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

const P LdY(0, 4);
const P LdX(4, 0);

const double rad(sqrt(0.5));
const P ctr1( 0.5,0.5);
const P ctr2(-0.5,0.5);

std::string sfmt(const std::string& msg)
{
#ifdef SANSSERIF
  return "$\\mathsf{"+msg+"}$";
#else
  return "$"+msg+"$";
#endif
}

int main()
{
  picture(P(-1.25,0), P(1.25,1.25), "3.5 x 1.75in");

  begin();

  triangle(P(-1, 0), P(1, 0), P(0,1));

  arc(P(0,0), 1, 0, M_PI);
  arc(ctr2, rad, M_PI_4, 5*M_PI_4);

  pen(2);

  arc(P(0,0), 1, 0, M_PI_2);
  arc(ctr1, rad, -M_PI_4, 3*M_PI_4);

  label(P(-1, 0), -LdY, sfmt("B"), b);
  label(P( 1, 0), -LdY, sfmt("C"), b);
  label(P( 0, 0), -LdY, sfmt("O"), b);

  label(P(0, 1),  2*LdY, sfmt("A"), t);

  label(cis(M_PI_4), 0.5*(LdX+LdY), sfmt("E"), tr);
  label(ctr1+polar(rad, M_PI_4), 0.5*(LdX+LdY), sfmt("D"), tr);

  label(cis(3*M_PI_4), 0.5*(-LdX+LdY), sfmt("G"), tl);
  label(ctr2+polar(rad, 3*M_PI_4), 0.5*(-LdX+LdY), sfmt("F"), tl);

  tikz_format();
  end();
}