// Exercicio 2
// Last edited on 2001-06-09 20:40:14 by stolfi

#include "colors.inc"

background{ color rgb < 0.00, 0.53, 0.75 > }

light_source {
  < 40.00, 100.00, 20.00 >
  color rgb < 1.00, 1.00, 1.00 >
} 

camera {
  location  < 6.00, 12.00, 0.50 >
  right     < -0.80, 0.00, 0.00 >
  up        <  0.00, 0.00, 0.60 >
  sky       <  0.00, 0.00, 1.00 >
  look_at   <  0.00, 0.00, 1.50 >
} 

#declare detalhe =
    torus { 0.3, 0.05        // major and minor radius
    rotate 90*x      // so we can see it from the top
    pigment { color rgb < 0.10, 0.80, 1.00 > }
}

#declare estrela =
  union {
  object {detalhe translate <0,0,0>}
  object {detalhe rotate 90*x translate <0,0,0>}
  object {detalhe rotate 150*x translate <0,0,0>}
  object {detalhe rotate -150*x translate <0,0,0>}
}

#declare pilar =
   cylinder {
    <0, 0, 0>,
    <0, 0, 2.5 >,
    0.2
}

#declare ruina =
   blob {
   threshold 0.5 
   #declare i = 3.5;
   #declare j = 0;
   #declare tonalidade = 1;
   #while ((i > 1) & (j < 1.6))
     #if(i>2)
        #declare tonalidade = 1;
     #else
        #declare tonalidade = 5;
     #end
     sphere { <0,0,0>, i , 1 scale <0,0,0.2>translate<0,0,j>pigment{Blue*i/tonalidade } }                               
      #declare i = i-0.5;                    
      #declare j = j +0.3;             
     #end        
     finish {phong 1 } }     

object {ruina translate <0,0,0>} 
object {estrela translate <0,0,1.9>}
#declare i = -3; #while ( i < 4 )    
   object {pilar translate <3,i,0>pigment{Gray}}    
   object {pilar translate <4,i,0> pigment{Gray}}
   object {pilar translate <-3,i,0> pigment{Gray}}
   object {pilar translate <-4,i,0> pigment{Gray}}
   #declare i  = i + 1;
#end