Rings...

Tips for creating and manipulating planet textures for Celestia.
Topic author
Dollan
Posts: 1150
Joined: 18.12.2003
Age: 54
With us: 20 years 11 months
Location: Havre, Montana

Rings...

Post #1by Dollan » 25.10.2004, 00:07

This might be hoping too much, but...

Is there a generator somewhere that creates random ring textures? I just can't seem to get the hang of making them....

...John...
"To make an apple pie from scratch, you must first create the universe..."
--Carl Sagan

Michael Kilderry
Posts: 499
Joined: 11.10.2004
With us: 20 years 1 month
Location: London, UK

Post #2by Michael Kilderry » 25.10.2004, 07:20

I don't think the rings of the planets in your ArcBuilder's Universes look that bad, unless your using other people's ring textures, I'd say that youre not that bad at making ring textures. Ring textures aren't that hard to for me to make, but they can have unpredictable results :).

I do not know of a generator that creates random ring textures, but your free to borrow the ring textures from my addon, The Lera Solar System!

Michael Kilderry :)
My shatters.net posting milestones:

First post - 11th October 2004
100th post - 11th November 2004
200th post - 23rd January 2005
300th post - 21st February 2005
400th post - 23rd July 2005

First addon: The Lera Solar System

- Michael

Evil Dr Ganymede
Posts: 1386
Joined: 06.06.2003
With us: 21 years 5 months

Post #3by Evil Dr Ganymede » 25.10.2004, 07:51

I can't help you on the random rings front, but you might get some useful info out of Bjorn Jonsson's Saturn Rings page

Topic author
Dollan
Posts: 1150
Joined: 18.12.2003
Age: 54
With us: 20 years 11 months
Location: Havre, Montana

Post #4by Dollan » 25.10.2004, 14:34

Yeah, the ring textures are borrowed, gathered ages ago from varous sources before I started my add-ons. I've been trying to make them from scratch since I started my project, but with horrific results.

I'll keep searching for a tutorial. I must have missed one somewhere.

...John...
"To make an apple pie from scratch, you must first create the universe..."
--Carl Sagan

Avatar
selden
Developer
Posts: 10192
Joined: 04.09.2002
With us: 22 years 2 months
Location: NY, USA

Post #5by selden » 25.10.2004, 15:59

John,

Google is your friend :)

Search for
planet rings tutorial
e.g.
http://www.deviantart.com/view/9266496/
http://www.solarvoyager.com/tutorials.asp

Celestia would use one radial row of pixels from one of these images.

Alternatively, you could create a translucent ring model and define it as a planet, specifying exactly the same orbital parameters as the planet it "orbits". There are some translucency bugs in Celestia v1.3.2 that might cause problems, though.
Selden

Evil Dr Ganymede
Posts: 1386
Joined: 06.06.2003
With us: 21 years 5 months

Post #6by Evil Dr Ganymede » 25.10.2004, 16:24

Selden - the rings tutorial on that Solar Voyager site is really cunning :).

That looks like a great site in general... must peruse that more later!

Avatar
selden
Developer
Posts: 10192
Joined: 04.09.2002
With us: 22 years 2 months
Location: NY, USA

Post #7by selden » 25.10.2004, 16:30

Oh Evil One,

Well, that particular example produces a spiral instead of concentric rings, but presumably that's easily fixed. The idea of using a cloud generateor does sound appropriate.

http://www.SolarVoyager.com does seem to be one of the better space-art sites.
Selden

Avatar
Cham M
Posts: 4324
Joined: 14.01.2004
Age: 60
With us: 20 years 10 months
Location: Montreal

Post #8by Cham » 25.10.2004, 16:51

Spiral rings may be interesting. I've tried to make some for a black hole, but I didn't succeed. Is there a way to have a spiral ring in Celestia, with the Ring command, without using a mesh around a planet ?
"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!"

Topic author
Dollan
Posts: 1150
Joined: 18.12.2003
Age: 54
With us: 20 years 11 months
Location: Havre, Montana

Post #9by Dollan » 25.10.2004, 18:05

**grumps** Some aspects of my Photoshop are jsut different enough to cause problems I suppose fiddling around with it will bring understanding, though. I've been Googling, though, looking for a Celestia-specific tutorial, but haven't found one yet.

Still, I'm closer than I was before. Thanks, guys!

...John...
"To make an apple pie from scratch, you must first create the universe..."
--Carl Sagan

Avatar
selden
Developer
Posts: 10192
Joined: 04.09.2002
With us: 22 years 2 months
Location: NY, USA

Post #10by selden » 25.10.2004, 18:24

John,

I'm sure there's no tutorial specfically for Rings in Celestia.

Rassilon might have some suggestions. I suspect he's created some for his various large planetary systems.

My own crude suggestion would be to generate an image of lots of tiny clouds which contains an opacity channel (up to 2K wide for Radeons, up to 4K wide for Nvidia cards) and cut a single scanline from that to use as your Ring texture. Swirling it, as suggested on the SolarVoyager site, would increase the apparent number of individual narrow rings.

Of course, the "right" way to do it would be with a numeric simulation that takes into account all the moons of your planet.
Selden

ajtribick
Developer
Posts: 1855
Joined: 11.08.2003
With us: 21 years 3 months

Post #11by ajtribick » 25.10.2004, 19:48

Personally I've got ok results out of using POV-ray's bozo texture, like this image. It shouldn't be too hard to rig something up to output a ring texture file, an orthographic camera projection should do the trick.

Evil Dr Ganymede
Posts: 1386
Joined: 06.06.2003
With us: 21 years 5 months

Post #12by Evil Dr Ganymede » 25.10.2004, 21:11

Wow. Did you render that entirely in POVRay? I'd love to know how you did that. (if you're willing to share, please PM me!)


Return to “Textures”