Celestia Forums

Greetings from Brazil,

First of all, I apologize for my poor english...

Celestia is great! Congratulations for its creator and all the colaborators.

Now the question:

I've just upgraded from Celestia 1.3.1 to 1.3.2. I know that irregular bodies do not cast shadows on planets. But in Celestia 1.3.1, the planets did cast shadows on their irregular moons (like Jupiter's shadow in Amalthea, for example). They were not quite perfectly rendered but were fine to me. For my surprise, in Celestia 1.3.2 this does not happen (at least in my computer)! Repeating the example above, when Amalthea passes behind Jupiter, the irregular shaped moon was still iluminated by the sun, as if Jupiter was transparent (and I'm sure the option for showing eclipses was selected).
I need help here. Is it a bug or am I doing something wrong?

My system:
AMD 2.2GHz
512MB RAM
NVidia GeForce4 MX440-8X, 64MB DDR (no ring shadows... )

I look forward for your reply,
Thanks

Fafers

I also experience this problem... Amalthea is never shadowed by Jupiter

Celestia v1.3.2, Windows version (using WinXP Home), NVIDIA GeForce 3 Ti200 card

The eclipses for these objects were turned off some time ago, since they had become mysteriously badly behaved ... objects were turning emissive for no good reason. I presume Chris has so far been unable to find the bug.

Grant

Eclipses shadows on irregular objects never worked right as far as I know. I understand what needs to be done to make them work; these changes will be part of the work I do to enable bump, specular, and night textures for mesh objects.

--Chris

Hi,

Thanks for your replies!

Chris,

I understand that they never worked right but in 1.3.1 there was, at least, some kind of shadow while in 1.3.2 there isn't any...
But it's ok! It's just a small detail in a great software. I'll wait for the upgrades.

bye!
Fafers

chris wrote:Eclipses shadows on irregular objects never worked right as far as I know. I understand what needs to be done to make them work; these changes will be part of the work I do to enable bump, specular, and night textures for mesh objects.

--Chris

Just thought I'd add my two cents worth concerning eclipse shadows...

Am still using 1.3.2 Pre11 and can no longer see eclipses on ANY of the
planets, regardless of which moon should be creating the eclipse shadow.

All I'm seeing now (via my Intel graphics chip) is a series of ugly, black
artifacts where the eclipse shadows should be.

Anything I should know about in order to correct the problem?

Cannot update my openGL drivers any further since Intel hasn't updated
them since 2002. Also experimented with turning on/off the Vertex Shaders
to no effect.

Any ideas?

Thanks, Bob

Another two cents worth for those who care...

As per Selden's advice (Thanks *very* much Mr. Ball!) I disabled my
Intel graphics accelerator chip and tried to view an eclipse shadow on the
Earth via Ulrich's - a.k.a Adirondack - Eclipse on Earth cel script.

Although I no longer see the stationary, ugly, triangular black artifacts
under the Windows OpenGL, I can *still* see no eclipse shadows
rendered on the Earth. I *do* manage to see some very faint cloud-type
dark shadows on the planet's surface, but the eclipses still do not work
correctly.

Just thought I'd mention it.

Thanks, Bob

Below are the different types of shadows drawn by Celestia for the 2006 African solar eclipse when using Celestia's different "Render Paths" and an Nvidia FX5200 graphics card.

Although they do show that an eclipse is happening, I'm sorry to say that the shadows aren't all that great. Hopefully the imagry for all of the Paths will be improved in a future version of Celestia.

(Each of the thumbnails below links to a larger picture.)


Basic Render Path



Multitexture Render Path


Nvidia Combiners Render Path


OpenGL Vertex Program Render Path


OpenGL + Nvidia Combiners Render Path


Nvidia FX Render Path

System:
512MB 2.4GHz P4, WinXP Pro SP2
128MB FX5200, Forceware v61.76
Celestia v1.3.2 final