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

const double tau(0.4);
double MAX(3.5);

P boost(const P& arg, double t)
{
  double CSH(cosh(t)), SNH(sinh(t));
  double x(arg.x1()), y(arg.x2());

  return P(CSH*x + SNH*y, CSH*y + SNH*x);
}

std::string math(const std::string& arg)
{
  return "$" + arg + "$";
}

const double mx(0.75);
void time_grid(double t,
	       const std::string& lbl1,
	       const std::string& lbl2)
{
  P sw(boost(P(-mx,0), t)), se(boost(P(mx,0), t));
  P we(boost(P(-mx,1), t)), ea(boost(P(mx,1), t));
  P nw(boost(P(-mx,2), t)), ne(boost(P(mx,2), t));

  line(sw, se);
  line(we, ea);
  line(ne, nw);

  line(P(0,0), boost(P(0,2.75), t));

  label(P(0,0), P(0,-2), math(lbl1), b);
  // label(nw, P(-4,2), math(lbl2), l);
  label(boost(P(0,2), t), P(2,-2), math(lbl2), br);
}


void cigar(double T, const std::string& lbl)
{
  P end(boost(P(0, 2), T));
  line(P(0,0), end);
  label(end, P(0,4), math(lbl), t);
}


int main()
{
  picture(P(0,0), P(1.5, 1), "3 x 2in");

  begin();

  label(P(0.5*xmax(), ymin()), P(0,-16), "\\textsc{Fig.~8.}", b);

  screen scr1(P(-1,0), P(2,3)), scr2(P(-0.75,0), P(0.75,3));

  bold();
  font_size("footnotesize");

  activate(scr1);
  pen(1.5);
  cigar(0, "M");

  bold();
  dashed();
  time_grid(tau, "L", "N");
  solid();

  inset(P(0,0), P(1,1));
  deactivate(scr1);

  activate(scr2);
  pen(1.5);
  cigar(tau, "N'");
  bold();

  dashed();
  time_grid(0, "L'", "M'");

  inset(P(1,0), P(1.5,1));
  deactivate(scr2);

  tikz_format();
  end();
}