White dots

The place to discuss creating, porting and modifying Celestia's source code.
Topic author
chrisr
Posts: 62
Joined: 21.08.2003
With us: 21 years 3 months
Location: AZ

White dots

Post #1by chrisr » 29.08.2004, 06:12

Why do all objects beome white dots when you zoom out from them? When will this be corrected?
Just do what makes you happy provided you do not infringe on another's happiness for there is no point in living if you do not have happiness.
[tex]Happiness = \[\int_a^b \int_c^d \int_e^f \int_g^h U(x,y,z,t)\,dx dy dz dt\] = 42[/tex]
If only we knew U!

chris
Site Admin
Posts: 4211
Joined: 28.01.2002
With us: 22 years 9 months
Location: Seattle, Washington, USA

Re: White dots

Post #2by chris » 29.08.2004, 18:03

chrisr wrote:Why do all objects beome white dots when you zoom out from them? When will this be corrected?


What would you expect to see instead?

--Chris

Kendrix
Posts: 159
Joined: 02.06.2002
With us: 22 years 5 months
Location: near Paris, France
Contact:

Post #3by Kendrix » 30.08.2004, 00:58

I think that for example : remember last year the Mars opposition ?
In the sky Mars wasn't a white dot but a (bright) ORANGE dot !

granthutchison
Developer
Posts: 1863
Joined: 21.11.2002
With us: 22 years

Post #4by granthutchison » 30.08.2004, 01:04

Kendrix wrote:I think that for example : remember last year the Mars opposition ?
In the sky Mars wasn't a white dot but a (bright) ORANGE dot !

Mars is an orange dot in Celestia, too ... that's what the Color statement does.

Grant

unloggedchrisr

fa

Post #5by unloggedchrisr » 03.09.2004, 02:22

well i would expect it to disapear. Especially if the sun were behind it. If the sun is in the foreground this makes perfect sense. This brings up another idea. Will celestia ever incorporate contrast. Like not being able to see the other stars when the sun is in the field of view!

Slalomsk8er
Posts: 128
Joined: 26.07.2004
With us: 20 years 4 months
Location: Earth 7.593358long / 47.582393lat
Contact:

Post #6by Slalomsk8er » 03.09.2004, 13:37

And galaxies are even made briter by the flare of the suns!

maxim
Posts: 1036
Joined: 13.11.2003
With us: 21 years
Location: N?rnberg, Germany

Post #7by maxim » 03.09.2004, 20:55

Slalomsk8er wrote:And galaxies are even made briter by the flare of the suns!

That's an old problem.
I think it arises from a treatment of textures with an additive color concept instead of an subtractive one. There seems to be no division of textures into emissive and non emissive ones - so (overlay) textures on planet surfaces and deep space textures are treated the same way.

Of course it is ok in reality that a star adds it's light to a sun corona or nebula to make it brighter - unfortunately there are massive dynamic range restrictions on monitors that should turn this into negation for a proper display.

Perhaps Chris has this already on it's list ???

maxim

Rassilon
Posts: 1887
Joined: 29.01.2002
With us: 22 years 9 months
Location: Altair

Post #8by Rassilon » 03.09.2004, 23:38

A billboard of a black disk with gradient edges could be placed or rendered behind the star model and the billboard of the flare to remove the galaxies and nebs out of the suns corona. Im willing to bet this would have to be a shadow map.

The other should be easy to fix with a bit of programming I suppose...
I'm trying to teach the cavemen how to play scrabble, its uphill work. The only word they know is Uhh and they dont know how to spell it!

Seb
Posts: 44
Joined: 12.09.2004
With us: 20 years 2 months
Location: Wiltshire, UK

Post #9by Seb » 12.09.2004, 15:46

(ive said this before, but) I think Celestia should calculate what the real world luminosity of each object & textures. Then adjust the output to the screen as make things visible, like a camera or the human eye would do.

As each object is rendered to the screen, the brightness values found could be analysed as to find an ideal exposure value, this can then be used to as to adjust the next rendered screen. The eye can take a number of seconds to find the ideal exposure settings, so getting to the ideal value doesn’t have to be instant.

(for those who don’t understand what I mean, found some details on luminosity histograms here: http://www.megapixel.net/cgi-bin/fs_loa ... ogram.html)


Return to “Development”