include<iostream>
using namespace std;
#include<cmath>
#define PI 3.14159265359
#define T px + scale * r * cos(theta), py + scale * r * sin(theta)
float sx, sy;
float sdCircle(float px, float py, float r)
{
float dx = px - sx, dy = py - sy;
return sqrt(dx * dx + dy * dy) - r;
}
float opUnion(float d1, float d2)
{
return d1 < d2 ? d1 : d2;
}
float f(float px, float py, float theta, float scale, int n)
{
float d = 0.0f;
for (float r = 0.0f; r < 0.8f; r += 0.02f)
{
d = opUnion(d, sdCircle(T, 0.05f * scale * (0.95f - r)));
}
if (n > 0)
{
for (int t = -1; t <= 1; t += 2)
{
float tt = theta + t * 1.8f;
float ss = scale * 0.9f;
for (float r = 0.2f; r < 0.8f; r += 0.1f)
{
d = opUnion(d, f(T, tt, ss * 0.5f, n - 1));
ss *= 0.8f;
}
}
}
return d;
}
int main()
{
cout << "\t\t********** Merry Christmas ! **********" << endl;
cout << endl;
int n = 3;
for (sy = 0.8f; sy > 0.0f; sy -= 0.02f, cout << endl)
{
for (sx = -0.
