// Exemplo de arquivo de descricao de cena para POV-ray
// Last edited on 2021-12-09 08:17:39 by stolfi

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

background{ color rgb 0.5*< 0.2, 0.4, 1.0 > }

#declare tx_dirt =
  texture{
    pigment{ color rgb < 0.2, 0.2, 0.2 > }
    finish{ diffuse 0.8 reflection 0.25 ambient 0.1 specular 0.5 roughness 0.1}
  }
#declare tx_trunk =
  texture{
    pigment{ color rgb < 0.7, 0.4, 0.2 > }
    finish{ diffuse 0.8 reflection 0.25 ambient 0.1 specular 0.5 roughness 0.1}
  }
#declare tx_leaf =
  texture{
    pigment{ color rgb < 0.2, 1, 0.2 > }
    finish{ diffuse 0.8 reflection 0.25 ambient 0.1 specular 0.5 roughness 0.1}
  }


#declare tx_ground =
  texture{
    pigment{ color rgb < 0.3, 1.0, 0.2 > }
    finish{ diffuse 0.8 specular 0.5 roughness 0.1}
  }

// ======================================================================
// DESCRICAO DA CENA 

#declare roleta = seed(10);

#declare tree_lvls = 10;

#declare leaf = disc {
    <0, 0, 0>, <0, 1, 0> ,1 
    texture{ tx_leaf}
  }
#declare ground = 
  box{ 
    <-400,-400,-1>, <+400,+400,0> 
    texture{ tx_ground }
  }


#macro spawn_branch(length, thick, base_x, base_y, base_z, branch_lvl)
  #if (branch_lvl >= tree_lvls)
    // rotations
    #local x_rot = rand(roleta);
    #local y_rot = rand(roleta);
    #local z_rot = rand(roleta);

    // spawn leaf
    object{leaf  translate<base_x,base_y,base_z> rotate<x_rot,y_rot,z_rot>}
  #else
    #local sub_brach_lvl = branch_lvl - 1;
    // spawn branches
    #local sub_branch_length = (2*length)/3;
    #local sub_branch_thick = (2*thick)/3;
    #local sub_branch_x = base_x;
    #local sub_branch_y = base_y;
    #local sub_branch_z = base_z + length;
    #local sub_branch_lvl = branch_lvl + 1;

    // rotations
    #local x_rot = rand(roleta)*45;
    #local y_rot = rand(roleta)*45;
    #local z_rot = rand(roleta)*45;
    object{
      union{
        difference {
          object{
            sphere{
              <base_x, base_y, base_z>, thick * 1.5
              texture{ tx_trunk }
            }
          }
          object{
            cone {
              <base_x, base_y, base_z>, thick * 1.5    // Center and radius of one end
              <base_x, base_y, base_z+ length/5>, thick   // Center and radius of other end
              texture { tx_trunk}
            }
          }
        }
        object{
          cone {
            <base_x, base_y, base_z>, thick * 1.5    // Center and radius of one end
            <base_x, base_y, base_z+ length/5>, thick   // Center and radius of other end
            texture { tx_trunk}
          }
        }
        object{
          cylinder {
            <base_x, base_y, base_z+ length/5>,
            <base_x, base_y, base_z+ length>,
            thick
            texture { tx_trunk}
          }
        }
      }
      rotate <x_rot,y_rot,z_rot>
    }
    spawn_branch(sub_branch_length, sub_branch_thick, sub_branch_x, sub_branch_y, sub_branch_z, sub_branch_lvl)
    spawn_branch(sub_branch_length, sub_branch_thick, sub_branch_x, sub_branch_y, sub_branch_z, sub_branch_lvl)
  #end
#end

#include "eixos.inc"
// object{ eixos(10) }

// Aqui est� a cena, finalmente:

union{
  object{ground}
  spawn_branch(10, 1, 0, 0, 0, 0)
}

#include "camlight.inc"
#declare centro_cena = < 0.00, 0.00, 15.00 >;
#declare raio_cena = 35;
#declare dir_camera = < 20.00, 7.00, 2.00 >;
#declare dist_camera = 5*raio_cena;
#declare intens_luz = 1;
camlight(centro_cena, raio_cena, dir_camera, dist_camera , z, intens_luz)