// Glass sculpture
// ---------------
// Entry for the 4th POV-Ray Short Code Contest

// Note: If you want to render faster, see the end of the file.

global_settings
{ photons { count 1e6 }

  // This macro is embedded here to save 1 character (at the end of the
  // last #end of the macro, where the last } of the global_settings can
  // be put immediately after the #end).
  // The parameters are the object color and the loop counter.
  #macro C(P, N)
    // This trick saves writing 'pigment' twice in the code, plus it
    // gives the plane the same reflection and phong as the spheres,
    // which is cool:
    pigment { rgbf P }
    finish { ior 1.5 reflection .3 phong 2} }

    #if(N)
      sphere
      { <sin(N) N/70-.6 cos(N)+5> .5
        photons { target refraction 1 }
        // Note that the sphere block is closed in the next iteration,
        // in which it also gets its pigment and finish.

        // Start the next iteration, calling the macro recursively,
        // changing the color to the one of the spheres:
        C(1 N-1)
    #end
  #end
} // global_settings end

merge
{ plane { y, -1 // The plane block will be closed in the macro
  C(<1, .7, .5> 70)
  rotate -x*9
}

light_source
{ 9, 1
  area_light z*2 y, 9, 5
  // Uncomment the following line for faster rendering:
  //adaptive 1
}