I’ve had countless hours working on this university project, to develop a simple python snake and ladder game. I probably wont touch python once this semester is finished, but I rather post it up here for my own reference and to help others to learn how to speak python!
I believe publishing codes as GPLv3 is best way to help all other beginners save time and learn basics of python. I’ve spend hours and hours searching in Google to learn about functions and how to properly use them in Python, so you can instantly save all those hours and learn how to code basic GUI in python using tkinter’s grid and how to properly use arrays, while loops and for loops. It even goes as deep as implementing a multi-threaded timer!
Here you go. Learn first, thank me later: (UPDATE: After publishing this, I noticed WordPress is removing python’s tabbed spaces before each line, so below code don’t work out of box. if you wish to have code with correct intents, use this link instead)
#License: GPLv3
#Developed using Python 3.4.2
#Load tkinter module. it is available by default by python and we just need to import it
from tkinter import *
#Import messagebox and promptbox modules for tkinter
import tkinter.simpledialog
#this is used for color cycle when player reach end of the game
import threading
#try to load PIL (Pillow) module if it is available and drop an error if it is not available
try:
from PIL import ImageTk, Image
except:
print(“Python PIL package not found. Please install it to be able load images correctly.”)
import random
dice_num=0
#Assign array for snake holes colors in labels
SNAKE_HOLES = [48,44, 39,34, 28,13]
#Assign array for ladder bridges colors in labels
LADDER_BRIDGES = [3,8, 6,26, 14,22, 32,49]
#set current position
player_1_pos=0
#count player moves
player_moves=0
#count snake bites
player_bites=0
#count ladder climbs
player_climb=0
#player name variable
player_name=””
#Time holder
time_elapsed=0
def randomColor():
global PlayerMovesLabel
COLORS = [‘red’,’blue’,’yellow’,’pink’,’lightblue’,’steel blue’,’turquoise’,’sandy brown’,’purple’,’violet red’,’violet’,’maroon’,’tomato’,’orange’,’green yellow’]
randomColor = random.randint(0, len(COLORS))
PlayerMovesLabel.config(bg=COLORS[randomColor])
def colorCycle():
global PlayerMovesLabel, time_elapsed
#put it inside try, so that if in middle of color switching, main thread is closed, it don’t crash
try:
#assign our timer
mytimer = threading.Timer(0.2, colorCycle)
#link timer to main thread, so that if main thread is closed, timer get stopped
mytimer.daemon = True
#start timer
mytimer.start()
#if player is in position 50, start the cycle
if player_1_pos==50:
randomColor()
else:
#otherwise keep background white
PlayerMovesLabel.config(bg=’white’)
time_elapsed=time_elapsed+1
except:
#if error, do nothing. error means program has been exited but thread is running for one more last time.
return
def movePlayer():
#define our global variables so that function can access variables outside of its scope
global player_1_pos
global dice_num
global player_moves
global player_bites
global player_climb
global grid_array
global PlayerMovesLabel
global diceRollLabel
global time_elapsed
#If player reach goal, reset the counter and colors
if player_1_pos==50:
player_1_pos=0
player_moves=0
player_1_pos=0
player_bites=0
player_climb=0
grid_array[50-1].config(bg=”white”)
time_elapsed=0
#get our old and new player positions
old_player_pos=player_1_pos
new_player_pos=player_1_pos+dice_num
#if there is snake bite or ladder climb, show feedback message
additional_message=””
#code to take care when move is more than 50
if new_player_pos>50:
new_player_pos=50-(new_player_pos-50)
#detect if player go to snake hole
#enumerate snake holes to get their Index ID and
#go through list of snake holes
for idx,val in enumerate(SNAKE_HOLES):
#in our array, first value (even index number) is snake head, and second value (odd index number) is snake tail, detect head
if idx % 2 == 0:
#if it is head, and player is on head
if new_player_pos==SNAKE_HOLES[idx]:
#move player to tail number
new_player_pos=SNAKE_HOLES[idx+1]
#Update player bites counter
player_bites=player_bites+1
additional_message=”Bitten | ”
#detect if player go to ladder bottom
#enumerate ladder bridges to get their Index ID and
#go through list of ladders
for idx,val in enumerate(LADDER_BRIDGES):
#in our array, first value (even index number) is ladder bottom, and second value (odd index number) is ladder top, detect bottom
if idx % 2 == 0:
#if it is ladder bottom, and player is on bottom of ladder
if new_player_pos==LADDER_BRIDGES[idx]:
#climb the ladder!
