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

pixels = W:1024 H:1024

x = from -10 to 10 W
y = from -10 to 10 H

x = abs(x)
y = abs(y)

sx = 1
sy = sqrt(3)
#sy = 1.732

ax = mod(x, sx)*2 - sx
ay = mod(y, sy)*2 - sy
a = ax*ax + ay*ay

bx = mod(x+sx*0.5, sx)*2 - sx
by = mod(y+sy*0.5, sy)*2 - sy
b = bx*bx + by*by

r = 0.5*min(a, b)
g = r
b = r
