graphics issues

[address@hidden]

Hi all

The last some days, I've read the discussion about graphics 
issues...
maybe this can help: 
http://users.physik.tu-muenchen.
de/gammel/matpack/html/matpack_frame.html

matpack includes a 2d/3d graphics-engine...
but I haven't time to have a look on it...
Michel


----Ursprüngliche Nachricht----
Von: address@hidden
Datum: 03.10.2006 04:51
An: "Joe Koski"<address@hidden>
Kopie: "octave maintainers mailing list"<address@hidden>, 
"John W. Eaton"<address@hidden>
Betreff: Re: graphics issues

Joe Koski wrote:
> on 9/29/06 11:38 AM, John W. Eaton at address@hidden 
wrote:
>
>   
>> On 29-Sep-2006, Shai Ayal wrote:
>>
>> | While OpenGL will take care of all the 3D stuff, you still 
have all
>> | the "graph" things to take care of -- axes, tics, legends, 
titles
>> | etc... All are "trivial" but with many small annoying details 
(auto
>> | axes limits and ticks is quite hard IMHO). this is quite a lot 
of
>> | work. octplot is under development for more than 2 years 
(although
>> | it's not very intensive development) and these things are 
still far
>> | from prefect
>>
>> I agree that these little details, while each may seem like a 
simple
>> problem, add up to a major headache, especially given that the 
code
>> already exists in other places (gnuplot, plplot, NCAR graphics, 
etc.).
>>
>> My preference would be to use some existing code if at all 
possible,
>> but I don't know where to find something that is relatively easy 
to
>> use and not closely tied to a specific plotting package.
>>
>> jwe
>>
>>     
> A couple of points. I have the post-processor called smokeview 
for the NIST
> FDS code (see http://fire.nist.gov/fds/ ). It is an OpenGL 
application and
> runs on my Mac (without X11) with 3D displays that I can rotate, 
change the
> viewpoint, etc. without the delays or "inertia" that feel when 
I'm using
> other applications. Whether a graphics language can run natively 
on many
> platforms, including Windows and Macs, should be a major 
consideration.
> Apparently OpenGL has that capability, but I'm no expert, so 
maybe someone
> can comment on that.
>
> Second, the plplot folks have been very active lately, enhancing 
the
> package, so maybe plplot should be reevaluated, especially since 
there is
> already an octave binding included in the plplot distribution. 
The plplot
> folks are adding a wxwidgets driver. Is that tied to X11? The 
"widgets" in
> the name sure sounds like X11 is involved. What is the potential 
impact of
> wxwidgets on octave? I did play with octave/plplot a year or two 
ago, and
> found myself going back to gnuplot. Back then, plplot's main use 
was for
> salvaging the graphics on old legacy codes that had outlived 
their
> commercial graphics interface (remember DISSPLA?). Maybe now it's 
different.
>   

The soon to be released gnuplot 4.2 also has a wxWidgets terminal. 
I've 
tried it and it looks great (anti-aliased fonts and lines). I've 
been 
ready to give up hope for gnuplot, but this has convinced me to 
give it 
a second chance. wxwidgets is a cross-platform toolkit that 
supposedly 
runs natively on each supported platform, so presumably this means 
X11 
is not required to run it on Mac or Windows. I tried plplot once 
or 
twice but I finally gave up on it because it found it unstable on 
Linux.

With the new gnuplot release, it should not be too difficult to 
add 
better control over line width, color, etc. It still seems like 
the 
shortest path to a working backend to the object-graphics frontend. 
On 
the other hand, the real weakness is that gnuplot is a standalone 
program, rather than a library. The main problem I see with this is 
that 
data is transfered via file I/O, rather than simply using on data 
that 
is already in memory. The new version helps a little bit because 
binary 
data transfer is now supported, but it's still suboptimal for 
large 
amounts of data. The other big benefit of the new gnuplot is 
support for 
images, so that the image display routines can be displayed as 
plots 
with the axes and titles and all.

Anyway, I don't mind dumping gnuplot when something that can 
replace it 
supports all of the necessary features, but I agree with John that 
for 
now updating the gnuplot interface seems the quickest way to get 
what 
people want. I'm happy to be proven wrong by the OpenGL 
supporters.

-Quentin