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/* -*-ePiX-*- */
#include "epix.h"
using namespace ePiX;
P F(double t, double r)
{
return P(t-r*Sin(t), 1-r*Cos(t)); // a cycloid
}
int main()
{
picture(P(0,0), P(15,27), "4 x 7.2in");
begin();
const double dt(5*M_PI/11);
double t(dt);
for(int i=0; i < 9; ++i, t += dt)
{
screen scr(P(-1,0), P(15,2)); // drawing area
activate(scr);
plain(Black());
line(P(-1, 0), P(15, 0)); // the ground
circle(P(t,1), 1); // the wheel
// [0,t] x [0,1]
domain R(P(0,0), P(t, 1), mesh(10*i,5), mesh((int) ceil(1+4*t), 5));
// the paths
bold();
for (int j=0; j < 6; ++j)
{
pen(RGB(1-0.125*j, 0.125*j, 0.5+0.125*j));
plot(F, R.slice2(0.2*j));
}
// the spoke
bold(Green());
line(P(t,1), F(t,1));
inset(P(0, 25-3*i), P(15, 27-3*i)); // page layout
deactivate(scr);
}
end();
}
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