orbits help!!!!!!

General discussion about Celestia that doesn't fit into other forums.
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guest

orbits help!!!!!!

Post #1by guest » 18.06.2003, 00:52

What do the orbits mean. The blue lines are not complete
Why? Also there looks to be a triangle in the circle. What
does that represent? Is it apogee, and perigee? The user guide does not say. If anyone knows, help

:?

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selden
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Post #2by selden » 18.06.2003, 01:16

I'm not sure what you mean by "the blue lines are not complete". They are on my system, but...

Celestia only calculates 10 points around each closed orbit and essentially draws straignt lines between them. This is to minimize the amount of calculation that needs to be done between frames. More calculations = slower frame rates. If the orbiting body is not close to one of those 10 points, it can be quite a distance away from where Celestia draws the closest line. The position where the orbiting body is drawn is quite accurate, but the lines aren't. (I guess I should add this to the FAQ.)

I'm also not sure what you mean by a "red triangle in the circle". Do you mean the red Marker? That's usually a diamond, though, which indicates what object is Selected. Se the Users' FAQ at the top of this forum, Q&A #11 explain how to turn it off and on. (Control-K)

If typing a Control-K a few times doesn't turn off and on the red thing you're seeing, you'll have to provide a picture with circles and arrows and a paragraph on the back explaining ... Oh, sorry.... I got a little carried away :)

Does this help?
Selden

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Post #3by billybob884 » 18.06.2003, 03:03

i thought it was 100 points?
Mike M.

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selden
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Post #4by selden » 18.06.2003, 03:14

Mike,

You're right: Chris wrote "100 plus" in his response to a question about a quirk in the orbit of Callisto. I dunno how I got 10 out of that!

I gotta go quick change a faq entry...

Added later:
Chris wrote "100 plus" when commenting about xyz trajectories.
In another thread he said about keplerian orbits "if i calculate 100 points..."
I haven't actually looked at the code for it, so I dunno how many actually are being calculated, so I cheated and put "100 or so" in the faq. Oh, well.
Selden

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guest

Post #5by guest » 18.06.2003, 16:50

I never said red triangle. Red is only when the orbit is selected.
The orbit is not complete and looking form the
top zooming out there are lines that connect looking like a triangle

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Post #6by JackHiggins » 18.06.2003, 18:18

Guest wrote:I never said red triangle. Red is only when the orbit is selected.
The orbit is not complete and looking form the
top zooming out there are lines that connect looking like a triangle


Are you using an xyz like galileo/voyager/cassini etc? Or does it happen to every orbit?
- Jack Higgins
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Topic author
guest

Post #7by guest » 19.06.2003, 00:48

I am talking about the planets orbits. Look down from the top or bottom of a planet. Zoom out press o for orbits. You will see
blue orbits of the planet or moon, but there are two spaces
in them. This happens for every planet and moon. From the space
in the orbit a straight line connects that looks like a triangle. What is that there for? Why are the spaces there? I hope I explained it correctly. I am having problems pasting the image :oops:

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Post #8by selden » 19.06.2003, 01:13

I'm afraid the reason we're having problems understanding what you're trying to describe is that we don't see anything like that.

Here's a snapshot taken by Celestia on my home system looking directly down on Saturn. I don't recognize anything that could be described by what you're saying. All the orbits are perfectly round, no triangles are visible, and there aren't any gaps, either.

Image
(as usual, this links to a larger image)

and here's a Cel:// URL for this viewpoint:

cel://Follow/Sol:Saturn/2003-06-19T00:16:29.03169?x=ID1GFyE4fbW3DA&y=CgjyewYReB/+/////////w&z=VdlsY27+Q09x/////////w&ow=0.521702&ox=0.722879&oy=0.357468&oz=0.278370&select=Sol:Saturn&fov=43.293781&ts=1.000000&rf=1029182210&lm=1862270976<d=0&rf=71603&lm=20

(You can't paste images directly into posts to the forum. You have to upload them to a Web server somewhere and provide a URL pointing to them.)

I fear you're going to have to provide a detailed description of your system and the software you're running. It's starting to sound like it might be a hardware problem of some kind -- memory, fpu or graphics.

My system:
256MB ECC memory, 500MHz P3 (dual processor), WinXP Pro SP1
128MB Nvidia GeForce4 Ti 4200, Detonator 43.45, OpenGL 1.4.0
Celestia v1.3.1pre4
Selden

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Post #9by billybob884 » 19.06.2003, 02:54

selden wrote:(as usual, this links to a larger image)


heh, you've posted so many images, i really don't think you need to put that anymore
Mike M.



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selden
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Post #10by selden » 19.06.2003, 02:58

But I don't know if this particular anonymous guest has noticed that, what with the orbital problems he/she is frustrating over.

And what would you do if someday it linked to a smaller image? ;)
Selden

Topic author
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Post #11by guest » 19.06.2003, 15:57

Hey selden, that image you showed was exactly what i was trying
to describe. The problem is on my celestia the circles are not complete
there have two gaps per orbit and from the gaps are two striaght lines
connecting from one gap to another area that is without a gap. This happened in 1.30 and 1.31 I am having trouble pasting the image
If can can tell me exactly how to paste an image that would help.
I have pasted images before but not here so maybe I am missing something. But at least we are talking about the same thing. :oops: :oops:

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Post #12by selden » 19.06.2003, 17:11

Guest guest,

As I said, you have to put the image on a Web server somewhere and then put the URL of that Web server into your messaage here. Please read the phpBB forum software FAQ. It's on a button at the very top of this page.

It really sounds to me now like you have a buggy OpenGL driver. It's not drawing all the lines. Please read the "Preliminary User's FAQ" which is at the beginning of the Users Forum. Follow the instructions in Q1/A1 and Q2/A2.
Selden

Guest

Post #13by Guest » 20.06.2003, 16:33

I read the FAQ but Idon't know where to put the image.
Anyway it does not really matter. You tol;d me what i needed
to know. It's not supposed to happen. It's either a buggy driver
asyou say or my primitve graphics card. I am shopping for a new
one. Thanks again


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