// Exemplo de arquivo de descricao de cena para POV-ray
// Last edited on 2010-03-04 15:44:01 by stolfi

// ======================================================================
// CORES E TEXTURAS

background{ color rgb < 0.75, 0.80, 0.85 > }

#declare tx_plastico = 
  texture{
    pigment{ color rgb < 0.10, 0.80, 1.00 > }
    finish{ diffuse 0.8 ambient 0.1 specular 0.5 roughness 0.005 }
  }

#declare tx_fosca = 
  texture{
    pigment{ color rgb < 1.00, 0.80, 0.10 > }
    finish{ diffuse 0.9 ambient 0.1 }
  }

#declare tx_espelho = 
  texture{
    pigment{ color rgb < 0.3, 0.3, 1.00 > }
    finish{ diffuse 0.2 reflection 0.7*< 1.00, 0.85, 0.30 > ambient 0.1 }
  }

#declare tx_vidro = 
  texture{
    pigment{ color rgb < 0.85, 0.95, 1.00 > filter 0.70 }
    finish{ diffuse 0.03 reflection 0.25 ambient 0.02 specular 0.25 roughness 0.005 }
  }


#declare tx_xadrez =
  texture{
    pigment{ checker color rgb < 0.10, 0.32, 0.60 >, color rgb < 1.00, 0.97, 0.90 > }
    finish{ diffuse 0.9 ambient 0.1 }
    scale 2.0
  }

#include "eixos.inc"

//Programa

#declare chao = 
  box{ <-20,-20,-1>, <+20,+20,0> }

#macro interpola(f0,v0,f1,v1,f)
  #local ss = (f-f0)/(f1-f0);
  #local rr = 1-ss;
  (rr*v0+ss*v1)
#end

#macro interpola_complicado (t0, v0, v1, v2, v3, t3, tt)
  //Fase 1
  #local v01 = interpola(t0,v0,t3,v1,tt);
  #local v12 = interpola(t0,v1,t3,v2,tt);
  #local v23 = interpola(t0,v2,t3,v3,tt);
  //Fase 2
  #local v012 = interpola(t0,v01,t3,v12,tt);
  #local v123 = interpola(t0,v12,t3,v23,tt);
  //Fase 3
  interpola(t0,v012,t3,v123,tt);
#end

#macro grafico(x0, y0, y1, y2, y3, x3, N)
  #local intervaloX = (x3-x0)/N;
  #local X=x0; 
  #while(X<=x3)
    #local Y = interpola_complicado(x0, y0, y1, y2, y3, x3, X);
    #local X = X + intervaloX;
    object{sphere {<0,X,Y> 0.1} texture{tx_espelho}}
  #end
#end

#macro grafico4(x0, y_inicial, y10, y11, y20, y21, y30, y31, y40, y41, y_final, x3, N)

  #local y_inicial1 = (y11+y20)/2; 
  #local y_inicial2 = (y21+y30)/2;
  #local y_inicial3 = (y31+y40)/2;
 
  grafico(x0,y_inicial,y10,y11,y_inicial1,x3/4,N)
  grafico(x3/4,y_inicial1,y20,y21,y_inicial2,x3/2,N)
  grafico(x3/2,y_inicial2,y30,y31,y_inicial3,3*x3/4,N)
  grafico(3*x3/4,y_inicial3,y40,y41,y_final,x3,N)

#end

grafico4(-4, 0, -2, 2, 4, 6, -1, 3, -4, 1, 2, 10, 30)

//object{ chao  translate < 0,0,-5 > texture{ tx_xadrez } }

object{ eixos(3.00) }

#include "camlight.inc"
#declare centro_cena = < 0.00, 0.00, 0.00 >;
#declare raio_cena = 17.0;
#declare dir_camera = < 1.00, 0.00, 0.00 >;
#declare dist_camera = 6.0;
#declare intens_luz = 1.00;
camlight(centro_cena, raio_cena, dir_camera, dist_camera , z, intens_luz)