pixels = W:1024 H:1024

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

ax = 0.2
ay = 0.5
ar = 0.2
bx = 0.8
by = 0.5
br = 0.2

frag = ar/length2(x - ax, y - ay) + br/length2(x - bx, y - by)

k = if (frag > 1, 1, 0)

r = k
g = r
b = r
