Celestia Forums

Hi
I will like to use Celestia to build some nice animation for my PDA: i will use them while mastering a sci-fi RPG game (Dream Pod 9 "Jovian Chronicles", if you're interested).
The problem is that i can't do continous, seamlessy animation of a planet 'cause the "realism" of Celestia.

So i'm asking:

There's someone that will like to "build" for me two alternate solar systems?

One should have "fixed" planets (i mean: not orbiting around the sun) but rotating and with satellites orbiting with a "precise" time, so i can take a movie of, say, 28 Earth days and have a looping video (i think this may involve clouds movement also).

The second should have planet's orbits "tweaked" in the same way, so i can take a movie of the whole solar system having it looping endless.

It's a hard task to do? i'm asking too much?

Thanks in advance

EDIT:
I put "simple" in the title 'cause i don't need any 3d models/textures... i was just guessing about asking some "simple"

If someone make the work for you, fine, if not you will have to dig by yourself the forum to find the solution to your problem.

Just for info, since more than 1 year I'm here, you are the first user in asking people to work for you so quickly (5 posts)...

ElChristou wrote:If someone make the work for you, fine, if not you will have to dig by yourself the forum to find the solution to your problem.

You should have a place in some important position, this reply is soo many useful and intelligent, second only to the next sentence....

ElChristou wrote:Just for info, since more than 1 year I'm here, you are the first user in asking people to work for you so quickly (5 posts)...

... as said, this is the best answer i've found in a forum.
There's some kind of rule about how much post you should write before asking? or about how much years you should be in a group?
I'm tampering with celestia from years, i know my limits and my skills, i've just asked to diverse-skilled ppl if this is a thing someone can afford.

Pls take your marvelous mind for yourself. It's frustrating for poor minded ppl like me to see how God can be generous.

Hey relax, if you are using Celestia for years you should know there is no rules on the forum (apart a few ones you can find in users) and you should know that asking "just like this" for your own convenience (not for the community) is in general not very well seen...

Apparently after those years you are not aware of the rythm of the community, so just to enlight you, people in general are busy with their own stuffs, Dev are more than busy with the code, so as I was saying earlier, you should try it by yourself before asking, and if you really met problems that haven't been already solved (search the forum), then you are welcome to ask what's wrong.

If all this is too much to ask, sorry to say so, but regarding your autojudgment I'm pretty sure you will find out there some soft more adapted to your personnality... (indeed, Celestia require in general a high neuronal activity...)

Seems that we are out-tuned.
I'm using Celestia from years for the pleasure of using this app.
I was trying to build something in 2003 but i've discovered that Celestia needs a lot of knowledge to make thing works.
I'm a programmer, i feel better under C++ or VB than all things Celestia uses.
About asking for myself, there's:
a post asking for the same RPG game
a post asking for the (more or less) kind of need
some posts about placing planets, demonstrating an eclipse per month, and so on. None of these post (IF i'm right understanding, which is always a doubt) have not the final script/file/whatever to look at as sample.

There's ppl making galaxies (you too are one of them), i SUPPOSE that what i'm aksing is a simple thing, as much ppl SUPPOSES is simple to make a Visual Basic app that do something.

If is not simple, tell me why.
If it's simple, and you don't like to make it (which is perfectly understandable) then pls start explain to me what should i do or what should i understand.
Telling me "do it yourself if noone make that for you" is useful as a boat in a bottle.

parduz wrote:

ElChristou wrote:If someone make the work for you, fine, if not you will have to dig by yourself the forum to find the solution to your problem.

You should have a place in some important position, this reply is soo many useful and intelligent

The Big ElC important? Well, I don't think we actually have a formal rating system here. But I would throw in (my usual unsolicited two cents) that if one ranks importance by kindness, helpfulness, contributions and generally being in the role of peacemaker when conflicts DO arise... well, the Big ElC would qualify as one of the MOST important on the board.

But that's just me. As for you.....

