Any ideas on how I can get rid of or reduce the speckling in this 
isosurface?  It seems that the more convoluted the surface is the more 
speckled it gets.  I have tried playing with the intervals, samples, and 
max_gradient without much success.  Massive amounts of AA help a little 
but they don't remove the speckles, just blur them in.  Is there 
something that I am overlooking?

-- 
Skip

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On Wed, 14 Nov 2001 10:23:20 -0600, "Skip Talbot" <sta### [at] uiucedu> wrote:

> Any ideas on how I can get rid of or reduce the speckling in this isosurface?

Nice. Could you provide some source ? It seems you should start with eval
(described i.e. here http://www.povray.org/working-docs/id000167.html#6_5_4_5 ).

ABX
--
#declare _=function(a,b,x){((a^2)+(b^2))^.5-x}#default {pigment{color rgb 1}}
union{plane{y,-3}plane{-x,-3}finish{reflection 1 ambient 0}}isosurface{ //ABX
function{_(x-2,y,1)|_((x+y)*.7,z,.1)|_((x+y+2)*.7,z,.1)|_(x/2+y*.8+1.5,z,.1)}
contained_by{box{<0,-3,-.1>,<3,0,.1>}}translate z*15finish{ambient 1}}//POV35

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Did you try  to use "evaluate" in order to find out the proper
"max_gradient"? If not, take a look at the docs, specifically 6.5.4.
Although you increased it, the ammount might still be insuficient (the
largest number I've had to use in one of my isosurfaces was 248). If it's
not that, then I don't have a clue.

BTW, nice cloud. Do you intend to post the source?

Ruy

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Evaluate gave me a max_gradient of 24.556.  The speckles were unchanged at
this value.  As for the source... here's the cloud so far:

#declare F=function{pigment{
  spotted
  turbulence 5
  color_map { [0 rgb 0.6][1 rgb 0.0] }
  scale .125
  }
}

isosurface

        function { x^2 + 4*y^2 + z^2 -.25  +
(F(x*0.2,y*0.2,z*0.2).red-0.31)  }
        max_gradient 3
        contained_by{sphere{0,.75}}
pigment {rgbf 1 }
        interior {
        media {
                scattering {2, 5 extinction .5 }
                method 3
                intervals 1
      }
      }
   double_illuminate
   hollow
}



--
Skip

news:bq65vtkq78scf6d96s6n2bbofhhggapiph@4ax.com...
> On Wed, 14 Nov 2001 10:23:20 -0600, "Skip Talbot" <sta### [at] uiucedu>
wrote:
>
> > Any ideas on how I can get rid of or reduce the speckling in this
isosurface?
>
> Nice. Could you provide some source ? It seems you should start with eval
> (described i.e. here
http://www.povray.org/working-docs/id000167.html#6_5_4_5 ).
>
> ABX
> --
> #declare _=function(a,b,x){((a^2)+(b^2))^.5-x}#default {pigment{color rgb
1}}
> union{plane{y,-3}plane{-x,-3}finish{reflection 1 ambient
}}isosurface{ file://ABX
>
function{_(x-2,y,1)|_((x+y)*.7,z,.1)|_((x+y+2)*.7,z,.1)|_(x/2+y*.8+1.5,z,.1)
}
> contained_by{box{<0,-3,-.1>,<3,0,.1>}}translate z*15finish{ambient
1}}//POV35

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I tried a max_gradient of 2000 and got the same results.  A max_trace_level
of 10000 did not help either.  I'll post the cloud to p.t.s-f when its
completed.  I'm using it for my bomber scenes.

--
Skip
Ruy <ruy### [at] hipernetcombr> wrote in message news:3bf29dab@news.povray.org...
> Did you try  to use "evaluate" in order to find out the proper
> "max_gradient"? If not, take a look at the docs, specifically 6.5.4.
> Although you increased it, the ammount might still be insuficient (the
> largest number I've had to use in one of my isosurfaces was 248). If it's
> not that, then I don't have a clue.
>
> BTW, nice cloud. Do you intend to post the source?
>
> Ruy
>
>

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Try increasing max_trace_level.

-tgq

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I think I found it, try adjusting accuracy in the iso (default is 0.001,
0.0001 appeared ok)

-tgq

"Skip Talbot" <sta### [at] uiucedu> wrote in message
news:3bf2c8de$1@news.povray.org...
> I tried a max_gradient of 2000 and got the same results.  A
max_trace_level
> of 10000 did not help either.  I'll post the cloud to p.t.s-f when its
> completed.  I'm using it for my bomber scenes.
>
> --
> Skip
> Ruy <ruy### [at] hipernetcombr> wrote in message
news:3bf29dab@news.povray.org...
> > Did you try  to use "evaluate" in order to find out the proper
> > "max_gradient"? If not, take a look at the docs, specifically 6.5.4.
> > Although you increased it, the ammount might still be insuficient (the
> > largest number I've had to use in one of my isosurfaces was 248). If
it's
> > not that, then I don't have a clue.
> >
> > BTW, nice cloud. Do you intend to post the source?
> >
> > Ruy
> >
> >
>
>

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Yep, that did the trick!  Thanks for the suggestions everyone.

