/*
S:=(x^2+y^2+z^2-a^2-b^2)^2-4*(a^2-x^2)*(b^2-y^2) ; quartique dome de Bohème
1,1 -------- S := (x^2+y^2+z^2-2)^2-4*(1-x^2)*(1-y^2)
<1,0,0,0,-2,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,2,0,0,0,0,0,0,1,0,-4,0,0.>

1.5,1 -------- S :=(x^2+y^2+z^2-3.25)^2-4*(2.25-x^2)*(1-y^2)
<1,0,0,0,-2,0,0,2,0,-2.50,0,0,0,0,0,0,0,0,0,0,1,0,0,2,0,2.50,0,0,0,0,1,0,-6.50,0,1.5625>

*/
#include "colors.inc"
#include "metals.inc" 
    
camera  { orthographic location <0,2,-4> look_at<0,0.45,0> angle 82} //  
light_source { <-10,20,-20> color rgb<0.8,0.8,1>  shadowless } 
light_source { <10,20,-20> color White  shadowless} 
light_source { <4,-20,-15> color Red*0.7  shadowless}
  
background{White}  
//plane {z, 6  pigment{ SkyBlue*1.2}}
// ----------------------------------------  
#macro crosscap(textu)
union {  
    poly{4, <1,0,0,0,-2,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,2,0,0,0,0,0,0,1,0,-4,0,0.>
      texture{     
              textu
              normal {
              granite 1
              turbulence 0.5
              scale 0.1
              accuracy 0.5
                     } 
             }   
      finish {ambient 0.55 diffuse 0.35 reflection 0.1 roughness 0.001} 
         }
           
    }           
#end    
// ----------------------------------------
object{ crosscap(T_Silver_3C)
        scale 1.3    // scale 1.3 pour a=b=1 -- scale 1 pour a=1.5 b=1
        rotate <0,90,0> 
        rotate <-90,0,0> 
        
        } 
object{ crosscap(T_Gold_5E)
        scale 0.45
        rotate <0,90,90> 
        translate <-2.4,2.2,0>
}
object{ crosscap(T_Gold_5E)
        scale 0.45
        rotate <80,20,-0> 
        translate <2.4,2.2,0>
}
    
text {	ttf "times.ttf" "AE"
        0.3,0                                                 
        pigment { Blue}
        scale 0.2
        rotate 40*x
        translate <+3,-2.1,0> 
        finish{ ambient 0.2 diffuse 0.3} }