/* -*-ePiX-*- */
#include "epix.h"
using namespace ePiX;

const double rad(0.2); // inner circle

P midpt(const P& tail, const P& head, double t)
{
  return tail + t*(head - tail);
}

int main()
{
  picture(P(-1,-1), P(1,1), "3.5 x 3.5in");

  begin();
  degrees();

  label(P(0, ymin()), P(0,-8), "\\textsc{Fig.~13.}", b);

  arrow_inset(0.5);
  arrow_width(5);
  arrow_ratio(2.5);

  P Sun(polar(rad, 205)), Sun2(polar(rad, 190));
  P Jp(cis(20)), Jp2(cis(5));

  font_size("footnotesize");

  bold();

  circle();
  circle(P(0,0), rad);

  arc_arrow(P(0,0), 0.9, 70, 110);
  arrow(midpt(Jp, Sun2, 0.3), midpt(Jp, Sun2, 0.31));
  arrow(midpt(Sun, Jp2, 0.72), midpt(Sun, Jp2, 0.73));

  dot(Sun,  P(-2,-2), "$S$", bl);
  dot(Sun2, P(-2, 0), "$S'$", l);

  dot(Jp,  P(2,2), "$J$", tr);
  dot(Jp2, P(2,0), "$J'$", r);

  dashed();
  line(Sun, Jp2);
  line(Sun2, Jp);

  tikz_format();
  end();
}