# snake-demo.py
from tkinter import *
import random
def init(data):
data.rows = 8
data.cols = 16
data.margin = 5
data.direction = (0, -1)
loadSnakeBoard(data)
placeFood(data)
data.gameOver = False
data.paused = False
data.debugMode = False
def loadSnakeBoard(data):
data.board = []
for row in range(data.rows): data.board += [[0]*data.cols]
headRow = (len(data.board)) // 2
headCol = len(data.board[0]) // 2
data.board[headRow][headCol] = 1
data.headRow = headRow
data.headCol = headCol
def mousePressed(event, data):
pass
def keyPressed(event, data):
if (event.char == "r"): init(data); return
elif (event.char == "p"): data.paused = not data.paused; return
elif (event.char == "d"):
data.debugMode = not data.debugMode
if (data.gameOver or data.paused): return
if (event.keysym == "Left"): data.direction = (0, -1)
elif (event.keysym == "Right"): data.direction = (0, 1)
elif (event.keysym == "Up"): data.direction = (-1, 0)
elif (event.keysym == "Down"): data.direction = ( 1, 0)
takeStep(data)
def timerFired(data):
if (data.paused or data.gameOver): return
takeStep(data)
def takeStep(data):
(drow, dcol) = data.direction
(headRow, headCol) = (data.headRow, data.headCol)
(newHeadRow, newHeadCol) = (headRow + drow, headCol + dcol)
if ((newHeadRow < 0) or (newHeadRow >= data.rows) or
(newHeadCol < 0) or (newHeadCol >= data.cols) or
data.board[newHeadRow][newHeadCol] > 0):
data.gameOver = True
elif data.board[newHeadRow][newHeadCol] == -1:
# eat food
data.board[newHeadRow][newHeadCol]= data.board[headRow][headCol] + 1
(data.headRow, data.headCol) = (newHeadRow, newHeadCol)
placeFood(data)
else:
# didn't eat, so remove old tail (slither forward)
data.board[newHeadRow][newHeadCol] = data.board[headRow][headCol] + 1
(data.headRow, data.headCol) = (newHeadRow, newHeadCol)
removeTail(data)
def placeFood(data):
row = random.randint(0, data.rows - 1)
col = random.randint(0, data.cols - 1)
while data.board[row][col] != 0:
row = random.randint(0, data.rows - 1)
col = random.randint(0, data.cols - 1)
data.board[row][col] = -1
def removeTail(data):
for row in range(data.rows):
for col in range(data.cols):
if data.board[row][col] > 0:
data.board[row][col] -= 1
def drawBoard(canvas, data):
for row in range(data.rows):
for col in range(data.cols):
drawSnakeCell(canvas, data, row, col)
def drawSnakeCell(canvas, data, row,col):
gridWidth = data.width - 2*data.margin
gridHeight = data.height - 2*data.margin
cellWidth = gridWidth / data.cols
cellHeight = gridHeight / data.rows
x0 = data.margin + gridWidth * col / data.cols
x1 = data.margin + gridWidth * (col+1) / data.cols
y0 = data.margin + gridHeight * row / data.rows
y1 = data.margin + gridHeight * (row+1) / data.rows
canvas.create_rectangle(x0, y0, x1, y1, fill="white", outline="black")
if data.board[row][col] > 0:
# draw snake body
canvas.create_oval(x0, y0, x1, y1, fill="blue")
elif data.board[row][col] == -1:
# draw food
canvas.create_oval(x0, y0, x1, y1, fill="green")
if (data.debugMode):
canvas.create_text(x0 + cellWidth/2, y0 + cellHeight/2,
text=str(data.board[row][col]),
font=("Helvatica", 14, "bold"))
def redrawAll(canvas, data):
drawBoard(canvas, data)
if (data.gameOver):
canvas.create_text(data.width/2, data.height/2, text="Game Over!",
font=("Helvetica", 32, "bold"))
####################################
# use the run function as-is
####################################
def run(width=300, height=300):
def redrawAllWrapper(canvas, data):
canvas.delete(ALL)
canvas.create_rectangle(0, 0, data.width, data.height,
fill='white', width=0)
redrawAll(canvas, data)
canvas.update()
def mousePressedWrapper(event, canvas, data):
mousePressed(event, data)
redrawAllWrapper(canvas, data)
def keyPressedWrapper(event, canvas, data):
keyPressed(event, data)
redrawAllWrapper(canvas, data)
def timerFiredWrapper(canvas, data):
timerFired(data)
redrawAllWrapper(canvas, data)
# pause, then call timerFired again
canvas.after(data.timerDelay, timerFiredWrapper, canvas, data)
# Set up data and call init
class Struct(object): pass
data = Struct()
data.width = width
data.height = height
data.timerDelay = 100 # milliseconds
init(data)
# create the root and the canvas
root = Tk()
canvas = Canvas(root, width=data.width, height=data.height)
canvas.pack()
# set up events
root.bind("<Button-1>", lambda event:
mousePressedWrapper(event, canvas, data))
root.bind("<Key>", lambda event:
keyPressedWrapper(event, canvas, data))
timerFiredWrapper(canvas, data)
# and launch the app
root.mainloop() # blocks until window is closed
print("bye!")
