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

P O(0,0);
double rad(0.4);

double theta(const P& tail, const P& head)
{
  P tmp(head - tail);
  return Atan2(tmp.x2(), tmp.x1());
}

void ray(const P& tail, const P& head, double t)
{
  line(tail, head + t*(head - tail));
}

int main()
{
  picture(P(0,-1), P(5,1.6), "5 x 2.6in");

  begin();
  degrees();
  bold();

  P A1(0.5,0.5), B1(1.5,1.5), C1(B1.x1(),A1.x2()), A1p(A1&E_1), B1p(B1&E_1);
  P A2(2,-0.75), B2(3, 1.25), C2(B2.x1(),A2.x2()), A2p(A2&E_1), B2p(B2&E_1);
  P A3(4.5,0.6),B3(3.5,1.6), C3(B3.x1(),A3.x2()), A3p(A3&E_1), B3p(B3&E_1);

  line(P(xmin(),0), P(xmax(),0), 10);
  line(A1p, A1); line(A1, B1); line(B1, B1p);
  line(A2p, A2); line(A2, B2); line(B2, B2p);
  line(A3p, A3); line(A3, B3); line(B3, B3p);

  dashed();
  dash_size(6);
  ray(A1, C1, 0.3);
  ray(A2, C2, 0);
  ray(C3, A3, 0.6);

  line(B2, C2);

  ellipse(A1, rad*E_1, rad*E_2, 0, theta(A1, B1), 4);
  ellipse(A2, rad*E_1, rad*E_2, 0, theta(A2, B2), 4);
  ellipse(A3, rad*E_1, rad*E_2, 0, theta(A3, B3), 8);

  label(P(xmin(),0), P(0,-4), "$X'$", b);
  label(P(xmax(),0), P(0,-4), "$X$", b);

  label(A1p, P(0,-4), "$A'$", b);
  label(A2p, P(0, 2), "$A'$", t);
  label(A3p, P(0,-4), "$A'$", b);

  label(B1p, P(0,-4), "$B'$", b);
  label(B2p, P(0,-4), "$B'$", br);
  label(B3p, P(0,-4), "$B'$", b);

  label(A1, P(-2,2), "$A$", tl);
  label(A2, P(0,-4), "$A$", b);
  label(A3, P(2,-4), "$A$", br);

  label(B1, P(0,2), "$B$", t);
  label(B2, P(0,2), "$B$", t);
  label(B3, P(0,2), "$B$", t);

  label(C1, P(2, 2), "$C$", tr);
  label(C2, P(2,-2), "$C$", br);

  tikz_format();
  end();
}