Scaled discs brightness

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Topic author
Mariusz Kuźmiński
Posts: 21
Joined: 02.07.2012
With us: 12 years 4 months

Scaled discs brightness

Post #1by Mariusz Kuźmiński » 05.09.2012, 13:39

Hello, I'm using "scaled discs" mode to render stars, but even with bright textures they seem too dark for me. Is it possible to make them more luminous by change of any parameters? I found buildstardb.pl file, but it contains infos about B-V factor mainly. Maybe any way? :?

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t00fri
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With us: 22 years 7 months
Location: Hamburg, Germany

Re: Scaled discs brightness

Post #2by t00fri » 05.09.2012, 13:54

Mariusz Ku?mi?ski wrote:Hello, I'm using "scaled discs" mode to render stars, but even with bright textures they seem too dark for me. Is it possible to make them more luminous by change of any parameters? I found buildstardb.pl file, but it contains infos about B-V factor mainly. Maybe any way? :?

There is a range of star brightness adjustment available via the "[" and "]" keys. I suppose you exploited that option already? (With some knowledge of the sources, it is VERY easy to increase that range)

Are you sure that you did correctly adjust your monitor? There is special software for that depending on your OS.

The scaled disc star model is a very bad approximation to account for the large range of star brightness on typically low-dynamics monitors. Eventually so-called "shader stars" should be implemented, as existing in form of a patch by ChrisL

viewtopic.php?f=10&t=16031&start=0

or as a regular feature in my forthcoming celestia.Sci.

viewtopic.php?f=3&t=16981&start=4
The "shader stars" combine a varying (OGL) pointsize with a (possible) Gaussian halo to increase the renderable range of brightness. Below a certain threshold brightness, stars have no halos. These sophisticated stars are implemented by means of the fast OGL shader technology. Hence the name.

After patching the sources, one needs to recompile, however. There are several discussions about these much better stars in this forum. See the first link and/or use the search engine.

Fridger
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Topic author
Mariusz Kuźmiński
Posts: 21
Joined: 02.07.2012
With us: 12 years 4 months

Re: Scaled discs brightness

Post #3by Mariusz Kuźmiński » 06.09.2012, 19:57

t00fri wrote:There is a range of star brightness adjustment available via the "[" and "]" keys. I suppose you exploited that option already?
Yes, I have tried that adjustment, but it doesn't increase or decrease luminosity of big disc, as seen from small distance. However, I'm looking forward additional features in new Celestia :)

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John Van Vliet
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Re: Scaled discs brightness

Post #4by John Van Vliet » 07.09.2012, 00:30

--- edit ---
Last edited by John Van Vliet on 19.10.2013, 04:37, edited 1 time in total.

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t00fri
Developer
Posts: 8772
Joined: 29.03.2002
Age: 22
With us: 22 years 7 months
Location: Hamburg, Germany

Re: Scaled discs brightness

Post #5by t00fri » 07.09.2012, 07:14

john Van Vliet wrote:so that there is no confusion
t00fri's Celestia.Sci
is NOT the up and coming Celestia 1.7.0

As far as I can tell there is NO "up and coming Celestia 1.7.0"
while there indeed exists a 1.7.0 branch in SVN

it is a very different fork of celestia

Celestia 1.6.1 is currently the official version
http://www.celestiaproject.net/celestia/download.html
or the current SVN pull is basically 1.7.0

That's correct, and there are NO attempts made yet in the 1.7.0 branch of implementing a satisfactory rendering of stars.

Fridger
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