Celestia Forums

This is my second attempt at Celestia .cel scripting. While .cel scripts
are easy to learn and write, they are really not well suited for a more
complex projects so, as is the case with my last .cel script(s), this one
is 100% computer generated
This time I wanted to build a perl script that would generate a complete
Galileo scientific mission overview (in Jupiter orbit) based on a data it
finds on the official Galileo webpage. You just give it a link to a Web page
and it builds a .cel script (no human editing/copy-pasteing required)
If you like, you can download a alpha (proof-of-concept) version of the
output from:

http://student.fizika.org/~dsvilko/celestia/galileo-jupiter.cel

Tell me what you think. The script is quite long (381 events * 5 seconds
each = a little over half an hour!) so I don't expect you to sit through
the whole thing (hear that Don?)

TODO list:
- more inteligent timerate manipulation (I would really like a sugestion on
how to solve this one)
- zoomed-out orbital views
- scientific summarys before or after every orbit (also pulled from the web)
- realistic instrument FOV (does SSI have a consant focal length?)

If you have any other sugestion, let me know.

DoS

I think that your script is a very good start. With a little refinement (FOV adjusting, etc.), and some careful "event selection", it will be much more enjoyable.
Now, I am not sure what you meant with intelligent timerate manipulation, but some time ago I wrote a function that softens timerate transitions: you just specify the real time lapse and the condensed one and it does all the job. It avoids the unpleasant jumps and discontinuities associated with time speed changes. Unfortunately, we are talking of CELX here (although CEL can be easily embedded into CELX).
A link: http://www.shatters.net/forum/viewtopic.php?t=4970

Here is a thread where this kind of 'mission description' scripts are discussed in more specific terms:
http://www.shatters.net/forum/viewtopic.php?t=4543&highlight=

Keep your fine work!

Bye

Howdy dos,

dos wrote:... this one is 100% computer generated ... You just give it a link to a Web page and it builds a .cel script (no human editing/copy-pasteing required)

WOW!

That is amazing, especially for reading data from a web page and generating the script, with no human intervention.

Must be a long and tricky perl script!

One suggestion ... give longer text lines a little more time on the screen. Some of them go by pretty fast.

Way to go dos!

Keep 'em coming!

I like it , but I think the text needs some explanation, IMHO there are too many acronyms (OTM, PPR, PWS, SSI, ...). A link to a website where these are explained would be nice. Thanks for the script,

Harald

I apologize for not responding right away.

Toti:
Thanks for the quick reply!
I (ok, the perl script) did some careful event selection but
the goal was to give a complete overview of most (if not all)
of the Galileo mission events. This was not ment to be a
short and beautiful 'Jovian moons flyby script'. This is a
long and boring script for people who want to get a better
insight into the Galileo mission planning and learn answers
to questions like:

- When were exactly the pictures taken?
- What is the best time to execute a OTM (orbit trim manuver)?
- What instruments did they use from a far and what in close
encounters?
- What were the priorities?

As for the 'intelligent timerate manipulation', what I ment was
a better way to calculate the timerate between the events.
Right now you have to wait the same 5 seconds between to
events 1 minute and 1 day apart.

Don:

Thanks once again for your support!
The script is actually quite short (about 200 lines) and most
of it is the CEL code. Perl is unbeatable when it comes to data
parsing and processing.
As for your suggestion, the text is now displayed for 5 seconds
(used to be 4) nearer to the center, so it will, hopefully be
easyer to read.

Harry:
Ok, I added acronyms to the opening screen. Thanks for the
suggestion!

Anyway, the new and improved version is out! You will also
nead a slightly modified (a few corrections) Jupiter moon
locations file. You can download them from:

http://student.fizika.org/~dsvilko/celestia/gal.cel
http://student.fizika.org/~dsvilko/celestia/jupmoons.cel

Changes:
- text hopefully more readable
- better subject selection code
- real FOV of Solid State Imager (SSI)
- the script now tries to locate a matching tagret (location) in
moon locations file and position the camera acordingly
- blinking 'take-a-photo' frame marker

Tell me what you think.

DoS

dos wrote:The script is actually quite short (about 200 lines) and most
of it is the CEL code. Perl is unbeatable when it comes to data
parsing and processing.

That's amazing!

I just downloaded the new script, but the jupmoons link doesn't work. I'll go try it with the built-in location file...

Like the changes you made DoS, especially the "snapshot" feature Nicely done!

When I run this script, it really hits me as to how BUSY this probe was, for so many years. And makes me think about how BUSY Cassini is going to be, very soon now!

Thanks again, for a great script Mr. perl ... er I mean DoS.