new_player_pos=LADDER_BRIDGES[idx+1]
#Update player climb counter
player_climb=player_climb+1
additional_message=”Climb | ”
#change old position to white
if old_player_pos>0:
grid_array[old_player_pos-1].config(bg=”white”)
#change new position to yellow
grid_array[new_player_pos-1].config(bg=”yellow”)
#apply change to player position variable
player_1_pos=new_player_pos
player_moves=player_moves+1
if player_1_pos == 50:
PlayerMovesLabel[‘text’] = “*WON* Move: ” + str(player_moves) + “, Bite: ” + str(player_bites) + “, Climb:” + str(player_climb) + ” *WON*”
tkinter.messagebox.showinfo(“*WON*”, player_name+” Won the game in “+str(player_moves) + ” moves during “+ str(int(time_elapsed/5)) +” seconds!”)
else:
PlayerMovesLabel[‘text’]=additional_message + “Move: ” + str(player_moves) + “, Bite: ” + str(player_bites) + “, Climb:” + str(player_climb)
#function when Roll button is clicked
def rollTheDice():
global dice_num
global diceRollLabel
#get a random number between 1 to 6
dice_num=random.randint(1,6)
#write number into label
diceRollLabel[‘text’]=player_name + ” Rolled: ” + str(dice_num)
#move the player!
movePlayer()
def createGUI():
global grid_array
global PlayerMovesLabel
global diceRollLabel
global diceWindow
global player_name
# create diceWindow
diceWindow = Tk()
# Set title for diceWindow
diceWindow.title(“SNAKE & LADDERS”)
# Make window not resizable
diceWindow.resizable(width=False, height=False)
diceWindow.config(bg=’white’)
# Load logo if PIL module is installed:
try:
#load logo.gif
logoFile=Image.open(“lbg=’white’ogo.gif”)
#resize the image to match field size
logo = logoFile.resize((300, 37), Image.ANTIALIAS)
#define image type
logo = ImageTk.PhotoImage(logo)
#put image into a label
logoContainer = Label(diceWindow, image = logo,bg=’white’)
#show the label
logoContainer.grid(row=0,column=1,columnspan=10)
except:
#otherwise just show a label
RevertLogoImage = Label(diceWindow, text=”Snake & Ladder”,bg=’white’,font=(“Arial”,30))
RevertLogoImage.grid(row=0, column=1, columnspan=10)
print(“Logo rendering has been skipped.”)
#create moves indicator label
PlayerMovesLabel = Label(diceWindow, text=”Please enter your name in popup window”, bg=’white’)
PlayerMovesLabel.grid(row=1,column=1,columnspan=10)
#Create button for GUI
btnRoll = Button(diceWindow, text=”Roll”, command=rollTheDice, width=30)
#show it on screen
btnRoll.grid(row=3,column=1,columnspan=10)
#create our board interface
#define out array of labels first
grid_array = []
for y in range (0,5):
for x in range (0,10):
array_num=((x+1)+(y*10))
grid_array.append(Label(diceWindow, borderwidth=8,text= array_num ))
#get x and y and put them into new variable to avoid editing original x/y variables which can cause infinite loop
xx=x
yy=y
#a simple control to make board-like numbers to position correctly
yy=abs(yy-5)
#reverse the numbers if it is not even row
if not yy % 2:
xx=abs(xx-9)
grid_array[array_num – 1].grid(row= (yy+1) +4,column=(xx+1))
#fix problem with windows OS that don’t show labels in white color by default
grid_array[array_num – 1].config(bg=’white’)
#take care of snake holes, apply custom colors
if array_num in SNAKE_HOLES:
#if it is even index number, means it is snake head
if SNAKE_HOLES.index(array_num) % 2 == 0:
#red is for snake head
grid_array[array_num-1].config(fg=”red”)
else:
#orange is for snake tail
grid_array[array_num-1].config(fg=”orange”)
#take care of ladder bridges, apply custom colors
if array_num in LADDER_BRIDGES:
#if it is even index number, it means it is ladder bottom
if LADDER_BRIDGES.index(array_num) % 2 == 0:
#blue is ladder bottom
grid_array[array_num-1].config(fg=”blue”)
else:
#blue is ladder top
grid_array[array_num-1].config(fg=”lightblue”)
#initialize timer
colorCycle()
#If user cancel promptbox dialog or left name empty, ask again
while player_name==” or player_name is None:
player_name=tkinter.simpledialog.askstring(“Player Name”,”Please enter your name: “)
PlayerMovesLabel[‘text’]=’- Waiting for first Roll -‘
#create introduction label
diceRollLabel = Label(diceWindow, bg=”white”, text=”Welcome “+player_name+”, Please roll your dice!”)
diceRollLabel.grid(row=2,column=1,columnspan=10)
# Establish the window
diceWindow.mainloop()
#create GUI to start things up
createGUI()