#https://www.shadertoy.com/view/Mlf3RX

pixels = W:1024 H:1024

x = from 0 to 1 W
y = from -0.5 to 0.5 H

px = abs(fract(x)-0.5)
py = abs(fract(y)-0.5)

[loop start: 12
pt = - (px*1.735 - py)*0.865
py = - (abs(px + py*1.735) - 0.58)*0.865
px = pt
loop end]

o = py

r = o
g = o
b = o
