POV Ray 3.7 code
//====================================================
// Sequential Newton's method set mountain landscape
// generation (POV-Ray 3.7 small spheres)
//===================================================

#include "colors.inc"    // Standard Color definitions
#include "glass.inc"    // Glass pigments
#include "metals.inc"  // Metal pigments

global_settings {assumed_gamma 1.0}     // set display gamma
#declare Th =  -60;    // set rotation angles
#declare Ph = 0;

background { color red 0.2 green 0.6 blue 0.8 }
plane { < 0.0, 10, 0.0 >, 1    //  normal vector to palne | -1 is the height of the floor
   pigment { color .3*Green }
   normal { bumps 0.5 scale 0.6}  // grass effect
   rotate < 0, Th, Ph >}

 camera {{							// set view point (camera) location
    location < 0, 120, -180>
    look_at  < 0, -20, 0>
    angle 90}

light_source   // create a regular point light source
{
  0*x // light's position (translated below)
  color Gold // light's color
  translate <1000, 1000, -100>
}

light_source    // Area light source (creates soft shadows)
{
  0*x // light's position (translated below)
  color Silver  // light's color
  // <widthVector> <heightVector> nLightsWide mLightsHigh
  area_light
  <8, 0, 0> <0, 0, 8> // lights spread out across this distance (x * z)
  4, 4                // total number of lights in grid (4x*4z = 16 lights)
  adaptive 0          // 0,1,2,3...
  jitter              // adds random softening of light
  translate <40, 80, -40>   // <x y z> position of light
}

 #declare R = 0.9;   // set radius value
 #declare L = 1.0;   // set square area side
 #declare X = 0.01;  // set co-ordinate x initial value
 #declare Y = 0.01;  // set co-ordinate y initial value
 #declare Cx = 0.0;   // set x shift
 #declare Cy = 0.0;   // set y shtift
 #declare n = 200;  // set number of pixels per area side
 #declare N = 20;   // set number of cycles

//  replace -n, n by -n*clock, n*clock for animation
#for (p, -n, n/4, 1)  // partial values -n/4, 0,  n/4
     #declare IncX = p*L/n;
   #for (q, -n, n, 1)
       #declare IncY = q*L/n;
       #declare X = IncX;
       #declare Y = IncY;
       #for (k,0,N)
       #declare XX = 3*X/4 - X*(X*X - 3*Y*Y)/((X*X + Y*Y)*(X*X + Y*Y)*
       (X*X + Y*Y)*4);
       #declare YY = 3*Y/4 - Y*(Y*Y - 3*X*X)/((X*X + Y*Y)*(X*X + Y*Y)*
       (X*X + Y*Y)*4);
       #declare X = XX;
       #declare Y = YY;

       #if ((X - Cx)*(X-Cx) + (Y - Cy)*(Y - Cy) < R)
     sphere {
       < p, k, q >, 1
          hollow
      radiosity { importance 1.0 }
          texture {
          pigment { color rgb < abs(sin(.5*pi*k/N)), 0.3,
          abs(cos(pi*(k/N))) > }
                      }
          finish { ambient rgb <0.3,0.1,0.2>
            diffuse .3
            reflection .3
            specular 1
           }

rotate < 0, Th, Ph >
translate < 0, 0, 0 >  }

#end  // end if
#end  // end for k
#end  // end for q
#end  // end for p