Regarding building a solar system and capturing a movie.... What platform are you on? Not all platforms have a functional movie capture function. Also it really sounds like you are just trying to make a little animation movie. Perhaps someone else could weigh in on some simple animation software that would make the job easier? And, finally, it sounds like you might want to try tweaking around with the SSC files for the orbiting bodies in our solar system. You might be able to do it yourself pretty easily - though I'm still not totally clear on what you're asking. Hope that helps.

You are a programmer?
Then, no way, by analysing some solarsystem addons and scripts (available on the motherlode) you will find in a few minutes/hours all the keys to achieve your animation. Not very friendly with the settings in a ssc? just do some search on the forum to learn how they work...
Sorry, I cannot give you a ready to use solution, I'm not a ssc guru...

Hope someone else will give you some tips...

Bye.


PS:BTW, Celestia IS written in C++...

BlindedByTheLight wrote:...The Big ElC important? Well, I don't think we actually have a formal rating system here. But I would throw in (my usual unsolicited two cents) that if one ranks importance by kindness, helpfulness, contributions and generally being in the role of peacemaker when conflicts DO arise... well, the Big ElC would qualify as one of the MOST important on the board...

Steven, I do hope you are kidding...

BTW, it's a long time I haven't open your osX download page... is it actualized?

Are you aware DW has done a dds converter for osX? You could perhaps add a link like for the CmodTool...

BlindedByTheLight wrote:Regarding building a solar system and capturing a movie.... What platform are you on? Not all platforms have a functional movie capture function. Also it really sounds like you are just trying to make a little animation movie. Perhaps someone else could weigh in on some simple animation software that would make the job easier? And, finally, it sounds like you might want to try tweaking around with the SSC files for the orbiting bodies in our solar system. You might be able to do it yourself pretty easily - though I'm still not totally clear on what you're asking. Hope that helps.

Ok, so i try to explain better.
I use Celestia on WinXP, and capturing movie works well (at least as uncompressed avi). Then i reduce it at a size agreable by my PDA. The whole process works very good, so there's no need for clues about.
I then try to better explain what i'm asking.
Right now, i "GO" to the earth, i choose a good view, i speed up the time and i grab a movie of the earth/moon mini-system.

Then i open my video editor and i start searchig the right start/end frames do make a looping animation: there's no way to do that, 'cause the clouds, the moon, the shadows are never in the same position all toghether.

So i start thinking about how to do that. I, with my skills, can only thinks two solutions:
a) Building a whole solar system in a 3D designer and make my animations in this way. It's a lot of work, mostly tedious.
b) Keeping the great "flexibilty" and visual stunning of celestia and tampering with SSC files...or scripts?.... what's the best way? to archieve my goal.

So, what exactly i will like to have is (keepeing the Earth as example):
A Fake Solar system with a Earth fixed in its position (not orbiting around the sun).
Then i will like to alter the moon orbit, the clouds movement and so on so i can have the same image each (say) 28 days. So i can capture a 30 days lenght movie and find the identical frames to make a looping movie.

If lookin at the Earth seems (SEEMS) simple, i'm wondering what kind of orbits the Jovian moons needs to achieve the same result: they're so much, so i need to compute each orbit to have, every N jovian days, the same, exactly "image".

My difficults starts from the beginning (i still don't know the best method to do that) and ends with the hardest part: cumpute orbits, vectors and so on.
It's not my bread, and it's not something i'm able to do right now.
My knowledge is so little that i can't ever understand if this is something celestia can do, and what grade of difficulty have this "goal".

Thanks for your attention

ElChristou wrote:

BlindedByTheLight wrote:...The Big ElC important? Well, I don't think we actually have a formal rating system here. But I would throw in (my usual unsolicited two cents) that if one ranks importance by kindness, helpfulness, contributions and generally being in the role of peacemaker when conflicts DO arise... well, the Big ElC would qualify as one of the MOST important on the board...

Steven, I do hope you are kidding...

I guess we could add modesty to the list! As for my page, I have been so slammed at work I haven't had even REMOTELY the time to update it. But I still plan to.

I will try to update the link for the tool. Problem is, my web-software doesn't yet work on Intel Macs so I'm a little behind. Also the time.

Cheers!

