This is a quick example of how I would blend the two images for Earth,
but it needs a lot of tweaking, the maps dont' line up exactly and the
terminus of the shadow is too strict, right now there's too much
contrast.

Here is the snippet of relevant code:
#declare day = texture {
  pigment {image_map {png "earth-land.png" map_type 1 interpolate 2} }
  finish { diffuse 0.3 brilliance 0.1 ambient 0}
  rotate 90*y}

#declare night = texture {
  pigment {image_map {tga "earthnight.tga" map_type 1 interpolate 2} }
  finish { ambient 0.2 }
  rotate 90*y }

sphere { 0.0, 1
         texture {radial
                  texture_map { [0.0 day ]
                                [0.3 day ]
                                [0.6 night ]
                                [1.0 night ] }
                  rotate 0*y}
          }

--
Josh English -- Lexiphanic Lethomaniac
eng### [at] spiritonecom
The POV-Ray Cyclopedia http://www.spiritone.com/~english/cyclopedia/

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Attachments:
Download 'nightandday.jpg' (26 KB)

Preview of image 'nightandday.jpg'

Looks like some snow there in Baja California, I would have 
thought that it was always too hot for snow even at a high
altitude. 

-- 
Cheers
Steve              email mailto:ste### [at] zeroppsuklinuxnet

%HAV-A-NICEDAY Error not enough coffee  0 pps. 

web http://www.zeropps.uklinux.net/

or  http://start.at/zero-pps

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You might have to go with a sine_wave for the radial pattern instead or at
least blend at the start and end of the map as well as the middle.  Anyway, the
terminator (shadow line) region is awfully sharp in that.
I forget exactly how I did it but it also had a gradient masking texture for
the dark side so the daylight didn't have lights showing.  Wasn't a clean
attempt but it worked enough.

Bob

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What date is it in your scene ???

You know that only two times in the year the night/day-line goes
the way you showed ...
Most time it is not orthogonal to your current view ...
I think it would look quite nice, if you would make the
night/day-line not that sharp and rotate it about 5-10 degrees
around z...

But of course, well done

--

 ,',    Jan Walzer      \V/  http://wa.lzer.net     ,',
',','   student of      >|<  mailto:jan### [at] lzernet ',','
  '   ComputerScience   /A\  +49-177-7403863         '

Josh English <eng### [at] spiritonecom> schrieb in im Newsbeitrag:
3A283113.D206431A@spiritone.com...
> This is a quick example of how I would blend the two images for
Earth,
> but it needs a lot of tweaking, the maps dont' line up exactly
and the
> terminus of the shadow is too strict, right now there's too
much
> contrast.
>
> Here is the snippet of relevant code:
> #declare day = texture {
>   pigment {image_map {png "earth-land.png" map_type 1
interpolate 2} }
>   finish { diffuse 0.3 brilliance 0.1 ambient 0}
>   rotate 90*y}
>
> #declare night = texture {
>   pigment {image_map {tga "earthnight.tga" map_type 1
interpolate 2} }
>   finish { ambient 0.2 }
>   rotate 90*y }
>
> sphere { 0.0, 1
>          texture {radial
>                   texture_map { [0.0 day ]
>                                 [0.3 day ]
>                                 [0.6 night ]
>                                 [1.0 night ] }
>                   rotate 0*y}
>           }
>
> --
> Josh English -- Lexiphanic Lethomaniac
> eng### [at] spiritonecom
> The POV-Ray Cyclopedia
http://www.spiritone.com/~english/cyclopedia/
>
>


-----------------------------------------------------------------
---------------

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Quite probably. It's an image map that I got somewhere off of a NASA
server, I believe.

Josh

Steve wrote:

> Looks like some snow there in Baja California, I would have
> thought that it was always too hot for snow even at a high
> altitude.
>
> --
> Cheers
> Steve              email mailto:ste### [at] zeroppsuklinuxnet
>
> %HAV-A-NICEDAY Error not enough coffee  0 pps.
>
> web http://www.zeropps.uklinux.net/
>
> or  http://start.at/zero-pps
>
>   2:06am  up 52 days,  4:30,  2 users,  load average: 1.00, 1.00, 1.00

--
Josh English -- Lexiphanic Lethomaniac
eng### [at] spiritonecom
The POV-Ray Cyclopedia http://www.spiritone.com/~english/cyclopedia/

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Like I said, a rough skecth, I completely ignored axial tilt to make it
easier for me to see what was going on with the scene.

Josh

Jan Walzer wrote:

> What date is it in your scene ???
>
> You know that only two times in the year the night/day-line goes
> the way you showed ...
> Most time it is not orthogonal to your current view ...
> I think it would look quite nice, if you would make the
> night/day-line not that sharp and rotate it about 5-10 degrees
> around z...
>
> But of course, well done
>
> --
>
>  ,',    Jan Walzer      \V/  http://wa.lzer.net     ,',
> ',','   student of      >|<  mailto:jan### [at] lzernet ',','
>   '   ComputerScience   /A\  +49-177-7403863         '
>
> Josh English <eng### [at] spiritonecom> schrieb in im Newsbeitrag:
> 3A283113.D206431A@spiritone.com...
> > This is a quick example of how I would blend the two images for
> Earth,
> > but it needs a lot of tweaking, the maps dont' line up exactly
> and the
> > terminus of the shadow is too strict, right now there's too
> much
> > contrast.
> >
> > Here is the snippet of relevant code:
> > #declare day = texture {
> >   pigment {image_map {png "earth-land.png" map_type 1
> interpolate 2} }
> >   finish { diffuse 0.3 brilliance 0.1 ambient 0}
> >   rotate 90*y}
> >
> > #declare night = texture {
> >   pigment {image_map {tga "earthnight.tga" map_type 1
> interpolate 2} }
> >   finish { ambient 0.2 }
> >   rotate 90*y }
> >
> > sphere { 0.0, 1
> >          texture {radial
> >                   texture_map { [0.0 day ]
> >                                 [0.3 day ]
> >                                 [0.6 night ]
> >                                 [1.0 night ] }
> >                   rotate 0*y}
> >           }
> >
> > --
> > Josh English -- Lexiphanic Lethomaniac
> > eng### [at] spiritonecom
> > The POV-Ray Cyclopedia
> http://www.spiritone.com/~english/cyclopedia/
> >
> >
>
> -----------------------------------------------------------------
> ---------------

--
Josh English -- Lexiphanic Lethomaniac
eng### [at] spiritonecom
The POV-Ray Cyclopedia http://www.spiritone.com/~english/cyclopedia/

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Yep. I was just roughing in my method of how I would do it. Even this creates a bit
of darker shadow along the terminus. I know it needs a lot of work.

Josh

"Bob H." wrote:

> You might have to go with a sine_wave for the radial pattern instead or at
> least blend at the start and end of the map as well as the middle.  Anyway, the
> terminator (shadow line) region is awfully sharp in that.
> I forget exactly how I did it but it also had a gradient masking texture for
> the dark side so the daylight didn't have lights showing.  Wasn't a clean
> attempt but it worked enough.
>
> Bob

--
Josh English -- Lexiphanic Lethomaniac
eng### [at] spiritonecom
The POV-Ray Cyclopedia http://www.spiritone.com/~english/cyclopedia/

Post a reply to this message