/* Marla Mayerson */
#include "rmannotes.sl"
displacement rectd(float freq = 9, Km = 0.05)
{
  
  float magnitude, layer_mag;
  
  float fuzz = 0.15;
  float left, right, top, bottom;
  float d;
  point center;
  float radius;
  
  float ss, tt;
 

  /* init */

  magnitude = 0;

  
  /* layer 1 - the rect */
  /* rotate 45 degrees and repeat pattern 'freq" times horz,vert */
  rotate2d(s, t, radians(45), .5, .5, ss, tt);
  
  ss = repeat(ss, 9);
  tt = repeat(tt, 9);

  left = 0.05; right = 0.75; /* rectangle sides */
  top = 0.1; bottom = 0.7; 
  layer_mag = pulse(left, right, fuzz, ss) * pulse(top, bottom, fuzz, tt);
  magnitude += layer_mag;

  /* layer 2 - disk */
  
  ss = repeat(s, 3);
  tt = repeat(t, 3);
  
  fuzz = 0.015;
  center = (0.5, 0.5, 0);  /* location of center of disk */
  radius = 0.25;           /* radius of disk */
  d = distance(center, (ss, tt, 0));
  layer_mag = 1 - smoothstep(radius - fuzz, radius + fuzz, d);
  magnitude += layer_mag;
  

  /* displace */
   
  P += -Km * magnitude * normalize(N);
  N = calculatenormal(P);

}