I suppose it is possible to have a game that goes on ...and on...and on ...and on, but usually most games end, and therefore must have some sort of parameters set up for the player to "lose" or "die" and the game to be over. With that in mind, this code shows you how to add a "Game Over" feature, which is linked to certain requirements being met -in this case collision with the blue (enemy) stickman will result in certain death!
import pygame
import random
import sys
# Define some colors
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
GREEN = (0, 255, 0)
RED = (255, 0, 0)
BLUE = (0, 0, 255)
#Set the max speed the player can move - changing this value can increase/decrease difficulty
PLAYER_SPEED = 15
#set the max speed the AI can move - changing this value can increase/decrease difficulty
AI_SPEED = 5
#set the max speed the ball can move - changing this value can increase/decrease difficulty
BALL_SPEED = 7
#set the size of the ball - changing this value can increase/decrease difficulty
BALL_SIZE = 10
#Draws the game over box on the screen for when we have collided
#With the AI player
def draw_game_over(screen):
pygame.draw.rect(screen, WHITE, (200, 200, 300, 100), 0) #Draw a white box for the text to sit in
font = pygame.font.Font(None, 36) #Choose the font for the text
text = font.render("Game Over!", 1, BLACK) #Create the text for "GAME OVER"
screen.blit(text, (280, 220)) #Draw the text on the screen
text = font.render("You hit the other player!", 1, BLACK) #Create the text for "You hit the other player"
screen.blit(text, (210, 260)) #Draw the text on the screen
font = pygame.font.Font(None, 28) #Make the font a bit smaller for this bit
text = font.render("Press P to play again. Press E to quit the game.", 1, WHITE) #Create text for instructions on what to do now
screen.blit(text, (100, 350)) #Draw the text on the screen
#Create the text used to display the score and draw it on the screen
def draw_score(screen, x, y, score):
font = pygame.font.Font(None, 36) #Choose the font for the text
text = font.render("Score = " + str(score), 1, WHITE) #Create the text
screen.blit(text, (x, y)) #Draw the text on the screen
#This function draws the ball
def draw_ball(screen, x, y):
pygame.draw.circle(screen, GREEN, [x, y], BALL_SIZE, 0)
background_image = 'background.jpg' #file name of the background image
#This function draws the background on the screen
#max_x and max_y are the maximum x and y values of the screen
def draw_background(screen, file_name):
myimage = pygame.image.load(file_name)
imagerect = myimage.get_rect()
screen.blit(myimage, imagerect)
#This function draws the smaller user-controllable stick figure on the screen
#Colour and scale paramaters have been added to the stick figure so that different varieties of stick figure
#Can be produced whilst using the same function, with the scale being used
#to adjust the size of the stick figure, and the colour being used to set the colour of the stick figures body.
def draw_stick_figure(screen, x, y, colour, scale):
# Draw the Head
#Each value is adjusted by the scale paramater to adjust the size of the stick figure
#We have to convert this value to an int as scale may be a float, a type that is not
#accepted by pygame.draw.ellipse
pygame.draw.ellipse(screen, BLACK, [int(1 * scale) + x, y, int(10 * scale), int(10 * scale)], 0)
# Legs
#Right leg (colour, length of leg....)
pygame.draw.line(screen, BLACK, [int(5 * scale) + x, int(17 * scale) + y], [int(10 * scale) + x, int(27 * scale) + y], int(2 * scale))
#Left Leg
pygame.draw.line(screen, BLACK, [int(5 * scale) + x, int(17 * scale) + y], [x, int(27 * scale) + y], int(2 * scale))
# Body
pygame.draw.line(screen, colour, [int(5 * scale) + x, int(17 * scale) + y], [int(5 * scale) + x, int(7 * scale) + y], int(2 * scale))
# Arms
pygame.draw.line(screen, colour, [int(5 * scale) + x, int(7 * scale) + y], [int(9 * scale) + x, int(17 * scale) + y], int(2 * scale))
pygame.draw.line(screen, colour, [int(5 * scale) + x, int(7 * scale) + y], [int(1 * scale) + x, int(17 * scale) + y], int(2 * scale))
#This function ensures that the number entered is between the range of the min and max values (inclusive).
