// 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 < 1.0, 1.0, 1.0 > }

#declare tx_plastico = 
  texture{
    pigment{ color rgb < 0.20, 0.70, 0.10 > }
    finish{ diffuse 0.8 ambient 0.1 specular 5.8 roughness 0.1 }
  }

#declare tx_vidro = 
  texture{
    pigment{ color rgb < 0.1, 0.95, 0.20 > filter 0.85 }
    finish{ diffuse 0.03 reflection 0.25 ambient 0.02 specular 0.25 roughness 0.1 }
  }

#declare tx_xadrez =
  texture{
    pigment{ checker color rgb < 0.10, 0.42, 0.60 >, color rgb < 1.00, 0.97, 0.90 > }
    finish{ diffuse 0.9 ambient 0.1 }
    scale 1.0
  }


// ======================================================================
// DESCRIÇÃO DA CENA 


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

#macro interpola4(ti, v0, v1, v2, v3, tf, tt)
	#local v01 = interpola(ti, v0, tf, v1, tt);
	#local v12 = interpola(ti, v1, tf, v2, tt);
	#local v23 = interpola(ti, v2, tf, v3, tt);
	#local v012 = interpola(ti, v01, tf, v12, tt);
	#local v123 = interpola(ti, v12, tf, v23, tt);
  interpola(ti, v012, tf, v123, tt);
	
#end

#macro grafico(x0, y0, y1, y2, y3, x3, N)
	#local delta = (x3 - x0)/N;
	#local i = 0;
	#local xx = x0;
	
	#while(i < N)
		#local yy = interpola4(x0, y0, y1, y2, y3, x3, xx);
		
		object{ 
				sphere { <xx, yy, 0> , 0.1 } 
		}
		#local i = i + 1;
		#local xx = xx + delta; 
	#end

#end 

#macro grafico4(x0, y01, y02, y03, y12, y13, y22, y23, y32, y33, y34, x3, N)
	#local xx = x0;
	#local delta = (x3 - x0)/4;

	grafico(x0, y01, y02, y03, (y02 + y12)/2, xx+delta, N)
	#local xx = xx + delta;	
	
	grafico(xx, (y02 + y12)/2, y12, y13, (y13 + y22)/2, xx+delta, N)
	#local xx = xx + delta;	

	grafico(xx, (y13 + y22)/2 , y22, y23, (y23 + y32)/2, xx+delta, N)
	#local xx = xx + delta;	

	grafico(xx, (y23 + y32)/2, y32, y33, y34, xx+delta, N)
	    
#end

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

#include "eixos.inc"

// Aqui está a cena, finalmente:

union{
  object{ eixos(3.00) }
	//object{ chao  translate < 0,0,-4 > texture{ tx_xadrez } }
	grafico4(0, 1, 2, 3, 6, 7, -6, -7, 3, 2, -4, 5, 200)
		
}

#include "camlight.inc"
#declare centro_cena = < 0.00, 1.60, 1.00 >;
#declare raio_cena = 10.0;
#declare dir_camera = < 0.01, -1.01, 10.00 >;
#declare dist_camera = 16.0;
#declare intens_luz = 1.00;
camlight(centro_cena, raio_cena, dir_camera, dist_camera , z, intens_luz)