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

P midpt(const P& tail, const P& head)
{
  return 0.5*(tail + head);
}

int main()
{
  picture(P(0, -1), P(1.5, 1.5), "1.5 x 2.5in");

  begin();
  arrow_inset(0.5);
  arrow_ratio(2);
  arrow_width(2);
  double ma(1), mb(0.4);

  bold();
  P pO(0,0), pA(ma,0), pX(xmax(),0), pY(0, ymax()),
    pB(0,mb), pP(ma, mb),
    pB1(0,ma), pP1(ma, ma),
    pB2(0,-ma), pP2(ma, -ma);

  arrow(P(-0.33, 0), pX);
  arrow(pB2, pY);

  rect(pB2, pP1);
  line(pB, pP);

  label(pO, P(-2,-4), "$O$", bl);
  label(pA, P( 2,-4), "$A$", br);

  label(pX, P(0,-4), "$X$", br);
  label(pY, P(4,-4), "$Y$", r);

  label(midpt(pO, pA), P(0,-4), "$a$", b);
  label(midpt(pO, pB), P(-2,0), "$b$", l);

  label(pB, P(-2,0), "$B$", l);
  label(pP, P( 2,0), "$P$", r);

  label(pB1, P(-2,0), "$B'$", l);
  label(pP1, P( 2,0), "$P'$", r);

  label(pB2, P(-2,0), "$B''$", l);
  label(pP2, P( 2,0), "$P''$", r);

  tikz_format();
  end();
}