def g53_windrows(rng):
"""WINDROWS — anisotropic scaling: each lattice mark is a rectangle stretched
along a smooth direction field, its stretch ratio set by a second noise
channel so combed regions run long and calm regions stay near square."""
N = rng.choice([24, 32, 40, 50])
c = Canvas(N, "GEOMETRIC", "squares", "windrows", tiles=False)
C = c.C
ang_noise = Value2D(rng, res=rng.choice([2, 3, 4]))
mag_noise = Value2D(rng, res=rng.choice([3, 4, 5]))
ang_scale = rng.uniform(1.2, 2.4)
base_ang = rng.uniform(0, 360)
thick = rng.uniform(0.34, 0.52) * C
stretch_min = rng.uniform(1.1, 1.6)
stretch_max = rng.uniform(2.2, 3.4)
for i in range(N):
for j in range(N):
u, v = (i + 0.5) / N, (j + 0.5) / N
theta = base_ang + (ang_noise(u, v) - 0.5) * 360 * ang_scale
m = mag_noise(u, v)
stretch = stretch_min + (stretch_max - stretch_min) * m
length = thick * stretch
x, y = c.center(i, j)
c.rect(x, y, thick, length, rot=theta)
return c
