//Set up the scene
//-------------------------------------------------------------//
#include "textures.inc"

camera {location <0,0,-2> look_at <0,-0.5,-0.0>}
light_source {<-5,2,-5> color rgb <1,1,1> spotlight } 
background {color rgb <0,0,0>}
              
plane {<0,1,0>, -2 pigment {checker rgb <0,0,0> }
    finish {reflection .3}}     
    

//-------------------------------------------------------------//

// declare the density file as a function
//-------------------------------------------------------------//
#declare F1= function {
        pigment {  
        density_file df3 "./goursat.df3"
                interpolate 1 
        }
}     
//-------------------------------------------------------------//

                
// draw the isosurface    
//-------------------------------------------------------------//    
isosurface {
   function {F1(x,y,z).grey }
 
   contained_by { box{<0.001,0.001,0.001>,<.999,.999,.999>  } } 
   threshold 0.18  
   //open
   accuracy 0.001
   max_gradient 50  
   scale 1.2
   pigment {rgb <1,0,0>}    
   finish { phong 0.8 }
   rotate <0,360*clock,0>
   translate <-.5,-1.,0>    
}   
//-------------------------------------------------------------//