#If the number is outside of this range, we return the closest allowed value. I.e. if the max was 10 and the number
#entered was 12, 10 would be returned as this is the maximum value allowed
def keep_in_range(number, min_no, max_no):
if (number < min_no):
return min_no
elif (number > max_no):
return max_no
else:
return number
# Setup
pygame.init()
# Set the width and height of the screen [width,height]
screen_size = [700, 500]
screen = pygame.display.set_mode(screen_size)
pygame.display.set_caption("My Game")
#A boolean variable that stores whever the game is over
#Starts off set to False
game_over = False
# Loop until the user clicks the close button.
done = False
# Used to manage how fast the screen updates
clock = pygame.time.Clock()
#Counts the number of times the screen has been redrawn, incremented for every pygame.display.flip()
step = 0
#Stores the score of the player
score = 0
#Stores the step at which the last score was made
#Starts with a value of -100 so we can score on the first step of the game
last_score_step = -100
# Hide the mouse cursor
pygame.mouse.set_visible(0)
# Speed in pixels per frame
x_speed = 0
y_speed = 0
# Current position
x_coord = 300
y_coord = 1
#AI Players current position
ai_x_coord = 300
ai_y_coord = 300
#The AI players last position
old_ai_x_coord = 300
old_ai_y_coord = 300
ai_moves = (-AI_SPEED, 0, AI_SPEED) #A list of moves that the ai player can make each turn
#stores the current direction the ai character is moving
ai_x_direction = 0
ai_y_direction = 0
#Balls current position
ball_x_coord = 300
ball_y_coord = 300
old_ball_x_coord = 300
old_ball_y_coord = 300
#Controls the different moves the ball can make, change these values
#To change the ball speed
ball_moves = (-BALL_SPEED, BALL_SPEED)
ball_x_directon = 0
ball_y_direction = 0
# -------- Main Program Loop -----------
while not done:
# --- Event Processing
for event in pygame.event.get():
if event.type == pygame.QUIT:
done = True
# User pressed down on a key
elif event.type == pygame.KEYDOWN:
# Figure out if it was an arrow key. If so
# adjust speed.
if event.key == pygame.K_LEFT:
x_speed = -PLAYER_SPEED
elif event.key == pygame.K_RIGHT:
x_speed = PLAYER_SPEED
elif event.key == pygame.K_UP:
y_speed = -PLAYER_SPEED
elif event.key == pygame.K_DOWN:
y_speed = PLAYER_SPEED
#If the game over boolean is true, then we are on the game over screen
#Players therefore have multiple options for what to do on these screens
if (game_over):
#If they press p, they have decided to play again, therefore we reset all the variables
#and set game_over to False so the player can try again
if event.key == pygame.K_p:
score = 0
step = 0
last_score_step = 0
x_coord = 300
y_coord = 1
ai_x_coord = 300
ai_y_coord = 300
game_over = False
#If they press e, they have decided to quit, so we exit the game
elif event.key == pygame.K_e:
sys.exit() #call sys.exit() to close the window and exit the game
# User let up on a key
elif event.type == pygame.KEYUP:
# If it is an arrow key, reset vector back to zero
if event.key == pygame.K_LEFT or event.key == pygame.K_RIGHT:
x_speed = 0
elif event.key == pygame.K_UP or event.key == pygame.K_DOWN:
