patterns — packing

generator verdict no votes yet
source — auto/a001_packing.g51_packing
def g51_packing(rng):
    """PACKING — circles claim lattice points by mutual exclusion, then each grows
    only until it would touch its nearest surviving neighbor, so every mark's size
    is set by the collision it avoids rather than by any global rule."""
    N = rng.choice([32, 40, 50, 64])
    c = Canvas(N, "GEOMETRIC", "dots", "packing", tiles=False)
    C = c.C
    nz = Value2D(rng, res=rng.choice([3, 4, 5]))
    base_excl = rng.uniform(1.6, 3.0) * C
    excl_var = rng.uniform(0.3, 1.4) * C
    gap = rng.uniform(0.80, 0.97)

    cells = [(i, j) for i in range(N) for j in range(N)]
    rng.shuffle(cells)

    accepted = []
    for i, j in cells:
        x, y = c.center(i, j)
        u, v = (i + 0.5) / N, (j + 0.5) / N
        local_excl = base_excl + excl_var * nz(u, v)
        blocked = False
        for (ax, ay) in accepted:
            dx = x - ax
            dy = y - ay
            if dx * dx + dy * dy < local_excl * local_excl:
                blocked = True
                break
        if not blocked:
            accepted.append((x, y))

    k = len(accepted)
    for idx in range(k):
        x, y = accepted[idx]
        nearest = None
        for jdx in range(k):
            if jdx == idx:
                continue
            ox, oy = accepted[jdx]
            d = math.hypot(x - ox, y - oy)
            if nearest is None or d < nearest:
                nearest = d
        if nearest is None:
            nearest = C * 2
        r = (nearest / 2.0) * gap
        c.circle(x, y, r)

    return c
generator