a disk in the sun

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skodella
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a disk in the sun

Post #1by skodella » 27.09.2009, 13:09

Hi, i have a problem: everytime i put an alternative texture on a star, for example our Sun, a darker disk is appearing in the center of the globe and I don't know how to remove it. I attached a picture just to make you see better. The addon I've aplicated here is "smaller_sun.zip" I've downloded from celestia motherlode. The same thing happened when I tried to changhe Betelgeuse texture. A disk appears in the middle of the star. I hope you can help me. Excuse me for my english that's not so fluent since I'm an italian boy. Thanks

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selden
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Re: a disk in the sun

Post #2by selden » 27.09.2009, 15:05

Which version of Celestia are you running?
Which Star Style do you have selected? (Type Ctrl-S several times to step through them)
Which Render Path do you have selected? (Type Ctrl-V several times to step through them)
Selden

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selden
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Re: a disk in the sun

Post #3by selden » 27.09.2009, 15:38

I've managed to reproduce it.

Runar's Addon was created for an older version of Celestia.
What you are seeing is the planet that Runar defined to carry the re-defined Sun Texture.
(It's much more obvious if you comment out the "Emissive true" statement in the SSC file.)

That trick is no longer necessary.

To apply a texture to a star when using Celestia v1.6.0, create an STC catalog containing the appropriate Texture statement. To change the surface texture of an existing star, you can use Modify.

For example, this .STC catalog works for Celestia v1.6.0

suntexture.stc

Code: Select all

Modify "Sun" { Texture "th_sun.*"}


Below is what this looks like on my system.
Selden

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selden
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Re: a disk in the sun

Post #4by selden » 27.09.2009, 16:00

But I do think it has to be considered a bug in Celestia :(

Celestia should not draw it that way.
Selden

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skodella
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Re: a disk in the sun

Post #5by skodella » 27.09.2009, 16:30

Thanks Selden, I tried everithing you said, I use Celestia v1.6.0, I stepped through the Render Paths and stars styles, but nothign changed. I also tried to create the catalog, but then again no.I will uninstall this addon and search for another one that fits my version of the software. Thank you again, but anyway I still wonder how you made it!

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cartrite
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Re: a disk in the sun

Post #6by cartrite » 27.09.2009, 17:12

I tried this addon. I think it was the same addon. It was the small one that was modified to be smaller.
Smaller_sun.zip
I didn't see anything. The addon was ignored. Then I created a new file called sun.stc with the one entry selden posted. I created it in the "th_sun" folder. Then everything worked fine.
Actually, after taking a second look, the addon wasn't totally ignored. The solar flares all loaded. Just the texture was ignored. But after the .sct file was created, the texture loaded.
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Last edited by cartrite on 27.09.2009, 17:23, edited 1 time in total.
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selden
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Re: a disk in the sun

Post #7by selden » 27.09.2009, 17:15

skodella,

Here's an Addon which shows what I did.

It uses Modify in an STC file to provide a new surface texture for our Sun. It uses and includes a jpg version of Runar's texture.
Selden

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Re: a disk in the sun

Post #8by cartrite » 27.09.2009, 17:32

Maybe this is a bug. I tried the KDE version and everything "looked" ok. But when I tried it in the QT4 version, this is what I saw.
the-sun.jpg

It seems that my QT4 version had star style set to scaled discs. So when I tried the KDE version again, I set the star style to scaled discs and saw the same thing. I type h, then g, then I zoom out a little.
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selden
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Re: a disk in the sun

Post #9by selden » 28.09.2009, 11:01

Runar's Addon has several components. What you're seeing is the glow of their individual albedo values.

Since there are no Albedo specifications in the SSC file, recent versions of Celestia provide a non-zero default Albedo which makes them glow with a white halo. Adding Albedo values of 0 or defining the parts as Class "component" would eliminate the problem when the Addon is used with Celestia v1.6.0.
Selden

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skodella
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Re: a disk in the sun

Post #10by skodella » 28.09.2009, 16:59

Thanks for your help Selden, but it still does not work. I tried your sun_texture.zip. I simply unzipped the file and put the sun_texture folder in the addons and all worked fine: I modified the texture of our sun. Then I deleted it and tried to do the same with smaller_sun.zip. I put the unzipped th_sun folder into addons folder and added the .stc file with the entry above (Modify "Sun" { Texture "th_sun.*"}). I previously created it and named it "th_sun.stc", put into the th_sun folder. I started Celestia and...I obtained the same result: the disk was still there. I think this is a bug. Or maybe it depends on my ATI RADEON 7000 SERIES graphic card that is not a very powerfull one, I Know Celestia works better with OPenGL and Nvidia graph. cards...
It's a pity because th_sun had animated solar eruptions, anyway now I'm using your sun_texture and enjoy it.

Still forgive me for my bad english

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selden
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Re: a disk in the sun

Post #11by selden » 28.09.2009, 17:16

skodella,

Runar provided a fix on the MotherLode for the problem.
Goto the Web page http://www.celestiamotherlode.net/catalog/sol.php
Download "Patch for Celestia 1.5/1.6"
It's under the "smaller version"
Or you can use this link:
http://www.celestialmatters.org/users/r ... update.zip

This update includes a new th_sol.stc and a replacement th_sun.ssc
Put them both in the folder th_sun.

This change fixed the problem for me. I hope it will fix the problem for you.
Selden

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skodella
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Re: a disk in the sun

Post #12by skodella » 28.09.2009, 17:16

Ok! I nearly made it. I was able to make Celestia read the texture file. If I put the catalog file in the folder and eliminate the .ssc file at the same time, Celestia modify the texture, but obiouvsly I lose all the rest. So, I should create the .stc file and then modify something in the .ssc file. I'll give it some try

Topic author
skodella
Posts: 5
Joined: 27.09.2009
With us: 15 years 1 month

Re: a disk in the sun

Post #13by skodella » 28.09.2009, 17:26

what a...the solution was just rigth there under my eyes. Yes, it works, fine! Thanks... :roll:


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