Boing 747 flying - now what?

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Topic author
Niels

Boing 747 flying - now what?

Post #1by Niels » 15.10.2002, 04:19

Hi,

I have below. How do I rotate the 3DS so it is placed right with wings to the side and looks as if it flies across the Earth?
How to I locate it anywhere at startup?

Download 747.3ds model here:
http://www.3dcafe.com/models/747.zip

"Boing 747" "Sol/Earth"
{
Class "spacecraft"
Mesh "747.3ds"
Radius 0.015 # is about 30 meters long

EllipticalOrbit {
Period 0.15
SemiMajorAxis 6388
AscendingNode 10
# from Earth's radius

Eccentricity 0.0
Inclination 0.0
}

RotationOffset 260

Albedo 0.0

}

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selden
Developer
Posts: 10192
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Location: NY, USA

Post #2by selden » 15.10.2002, 11:43

Niels,

The "MeanAnomaly" is the position in degrees along the (equivalent circular) orbit path with respect to the "PeriCenter". By definition, the mean anomaly is 0 at the "Epoch", which is the Julian Date of pericenter passage in Celestia.

You can specify that position using either MeanAnomaly or MeanLongitude. You can specify the pericenter by using either ArgOfPericenter or LongOfPericenter. I suspect using the longitude will be easier in this case.

The following terms can be used to specify the object's orientation:
RotationPeriod (hours) [#]
If not supplied, Rotation period = orbital period
RotationOffset (deg)
RotationEpoch (JulianDay)
Obliquity (deg)
LongOfRotationAxis (deg)
PrecessionRate (deg)

I hope this helps.
Selden

Topic author
Niels

Boing

Post #3by Niels » 15.10.2002, 12:45

Hi,

I'm sorry to say it; no.
I have tried different things but I try without knowing nothing about these parameters.

I'm sure the params are just great I just dont know how to use them.

Rassilon
Posts: 1887
Joined: 29.01.2002
With us: 22 years 9 months
Location: Altair

Post #4by Rassilon » 15.10.2002, 16:39

Yeah neither did I when I first started...I would just use just what you need to place it...Obliquity RortationPeriod SemiMajorAxis Period....that should do...then work your way up....
I'm trying to teach the cavemen how to play scrabble, its uphill work. The only word they know is Uhh and they dont know how to spell it!


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