#!/usr/local/bin/ruby
#
# ./interlace.rb > interlace.gif

require "GD"

# create a new image
im = GD::Image.new(200, 200)

# allocate some colors
white = im.colorAllocate(255,255,255)
black = im.colorAllocate(0,0,0)
red = im.colorAllocate(255,0,0)
green = im.colorAllocate(0,255,0)
blue = im.colorAllocate(0,0,255)
yellow = im.colorAllocate(255,250,205)

STDERR.print im.interlace, "\n"
im.interlace = TRUE
STDERR.print im.interlace, "\n"

im.filledRectangle(0, 0, 50, 50, red)
im.filledRectangle(50, 0, 100, 50, green)
im.filledRectangle(0, 50, 50, 100, blue)
im.filledRectangle(50, 50, 100, 100, yellow)


im.gif STDOUT