--
Skip
Trevor Quayle <Tin### [at] hotmailcom> wrote in message
news:3bf2cd85$1@news.povray.org...
> I think I found it, try adjusting accuracy in the iso (default is 0.001,
> 0.0001 appeared ok)
>
> -tgq
>
> "Skip Talbot" <sta### [at] uiucedu> wrote in message
> news:3bf2c8de$1@news.povray.org...
> > I tried a max_gradient of 2000 and got the same results.  A
> max_trace_level
> > of 10000 did not help either.  I'll post the cloud to p.t.s-f when its
> > completed.  I'm using it for my bomber scenes.
> >
> > --
> > Skip
> > Ruy <ruy### [at] hipernetcombr> wrote in message
> news:3bf29dab@news.povray.org...
> > > Did you try  to use "evaluate" in order to find out the proper
> > > "max_gradient"? If not, take a look at the docs, specifically 6.5.4.
> > > Although you increased it, the ammount might still be insuficient (the
> > > largest number I've had to use in one of my isosurfaces was 248). If
> it's
> > > not that, then I don't have a clue.
> > >
> > > BTW, nice cloud. Do you intend to post the source?
> > >
> > > Ruy
> > >
> > >
> >
> >
>
>

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It looks like a tissue on self-destruct :-)
Nice image.

-- 

//Mahalis
camera{location<0,0.25,-2> look_at 0.5*y} #declare 
T=texture{pigment{crackle scale 0.5 rotate 90 turbulence 0.75 
color_map{[0 rgb 1][0.05 rgb 1][0.1 rgb<1,0.25,1>][0.25 rgbf 1][1 rgbf 
1]}} finish{ambient 1}} #declare c=difference{torus{0.5,0.1 rotate 
-90*x}box{<0.7,0,0.2>,<-0.7,-0.7,-0.2>}}  merge{object{c 
translate<0.5,0.5,0>} object{c translate<-0.5,0.5,0>} 
cylinder{<1,0.5,0>,<1,0,0>,0.1} cylinder{<-1,0.5,0>,<-1,0,0>,0.1} 
cylinder{0.5*y,0,0.1} texture{T}}
--


  "Skip Talbot" <sta### [at] uiucedu> wrote in message 
news:3bf29a6b@news.povray.org...
  Any ideas on how I can get rid of or reduce the speckling in this 
isosurface?  It seems that the more convoluted the surface is the more 
speckled it gets.  I have tried playing with the intervals, samples, and 
max_gradient without much success.  Massive amounts of AA help a little 
but they don't remove the speckles, just blur them in.  Is there 
something that I am overlooking?

  -- 
  Skip

Post a reply to this message

Attachments:
Download 'iso-8859-1' (2 KB)

Here's an updated pic without the speckles

-- 
Skip
  Mahalis <don### [at] fakeycom> wrote in message 
news:3bf30a99$1@news.povray.org...
  It looks like a tissue on self-destruct :-)
  Nice image.

  -- 

  //Mahalis
  camera{location<0,0.25,-2> look_at 0.5*y} #declare 
T=texture{pigment{crackle scale 0.5 rotate 90 turbulence 0.75 
color_map{[0 rgb 1][0.05 rgb 1][0.1 rgb<1,0.25,1>][0.25 rgbf 1][1 rgbf 
1]}} finish{ambient 1}} #declare c=difference{torus{0.5,0.1 rotate 
-90*x}box{<0.7,0,0.2>,<-0.7,-0.7,-0.2>}}  merge{object{c 
translate<0.5,0.5,0>} object{c translate<-0.5,0.5,0>} 
cylinder{<1,0.5,0>,<1,0,0>,0.1} cylinder{<-1,0.5,0>,<-1,0,0>,0.1} 
cylinder{0.5*y,0,0.1} texture{T}}
  --


    "Skip Talbot" <sta### [at] uiucedu> wrote in message 
news:3bf29a6b@news.povray.org...
    Any ideas on how I can get rid of or reduce the speckling in this 
isosurface?  It seems that the more convoluted the surface is the more 
speckled it gets.  I have tried playing with the intervals, samples, and 
max_gradient without much success.  Massive amounts of AA help a little 
but they don't remove the speckles, just blur them in.  Is there 
something that I am overlooking?

    -- 
    Skip

Post a reply to this message

Attachments:
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