Assorted questions, mostly about models/textures and orbits

[straight]

Is there a option for alternate textures with stars? Or is there a way to get the star textures to change resolution when you change resolution with r/R? (I have a nice pretty gstar texture, but it's too big for everyday use--I get a hiccup every time the Sun comes into view).

Does anyone have a working link to the Stonehenge model?

How do I get something to orbit in the opposite direction?

Has anyone figured out how to write a script so that you go to a moon/satellite then orbit it until the planet is centered in view behind it?

How can I make a spacecraft orbit so that it is always facing in the direction it is moving (for instance, I'd like to put some Tie Fighters in orbit around a Star Destroyer and make it look like they're flying rather than tumbling). Anyone have a reference that would explain how the Orientation and RotationOffset commands work?

Is it possible to change which textures a model uses? Some models come with textures and some don't, is it possible to add textures to a model?

Some of the spacecraft models I have don't use the textures they came with, they're just plain, blinding white. Even when I've re-sized the textures to fit my video card. Sometimes a model that used to have textures suddenly doesn't. Any idea what could be causing that?

Does changing the size of an object change how it uses textures? When I scaled the Millenium Falcon down to actual size from the default it came with, some of the textures disappeared, I think.

[selden]

Is there a option for alternate textures with stars? Or is there a way to get the star textures to change resolution when you change resolution with r/R? (I have a nice pretty gstar texture, but it's too big for everyday use--I get a hiccup every time the Sun comes into view).

not yet

Does anyone have a working link to the Stonehenge model?

it seems to have evaporated from GeoCities. Hopefully Jestr will find a home for it soon.

How do I get something to orbit in the opposite direction?

add 180 degrees to the inclination

Has anyone figured out how to write a script so that you go to a moon/satellite then orbit it until the planet is centered in view behind it?

invoke the same routine that the command "C" uses I dunno if it's been implemented yet. Hopefully DonG. knows

How can I make a spacecraft orbit so that it is always facing in the direction it is moving (for instance, I'd like to put some Tie Fighters in orbit around a Star Destroyer and make it look like they're flying rather than tumbling). Anyone have a reference that would explain how the Orientation and RotationOffset commands work?

For a circular orbit, you can just set its RotationPeriod to be its orbital Period/24. I think Grant Hutchison wrote about the object orientation directives in a posting some time ago. Use the forum Search page.

Is it possible to change which textures a model uses? Some models come with textures and some don't, is it possible to add textures to a model?

You have to edit the 3DS model file, either directly with a binary editor or Emacs (to change the names of textures that already are defined), or with a 3D modelling program (to apply new textures to different parts of the model). Many people here use Anim8or.

Some of the spacecraft models I have don't use the textures they came with, they're just plain, blinding white. Even when I've re-sized the textures to fit my video card. Sometimes a model that used to have textures suddenly doesn't. Any idea what could be causing that?

There are lots of possible causes. See http://www.lns.cornell.edu/~seb/celestia/addon-intro.html#6 for some of them.

Does changing the size of an object change how it uses textures?

no

When I scaled the Millenium Falcon down to actual size from the default it came with, some of the textures disappeared, I think.

It could be that it wasn't displaying textures properly to begin with (see above). Changing its scale might have caused you to look at it from a different direction so it picket up a different surface texture image file.

[Cham]

To make an object rotate in the reverse sense, you could just put a sign in front of the RotationPeriod number. Easy.

[Guest]

Thank you for the help! Selden, your Celestia webpages are fantastic and have already helped me quite a bit. Somehow I'd skipped over your intro to add-ons. Thanks for sharing all that info with everyone.

Here is the URL for the thread about Object Orientation, in case anyone else is interested (boy, did I guess wrong about what the four numbers did, no wonder I couldn't figure it out--clearly my cerebellum did not evolve in free fall).

I hope the Implementors add a command that will orbit the currently followed object until centered on some other object. That would be cool.

Is there a "command line" function that lets you type scripting commands in and have Celestia execute them immediately?

[don]

Selden, thanks for your vote of confidence, but I'm not very good at scripting orbital stuff yet. I'm sure there are some who are though, like DoS -- if he is looking here. Or maybe folks could look at one or more of DoS's scripts in the Scripting forum, and figure it out that way.

Is there a "command line" function that lets you type scripting commands in and have Celestia execute them immediately?

Yes, Harald Schmidt wrote a script called "luaconsole". The topic for it is here: http://shatters.net/forum/viewtopic.php?t=4280. This script allows you to enter Celx commands (not Cel) and have them executed immediately.

[Harry]

Has anyone figured out how to write a script so that you go to a moon/satellite then orbit it until the planet is centered in view behind it?

invoke the same routine that the command "C" uses I dunno if it's been implemented yet. Hopefully DonG. knows

Chris implemented this in CELX as:

Code: Select all

observer:centerorbit(object target [, number duration])

It's in CVS since mid february, so any 1.3.2pre since then should have it.

Unfortunately my docs aren't up to date (and as a result Don's aren't too)... I guess I have to update them Real Soon Now

Harald

[don]

Thanks Harald. You've been holding out on us!

Do you have a list of new Celx methods that I can at least search the source code for, write a test script, and then add to my RTF file? Or should I just browse the celx.cpp source file?

Thanks again.

[jestr]

Hi Straight,you can find 2 different versions of Stonehenge here
http://jestraddons.250free.com/
Version 1 is for older versions of Celestia and version 2 is for Celestia 1.3.2 pre 6 or higher.They are the same model just ssc is different,hope you like it,it is best with my level10 Earth texture(level10 for south britain that is not the whole Earth)but my FTP is not working at the moment I think you may be able to get it from Psykotiks excellent website though.Jestr

[straight]

Wow, thanks, Jestr! Those moon models and textures you've made are spectacular.

Are the brighter colors artistic license, or are they based on actual photos?

[jestr]

Artistic license ,Jestr