Planetshine

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krypton
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Planetshine

Post #1by krypton » 25.05.2013, 20:13

Not quite sure this is a bug, but this only happens to one planet.
What determines the amount of planetshine?
I have ambient light set to none. All my planets generate a very dim planetshine, which is great. It looks correct. But I have one planet whose planetshine is almost equal to direct sunlight on every one of its moons.
You're looking at the night side of the moon...the side facing away from the sun and towards the planet. Is this a bug, or am I doing something wrong?

Planetshine.jpg

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John Van Vliet
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Re: Planetshine

Post #2by John Van Vliet » 25.05.2013, 20:52

--- edit----
Last edited by John Van Vliet on 18.10.2013, 11:22, edited 1 time in total.

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krypton
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Re: Planetshine

Post #3by krypton » 25.05.2013, 22:03

Windows 7

There is no alpha channel or specular setting to the moon texture. Incidentally, this is only one of several textures I tried on this moon since, at first, I thought it might be the texture. I've even tried different textures on the planet but the same effect occurs on any moon facing its sunlit side.

I'm using an Nvidia GTX 260 card.

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krypton
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Re: Planetshine

Post #4by krypton » 26.05.2013, 06:33

Hi lodgy,

There is only one star in the .stc file.

Whenever any moon is on the sunlit side of the planet, the side of the moon facing the planet will light up as well as the side facing the sun.

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krypton
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Re: Planetshine

Post #5by krypton » 26.05.2013, 06:40

I checked to make sure the planet was not emissive, and it's not. But even if it were...emissive objects don't really emit light, do they? They just look bright and don't have shadows, right?

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krypton
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Re: Planetshine

Post #6by krypton » 26.05.2013, 18:34

Hi Olyv,

Here's the planet:

"Archeon" "HIP 500273"

{
Texture "Archeon.jpg"
NightTexture "Magnetic_Blue.png"
Radius 37277
Oblateness 0.0352
Color [ 0.2 0.6 0.9 ]

EllipticalOrbit

{
Period 36.3473
SemiMajorAxis 11.0021
Inclination 4.1325 # Orbit tilt
Eccentricity 0.1108
}

UniformRotation

{
Period 31.1692
Inclination 15.6888 # Axis tilt
}

Albedo 0.4
}



Here's one of the moons. Remember, it's not just one certain moon that shows this effect. Any of the nearer moons show this effect when they're on the day side of the planet. But just for reference, here's the moon shown in the images above.

"Lusit:Archeon 2" "HIP 500273/Archeon"

{
Texture "Archeon2.jpg"
BumpMap "Archeon2Bump.jpg"
BumpHeight 1
Radius 1547

EllipticalOrbit

{
Period 2.8172
SemiMajorAxis 328665
}

Albedo 0.5
}


Not sure if this has any bearing, but the ssc file was originally written in WordPad. I use Notepad ++ now. It seems strange to me that only one of the ten planets shows this effect on its moons. But then who knows? Maybe I'll re-write the ssc file from scratch in Notepad ++ when I have time.

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John Van Vliet
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Re: Planetshine

Post #7by John Van Vliet » 26.05.2013, 19:33

--- edit----
Last edited by John Van Vliet on 18.10.2013, 11:22, edited 1 time in total.

Topic author
krypton
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Re: Planetshine

Post #8by krypton » 26.05.2013, 21:44

Hmm. Changing the color values didn't change anything, but I think I found the problem, although I don't understand why it's doing it.
There is a .3DS mesh around the planet containing a .png image of a forming ring. When I remove it as follows:

#"Corona C" "HIP 500273/Archeon"
#
#{
# Mesh "planar5.3ds"
# Texture "planar005.png"
# Emissive true

the bright "planetshine" is gone. If I leave it there, with emissive "true" or emissive "false", the bright planetshine appears. I thought emissive objects were not supposed to cast any light on any other object.

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John Van Vliet
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Re: Planetshine

Post #9by John Van Vliet » 26.05.2013, 22:17

--- edit----
Last edited by John Van Vliet on 18.10.2013, 11:21, edited 1 time in total.

Topic author
krypton
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Re: Planetshine

Post #10by krypton » 26.05.2013, 23:53

john Van Vliet wrote:you do not need a mesh for a ring

look and Saturn as an example

I know.
It's not a ring....yet :wink:
It's a swirling dust cloud.

Topic author
krypton
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Re: Planetshine

Post #11by krypton » 27.05.2013, 06:38

lodgy,


Thanks for the link. That's a very interesting thread.
It still doesn't explain why the mesh is casting so much light, and it does it whether the emissive expression is set to True or False. But I can live with it. At lease I know where it's coming from and that it's not something on my part like a misspelling in the .ssc file.
I'll have to experiment with sprites one of these days. In the meantime, I got the effect I was looking for...a ghostly swirl. Edge on, it looks like a faint ring. From the top, it's barely discernible.


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