from casioplot import set_pixel,get_pixel,show_screen

#default 128px x 64px
length=(128,384)
angles=[(0,1),(1,0),(0,-1),(-1,0)]
white,black=(255,)*3,(0,)*3

ants=[{"coord":[0,0],"angle":0}]
  
while 1:
  for ant in ants:
    color=get_pixel(ant["coord"][0],ant["coord"][1])
    
    set_pixel(ant["coord"][0],ant["coord"][1],black if color==white else white)
    
    ant["angle"]+=1 if color==white else -1
    ant["angle"]&=3

    ant["coord"]=[(ant["coord"][i]+angles[ant["angle"]][i])%length[i] for i in [0,1]]
       
  show_screen()