From mjl@dino.ph.utexas.edu Fri May 27 05:02 CDT 1994
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From: Maurice LeBrun <mjl@dino.ph.utexas.edu>
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Subject: Some comments on 4.99g
To: plplot-list@dino.ph.utexas.edu
Date: Fri, 27 May 94 4:32:26 CDT
Full-Name: Maurice LeBrun
Cc: mjl@dino.ph.utexas.edu
Mailer: Elm [revision: 70.85]
Status: RO

Just some varied comments about this last release.

This release (PLplot 4.99g) was very long awaited, and very draining.
There have been several new capabilities that I thought were too crucial
to wait any longer before adding them, as well as many minor improvements,
bug fixes, and user-contributions.  There are a lot of energetic users-of
and contributers-to PLplot.  A bit to my surprise, I might say.  (But
then, recently when I talked to Sze Tan, the original author, he said the
same thing..)

No doubt there will be some difficulties encountered with this release.
There may have to be a bug fix release before long to fix problems, so
please let me know of difficulties.  It might help to post them to the
mailing list so that other people don't have to experience the same.

This is the last big release before 5.0, the rest I hope are relatively
minor updates.  With 5.0, we aim for (a) most known bugs to be killed, (b)
all capabilities we've been working on to be finished, (c) all significant
capabilities be documented, and (d) the package tested on all platforms
listed as "supported".  We are approaching this goal, but are a little
ways from it yet.  However you may still get your chance to help out :-).
More on that later.

Some comments on the new capabilities:

A big newbie is the Tcl-DP driver.  Fixes some of the inherent problems
in the TK driver send mechanism, and is distributable across a network.
It really works, I've tried it (for some configurations at least).
Nothing like zooming in on a plot at workstation speeds when the renderer
front-end is running on a machine half the world away (yes, I've even
done it between Texas and Japan).

Lots of cool improvements to the TK interface.  Check out the color
palette manipulation tools.  Certain menus have keystroke equivalents now
(e.g. hit 'z'), making simple operations much nicer (thanks, Dave, for the
suggestion).

Support for direct usage of the plframe widget as a Tcl/TK extension.
This is very important since Tcl/TK, especially when taking all the cool
extensions into account, is *THE* way to program X-based applications
(IMO).  Sophisticated user interfaces to scientific codes under X, using
the PLplot widget (among others) are just waiting to be built...

Color map 1 support -- this is designed to enable the type of continous
color plots you can get in other graphics packages (e.g. I'm thinking of
NCSA Ximage) but in a more flexible way, allowing intuitive modification,
and display on a number of devices.  This capability comes in through the
new color palette -- cmap1, and you take a look at x16c to see the effect.
Preferably using multiple color (supported) devices, and for the best
effect using the TK or DP driver, playing with the color palette using the
new menu options.  Thanks again to Wesley Ebisuzaki for contributing
"plshade()", the function doing the shading here.  Note: plshade is the
best way for limited number of colors, but for a larger number of colors
(and grid points) a different algorithm would be optimal, something that
is more discrete.  At 0th approximation, you might try a function that
just fills each grid cell with a constant color.  Suggestions appreciated.
Also, the TK driver right now does not proper clip polygons (on zooms),
because the algorithm to do so hasn't been implemented.  Any interested
parties?

Work on the updated manual is underway and so far it's looking pretty good...

--
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]

