#https://www.shadertoy.com/view/XdfyzB

pixels = W:1024 H:1024

x = from -16 to 16 W
y = from -16 to 16 H

a = atan2(y, x)
u = x*cos(a) - y*sin(a)
v = x*sin(a) + y*cos(a)

value = (u * sign(v) + v * sign(u)) * sin(u) * sin(v)
color = sin(value) * 3.0
color = color * sign(u) * sign(v)

b = abs(color)
g = abs(color) - 0.5
r = abs(color) - 1.0
