From mjl@dino.ph.utexas.edu Wed Oct 27 17:11 CDT 1993
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From: Maurice LeBrun <mjl@dino.ph.utexas.edu>
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Subject: Some comments about plplot 4.99d.
To: plplot-list@dino.ph.utexas.edu
Date: Wed, 27 Oct 93 17:08:53 CDT
Full-Name: Maurice LeBrun
Cc: mjl@dino.ph.utexas.edu
Mailer: Elm [revision: 70.85]
Status: RO

I thought I'd mention a few other things in association with this latest
release.  There may be a smaller release before long, to address those
(hopefully minor) problems that arise.  Then I will take a break from
plplot development for a short while, and after that my major push will be
to update the document, a few more enhancements, and slow down a bit.

The TK driver was a tremendous push, but I expect it to be worth it.  It
has the basic functionality that I've always wanted, along with a huge
potential for customization.  It is my intention that people can build
arbitrary Tcl/TK applications that just happen to use plplot widgets to
plot into.  I plan to construct at least one demo of how to do such a
thing, and it will be interesting to see what kinds of variations people
come up with.  Tcl/TK programming is so easy that there should be lots (I
can't believe I was actually considering doing a Motif-based driver).
Writing a widget, on the other hand, is hard work, but now that's more or
less history.

Also, as I constructed the Tcl/TK driver I tried to add the required
increases in functionality to plplot in a rather generic way.  The stuff
you would ordinarily use a GUI for can typically be handled from the
command line in fact -- like page layout, zooms, and orientation
(independent of the output driver).  This is because of the new driver
interface functions that sit between the library proper and the driver.
They are located in plcore.c if you are interested, and do 4
transformations so far -- orientation (you can even rotate by a fractional
amount, but I never bothered making it come out perfect! :-), altering the
window into plot space (zoom), altering the window into device space
(page layout, good for adding margins), and global device coordinate
transformation (good for making page dumps to an arbitrary device).
Other windowing drivers should be able to use these facilities without
too much trouble.  Eventually I hope to intercept other commands at
the interface layer, and decide what to do based on the intelligence
of the driver.  This might be used to handle device dependent fonts,
hardware color fill, and so forth.

At this point, I'm feeling the need to release the package in a more
"official" way than I have in the past.  So my main priority will be to
bring the documentation up to sync with the rest of the package.  I would
also like to accomplish the first 4 or so things on my 'ToDo' list, and as
it should involve about 1/10 of the effort of the original TK driver (I
hope :-) expect it to happen in a much shorter time frame than the 8
months or so this release has taken.  I'll probably introduce some
compatibility problems at that time in an effort to consolidate, but after
5.0 will be very careful about breaking old software.

In another change, I would like to ask for volunteers to maintain versions
of plplot for specific platforms.  These people could get prerelease
versions in order to make whatever fixes are needed ahead of time.  We are
most likely to have the package be up-to-date on the following systems:
HP-UX, Linux; less likely on the following: SunOS, AIX, Unicos, Super-UX,
Amiga, and maybe not at all on any others.  It would be good for someone
to put in shared library support for any system that supports them (so far
I've only done it under HP-UX).  I am gradually moving away from
supporting the Amiga driver so could use some help here.  Geoff has
abandoned the DOS drivers and is leaning away from supporting the OS/2
driver, so here again target platform developers are needed.

--
Maurice LeBrun    mjl@dino.ph.utexas.edu
Institute for Fusion Studies, University of Texas at Austin

Faire de la bonne cuisine demande un certain temps.  Si on vous fait
attendre, c'est pour mieux vous servir, et vous plaire.
                                [menu of restaurant Antoine, New Orleans]