run(300, 300)
from tkinter import *
import random
def init(data):
data.rows = 10
data.cols = 10
data.margin = 5 # margin around grid
data.snake = [(data.rows/2, data.cols/2)]
data.direction = (0, +1) # (drow, dcol)
placeFood(data)
data.timerDelay = 250
data.gameOver = False
data.paused = True
# getCellBounds from grid-demo.py
def getCellBounds(row, col, data):
# aka "modelToView"
# returns (x0, y0, x1, y1) corners/bounding box of given cell in grid
gridWidth = data.width - 2*data.margin
gridHeight = data.height - 2*data.margin
x0 = data.margin + gridWidth * col / data.cols
x1 = data.margin + gridWidth * (col+1) / data.cols
y0 = data.margin + gridHeight * row / data.rows
y1 = data.margin + gridHeight * (row+1) / data.rows
return (x0, y0, x1, y1)
def mousePressed(event, data):
data.paused = False
def keyPressed(event, data):
if (event.keysym == "p"): data.paused = True; return
elif (event.keysym == "r"): init(data); return
if (data.paused or data.gameOver): return
if (event.keysym == "Up"): data.direction = (-1, 0)
elif (event.keysym == "Down"): data.direction = (+1, 0)
elif (event.keysym == "Left"): data.direction = (0, -1)
elif (event.keysym == "Right"): data.direction = (0, +1)
# for debugging, take one step on any keypress
takeStep(data)
def timerFired(data):
if (data.paused or data.gameOver): return
takeStep(data)
def takeStep(data):
(drow, dcol) = data.direction
(headRow, headCol) = data.snake[0]
(newRow, newCol) = (headRow+drow, headCol+dcol)
if ((newRow < 0) or (newRow >= data.rows) or
(newCol < 0) or (newCol >= data.cols) or
((newRow, newCol) in data.snake)):
data.gameOver = True
else:
data.snake.insert(0, (newRow, newCol))
if (data.foodPosition == (newRow, newCol)):
placeFood(data)
else:
# didn't eat, so remove old tail (slither forward)
data.snake.pop()
def placeFood(data):
data.foodPosition = None
row0 = random.randint(0, data.rows-1)
col0 = random.randint(0, data.cols-1)
for drow in range(data.rows):
for dcol in range(data.cols):
row = (row0 + drow) % data.rows
col = (col0 + dcol) % data.cols
if (row,col) not in data.snake:
data.foodPosition = (row, col)
return
def drawBoard(canvas, data):
for row in range(data.rows):
for col in range(data.cols):
(x0, y0, x1, y1) = getCellBounds(row, col, data)
canvas.create_rectangle(x0, y0, x1, y1, fill="white")
def drawSnake(canvas, data):
for (row, col) in data.snake:
(x0, y0, x1, y1) = getCellBounds(row, col, data)
canvas.create_oval(x0, y0, x1, y1, fill="blue")
def drawFood(canvas, data):
if (data.foodPosition != None):
(row, col) = data.foodPosition
(x0, y0, x1, y1) = getCellBounds(row, col, data)
canvas.create_oval(x0, y0, x1, y1, fill="green")
def drawGameOver(canvas, data):
if (data.gameOver):
canvas.create_text(data.width/2, data.height/2, text="Game over!",
font="Arial 26 bold")
def redrawAll(canvas, data):
drawBoard(canvas, data)
drawSnake(canvas, data)
drawFood(canvas, data)
drawGameOver(canvas, data)
####################################
# use the run function as-is
####################################
def run(width=300, height=300):
def redrawAllWrapper(canvas, data):
canvas.delete(ALL)
canvas.create_rectangle(0, 0, data.width, data.height,
fill='white', width=0)
redrawAll(canvas, data)
canvas.update()
def mousePressedWrapper(event, canvas, data):
mousePressed(event, data)
redrawAllWrapper(canvas, data)
def keyPressedWrapper(event, canvas, data):
keyPressed(event, data)
redrawAllWrapper(canvas, data)
def timerFiredWrapper(canvas, data):
timerFired(data)
redrawAllWrapper(canvas, data)
# pause, then call timerFired again
canvas.after(data.timerDelay, timerFiredWrapper, canvas, data)
# Set up data and call init
class Struct(object): pass
data = Struct()
data.width = width
data.height = height
data.timerDelay = 100 # milliseconds
init(data)
# create the root and the canvas
root = Tk()
canvas = Canvas(root, width=data.width, height=data.height)
canvas.pack()
# set up events
root.bind("<Button-1>", lambda event:
mousePressedWrapper(event, canvas, data))
root.bind("<Key>", lambda event:
keyPressedWrapper(event, canvas, data))
timerFiredWrapper(canvas, data)
# and launch the app
root.mainloop() # blocks until window is closed
print("bye!")
run(600, 300)
