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

pixels = W:1024 H:1024

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

n = 14.45

circle = x*x+y*y
tunnel = sqrt(circle*0.25)/circle*4.0+n*8.0
wally = sin(atan2(y, x)*8.0+cos(n/2.0)*16.0*sin(tunnel+n)/4.0+sin(n/3.2)*32.0)

shade = clamp(circle*16.0,0.0,1.0)
full=(sin(tunnel)*wally)

r = full*shade*1.4
g = (full-0.25)*shade
b = abs(full+0.5)*shade

