#include "rmannotes.sl"


displacement cavity_d (float freq=40, Km=1, texfreq=35)
{

point PP, center;
float surface_mag, layer_mag, turb, turb1, turb2, f, d, radius, fuzz;
float bump_layer_mag;
float ss, tt;

turb=0; 
fuzz=.05;

/* PP = transform("shader", P);   */

surface_mag = 0;
layer_mag = 0;
bump_layer_mag = 0;

/* overall cloud undulation */
layer_mag = 1 - (.5 + .5 * pow(cos(t), 8) * cos(t * (freq * (1 - cos(t)))));
surface_mag = surface_mag + layer_mag;

/* cloud's turbulent undulations */
layer_mag = .2 * noise(s*3,t*3);
surface_mag = surface_mag + layer_mag;

/* CALCULATE TURBULENCE */
for (f = 1; f < freq; f *= 2) 
  turb += abs(snoise(P * f + 4*PI)) / f;

turb1 = pow(1-turb, 4);
turb2 = pow(turb, 4);

layer_mag = turb;
surface_mag *= layer_mag;

/* output */
/* P = PP * PP + surface_mag * Km * normalize(N); */
P += P * surface_mag * Km * normalize(N);
N = calculatenormal(P);
}