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#include "animation.hpp"
template <int D> class HardSphere : public Sphere<D> {
public:
using Sphere<D>::Sphere;
double U(const Position<D>& y, double ry) const {
if (Sphere<D>::regularizedDistanceSquared(y, ry) < 1) {
return 1e6;
} else {
return 0;
}
}
};
int main(int argc, char* argv[]) {
unsigned N = 1200;
double R = 0.024;
double ε = 0.005;
unsigned steps = 1e6;
initializeAnimation(argc, argv);
Rng r;
Model<2, HardSphere<2>> m(N, 2 * R, gContinuousPolydisperse(R), r);
for (unsigned i = 0; i < steps; i++) {
for (unsigned j = 0; j < N; j++) {
HardSphere<2>& p = r.pick(m.particles);
Position<2> xNew = p.x;
Vector<2> Δx;
for (double& xi : Δx) {
xi = r.variate<double, std::normal_distribution>(0, ε);
}
xNew += Δx;
bool reject = false;
for (const HardSphere<2>* neighbor : m.nl.neighborsOf(xNew)) {
if (neighbor != &p) {
if (neighbor->regularizedDistanceSquared(xNew, p.r) < 1 && neighbor->regularizedDistanceSquared(p.x, p.r) >= 1) {
reject = true;
break;
}
}
}
if (!reject) {
m.move(p, xNew);
}
HardSphere<2>& p1 = r.pick(m.particles);
HardSphere<2>& p2 = r.pick(m.particles);
double rat = p1.r / p2.r;
if (rat < 1.2 && rat > 0.83) {
reject = false;
for (const HardSphere<2>* neighbor : m.nl.neighborsOf(p2.x)) {
if (neighbor != &p1 && neighbor != &p2) {
if (neighbor->regularizedDistanceSquared(p2.x, p1.r) < 1 && neighbor->regularizedDistanceSquared(p1.x, p1.r) >= 1) {
reject = true;
break;
}
}
}
for (const HardSphere<2>* neighbor : m.nl.neighborsOf(p1.x)) {
if (neighbor != &p1 && neighbor != &p2) {
if (neighbor->regularizedDistanceSquared(p1.x, p2.r) < 1 && neighbor->regularizedDistanceSquared(p2.x, p2.r) >= 1) {
reject = true;
break;
}
}
}
if (!reject) {
std::swap(p1.r, p2.r);
}
}
}
if (i % 10 == 0)
draw(m);
}
return 0;
}
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