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Release: A portrait of our Sun

Posted: 03.01.2005, 00:27
by rthorvald
A portrait of our Sun
----------------------------
I have made an add-on that replaces Sol. It features a hi-res virtual
texture in png format, detailed sunspots, and animated solar flares.

This is not an exact map of the sun - it??s really more of a portrait.
For one thing, it is much darker than the Celestia default g-star - i did this
to preserve detail (a brighter sun would burn out the granules). Also, i
have concentrated on creating a representation that *feels* real (to me,
anyway), rather than an exact map.

The Addon is based on real imagery, but in areas with very high
resolution (up to 128k on a particular sunspot), total ignorance of the
conditions down there is substituted with imagination ;-)

I was already busy inventing solar flares, when Cham suddenly published
a solution; he prepared a special package for me, and i have
incorporated it here (after a little customizing). Thank you for that!
Thanks also to Frank Gregorio, for permission to use the SSC file from his 2k Sun.

Here??s some screenshots:

Image
More info, screenshots and download links on my site.
Criticism is welcome.

- rthorvald

Posted: 03.01.2005, 03:24
by Cham
The sunspots are really impressive ! Good work !

A portrait of our Sun

Posted: 03.01.2005, 03:59
by Beowulf01
STELLAR!

Posted: 03.01.2005, 15:14
by mmarable
Holly cow! Fantastic work!

Can I ask about hot the flares are done? Or can you point me to where Cham posted his method?

Posted: 03.01.2005, 19:00
by bh
Great work here! Fantastic!

Regards...bh.

Posted: 03.01.2005, 20:15
by Boux
Simply superb...
My only comment if any...
Image

Posted: 03.01.2005, 20:58
by Dollan
Someday I'll have a system that can handle these absolutely remarkable creations of yours.... For now, the screenshots alone are worth it all!

...John...

Posted: 04.01.2005, 00:48
by maxim
Of course I have critics - as usual ;)

Well for the first - the artwork is fantastic. But ...
... the surface looks like an ordinal fluid - that means it reflects light instead of emitting it - but it is a plasma.
... for the same reason I don't like the ripples much - plasma is usually much more smoother.

So - only these two ones for now ;)

I would like to see the sources you used.

maxim

Posted: 04.01.2005, 01:24
by rthorvald
mmarable wrote:Can I ask about hot the flares are done?
Cham made a series of "Selden billboards" (two-dimensional 3ds meshes holding a semi-transparent picture), then made them orbit at different, eccentric paths partially inside the star. That way, parts of them stuck out of the star and dipped back in at (seemingly) irregular intervals.

I opted to use spheres instead, where the surface was a 100% transparent 3ds model, and the actual flare is drawn on a small part of a (sometimes) rotating cloudmap surrounding it. This method does not look as good as Cham??s 2-D one, but in return, it looks reasonable from any angle, while the 2-D approach makes the flare invisible if seen from the side.

So in short, in my sun, the flares is just moving cloudmaps on a bunch of invisible globes in Solar orbits Cham designed.

mmarable wrote:can you point me to where Cham posted his method?

Well, he demonstrated it in his Black Hole Add-On, on the Banquet star.

- rthorvald

Posted: 04.01.2005, 01:48
by rthorvald
maxim wrote:the surface looks like an ordinal fluid - that means it reflects light instead of emitting it - but it is a plasma.
... for the same reason I don't like the ripples much - plasma is usually much more smoother
I thought a lot about this; i almost decided to use two overlaying maps (using a 50% transparent cloudmap for the second layer) to have the entire surface appear fluid. But i would not be able to get this kind of resolution then, as (on my machine), the possible filesize of a cloudtexture is rather limited. So, i had to settle for a cloudlayer of soft, moving, highly transparent haze.

maxim wrote:I would like to see the sources you used

Well, i just looked at all the solar images i could find... One place where i got some major raw material is here: http://nsosp.nso.edu/. I??m not sure i have the rest of the links archived, though.

