Celestia Forums

I was checking the Selden's page "Celestia Notes", and exactly the paragraph "Script Commands", that I find very clear and upgraded with respect to the one in Celestia Home page.
I have only some doubts about the following new commands:
(sorry, all the round braces must be considered as square braces)
1- in the GOTO vector, I know that the ( 0 1 0 ) is for equatorial position, the ( 1 0 0 ) is for polar position, but what is the ( 0 0 1 ) result?
2- what is the effect in GOTOLOC of the commands xrot - yrot - zrot?
3- the PRELOADTEX makes what I'm supposing, i.e. the texture preloading? If yes, this means that instead of waiting many seconds for big texture loading, this can be done previously, or while performing other commands? This should be very nice.
4- the LOOKBACK command is what appears, i.e. moves the vision target of 180 deg?
5- the ROTATE axis vectors are the same ones of the SETORIENTATION command? I.e., just for an example, ( 90 1 0 0 ) means the same "rotate 90 deg transversally along X axis"?
6- I tried to give the command SETFAINTESTAUTOMAG85DEG, but the answer was "this command doesn't exist". Is it part of a future improvement, perhaps in Celestia 1.2.6?
7- for SETPOSITION command, what are doing the base and offset vectors, and how are these? Like GOTO or like SETORIENTATION, or something else?
8- what is the effect of the LOCK command?
9- and of the CHASE command?
As someone knows I'm trying to prepare astronomy teaching .cel files for our Astronomy Museum Lectures for the students, so the understanding of these commands is very important for us.
Many many thanks to whom will be so kind to solve my doubts.

Andrea
157 Frasso Sabino Observatory

ANDREA wrote:I was checking the Selden's page "Celestia Notes", and exactly the paragraph "Script Commands", that I find very clear and upgraded with respect to the one in Celestia Home page.
I have only some doubts about the following new commands:
(sorry, all the round braces must be considered as square braces)
1- in the GOTO vector, I know that the ( 0 1 0 ) is for equatorial position, the ( 1 0 0 ) is for polar position, but what is the ( 0 0 1 ) result?
2- what is the effect in GOTOLOC of the commands xrot - yrot - zrot?
3- the PRELOADTEX makes what I'm supposing, i.e. the texture preloading? If yes, this means that instead of waiting many seconds for big texture loading, this can be done previously, or while performing other commands? This should be very nice.
4- the LOOKBACK command is what appears, i.e. moves the vision target of 180 deg?
5- the ROTATE axis vectors are the same ones of the SETORIENTATION command? I.e., just for an example, ( 90 1 0 0 ) means the same "rotate 90 deg transversally along X axis"?
6- I tried to give the command SETFAINTESTAUTOMAG85DEG, but the answer was "this command doesn't exist". Is it part of a future improvement, perhaps in Celestia 1.2.6?
7- for SETPOSITION command, what are doing the base and offset vectors, and how are these? Like GOTO or like SETORIENTATION, or something else?
8- what is the effect of the LOCK command?
9- and of the CHASE command?
As someone knows I'm trying to prepare astronomy teaching .cel files for our Astronomy Museum Lectures for the students, so the understanding of these commands is very important for us.
Many many thanks to whom will be so kind to solve my doubts.

Andrea
157 Frasso Sabino Observatory

Some time ago, I posted a lengthy script that uses many newer commands, but few seem to have noticed it...
http://www.celestiaproject.net/forum/viewtopic ... hlight=pan

The different actions are even commented. However, in the posted version, I have left out my new 'lookback' command that as you said does exactly what the name says...

Bye Fridger

t00fri wrote:Some time ago, I posted a lengthy script that uses many newer commands, but few seem to have noticed it...
http://www.celestiaproject.net/forum/viewtopic ... hlight=pan

The different actions are even commented. However, in the posted version, I have left out my new 'lookback' command that as you said does exactly what the name says...

