new   
#
size 256,256   
type png
name temp.png

# background fill, all white
fill   1,1,255,255,255

# line from top to bottom, 50 pixels from left edge, colour black
line   50,0,50,255,0,0,0

# fill in the left region a revolting pastel green
filltoborder 20,20,0,0,0,0,255,127