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

pixels = W:1024 H:1024

x = from -1.0 to 1.0 W
y = from -1.0 to 1.0 H

t = 1.0

a = atan2(y, x)
b = length2(x, y)
v = sin(100.0*(sqrt(b)-0.02*a-0.3*t))

r = clamp(v,0.0,1.0)
g = r
b = r
