"Mike" <win### [at] hotmailcom> wrote:
> I have been trying to get a section basically a cube where the top and bottom
> surfaces are an egg crate pattern.  The inner material is a liquid with a high
> ior.  I managed to get the pattern to work with isosurfaces getting help
> already from this forum.  It seems that black dots are appearing though.
> Actually, I notice that if I lower the refractive index of my material the
> black dots go away, so it definitely is a total internal reflection thing.  I
> guess the light reflects back and forth so many times it either blows out the
> max_trace_level or the adc_bailout. It seems that by turning off adc_bailout
> (seting equal to 0 ) and messing with the max_trace_level I can make less black
> dots appear, but only if I turn adc_bailout off. However, I have yet to be
> able to make max_trace_level equal to 255 with adc_bailout off because it takes
> too long to render.  Maybe I do not fully understand how adc_bailout works, it
> seems if I make it really small I get no change from if I have it not there at
> all (the default value).  Any ideas?

As I said in my previous post, try HF instead:

This produces an object similar to what you have, I didn't play with the numbers
too much to try to get exact.

This renders fairly quickly and you can bump the max_trace up if you want.

There are still some black dots.  This is a result of the reflection/refraction
of the material.  A lot of it is actually reflection of the background which is
black by default (try putting background{rgb 1} in to see the difference.  Some
of this will get minimized with AA, but it can never disappear completely.

-tgq


//START
#declare f_1= function (x,y){( 0.8-0.2*sin(3*6.2832*x)*sin(3*6.2832*y))}

#declare RES=500;
#local HF1=
  height_field{
    function RES,RES {pattern{ function {
      f_1 ((x-1/2)*1.9*2,(y-1/2)*1.9*2)
    }
   }
  }
  smooth
  translate <-1/2,0,-1/2>
  scale <2.01,1,2.01>
}

#declare Mixingregion2=
intersection{
  object{HF1}
  //object{HF1 rotate 180*z}
  box{-1,1}
  scale <1.9,0.6,1.9>
  translate 3*y
  material {MixedRegion}
}
//END

Post a reply to this message