Subject line says "off the shelf" because it was first made almost two years
ago and then left to sit idle. Now trying it in the 3.6 beta and making some
texture and environment changes. It will definitely need a realistic Earth
mapped onto that sphere at the horizon.
:-)
Getting black areas and specks on it from something, can't figure out why.
The max_trace_level is at a low 9 but there's not much reason for it to be
higher. Wouldn't expect so. In fact, I was finding a really odd black
splotch on the ground plane (other grass earth one) when using radiosity,
however this one doesn't use that. But it does have a isosurface instead of
plane for the ground. This model caused trouble last time I was working with
it too, with the inside apparently leaking through to the outside. Whether
my fault or POVs...? I sure hope to figure that out someday.

Oh yeah, someone might ask what function the Moon surface is made from. It's
a f_ridge() from functions.inc. If anyone wants to ask or say anything, I'll
reply back eventually.

Bob H.

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Hughes, B. wrote:
> Subject line says "off the shelf" because it was first made almost two years
> ago and then left to sit idle. Now trying it in the 3.6 beta and making some
> texture and environment changes. It will definitely need a realistic Earth
> mapped onto that sphere at the horizon.
> :-)
> Getting black areas and specks on it from something, can't figure out why.
> The max_trace_level is at a low 9 but there's not much reason for it to be
> higher. Wouldn't expect so. In fact, I was finding a really odd black
> splotch on the ground plane (other grass earth one) when using radiosity,
> however this one doesn't use that. But it does have a isosurface instead of
> plane for the ground. This model caused trouble last time I was working with
> it too, with the inside apparently leaking through to the outside. Whether
> my fault or POVs...? I sure hope to figure that out someday.
>
> Oh yeah, someone might ask what function the Moon surface is made from. It's
> a f_ridge() from functions.inc. If anyone wants to ask or say anything, I'll
> reply back eventually.

Oh YEAH -- fantastic!
It reminds me of Wallace and Grommit.
"Cheese, Grommit! We need cheese! Cheese!!!!"

Another parallel light at low intensity pointing down from behind the 
object will bring out the details of the shadow and add depth.

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"Dan P" <dan### [at] yahoocom> wrote in message
news:407f1de5@news.povray.org...
> Hughes, B. wrote:
> > Subject line says "off the shelf" because it was first made almost two
years
> > ago and then left to sit idle.
>
> Oh YEAH -- fantastic!
> It reminds me of Wallace and Grommit.
> "Cheese, Grommit! We need cheese! Cheese!!!!"

Ha ha! Thanks Daniel, that's a compliment. Someone said that last time I
posted it, IIRC.

> Another parallel light at low intensity pointing down from behind the
> object will bring out the details of the shadow and add depth.

Ahh, an oversight. I haven't added a light shining back from the Earth yet!
That might do it. Although, probably not high up enough to illuminate the
upper parts of the CS. There already is a shadowless light directly above
but it's extremely dim. Originally I was never intending to have any other
illumination besides the sunlight, and moon surface diffusing onto it by
using radiosity.

The Earth doesn't really add anything by radiosity alone so I'll add a light
source to it.

Bob H.

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Hughes, B. nous apporta ses lumieres ainsi en ce 2004/04/16 16:10... :

>"Dan P" <dan### [at] yahoocom> wrote in message
>news:407f1de5@news.povray.org...
>  
>
>>Hughes, B. wrote:
>>    
>>
>>>Subject line says "off the shelf" because it was first made almost two
>>>      
>>>
>years
>  
>
>>>ago and then left to sit idle.
>>>      
>>>
>>Oh YEAH -- fantastic!
>>It reminds me of Wallace and Grommit.
>>"Cheese, Grommit! We need cheese! Cheese!!!!"
>>    
>>
>
>Ha ha! Thanks Daniel, that's a compliment. Someone said that last time I
>posted it, IIRC.
>
>  
>
>>Another parallel light at low intensity pointing down from behind the
>>object will bring out the details of the shadow and add depth.
>>    
>>
>
>Ahh, an oversight. I haven't added a light shining back from the Earth yet!
>That might do it. Although, probably not high up enough to illuminate the
>upper parts of the CS. There already is a shadowless light directly above
>but it's extremely dim. Originally I was never intending to have any other
>illumination besides the sunlight, and moon surface diffusing onto it by
>using radiosity.
>
>The Earth doesn't really add anything by radiosity alone so I'll add a light
>source to it.
>
>Bob H.
>
>
>  
>
You're on the moon, that mean NO air -> shadows are SUPOSED to be pitch 
black. I remember the Apolo lunar expeditions, unless there is something 
nearby to reflect light into a shadowed area, there was absolutely 
nothing to be seen but black.
The shadowless light must be extremely dim, it represent star's light, 
globaly, that's less than about 0.001% that of the sun.

Alain

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In article <408097cb$1@news.povray.org>, Alain <aze### [at] qwertygov> 
wrote:

> You're on the moon, that mean NO air -> shadows are SUPOSED to be pitch 
> black. I remember the Apolo lunar expeditions, unless there is something 
> nearby to reflect light into a shadowed area, there was absolutely 
> nothing to be seen but black.

