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

const double r1(-0.5);
const double r2(0.75);

double f(double t)
{
  return 1 + 0.5*t + 0.75*(r1 - t)*(r2 - t);
}

int main()
{
  picture(P(-0.75, 0), P(1.25, 1.5), "2 x 1.5in");

  begin();
  P pO(0,0), pX(xmax(), 0), pY(0, ymax()),
    tail(r1, f(r1)), head(r2, f(r2));

  bold();

  line(P(xmin(), 0), P(xmax(), 0));
  line(P(0, ymin()), P(0, ymax()));

  line(tail, head);

  plot(f, r1, r2, 40);

  //  dashed();
  //  dash_size(6);
  line(tail&E_1, tail);
  line(head&E_1, head);

  label(pO, P( 0,-4), "$O$", b);
  label(pX, P( 0,-4), "$X$", b);
  label(pY, P(-2, 0), "$Y$", l);

  label(P(r1,0), P(0, -4), "$a$", b);
  label(P(r2,0), P(0, -4), "$b$", b);

  label(P(r1, f(r1)), P(-2,0), "$A$", l);
  label(P(r2, f(r2)), P( 2,0), "$B$", r);

  label(P(r1, 0.5*f(r1)), P(2,0), "$\\phi(a)$", r);
  label(P(r2, 0.5*f(r2)), P(2,0), "$\\phi(b)$", r);

  label(P(0.25, f(0.25)), P(0,-4), "$P$", b);

  tikz_format();
  end();
}