Rendering great circle arcs in Processing between two coordinates

greatcirclearc.java

void drawPath(float lat1, float lon1, float lat2, float lon2) {
  stroke(0);
  strokeWeight(5);
  noFill();
  
  lat1 *= PI/180;
  lon1 *= PI/180;
  lat2 *= PI/180;
  lon2 *= PI/180;
  
  beginShape();
  
  float d, f, A, B, x, y, z, latN, lonN;
  int n;
  
  d = 2*asin(sqrt( pow((sin((lat1-lat2)/2)),2) + cos(lat1)*cos(lat2)*pow((sin((lon1-lon2)/2)),2)));  
  println(d);
  
  for (n = 0 ; n < (SENSITIVITY + 1) ; n++ ) {
      f = (1/SENSITIVITY) * n;
      A = sin((1-f)*d)/sin(d);
      B = sin(f*d)/sin(d);
      x = A*cos(lat1)*cos(lon1) +  B*cos(lat2)*cos(lon2);
      y = A*cos(lat1)*sin(lon1) +  B*cos(lat2)*sin(lon2);
      z = A*sin(lat1)           +  B*sin(lat2);
  
      latN = atan2(z,sqrt(pow(x,2)+pow(y,2)));
      lonN = atan2(y,x);
      
      latN /= PI / 180;
      lonN /= PI / 180;      
      
      vertex(lonN, -latN);
      println(latN + " " + lonN);
  }  
  
  endShape();
}