How to make add-ons?
How to make add-ons?
How do you make add-ons such as planets and suns? And please can someone give me a simple answer because I am only 14 and I don't really understand all the computer phrases
I have a Mac too, so it isn't a problem. Just open the SSC files with TextEdit (SSC files are just plain Text files). Open the textures (JPG and PNG) with a program like Photoshop (or something similar). That's all there is, for the moment.
Good luck.
Good luck.
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"
I have created a few fictional solar systems, and here is how I do it.
You will find the following helpful:
* Spreadsheet software
* Image editing software
* Text editor
* Basic knowledge of Keplerian orbits and Newtonian gravity
Orbits:
* I maintain a spreadsheet that computes the orbits of the planets and moons. For the planets, I can enter in the mass of the star in solar masses, and then for each planet I add in the distances I want to use for that planet. The spreadsheet then calculates the periods of the orbit.
* For moons, I use a different spreadsheet that produces output in a format that can be pasted straight into an SSC file.
Textures:
* To create planet textures, good image editing software is essential. You will also find it useful to download images that you can manipulate, such as hi-res textures for Jupiter and Saturn, and Blue Marble. Bland textures for planets like Neptune can be created from scratch as needed.
Now you may not understand all this, but that's okay. You can learn a lot by downloading a good addon and inspecting it in detail. You may also find the SSC users' guide helpful - it's in the Documentation section on the Motherlode.
You will find the following helpful:
* Spreadsheet software
* Image editing software
* Text editor
* Basic knowledge of Keplerian orbits and Newtonian gravity
Orbits:
* I maintain a spreadsheet that computes the orbits of the planets and moons. For the planets, I can enter in the mass of the star in solar masses, and then for each planet I add in the distances I want to use for that planet. The spreadsheet then calculates the periods of the orbit.
* For moons, I use a different spreadsheet that produces output in a format that can be pasted straight into an SSC file.
Textures:
* To create planet textures, good image editing software is essential. You will also find it useful to download images that you can manipulate, such as hi-res textures for Jupiter and Saturn, and Blue Marble. Bland textures for planets like Neptune can be created from scratch as needed.
Now you may not understand all this, but that's okay. You can learn a lot by downloading a good addon and inspecting it in detail. You may also find the SSC users' guide helpful - it's in the Documentation section on the Motherlode.
If you haven't already, I'd suggest taking a look at
http://www.lepp.cornell.edu/~seb/celest ... intro.html
Many of the details mentioned above are irrelevant when starting to learn how to create an Addon. You can make planets orbit a star very easily, although the details of their orbits are likely to be unrealistic.
http://www.lepp.cornell.edu/~seb/celest ... intro.html
Many of the details mentioned above are irrelevant when starting to learn how to create an Addon. You can make planets orbit a star very easily, although the details of their orbits are likely to be unrealistic.
Selden
Ok thank you, just a general query do you know what I would have to change
CustomOrbit "vsop87-venus"
EllipticalOrbit {
Period 0.6152
SemiMajorAxis 0.7233
Eccentricity 0.0068
Inclination 3.3947
AscendingNode 76.681
LongOfPericenter 131.533
MeanLongitude 181.979
}
RotationPeriod 5832.479839
Obliquity 178.78
EquatorAscendingNode 300.22
RotationOffset 137.45
Albedo 0.81
to to make it like the moons orbit and so on?
CustomOrbit "vsop87-venus"
EllipticalOrbit {
Period 0.6152
SemiMajorAxis 0.7233
Eccentricity 0.0068
Inclination 3.3947
AscendingNode 76.681
LongOfPericenter 131.533
MeanLongitude 181.979
}
RotationPeriod 5832.479839
Obliquity 178.78
EquatorAscendingNode 300.22
RotationOffset 137.45
Albedo 0.81
to to make it like the moons orbit and so on?
I'm sorry: I don't know what you mean by "to make it like the moons orbit and so on?"
Do you mean that you want Venus to orbit around the Earth?
In that case, you could make a copy of the Moon's definition and make appropriate changes to it. (or not: just replace the Moon entirely).
1&2 below are the only changes that are absolutely necessary. Of course, this isn't very realistic until after step #7.
1) change the Texture declaration to specify Venus' surface texture instead of the Moon's.
2) change its Radius to be the same as Venus
3) delete the "custom orbit" line so it doesn't follow the actual Moon's orbit.
4) copy Venus' Atmosphere declaration
5) change the SemiMajorAxis so its orbit is substantially different.
6) modify other details if you want.
7) learn celestial mechanics so you understand how to make the Earth and moonVenus appropriately orbit around their common barycenter.
Do you mean that you want Venus to orbit around the Earth?
In that case, you could make a copy of the Moon's definition and make appropriate changes to it. (or not: just replace the Moon entirely).
1&2 below are the only changes that are absolutely necessary. Of course, this isn't very realistic until after step #7.
1) change the Texture declaration to specify Venus' surface texture instead of the Moon's.
2) change its Radius to be the same as Venus
3) delete the "custom orbit" line so it doesn't follow the actual Moon's orbit.
4) copy Venus' Atmosphere declaration
5) change the SemiMajorAxis so its orbit is substantially different.
6) modify other details if you want.
7) learn celestial mechanics so you understand how to make the Earth and moonVenus appropriately orbit around their common barycenter.
Last edited by selden on 11.02.2008, 19:18, edited 1 time in total.
Selden
Then do follow my instructions above: you want to terraform the Moon, not Venus.
Step 1 is all you really need to do to terraform the Moon: provide a new Texture image to make its surface look different.
The very simplest way to do this is to copy your map of the terraformed surface into Celestia's folder textures/medres/ and give it the name moon.jpg
Then you could copy the Earth's atmosphere declaration to give it clouds and haze.
Step 1 is all you really need to do to terraform the Moon: provide a new Texture image to make its surface look different.
The very simplest way to do this is to copy your map of the terraformed surface into Celestia's folder textures/medres/ and give it the name moon.jpg
Then you could copy the Earth's atmosphere declaration to give it clouds and haze.
Selden
Here's another way to accomplish the same thing.
Create this file as terraformed_moon.ssc in your extras folder
[data]
Modify "Moon" "Sol/Earth" {
Texture "terraformed_moon.*"
Atmosphere {
Height 60
Lower [ 0.43 0.52 0.65 ]
Upper [ 0.26 0.47 0.84 ]
Sky [ 0.40 0.6 1.0 ]
Sunset [ 1.0 0.6 0.2 ]
CloudHeight 7
CloudSpeed 65
CloudMap "earth-clouds.*"
}
}
[/data]
and put your new surface texture (named terraformed_moon.jpg) into Celestia's /textures/medres folder, although that's not the best place for it.
Please do read the web page mentioned above so you understand where appropriate files should be put.
Create this file as terraformed_moon.ssc in your extras folder
[data]
Modify "Moon" "Sol/Earth" {
Texture "terraformed_moon.*"
Atmosphere {
Height 60
Lower [ 0.43 0.52 0.65 ]
Upper [ 0.26 0.47 0.84 ]
Sky [ 0.40 0.6 1.0 ]
Sunset [ 1.0 0.6 0.2 ]
CloudHeight 7
CloudSpeed 65
CloudMap "earth-clouds.*"
}
}
[/data]
and put your new surface texture (named terraformed_moon.jpg) into Celestia's /textures/medres folder, although that's not the best place for it.
Please do read the web page mentioned above so you understand where appropriate files should be put.
Selden