Ah... I see. Basically you want the final frame of your loop to match up perfectly with the start frame - which, in our solar system, just doesn't happen very often.

Well, again, my two cents would be to make a copy of the solarsys.ssc file (and save the original). Then play around with the orbital numbers until you get something that works the way you want it (also you can just turn off cloud rotation). Unless I'm missing something, it doesn't seem like it will take too much tweaking to find the right mix. Like ElC, I'm not an SSC guru but it seems like that is your best bet.

You might want to try asking that specific question in a new thread maybe titled "Orbital Parameter SSC Question" then ask - "What do I need to change my earth and moon SSC orbital parameters (rotation and revolution) to in order to get all the bodies in the exact same position 28 days later?"

Steven, if you are too busy we should think in something to keep the page updated... no way I can help?

parduz wrote:So, what exactly i will like to have is (keepeing the Earth as example):
A Fake Solar system with a Earth fixed in its position (not orbiting around the sun).

You don't need to do this.
Follow Earth, select the sun (H or 0 zero), press : (Colon) to lock the phase. Now the sun stays in the same position relative to the Earth.

If you do want to slow the Earth down (I don't recommend this because the Earth will fall into the sun and everybody will burn to a crisp), then increasing the orbital period is what you need to do. Just pick a large number.

parduz wrote:Then i will like to alter the moon orbit, the clouds movement and so on so i can have the same image each (say) 28 days. So i can capture a 30 days lenght movie and find the identical frames to make a looping movie.

If the cloud speed was an exact fraction of the moon's orbit this can work. You could also make the clouds stand still.

parduz wrote:If lookin at the Earth seems (SEEMS) simple, i'm wondering what kind of orbits the Jovian moons needs to achieve the same result: they're so much, so i need to compute each orbit to have, every N jovian days, the same, exactly "image".

Conveniently, the inner three Galilean moons are roughly in a 1:2:4 resonance so it's easy to make a repeating loop with them. Just tweak the orbits so they are exactly 1:2:4 and you'll be able to loop with them. Callisto is harder because it's not in a resonance with the others. Its period is 9.43 times that of Io. You could tweak this so it was 9.5 times Io, then you could make a fairly accurate movie that would repeat after two orbita of Callisto.

parduz wrote:My difficults starts from the beginning (i still don't know the best method to do that) and ends with the hardest part: cumpute orbits, vectors and so on.
It's not my bread, and it's not something i'm able to do right now.
My knowledge is so little that i can't ever understand if this is something celestia can do, and what grade of difficulty have this "goal".

Thanks for your attention

Some documentation that may be helpful:
http://www.celestiamotherlode.net/creat ... CGuide.zip

ElChristou wrote:Are you aware DW has done a dds converter for osX? You could perhaps add a link like for the CmodTool...

Sorry for being off topic here, but the DDS tool is still at the experimental stage. It needs to be updated to reflect recent changes to the DDS library that it's using, the user interface needs to be tweaked, and of course there's your (ElChristou) icon. I'll post on the forum when I'm satisfied with releasing it for general use.

parduz:

Here is a little thick that may make this simpler than you think. You can cheat the differance at the end of the clip by dissolving to the begining of the clip over a period of time. Don't know what software you are using but most have what is called cross dissolve or something like it. Make the dissolve last about 10-15 seconds. Do this for the clouds only not the land and oceans areas I would try to line them up at the first and last frame. You will notice if you are looking for it but most will not see it. I don't think you need to record 28 or 30 days unless you want the moon moving in the viewing for a complete cycle.

Hope this helps without having to build the whole universe.

Don

dirkpitt wrote:

ElChristou wrote:Are you aware DW has done a dds converter for osX? You could perhaps add a link like for the CmodTool...

Sorry for being off topic here, but the DDS tool is still at the experimental stage. It needs to be updated to reflect recent changes to the DDS library that it's using, the user interface needs to be tweaked, and of course there's your (ElChristou) icon. I'll post on the forum when I'm satisfied with releasing it for general use.

if we link the actual state it can be tested by more people and you will get more feedback; this way as you are also very busy you don't have to hurry for another release... no?