microbit-oxo.py

import microbit
# background oxo grid at brightness 1
gridImg = microbit.Image("01010\n"
                         "11111\n"
                         "01010\n"
                         "11111\n"
                         "01010\n")

playerBrightness = [5,8]

def check_victory():
    #code slightly altered from http://stackoverflow.com/a/15839640/1499289
    combinations = [
        # horizontal
        ((0,0), (1,0), (2,0)),
        ((0,1), (1,1), (2,1)),
        ((0,2), (1,2), (2,2)),
        # vertical
        ((0,0), (0,1), (0,2)),
        ((1,0), (1,1), (1,2)),
        ((2,0), (2,1), (2,2)),
        # crossed
        ((0,0), (1,1), (2,2)),
        ((2,0), (1,1), (0,2))
    ]

    for coordinates in combinations:
        # our squares in are 0,2,4, so *2
        squares = [microbit.display.get_pixel(x*2,y*2) for x,y in coordinates]
        # cheating, as there's no possibility of this going wrong with our brightness values of 5 and 8
        for i, brightness in enumerate(playerBrightness):
            if sum(squares) == brightness*3:
                return i+1 # returns number of player that won
    return 0

def check_squares_filled():
    coordinates = ((0,0), (1,0), (2,0),
                   (0,1), (1,1), (2,1),
                   (0,2), (1,2), (2,2))
        
    squares = [microbit.display.get_pixel(x*2,y*2) for x,y in coordinates]
    for square in squares:
        if square == 0: return False
    return True
    
def grid():
    microbit.display.show(gridImg)
    
# returns 0 to 4 from -1024 to +1024, empirically calculated
def tilt_scale(a):
    a = a + 1024 # range 0 to 2048
    a = min(a, 2048)
    a = max(a, 0)
    # < 512 = 0, 512-853(512+341) = 1, 853-1194 = 2, 1194-1536 = 3,  1536-2048 = 4
    if a<512: return 0
    if a<853: return 1
    if a<1194: return 2
    if a<1536: return 3
    return 4
    
def get_tilt():
    x,y,z = microbit.accelerometer.get_values()
    #print(x+1024,y+1024,z+1024)
    x = tilt_scale(x)
    y = tilt_scale(y)
    z = tilt_scale(z)
    #print(x,y,z)
    return x,y,z

# play game forever
while True:
    #display grid
    grid()
    won = False
    player = 2 # first loop switches to player 1
    xpos = 2 # start in centre
    ypos = 2
    oldBrightness = 0 # start on dark pixel
    
    while not won:
        player = 3 - player # switch player
        #print("player =",player)
        goodSquare = False # goodSquare = clicked player button on a dark pixel
        while not goodSquare: # loop until blank square selected
            buttonPressed = False
            while not buttonPressed: # loop until button pressed
                #redraw previous (usually current pixel)
                microbit.display.set_pixel(xpos, ypos, oldBrightness)
                xpos,ypos,zpos = get_tilt()
                #print(xpos,ypos)
                # remember old brightness, to restore at top of loop
                oldBrightness = microbit.display.get_pixel(xpos,ypos)
                # make current position max brightness
                microbit.display.set_pixel(xpos, ypos, 9)
                # check if correct player's button is clicked
                buttonPressed = (microbit.button_a.is_pressed() and player == 1) or (microbit.button_b.is_pressed() and player == 2)
                microbit.sleep(100)
            # if dark pixel clicked, good square has been chosen, set brightness for current player 5 or 8
            if oldBrightness == 0:
                goodSquare = True
                #print(xpos,ypos)
                oldBrightness = playerBrightness[player-1]
                microbit.display.set_pixel(xpos,ypos, oldBrightness)
                squaresFilled = check_squares_filled()
                if check_victory()>0:
                    won = True
                elif squaresFilled:
                    won = True
                    player = 3
   
    if player < 3:
        microbit.display.scroll("Player "+str(player)*8+" won!!!")
    else:
        microbit.display.scroll("Draw    ")

This file is public domain