In article <cja### [at] netplexaussieorg>, 
cja### [at] earthlinknet says...
> In article <MPG.19835f5a3e611a0798983b@news.povray.org>,
>  Patrick Elliott <sha### [at] hotmailcom> wrote:
> 
> > I suspect that part of the problem was 
> > the sphere being way to small, but I also suspect that it is simply 
> > impossible to make media 'thick' enough to obscure objects at relatively 
> > short distances without resorting to something like what you seem to be 
> > talking about doing for the milk. However, I could have simply screwed up 
> > the settings. ;) I am pretty much flying blind here and experimenting 
> > with something I never used before. lol
> 
> To make it thicker, you just need to increase the density. To get the 
> same results at half the scale, you need to double the density. It 
> sounds like you think there is some limit to how dense you can make 
> media, or that high densities are somehow a "last resort".
> 
> 

Umm. I am confused here.. Looking at the docs implies that density is a 
color vector. I am a bit unclear how you make that more dense, nor does 
increasing the size of this vector seem to produce a noticeable effect. 
It is possible something about what I am doing is simply not allowing 
media to be seen, but... Like I said, I haven't a clue what I am doing, I 
just tried something and it doesn't seem to be doing what I expected (if 
anything). :p

camera {

 location <0.0000001,0,-200>
 look_at <0,0,0>
}

light_source {
     <0, 0, -130>
     color rgb <1, 1, 1>  // light's color
}

light_source {
     <130, 0, -130>
     color rgb <.5, .5, .5>  // light's color
}

light_source {
     <-130, 0, -130>
     color rgb <.5, .5, .5>  // light's color
}
 
difference {
  sphere {<0,0,0>, 100
    pigment {color rgb <1,0,0>}
    hollow
    interior {
      media {
        //absorption rgb <1,0,0>
        //emission rgb <1,0,0>
        intervals 1
        variance 0
        scattering {1, rgb <1,0,0> extinction 0}
        density {
          checker
          density {rgb <1,0,0>}
          density {rgb <1,1,0>}
        }
      }
    }
  }
  box {<-110,-110,5>,<0,110,-100>
    pigment {rgbt <1,1,1,1>}
  }
  rotate <0,-20,0>
  //no_shadow
}

-- 
void main () {

    call functional_code()
  else
    call crash_windows();
}

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In article <MPG.198496eefefa88b98983e@news.povray.org>,
 Patrick Elliott <sha### [at] hotmailcom> wrote:

> Umm. I am confused here.. Looking at the docs implies that density is a 
> color vector. I am a bit unclear how you make that more dense,

To put it in technical terms: use bigger numbers.


> nor does 
> increasing the size of this vector seem to produce a noticeable effect. 

It does.


>         scattering {1, rgb <1,0,0> extinction 0}

You only scatter red light, green and blue are unaffected by this media 
(though your pigment filters them out). When I'm doing an object that is 
mainly colored by its interior, I use a pigment of rgbf 1. Yours filters 
everything red. In addition, your extinction is set to 0, this media 
won't impede light passing through it. And you don't have anything else 
in your scene. I'm not really sure what effect you're after, you're 
certainly not going to get anything like milk with that. Your density 
pattern has so much fine detail that you are going to require a lot of 
sampling to get decent results, even after scaling it up by 10.

-- 
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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In article <cja### [at] netplexaussieorg>, 
cja### [at] earthlinknet says...
> In article <MPG.198496eefefa88b98983e@news.povray.org>,
>  Patrick Elliott <sha### [at] hotmailcom> wrote:
> 
> > Umm. I am confused here.. Looking at the docs implies that density is a 
> > color vector. I am a bit unclear how you make that more dense,
> 
> To put it in technical terms: use bigger numbers.
> 
> 
> > nor does 
> > increasing the size of this vector seem to produce a noticeable effect. 
> 
> It does.
> 
> 
> >         scattering {1, rgb <1,0,0> extinction 0}
> 
> You only scatter red light, green and blue are unaffected by this media 
> (though your pigment filters them out). When I'm doing an object that is 
> mainly colored by its interior, I use a pigment of rgbf 1. Yours filters 
> everything red. In addition, your extinction is set to 0, this media 
> won't impede light passing through it. And you don't have anything else 
> in your scene. I'm not really sure what effect you're after, you're 
> certainly not going to get anything like milk with that. Your density 
> pattern has so much fine detail that you are going to require a lot of 
> sampling to get decent results, even after scaling it up by 10.
> 
> 

Hmm.. Wasn't thinking about what was actually being scattered there. 
Probably why absorption didn't work either when I tried it that way. lol 
As for the effect.. I am not looking for milk, etc. Just really dense 
media. I used the checker pattern to add some variance to it when I 
realized something wasn't working and figured a pattern could tell me if 
it was working at all. The idea was to try to see if I could make the 
media solid enough to make it seem as though the inside was nearly solid, 
by having the media fill it in, instead of simply CSGing a box with the 
same color as the sphere. Stupid, but... lol Probably should have looked 
at some real examples first and worked from there. ;)

Basically, I wanted it so thick that the back shadow nearly disappears 
and the media seemed to be part of the sphere itself, not just something 
that kind of floated in it. At this point I am about ready to scrap the 
entire experiment, since I seem to flat out not get how this feature 
works. lol

-- 
void main () {

    call functional_code()
  else
    call crash_windows();
}

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