#include "library.h"

// This is the important function to print, with x
// ranging from 0 to 600

double formula(const double x)
{ return 150 + 300*pow(sin(x/24),2)+25*cos(x); }

// but I also want a close connection to this function's
// value too, so I'll use it to colour the other function's
// plot.

double minor_function(const double x)
{ return sin(x/180); }


void internal_plot(const double x, const double last)
{ if (x > last)
    return;
  const double y = formula(x);
  const double m = minor_function(x);
  // use m to choose colour
  set_pen_color_hls(m, 0.5, 1.0);
  draw_to(x, 600-y);
  internal_plot(x+0.1, last); }    

void plot(const double x, const double last)
{ if (x > last)
    return;
  const double y = formula(x);
  move_to(x, 600-y);
  internal_plot(x+0.1, last); }    

void main()
{ make_window(600, 600);
  set_pen_width(2);
  set_pen_color(color::red);
  plot(0, 600); }