#https://www.shadertoy.com/view/lslyR2

pixels = W:1024 H:1024

x = from -0.5 to 0.5 W
y = from -0.5 to 0.5 H

r = length2(x, y)
d = abs(r - 0.3)
a = atan2(y, x)
t = 1.36

s = (0.1 - d)/r*step(d, 0.1)*2

r = sin(t + a - 1)*s
g = sin(t + a - 2)*s
b = sin(t + a - 3)*s
a = sin(t + a)*s
