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

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

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

P ptB(0,0), ptA(1,2), ptC(2.125,0);
P ptH(0.5*(norm(ptA) + norm(ptC) + norm(ptA-ptC)), 0);

int main()
{
  picture(P(0, -1), P(3, 2), "4.5 x 4.5in");

  begin();

  double thB(Atan2(ptA.x2(), ptA.x1()));
  P tmp(ptA - ptC);
  double thC(Atan2(tmp.x2(), tmp.x1()));

  Segment BO(ptB, ptB+cis(0.5*thB)), CO(ptC, ptC+cis(0.5*(M_PI+thC)));

  P ptO(BO*CO), ptD(ptO.x1());
  P ptE(ptO - (ptO-ptC)%(ptA-ptC)), ptF(ptO - (ptO-ptB)%(ptA-ptB));

  Segment CK(ptC, ptC - P(0,1)), OK(ptO, ptO + J(ptB - ptO));
  P ptK(CK*OK), ptL(OK*Segment(ptB, ptD));

  const double rad(norm(ptO - ptD));

  triangle(ptA, ptB, ptC);
  circle(ptO, rad);

  line(ptO, ptB);
  line(ptO, ptD);
  line(ptC, ptH, 20);

  line(ptO, ptK);
  line(ptC, ptK);

  line_style("- - - ");
  line(ptO, ptF);

  label(ptA,  LdY, sfmt("A"), t);
  label(ptO, 0.5*(LdX+LdY), sfmt("O"), tr);

  label(ptB, -LdY, sfmt("B"), b);
  label(ptC, 2*LdX-LdY, sfmt("C"), b);
  label(ptD, -LdY, sfmt("D"), b);

  dot(ptH, -LdY, sfmt("H"), b);

  label(ptE,  LdX, sfmt("E"), tr);
  label(ptF, -LdX, sfmt("F"), tl);

  label(ptK, -LdY, sfmt("K"), b);
  label(ptL, -LdY, sfmt("L"), bl);

  tikz_format();
  end();
}