I have been trying to mimic an experiment where there are two boxes with
different indices of refraction one on top of the other.  I am still getting
weird artifacts in the rendering.  I have posted this problem here before and
got some advice and it looks better, but there are still problems.  I have also
posted an image on the binaries.images section to illustrate the problem.  The
bottom region should be clear and the top liquid should be a translucent
yellow.  At the top of the upper region there seems to be a weird line.  Also,
there are weird triangles formed.  I do not think these are all real.  I have
overlapped the two regions a tiny bit and used the merge operator (this seems
to work the best).  I did try separating the two regions a tiny bit instead of
the merge operator, but it still has these artifacts and I would prefer not to
do that since the real experiment does not have a flat interface, as this ideal
case does, and it seems there are other issues with a tiny separation.  I also
have the bottom region intersecting a plane (the floor) at the bottom to make
things look better (as from previous advice from this forum).  I have turned
diffuse and roughness to zero to try to mimic real life (they are supposed to
be liquids), but playing with them did not seem to fix the artifacts anyway.

Any Ideas,
Mike

Here is the code:
#include "colors.inc"
#include "textures.inc"

global_settings{max_trace_level 255}
camera {
     location  <0, 3, 260>
    look_at   <0, 3, 0>
    angle 2.5
      rotate <-30*1,-30*1,0>
   }
#declare MaterialAlcohol =
material {
  texture {
     pigment {
        color rgbf<1, 1, 1,1>
      }
 finish {
        ambient 0.0
        diffuse 0
         reflection {
          0.0, 1.0
          fresnel on
        }
        conserve_energy
        specular  0
        roughness 0
 }
  }
  }
    #declare HeavyLiquid =
material {
  texture {
     pigment {
        color rgbf<0.6, 0.5, 0,1>
      }
 finish {
        ambient 0.0
        diffuse 0
         reflection {
          0.0, 1.0
          fresnel on
        }
      conserve_energy
       specular 0
     roughness 0
 }
  }
  }
#declare AlcoholRegion=
box { <-1.899, -0.2, -1.899>, <1.899, 3, 1.899>
material { MaterialAlcohol }
  interior {
  ior 1.3800
}
 }
#declare HeavyLiquidRegion=
box { <-1.899, 2.99, -1.899>, <1.899, 5, 1.899>
material { HeavyLiquid }
 interior {
    ior 1.55
}
}
merge{
object{AlcoholRegion}
object{HeavyLiquidRegion}
}
light_source {
    <4, 8, 10>
    color White
  }
plane{y,0 texture{pigment{White}finish{ambient 0 diffuse 1}}}

Post a reply to this message