Shoot

OVERVIEW

This app is a simple game where you have to click/shoot the alien to stop it from reaching the right hand side of the screen.

FILES

• Create a folder called 'Shoot'.
• Inside the Shoot folder create two more folders 'images' and 'sounds'
• Download the files and place them in the appropriate folder

Task 1 - Setup

• Open Mu
  
  
• Choose/change mode to Pygame Zero
  • 
  • 
    
    

• Type the following code to setup the screen and draw the alien

alien = Actor('alien')
alien.topleft = (0, 0)

WIDTH = 450
HEIGHT = 800

def draw():
    screen.fill((0, 0, 0))
    alien.draw()

• The code above
  • Creates the alien
  • Sets the Width and Height of the screen
  • Tells the computer what to draw
    
    

• Save the code in the 'Shoot' folder as 'shoot.py'
• Press play and the game should start with a black background and the Alien in the top left corner.
  • 
  • 

Task 2 - Movement

• Graphics on a computer screen use a different system to the one you are used to in Maths.
• The top left of the screen is (0,0) and the y-axis is positive when going down.
  • 
• Actors in the game use the terms below for positioning 
  
  
  • 
    
    

• Update your code to include the update function which will add 2 to the aliens x position every time update is called.

alien = Actor('alien')
alien.topleft = (0, 0)

WIDTH = 450
HEIGHT = 800

def draw():
    screen.fill((0, 0, 0))
    alien.draw()

def update():
    alien.left = alien.left + 2

• Your game should now move the alien from the left to the right.
  • 

Task 3 - Shooting the Alien

• To shoot the alien you will need to do three things
  
  • Check if the alien has been clicked
  • When clicked subtract 50 from the aliens x position
  • when clicked give the alien a random y position on the screen
    
    
• Update your code to include the 

import random

alien = Actor('alien')
alien.topleft = (0, 0)

WIDTH = 450
HEIGHT = 800

def draw():
    screen.fill((0, 0, 0))
    alien.draw()

def update():
    alien.left = alien.left + 2

def on_mouse_down(pos):
    if alien.collidepoint(pos):
        set_random_position()

def set_random_position():
    alien.left = alien.left - 50
    alien.top = random.randint(0, HEIGHT)

Task 4 - Score

• To add a score to the game you will need to do three things
  
  • Create a variable to store the score
  • Draw the score on the screen
  • Update the score when the alien is clicked

• Update your code to include the score

import random

alien = Actor('alien')
alien.topleft = (0, 0)

WIDTH = 450
HEIGHT = 800
score = 0

def draw():
    screen.fill((0, 0, 0))
    screen.draw.text("Score: " + str(score), (0,0))
    alien.draw()

def update():
    alien.left = alien.left + 2

def on_mouse_down(pos):
    if alien.collidepoint(pos):
        set_random_position()
        global score
        score = score + 1

def set_random_position():
    alien.left = alien.left - 50
    alien.top = random.randint(0, HEIGHT)

Task 5 - End Game

•  To end the game you will need to do two things
  • Check if the alien has went off the screen
  • If the alien goes off the screen display 'game over'
    
    
• Add the code below to display 'Game over' when the alien reaches the screen edge.

import random

alien = Actor('alien')
alien.topleft = (-1000, 0)

WIDTH = 450
HEIGHT = 800
score = 0

def draw():
    screen.fill((0, 0, 0))
    screen.draw.text("Score: " + str(score), (0,0))
    alien.draw()
    if alien.left > WIDTH:
        screen.draw.text("GAME OVER", (0,20))

def update():
    alien.left = alien.left + 2

def on_mouse_down(pos):
    if alien.collidepoint(pos):
        set_random_position()
        global score
        score = score + 1

def set_random_position():
    alien.left = alien.left - 50
    alien.top = random.randint(0, HEIGHT)

Task 6 - Comments

• Comments are used to make your code more readable
• Comments can be written above or on the same line as code
• Comments start with a hashtag
• Add the comments below or use your own

import random # This imports the code that lets you use random numbers

alien = Actor('alien')     # This creates an actor using the graphic 'alien'
alien.topleft = (-1000, 0) # This sets the aliens position to the top left of the screen

