require "bitmap"

local w, h = 512, 512
local bmp = bitmap.of(w, h, color.black, "Munching_squares")
for x = 0, w - 1 do
    for y = 0, h - 1 do
        local c = (x ~ y) & 255
        bmp:set(x, y, b.rgbColor(255 - c, c // 2, c))
    end
end
bmp:view(false, "", "", true)