Your argument has actually been used to claim the moon photos were 
fake...but it's wrong. There *was* something to reflect the light...the 
ground, which happens to be covered in dust which is unusually good at 
reflecting light back in the general direction it came from. In most of 
the images I've seen, this was quite clear...the surrounding brightly 
lit surface would diffuse light onto the shadowing object, which would 
diffuse light onto the shadowed part of the surface. The shadowed side 
of the object would be fairly well lit, and the ground shadow dimly lit. 
Only areas shadowed both from the sun and from the ground were really 
dark.

http://www.iangoddard.net/moon01.htm


> The shadowless light must be extremely dim, it represent star's light, 
> globaly, that's less than about 0.001% that of the sun.

Starlight would be negligible, even without the atmosphere to block it. 
Earthlight could be quite bright at night, however. Think of how bright 
nights with full moons can be, and consider that Earth is about 3.67 
times as big as the moon. (though the lower albedo will compensate 
somewhat)

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/

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Hughes, B. wrote:

> "Dan P" <dan### [at] yahoocom> wrote in message

<snip/>

>>Oh YEAH -- fantastic!
>>It reminds me of Wallace and Grommit.
>>"Cheese, Grommit! We need cheese! Cheese!!!!"
> 
> 
> Ha ha! Thanks Daniel, that's a compliment. Someone said that last time I
> posted it, IIRC.

Heh! Cool!

>>Another parallel light at low intensity pointing down from behind the
>>object will bring out the details of the shadow and add depth.

> Ahh, an oversight. I haven't added a light shining back from the Earth yet!
> That might do it. Although, probably not high up enough to illuminate the
> upper parts of the CS. There already is a shadowless light directly above
> but it's extremely dim. Originally I was never intending to have any other
> illumination besides the sunlight, and moon surface diffusing onto it by
> using radiosity.

Sweet.

> The Earth doesn't really add anything by radiosity alone so I'll add a light
> source to it.

Right; it's too far away.
Very cool scene!

> Bob H.
> 
>

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Alain wrote:

> Hughes, B. nous apporta ses lumieres ainsi en ce 2004/04/16 16:10... :

<snip/>

> You're on the moon, that mean NO air -> shadows are SUPOSED to be pitch 
> black. I remember the Apolo lunar expeditions, unless there is something 
> nearby to reflect light into a shadowed area, there was absolutely 
> nothing to be seen but black.
> The shadowless light must be extremely dim, it represent star's light, 
> globaly, that's less than about 0.001% that of the sun.
> 
> Alain

Ack, forget accuracy. Did Lucas let the tiny detail that ships can't 
bank in space because there's no air stop him? No, man, he said, like, 
"It's my freekin' universe and I'll phyisicalize it as I want!" :-)

--
Dan P
http://<broken link>

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In article <4081ceec$1@news.povray.org>,
 Dan P <dan### [at] yahoocom> wrote:

> > The Earth doesn't really add anything by radiosity alone so I'll add a light
> > source to it.
> 
> Right; it's too far away.

Distance has little to do with it, it is the area of sky covered and 
brightness per unit area that counts. The diameter is about 3.6 times 
that of the moon, the sky area covered is almost 13.5 times greater. The 
moon's albedo is less than Earth's, between 7% and 12% compared to 30%. 
(The lunar surface reflects light preferentially in the direction it 
came from, so it appears brighter when nearly full.)

This all means that Earthlight is much brighter than moonlight. It's 
still very little in comparison to direct sunlight, but it can 
contribute to shadowed areas if the viewer's not looking at a bright 
object, and will be very significant at night on the near side. And it's 
practically all due to radiosity, diffusely scattered sunlight, though 
an area light might be more accurate than any but very high radiosity 
settings.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/

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Among other things, Christopher James Huff wrote:

>> > The Earth doesn't really add anything by radiosity alone so I'll add a
>> > light source to it.
>> 
>> Right; it's too far away.
> 
> Distance has little to do with it, it is the area of sky covered and
> brightness per unit area that counts.

Is this true? I mean, in POV world, doesn't distance really matter when 
computing radiosity?

> This all means that Earthlight is much brighter than moonlight. It's
> still very little in comparison to direct sunlight, but it can
> contribute to shadowed areas if the viewer's not looking at a bright
> object, and will be very significant at night on the near side. And it's
> practically all due to radiosity, diffusely scattered sunlight, though
> an area light might be more accurate than any but very high radiosity
> settings.

Yes. When the moon is very thin, you can clearly see the dark side lit by 
"earthlight". Even in a Moon eclipse, when all the moon is in shadow, and 
the earth face it sees is at night, the Moon is notably lit with a red 
glow, which comes from scattering in the Earth's atmosphere (all the dawns 
and twilights).

-- 
light_source{9+9*x,1}camera{orthographic look_at(1-y)/4angle 30location
9/4-z*4}light_source{-9*z,1}union{box{.9-z.1+x clipped_by{plane{2+y-4*x
0}}}box{z-y-.1.1+z}box{-.1.1+x}box{.1z-.1}pigment{rgb<.8.2,1>}}//Jellby

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In article <4084334d@news.povray.org>, Jellby <jel### [at] M-yahoocom> 
wrote:

> Is this true? I mean, in POV world, doesn't distance really matter when 
> computing radiosity?

As far as I know, it does so only when it comes to selecting previously 
taken samples to interpolate...you want to use samples taken from 
nearby, and probably reduce the importance of samples from more distant 
points. I don't know in detail how POV-Ray's radiosity algorithm works, 
though.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: <chr### [at] tagpovrayorg>
http://tag.povray.org/

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