Bye Fridger

I noticed it, sadly it didnt work, it was very lengthy and I did not have the skills, then, to trouble-shoot it ! ( I did not see any #comments in it either ? }
Later I discovered that it needed "pan" ( whatever that is) to be installed ( not in the celestia distribution?) and no info in the script.
A script pertaining to something existing in the celestia distribution would nodoubt be more helpful to neophytes and beginners !?

For an expert these sorts of things are no doubt trivial, but then, an expert has no need of a guide ??
It has always semed a shame to me that something as wonderful and interesting and delightful as Celestia, with all the work that has been put into it by expert programers should fall down on the matter of a helpful guide to lesser mortals in the using thereof ! if you see what I mean ?

For example, why put in a "lookback" code and then not document it in the scripts commands document on the Celestia web site ? (for just one example) It was a long time (days if not weeks?) before someone mentioned this one in passing ( Selden was it ?) before it came to prominence,,,

For another example, for a long time now Selden has included, on his very helpful website a trawl through the script commands found in the source codes, but the (arguments? parameters? wot is the right term?) to many of those commands still remain unexplained/undefined by whomsoever wrote them in,,,, why so?,, would it not be helpful for someone(whomever did it) to document same?

Corncrake wrote:I noticed it, sadly it didnt work, it was very lengthy and I did not have the skills, then, to trouble-shoot it ! ( I did not see any #comments in it either ? }

It requires Celestia 1.2.5 and then I assure you, it runs out of the box. The comments I am referring to are comments that are displayed on the screen(!) while the script is working...

Later I discovered that it needed "pan" ( whatever that is)
to be installed ( not in the celestia distribution?) and no info in the script.

Apparently, you did not care to read the introduction to my script:

t00fri wrote:Here is a script that I wrote a little while ago. It's about Pan, a little moon of Saturn orbiting in the Encke division...

The moon Pan is part of the standard Celestia 1.2.5 distribution!

In extras: grep Pan * gives:
minormoons.ssc:"Pan" "Sol/Saturn",

i.e. it is defined in the standard file minormoons.ssc.

A script pertaining to something existing in the celestia distribution would nodoubt be more helpful to neophytes and beginners !?

Also Newbies can be expected to spend /a little time/ reading...;-). Notably in case of a rapidly developing package like Celestia, it is also understood that one has to upgrade to the actual version regularly.

For an expert these sorts of things are no doubt trivial, but then, an expert has no need of a guide ??
It has always semed a shame to me that something as wonderful and interesting and delightful as Celestia, with all the work that has been put into it by expert programers should fall down on the matter of a helpful guide to lesser mortals in the using thereof ! if you see what I mean ?

If the developers would spend their little available spare time to writing guides at this point, who should do the development??

People like yourself are cordially invited to help out here! Get together with Frank (fsgregs), for example, who started off as a Newbie, spent much time learning the use of Celestia from the point of view of a non-expert and is now preparing a most valuable guide document...

Clearly, this attitude is "slightly" more time consuming that writing half a page of critics, before even carefully studying what is available...

For example, why put in a "lookback" code and then not document it in the scripts commands document on the Celestia web site ? (for just one example) It was a long time (days if not weeks?) before someone mentioned this one in passing ( Selden was it ?) before it came to prominence,,,

The lookback key shortcut is explained in the file controls.txt of the distribution and listed in the ChangeLog file, as is standard in OpenSource programming. The ChangeLog file can also be clicked from the shatters.net site, I believe. All changes in the code are at least mentioned there.

While I am the author of the 'lookback' command in Celestia, I have no write-access to the WEB document you are referring to. This is an early outdated attempt by Chris, but /not part/ of the Celestia package. As I pointed out, we are all very busy people and it appears more sensible to use our little available time for introducing new features into Celestia instead of writing guides about the old ones;-).

If you would care to register in the forum and attentively and regularly follow what is going on here, the chances are very high that you will learn very easily and fast, how to use any new features that have been implemented in the code...


Bye Fridger

>Me>I noticed it, sadly it didnt work,
t00fri>It requires Celestia 1.2.5 and then I assure you, it runs out of the box.

Hmmm, that is odd, I have 1.2.5 and it didnt ! ( see below ** )

The comments I am referring to are comments that are displayed on the screen(!)