WIDTH = 450  # VARIABLE - Set width of screen
HEIGHT = 800 # VARIABLE - Set height of screen
score = 0    # VARIABLE - Store the score

def draw():
    screen.fill((0, 0, 0))                          # Fill black
    screen.draw.text("Score: " + str(score), (0,0)) # Draw score
    alien.draw()                                    # Draw alien
    if alien.left > WIDTH:                          # If alien goes off screen
        screen.draw.text("GAME OVER", (0,20))       # Draw game over

def update():
    alien.left = alien.left + 2 # Add 2 to alien x position

def on_mouse_down(pos):
    if alien.collidepoint(pos): # If alien collides with mouse position
        set_random_position()   # Use set_random_position function
        global score            # We want to use the global variable score
        score = score + 1       # Add one to score

def set_random_position():
    alien.left = alien.left - 50          # Remove 50 from alien x position
    alien.top = random.randint(0, HEIGHT) # Set alien y to random position from 0 to HEIGHTExtension 1 - 

Extension 1 - Sounds and Changing Images

• To make the game more interactive you can include sounds and animation
• The code below will play a sound and change the alien image every time the alien is clicked

import random

alien = Actor('alien')
alien.topleft = (0, 0)

WIDTH = 450
HEIGHT = 800
score = 0

def draw():
    screen.fill((0, 0, 0))
    screen.draw.text("Score: " + str(score), (0,0))
    alien.draw()
    if alien.left > WIDTH:
        screen.draw.text("GAME OVER", (0,20))

def update():
    alien.left = alien.left + 2

def on_mouse_down(pos):
    if alien.collidepoint(pos):
        set_alien_hurt()
        set_random_position()
        globalscore
        score = score + 1

def set_random_position():
    alien.left = alien.left - 50
    alien.top = random.randint(0, HEIGHT)

def set_alien_hurt():
    sounds.eep.play()
    alien.image = 'alien_hurt'
    clock.schedule_unique(set_alien_normal, 0.5)

def set_alien_normal():
    alien.image = 'alien'

• Add comments to the new lines of code explaining what you think each line does.
• If you are unsure of any lines leave them out or ask your teacher.

Extension 2 - Reskin

• Now that the game is working you can add your own style to it.
• Edit the images for the Alien or create your own
• You don't have to keep the theme of aliens 
  • To keep the transparent background of the images you will need to use a graphics application like paint.net
• Here are some examples
  
  
• Will you need to change the code to get the images to work?

Extension 3 - Fixing Text

• The text that displays 'GAME OVER' needs to stand out more
• Edit the code to achieve the following
  • Centre the text on the screen
  • Change the text colour
  • Increase the font size
  • Any other effects you would like
    
    
• The examples below show how you can change the text, use them to help you.

screen.draw.text("Text color", (50, 30), color="orange")

screen.draw.text("Font name and size", (20, 100), fontname="Boogaloo", fontsize=60)

screen.draw.text("Positioned text", topright=(840, 20))

screen.draw.text("Allow me to demonstrate wrapped text.", (90, 210), width=180, lineheight=1.5)

screen.draw.text("Outlined text", (400, 70), owidth=1.5, ocolor=(255,255,0), color=(0,0,0))

screen.draw.text("Drop shadow", (640, 110), shadow=(2,2), scolor="#202020")

screen.draw.text("Color gradient", (540, 170), color="red", gcolor="purple")

screen.draw.text("Transparency", (700, 240), alpha=0.1)

screen.draw.text("Vertical text", midleft=(40, 440), angle=90)

screen.draw.text("Combining the above options",

    midbottom=(427,460), width=360, fontname="Boogaloo", fontsize=48,

    color="#AAFF00", gcolor="#66AA00", owidth=1.5, ocolor="black", alpha=0.8)

Extension 4 - Fixing Random Positions

• When the alien is clicked it is moved to a random y position using this line of code
  
  alien.top = random.randint(0, HEIGHT)
  
  
• This line of code sets the top of the alien to a random number from 0 to the HEIGHT of the screen.
• This means that sometimes the alien goes completely off the bottom of the screen.
• Update the line of code so that the alien will never go off the bottom of the screen
  
  

HINTS

• It is ok for the random number to start at zero but the HEIGHT value moves the alien too far down the screen
• The HEIGHT of the screen is 800
• The height of the alien is 92

Extension 5 - Vertical Mode

• Currently the alien moves from the left to the right of the screen.
• Update the code so that the alien will start at the top of the screen and move down
• Update all parts of the code to ensure the game works correctly.