Re: objects graphics?

[davidf(at)dfanning.com (David Fanning)]

Pedro Velez-Belchi (pedro.velez@ieo.rcanaria.es) writes:

>     I have been using IDL for long time as well as matlab 5.x. Now that
> is possible to use object graphics in IDL i would like to learn it. My
> experience in matlab tell me that OG is really easy (handles is called
> in matlab), but, I have looked to some OG codes (as Xplot from David)
> and it seems really hard. It seems that IDL OG are really much more
> complicated as the analogous in matlab. Does anybody have the same
> feeling or just I am doing something wrong?

I wouldn't say it is hard. But it is nearly impossible to
figure out from the documentation that normally comes with
IDL. :-)

And it wouldn't really be so hard to figure out, I
guess, if you could just forget everything you know
about IDL direct graphics and come at it as a complete
novice. What is really hard about it is trying to compare
it with what you already know. And that, I can tell you
from personal experience, is a disaster.

The object graphics system is at a very low level. I
think that more than anything else is what scares people off.
You do have to create and put together a lot of graphic
"atoms" to get something as simple as a line or surface 
plot. I've almost got a couple of chapters done that 
explains this whole process in considerable detail. I
thought I would release those chapters in PDF format
ahead of my whole book. 

In the meantime, you might want to take one of the IDL
Advanced Programming Courses. I think they are very good
and certainly will take much of the mystery out of object
graphics for you. In fact, I'm teaching a couple of these
courses in Europe next month: March 27-30 in the UK, and
April 4-7 in Copenhagen. Let me know if you want more 
details.

Cheers,

David

-- 
David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: davidf@dfanning.com
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