//Tp06 by Carlos Robson
// ======================================================================

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

#declare Yellow = rgb<255, 255, 0>;
#declare Black =  rgb < 0.4, 0.4, 0.4 >;

#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 esfera =
	sphere {
		< 0, 0,  0>, 0.25 // Near lower left corner
		 texture{ tx_plastico }
	}
	
  
// ======================================================================
// DESCRIÇÃO DA CENA 

#include "eixos.inc"

object{ eixos(3.00) }

//matriz com os pontos P
#declare P = array[4][4];
//Arco 1
#declare P[0][0] = <0,0,0>;
#declare P[0][1] = <0,1,-2>;
#declare P[0][2] = <0,3,-2>;
#declare P[0][3] = <0,4,0>;

//Arco 2
#declare P[1][0] = <0,4,0>;
#declare P[1][1] = <0,4,2>; 
#declare P[1][2] = <1,0,2>;
#declare P[1][3] = <1,0,4>;

//Arco 3
#declare P[2][0] = <1,0,4>;
#declare P[2][1] = <0,1,6>; 
#declare P[2][2] = <0,3,6>;
#declare P[2][3] = <-1,4,4>;

//Arco 4
#declare P[3][0] = <-1,4,4>;
#declare P[3][1] = <-1,0,2>; 
#declare P[3][2] = <0,4,2>;
#declare P[3][3] = <0,0,0>;

//matriz com os pontos Q
#declare Q = array[4][4];
//Arco 1
#declare Q[0][0] = <0,0,0>;
#declare Q[0][1] = <0,1,-2>;
#declare Q[0][2] = <0,3,-2>;
#declare Q[0][3] = <0,0,0>;

//Arco 2
#declare Q[1][0] = <0,0,0>;
#declare Q[1][1] = <0,-1,2>; 
#declare Q[1][2] = <0,-3,2>;
#declare Q[1][3] = <0,0,0>;

//Arco 3
#declare Q[2][0] = <0,0,0>;
#declare Q[2][1] = <0,2,4>; 
#declare Q[2][2] = <0,3,6>;
#declare Q[2][3] = <0,0,0>;

//Arco 4
#declare Q[3][0] = <0,0,0>;
#declare Q[3][1] = <0,-2,-4>; 
#declare Q[3][2] = <0,-3,-6>;
#declare Q[3][3] = <0,0,0>;

#declare R = array[4][4];
#for(i, 0, 3, 1)
	#for(j, 0, 3, 1)
		#declare R[i][j] = <0,0,0>;
	#end
#end

#macro interpola(to, vo, t1, v1, tt )
	#local r = (tt-to)/(t1-to);
	#local s = 1-r;
	#local vv= s*vo+r*v1;
	vv
#end

#macro arcobezier(to, t1, a, b, c, d, tt )
	#local ab = interpola(to, a, t1, b, tt );
	#local bc = interpola(to, b, t1, c, tt );
	#local cd = interpola(to, c, t1, d, tt );
	#local abc = interpola(to, ab, t1, bc, tt );
	#local bcd = interpola(to, bc, t1, cd, tt );
	#local abcd = interpola(to, abc, t1, bcd, tt );
	abcd
#end
 // N = num de lados, 
#macro interpolamatriz(PO, QO, N, CO, CI, cc, R)
	#local i = 0;
	#while(i < N)
		#local k = 0;
		#while(k<3)
			#declare R[i][k] = interpola(CO,PO[i][k], CI, QO[i][k], cc );
			#local  k = k+1;
		#end
			#local i = i+1;
	#end
#end
#macro inmatrizes(P, Q, N)
	#for(cc, 0, 1, 0.2)
		interpolamatriz(P, Q, N, 0, 1, cc, R )
		object{noh(R, N, 20)}
	#end
#end

#macro arco(a0, a1, a2, a3, t0, t1, n)
	union{
	#declare passo = 1/n;
	#declare j = t0;
	#while (j <= t1)
		object { esfera translate arcobezier(t0,t1, a0, a1, a2, a3, j)}
		#declare j=j+passo;
	#end
	}
#end

//Po = matrix, n = num de arcos, m = num de bolas por arco
#macro noh(Po, n, m)
		union{
			#declare lado = m/n;
			#local i = 0;
			#while(i < n)
				object {arco (Po[i][0], Po[i][1], Po[i][2], Po[i][3], i*lado, (i+1)*lado, m) }
			#local i = i+1;
			#end
		}
#end

//Suaviza 2 junções
#macro suaviza(Po, i)
	#local j =  mod(i+1, 4);
	#local vv = (Po[j][1]-Po[i][2])/2;
	#declare Po[i][2]= Po[i][3]-vv;
	#declare Po[j][1]= Po[j][0]+vv;
#end

//Po= matriz, n numero de arcos
#macro suavizamatriz(Po, n)
	#local i = 0;
		#while(i < n )
			suaviza(Po, i)
			#local i = i+1;
		#end
#end
suavizamatriz(P, 4)
//object{noh(P, 4, 20)}
//bject{noh(Q, 4, 20)}
inmatrizes(P, Q, 4)


#include "camlight.inc"
#declare centro_cena = < 0.00, 0.00, 1.00 >;
#declare raio_cena = 7.0;
#declare dir_camera = < 14.00, 7.00, 4.00 >;
#declare dist_camera = 5*raio_cena;
#declare intens_luz = 1.20;
camlight(centro_cena, raio_cena, dir_camera, dist_camera , z, intens_luz)