your FreeDog correspondent,
>
> Stuart
>
>
>


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