-rthorvald

Posted: 04.01.2005, 03:02
by Michael Kilderry
Amazing! I just can't fault it!

Michael Kilderry :)

Posted: 04.01.2005, 03:16
by fsgregs
Good Grief!!!!!!!

:D

Spectacular!

Frank

Re: Release: A portrait of our Sun

Posted: 04.01.2005, 11:50
by Guest
I have made an add-on that replaces Sol. It features a hi-res virtual texture in png format, detailed sunspots, and animated solar flares. rthorvald[/quote]
Rthorvald, it's absolutely astonishing, and will give the opportunity to realize a "Sun Tour" that up to-day was impossible, due to lack of images and details. :D
Thank you, thank you very much, sincerely! :wink:

Andrea :D

Posted: 04.01.2005, 14:25
by Kolano
Cham made a series of "Selden billboards" (two-dimensional 3ds meshes holding a semi-transparent picture), then made them orbit at different, eccentric paths partially inside the star. That way, parts of them stuck out of the star and dipped back in at (seemingly) irregular intervals.

I opted to use spheres instead, where the surface was a 100% transparent 3ds model, and the actual flare is drawn on a small part of a (sometimes) rotating cloudmap surrounding it. This method does not look as good as Cham??s 2-D one, but in return, it looks reasonable from any angle, while the 2-D approach makes the flare invisible if seen from the side.


Couldn't one have the billboards rotate in different directions, one north/south one east west (hrm I don't think thats quite the right way to put it), to preserve being able to see them from different angles?

Perhaps with your method you could put the orbs into elliptical orbits so that they would also merge into and out of the sun.

Re: Release: A portrait of our Sun

Posted: 04.01.2005, 19:04
by danielj
Very good,but I think there is a contradiction in the readme file.
You said that any detail beyond level 3 is imaginary.So levels 0-3 are real!In this case,the purists should delete levels 4-10 and not 2-10 as is written in the readme.Am I right?

Posted: 04.01.2005, 23:42
by fsgregs
Runar:

Just a question really. In looking at the flares/prominences moving, they seem to be moving really FAST across the sun. Within seconds, they have arced 180 degrees across a distance of thousands of km. That is what they look like in still frame capture video (which is always speeded up), but do they move that fast in real time? If not, lowering the rotation rate on each of the flares by a factor of 10 still allows them to move, but not quite so fast.

Just a suggestion for a super add-on. :)

Frank

Posted: 05.01.2005, 00:06
by rthorvald
Kolano wrote:Couldn't one have the billboards rotate in different directions [...] to preserve being able to see them from different angles?
They are two-dimensional, so at a 90 degree angle they will just vanish...

Kolano wrote:Perhaps with your method you could put the orbs into elliptical orbits so that they would also merge into and out of the sun.

They do :-)

-rthorvald

Re: Release: A portrait of our Sun

Posted: 05.01.2005, 00:09
by rthorvald
danielj wrote:You said that any detail beyond level 3 is imaginary.So levels 0-3 are real!In this case,the purists should delete levels 4-10 and not 2-10 as is written in the readme.Am I right?

Hum. I wrote that ReadMe too late in the night, i think. It has typos all over it.:evil:
It is "real" up to and including level 2. Anything beyond that is increasingly speculative.

-rthorvald

Posted: 05.01.2005, 00:22
by rthorvald
fsgregs wrote:In looking at the flares/prominences moving, they seem to be moving really FAST across the sun. Within seconds, they have arced 180 degrees across a distance of thousands of km.


Basically, the speeds are inherited from Cham??s data. I changed some details, just used speeds that gave me a reasonable viewing experience at normal time, but i didn??t go very far off. Maybe Cham can answer better than i.
I??ll be happy to mod the SSC file if this is badly off - and someone can give me a reality-check.


-rthorvald

Posted: 05.01.2005, 00:25
by Cham
I'm doing a rough calculation right now. I'll be back here in few minutes.