Hello All

I am currently working on a project to render skies using physically
accurate or t least approximate colours and intensities. I have been advised
to use POV-Ray simply because it is a very good ray tracing program. My
knowledge of the language is very bad and I am struggling to use it.
I have gathered all the equations to implement my model, but I am completely
clueless as to how POV-Ray works. I would be very greatful if anyone could
provide with a skeleton program that would setup the scene for me. That is,
create the earth and sky spheres and postion the view on the surface of the
earth looking at the sky.

Then I can use that to change the colour of the sky based on equation I
have.

I would like to apologise for this, but my POV-Ray knowledge is very bad and
I am starting to panic !!!

Any help would be greatly appreciated.

Please feel free to reply to me on the email address listed below.

Thanks..

Ammar

a.a### [at] ueaacuk

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It's a pretty simple to do, but it also depends on how your model is set up.
Does the camera need to be on the surface of a real sphere? or will a plane do?
(Unless you're going for extreme panoramas from high altitudes, a plane would
work.) Another thing to consider is this: do you need the sun placed accurately
or not? Perhaps if you could give us some clues as to what your process needs in
more detail we can provide a clear answer

By the way, someone has been working on an accurate model of the solar system,
so you could probably use those figures to create the planets, but you'll have
to ask Uncle Ken where it is, because I've lost that link.

Josh
Ammar wrote:

> Hello All
>
> I am currently working on a project to render skies using physically
> accurate or t least approximate colours and intensities. I have been advised
> to use POV-Ray simply because it is a very good ray tracing program. My
> knowledge of the language is very bad and I am struggling to use it.
> I have gathered all the equations to implement my model, but I am completely
> clueless as to how POV-Ray works. I would be very greatful if anyone could
> provide with a skeleton program that would setup the scene for me. That is,
> create the earth and sky spheres and postion the view on the surface of the
> earth looking at the sky.
>
> Then I can use that to change the colour of the sky based on equation I
> have.
>
> I would like to apologise for this, but my POV-Ray knowledge is very bad and
> I am starting to panic !!!
>
> Any help would be greatly appreciated.
>
> Please feel free to reply to me on the email address listed below.
>
> Thanks..
>
> Ammar
>
> a.a### [at] ueaacuk

--
Josh English
eng### [at] spiritonecom
"May your hopes, dreams, and plans not be destroyed by a few zeros."

Post a reply to this message

Ammar <a.a### [at] ueaacuk> wrote ...
> Hello All
>
> I am currently working on a project to render skies using physically
> accurate or t least approximate colours and intensities. I have been
advised
> to use POV-Ray simply because it is a very good ray tracing program. My
> knowledge of the language is very bad and I am struggling to use it.
> I have gathered all the equations to implement my model, but I am
completely
> clueless as to how POV-Ray works. I would be very greatful if anyone could
> provide with a skeleton program that would setup the scene for me. That
is,
> create the earth and sky spheres and postion the view on the surface of
the
> earth looking at the sky.
>
> Then I can use that to change the colour of the sky based on equation I
> have.
>
> I would like to apologise for this, but my POV-Ray knowledge is very bad
and
> I am starting to panic !!!

For the most physically realistic output, you should use a sky sphere that
contains scattering media.  You would want to use a media that scatters
mostly blue light (as the earth's atmosphere does).  This has been done in
the past and it has produced very realistic skies.  Check out the message
titled '"Rust and Sky" source" in povray.text.scene-files for some code that
creates an atmosphere using scattering media.  You can modify the scattering
properties to produce different looking skies.  This technique will even
produce sunset colors if used properly.

-Nathan

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Ammar,

I was unable to reply to the email message that you sent me.  My reply was
returned undelivered.  Please look in the newsgroup
"povray.text.scene-files" on this server for the message entitled ""Rust and
Sky" source".  The author of the original message is "Xplo Eristotle" and
the message is dated April 2, 2000.  The source code for the scattering
media sky is located in the body of the message.

-Nathan Kopp

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