I follow the rule of finish{ambient 0} and it looks very dark to dull.
To make it look halfway like the original image I have to go the
light_source as  rgb<1,1,1>*3 and *5 isn't that bad. 

	OK, I am still missing something as that should not be necessary,
right? 

	And if it is necessary, what am I missing regarding the consistant
nature of the scene language? Was ambient originally a hack? 

	Attachment indented for the purist at heart. This is a side view that
will give essentially the effect I desire. 

	BTW: congrats, I guess, to the developer of the type 1 mapping for
first converting the image to a square or whatever the trick was to
avoid the need for scaling a rectangular image to a sphere. 

	And if you do not have a picture of the earth around to see the effect
it is simply the earth with a light and dark side and the shaded
transition from light to dark. Just stick in any image and look at the
lit hemisphere with *3 compared to *5 and see it is clearly less of half
than it should be. 

-- 
If there is anything that makes life complicated it is
trying to find decisions other than pragmatic. We appeal
to gods to make life hard. 
	-- The Iron Webmaster, 222

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Matt Giwer wrote:
> 
> If there is no
> illumination, why should anything be visible regardless of the ambient?
> I just want things to behave according to the scene description.

They *do* behave according to the scene description.

Ambient *is* illumination. It's directly added to whatever object(s) you
tell it to affect. In this case, since you've set the ambient of the
sphere to .5, the entire sphere is being illuminated by a constant,
directionless gray light. As someone else has mentioned, you could think
of it as "glowing".

If you were to shine a point light on this sphere, then every point on
the sphere would receive its normal illumination from the light, PLUS an
additional .5 from the ambient lighting.

This is one of the simplest concepts in POV-Ray, IMO. What part of it
*don't* you get?

-Xplo

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Matt Giwer wrote:
> 
>         I follow the rule of finish{ambient 0} and it looks very dark to dull.
> To make it look halfway like the original image I have to go the
> light_source as  rgb<1,1,1>*3 and *5 isn't that bad.

Try setting the sphere's diffuse to 1 (the default is .6, for some reason).

-Xplo

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In article <3A020F47.B09AA20D@hotmail.com>, Pabs <pab### [at] hotmailcom> 
wrote:

> Thats the Allman style
> try an even worse style - Whitesmiths
> or the tuxracer src for some v bad indentation
> personally I like the K&R style

It looks like an Allman/K&R mix, but it has a bunch of spaces where they 
shouldn't be, and some spots are missing spaces. But what I was really 
referring to was the sphere at the end.

I tend to use a modified K&R style for POV code, and Allman style with 
4-space indents for C/C++/ObjC. The K&R style lets me fit more POV 
objects and code into view, which makes it easier to edit the scene, but 
I find it easier to read C/C++/ObjC in Allman style.

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><

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"Chris Huff" <chr### [at] maccom> wrote in message
news:chrishuff-12F744.10000703112000@news.povray.org...
>
> > Thats the Allman style
> > try an even worse style - Whitesmiths
> > or the tuxracer src for some v bad indentation
> > personally I like the K&R style
>

Never had much time for the Altmans or Whitesnake myself, but R&B is cool.

BTW Shouldn't this be in O.T.?

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In article <3A0### [at] unforgettablecom>, 
inq### [at] unforgettablecom wrote:

> Try setting the sphere's diffuse to 1 (the default is .6, for some 
> reason).

The reason is that the ambient value is not 0 by default(I think the 
default for ambient is 0.2), and scenes often have multiple light 
sources. If it was 1 by default, everything would be washed out unless 
you set your own value.

-- 
Christopher James Huff
Personal: chr### [at] maccom, http://homepage.mac.com/chrishuff/
TAG: chr### [at] tagpovrayorg, http://tag.povray.org/

<><

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Xplo Eristotle wrote:
> 
> Matt Giwer wrote:
> >
> >         I follow the rule of finish{ambient 0} and it looks very dark to dull.
> > To make it look halfway like the original image I have to go the
> > light_source as  rgb<1,1,1>*3 and *5 isn't that bad.
> 
> Try setting the sphere's diffuse to 1 (the default is .6, for some reason).

	Increasing diffuse to 3 helps greatly. 

-- 
Wilkomorski is a frigging liar but holohuggers 
love him. 
	-- The Iron Webmaster, 173

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Matt Giwer wrote:
> 
> Xplo Eristotle wrote:
> >
> > Matt Giwer wrote:
> > >
> > >         I follow the rule of finish{ambient 0} and it looks very dark to dull.
> > > To make it look halfway like the original image I have to go the
> > > light_source as  rgb<1,1,1>*3 and *5 isn't that bad.
> >
> > Try setting the sphere's diffuse to 1 (the default is .6, for some reason).
> 
>         Increasing diffuse to 3 helps greatly.

An rgb 1 light that hits an rgb 1 surface with a diffuse of 1 and an
ambient of 0 should produce pure white. The fact that you need to
"overcharge" the lighting simulation suggests to me that you're using
light fading, shining the light through a partially transparent object
or absorbing media, or using a very dark image as a texture. I can see
from the code that the first two aren't the case, so I suspect it's the
third one.

-Xplo

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Xplo Eristotle wrote:

> If you were to shine a point light on this sphere, then every point on
> the sphere would receive its normal illumination from the light, PLUS an
> additional .5 from the ambient lighting.
> 
> This is one of the simplest concepts in POV-Ray, IMO. What part of it
> *don't* you get?

	Because when I have used it other times it has always appeared to work
as though it were simply reflecting more of the illumination so there
was never a reason to Read The Fine Docs. 

-- 
Live fast, love well, and have a glorious website.
<a href="http://www.giwersworld.org/mgiwer/">
The rest of Matt Giwer's World</a>
	-- The Iron Webmaster, 61

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Xplo Eristotle wrote:
> 
> Matt Giwer wrote:
> >
> > Xplo Eristotle wrote:
> > >
> > > Matt Giwer wrote:
> > > >
> > > >         I follow the rule of finish{ambient 0} and it looks very dark to dull.
> > > > To make it look halfway like the original image I have to go the
> > > > light_source as  rgb<1,1,1>*3 and *5 isn't that bad.
> > >
> > > Try setting the sphere's diffuse to 1 (the default is .6, for some reason).
> >
> >         Increasing diffuse to 3 helps greatly.
> 
> An rgb 1 light that hits an rgb 1 surface with a diffuse of 1 and an
> ambient of 0 should produce pure white. The fact that you need to
> "overcharge" the lighting simulation suggests to me that you're using
> light fading, shining the light through a partially transparent object
> or absorbing media, or using a very dark image as a texture. I can see
> from the code that the first two aren't the case, so I suspect it's the
> third one.

	In POV binaries I am posting the results of diffuse 1 2 and 3 in Sub:
pov.general ambient v diffuse

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