Ah! That is why I didnt see them then

The moon Pan is part of the standard Celestia 1.2.5 distribution!
In extras: grep Pan * gives:
minormoons.ssc:"Pan" "Sol/Saturn",

Not in the one I have, it would seem! I am downloading it again to try to find out what has happened.
I see you ref to grep, so could it be that it is in the Linux version and not the Windows ?? Just a guess, it will take a little time for my download to complete ( 11M on a 56k modem)

( Oh, I forgot, it is an exe not a zip, hmm how am I going to look into that for Pan without overwriting my present celestia set up,, ignore that, just talking to myself ! I'll go offline and think about this )

Update :
I now have two installations of 1.2.5 !
no Pan, no minormoons, in the newly downloaded and installed version
(nothing in the extras folder at all )

corncrake wrote:Update :
I now have two installations of 1.2.5 !
no Pan, no minormoons, in the newly downloaded and installed version
(nothing in the extras folder at all )

It seems, unfortunately, that you are right in the sense that the /binary/ Windows distribution comes with an empty extras folder! However the official source code distribution does have all these files in and so do the /binary/ and /source/ Linux distributions that Christophe and I prepared. Chris did the packaging of the Windows stuff. So he might either have forgotten of including the extras files or decided it was too much in whatever sense;-).

I rarely use the Windows distribution, at best for checking things out...

If I am not wrong, you did not specify above what operating system you are using...

What I do not understand why you did not have a look on the main Celestia site at shatters.net that offers the minor moons in well documented form as the first add-on together with an installing instruction!? What else do you want? Just there to read and use...

You can also click there the Revision Log that informs about the actual code changes. You will also find there

lookback{}

which is all that is needed;-): No arguments as you can see "{}" and doing exactly what its name says: "Look Back"....


Bye Fridger

t00fri wrote:If I am not wrong, you did not specify above what operating system you are using...

If I am not wrong, I dont believe you specified that your script was limited in its operating systems ?
Thus I did not think it necessary and did not wish to make my post overly long

anyway :
you said "Some time ago, I posted a lengthy script that uses many newer commands, but few seem to have noticed it"

I thought that you might therefore be interested to know that someone did notice it ! And, although I ought to have known better, I forlornly hoped that you might be interested to know that this user ( and by inference possibly others ) could not run it and might be interested in sorting out why not, in an effort to make your script more widly interesting to others !
You may be surprised to know that I am (was) on your side in the fact that you programers (-you programers- in the general sense, not you in particular Fridger ) have lots to spend your time on. I was sugesting ( again forlornly it seems) a method (documentation or at least hints to the wise ) how a greater audience could be induced to appreciate your great efforts the more so.

lookback{}
which is all that is needed;-):
No arguments as you can see "{}"

If I am not wrong, I dont believe I said that it should have ?
My ref to arguments was in another paragraph in which I was talking about many other script commands that I found in Selden's magnum opus.
It seems that i am not the only one that needs to do some reading and concentrating Fridger ??

This has become tiresome, I am sorry I rattled your ivory tower,
I hope you and Linux have a good time together, byebye.

corncrake wrote:If I am not wrong, I dont believe you specified that your script was limited in its operating systems ?

My script is indeed not limited to a particular OS! It just so happens that Chris packaged the minormoons stuff /separately/ on his site, while it is included /both/ in the Windows/Linux source and Linux binary distributions.

lookback{}
which is all that is needed;-):
No arguments as you can see "{}" If I am not wrong, I dont believe I said that it should have ?

I am aware that you did not mention arguments, but usually this is where more detailed info is required. In case of no arguments like lookback, and given such a mnemnonical name, you can do nothing wrong by trying it out and looking what it does;-)...

I am sorry I rattled your ivory tower, I hope you and Linux have a good time together, byebye.

Most of what I am coding in Celestia is actually not specific to Linux. Only Chris does the packaging for Windows while others do the Linux packaging. He never told the rest of us that he left things out for the /binary/ Windows package that are in the official Celestia /source/ archive...

Sorry.

Bye Fridger