Welcome folks today in this blog post we will be building a snake and apples game in turtle library in python. All the full source code of the application is shown below.

Get Started

In order to get started you need to install the following library using the below command

pip install turtle

After installing this library you need to create an app.py file and copy paste the following code

app.py

import turtle
import time
import random


delay = 0.1
queue =[]

#Calculate the score and high score
pen = turtle.Turtle()
pen.shape('square')
pen.penup()
pen.speed(0)
pen.color('White')

pen.hideturtle()
pen.goto(0,210)
pen.write("Score: 0    High score: 0   ",align='center',font=('Arial',25,'bold'))


# First , we create the snake window
window = turtle.Screen()
window.bgcolor('Black')
window.title('Snake_Game by Mariam Mostafa')
window.setup(width=600,height=500)
window.tracer(0)

#Next, we will create the snake head
Snake_Head = turtle.Turtle()
Snake_Head.speed(0)
Snake_Head.shape('circle')
Snake_Head.color('Beige')
Snake_Head.penup()
Snake_Head.goto(0,0) # by default it is in the center of the screen
Snake_Head.direction ='stop'

#Next, we will create the snake food
Snake_Food = turtle.Turtle()
Snake_Food.speed(0)
Snake_Food.shape('circle')

Snake_Food.color('green')
Snake_Food.penup()
Snake_Food.goto(0,150) # by default it is in the center of the screen



########################################################################
# Then , we will create all functions that we need to make snake move
def Move_Snake():
    if Snake_Head.direction == 'up':
        y = Snake_Head.ycor()
        Snake_Head.sety(y + 10)
    if Snake_Head.direction == 'down':
        y = Snake_Head.ycor()
        Snake_Head.sety(y - 10)
    if Snake_Head.direction == 'left':
        x = Snake_Head.xcor()
        Snake_Head.setx(x - 10)
    if Snake_Head.direction == 'right':
        x = Snake_Head.xcor()
        Snake_Head.setx(x + 10)


def go_up():
    Snake_Head.direction = 'up'


def go_down():
    Snake_Head.direction = 'down'


def go_left():
    Snake_Head.direction = 'left'


def go_right():
    Snake_Head.direction = 'right'


def Food_Collision():
    if Snake_Head.distance(
            Snake_Food) < 15:  # I choose 10 or 15 based on the incremental that we use to make the snakehead move
        Snake_Food.goto(random.randint(-290, 290), random.randint(-249, 249))
        """ here we use random numbers in order to move the snake food. that range because of the width and the height of the screen   """
        Snake_body = turtle.Turtle()  # after eating the food the snake became bigger so i create one more turtle and add all in list
        Snake_body.speed(0)
        Snake_body.shape('circle')
        Snake_body.color('yellow')
        Snake_body.penup()
        queue.append(Snake_body)
        return True
    return False


def Border_Collision():
    # Border collision
    if Snake_Head.xcor() > 290 or Snake_Head.xcor() < -290 or Snake_Head.ycor() > 249 or Snake_Head.ycor() < -249:
        time.sleep(1)
        Snake_Head.goto(0, 0)
        Snake_Head.direction = 'stop'
        for segment in queue:
            segment.goto(1000, 1000)
        queue.clear()
        return True

    return False
def Body_Collision():
    # body collisions
    for segment in queue:
        if segment.distance(Snake_Head) < 10:  # overlapping
            time.sleep(1)
            Snake_Head.goto(0, 0)
            Snake_Head.direction = 'stop'
            for segment in queue:
                segment.goto(1000, 1000)
            queue.clear()
            return True
    return False


def Add_Snake_Body():
    # add body to the snake because i don't know the length so i iterate from the last one in the list
    for i in range(len(queue) - 1, 0, -1):
        if i % 5 == 0:
            queue[i].goto(queue[i - 1].xcor(), queue[i - 1].ycor())
            queue[i].color('green')
            continue
        queue[i].goto(queue[i - 1].xcor(), queue[i - 1].ycor())
    if len(queue) > 0:
        queue[0].goto(Snake_Head.xcor(), Snake_Head.ycor())



# after that , i want to direct the snake head by using the keyboard so i should use keyboard bindings  so we use listen function in order to listen to the keypress
window.listen()
window.onkeypress(go_up, 'Up')
window.onkeypress(go_down, 'Down')
window.onkeypress(go_left, 'Left')
window.onkeypress(go_right, 'Right')

####################################################################################
    # Game loop
score = 0
High_Score = 0
while True:

    window.update()
    Move_Snake()
    if Food_Collision():
        score += 10
        High_Score += 10
        if score > High_Score:
            High_Score = score
        pen.clear()
        pen.write('Score:{}    High score:{}  '.format(score, High_Score), align='center', font=('Arial', 25, 'bold'))

    if Body_Collision() or Border_Collision():
        score = 0
        pen.clear()
        pen.write('Score:{}    High score:{}  '.format(score, High_Score), align='center', font=('Arial', 25, 'bold'))
    time.sleep(delay)
    Add_Snake_Body()


# this keep the window open
window.mainloop()

And now if you execute the python script by typing the below command as shown below

python app.py