y_speed = 0
# --- Game Logic
# Move the object according to the speed vector.
x_coord = x_coord + x_speed
y_coord = y_coord + y_speed
if (x_coord < 0):
x_coord = 0
if (y_coord < 0):
y_coord = 0
#Adjust the x and y co-ordinates to ensure that the stick figure is kept on the screen and can't
#travel off of it
x_coord = keep_in_range(x_coord, 0, screen_size[0] - 10) #We adjust the upper limit of our allowed range to match the stick figures width
y_coord = keep_in_range(y_coord, 0, screen_size[1] - 27) #We adjust the upper limit of our allowed range to match the stick figures height
#MOVE THE AI PLAYER
#Every 30 steps (screen draws) we change the direction the ai player is moving in
#This makes the movement of the ai player look more realistic. This works because
#step % 30 is gives the remained when the value step is divided by 30, which will only
#occur every 30 steps. You can experiment with changing this value and seeing how the ai
#character moves
if (step % 30 == 0):
ai_x_direction = random.choice(ai_moves)
ai_y_direction = random.choice(ai_moves)
#Update the old ai co-ordinate values
old_ai_x_coord = ai_x_coord
old_ai_y_coord = ai_y_coord
#move the ai player in the chosen direction
ai_x_coord = ai_x_coord + ai_x_direction
ai_y_coord = ai_y_coord + ai_y_direction
#Limit the ai character to ensure it stays on the screen
ai_x_coord = keep_in_range(ai_x_coord, 0, screen_size[0] - 20)
ai_y_coord = keep_in_range(ai_y_coord, 0, screen_size[1] - 54)
#If our x co-ordinate has not changed, then we could have collided with a screen edge so we reverse the direction
#This helps to keep the movement looking natural by preventing the ai player from repeatedly
#moving along the edge of the screen
if (ai_x_coord == old_ai_x_coord):
ai_x_direction *= -1;
#the same is true for the y co-ordinate
if (ai_y_coord == old_ai_y_coord):
ai_y_direction *= -1;
#MOVE THE BALL
#Randomly move the ball basically in the same way as the ai player
#Every 50 steps update the ball direction with a new random one
if (step % 50 == 0):
ball_x_direction = random.choice(ball_moves)
ball_y_direction = random.choice(ball_moves)
#update the old ball coord
old_ball_x_coord = ball_x_coord
old_ball_y_coord = ball_y_coord
#Move the ball in the chosen direction
ball_x_coord += ball_x_direction
ball_y_coord += ball_y_direction
ball_x_coord = keep_in_range(ball_x_coord, 0, screen_size[0])
ball_y_coord = keep_in_range(ball_y_coord, 0, screen_size[1])
#If our x co-ordinate has not changed, then we could have collided with a screen edge so we reverse the direction
#This helps to keep the movement looking natural by preventing the ai player from repeatedly
#moving along the edge of the screen
if (ball_x_coord == old_ball_x_coord):
ball_x_direction *= -1;
#the same is true for the y co-ordinate
if (ball_y_coord == old_ball_y_coord):
ball_y_direction *= -1;
#Tests if the ball has collided with the player
if (ball_x_coord - BALL_SIZE <= x_coord + 5) and (ball_x_coord + BALL_SIZE >= x_coord - 5) and (ball_y_coord - BALL_SIZE <= y_coord + 27) and (ball_y_coord + BALL_SIZE >= y_coord):
#Register the score if it is more than 10 steps after the last score
#This is necessary as the ball has a habit of double bouncing against the player
#Meaning that we register multiple hits with only one true collision
if (last_score_step + 10 < step):
score += 10; #increment the score
#reverse the ball direction
ball_x_directon *= -1
ball_y_direction *= -1
last_score_step = step #record the step at which this score is made
print(score)
#Test if the player has collided with the ai
if (x_coord - 5 <= ai_x_coord + 10) and (x_coord + 5 >= ai_x_coord) and (y_coord - 3 <= ai_y_coord + 54) and (y_coord + 27 >= ai_y_coord):
print("COLLIDED WITH AI")
game_over = True #set the game over boolean to True so we can trigger the end of the game
# --- Drawing Code
# First, clear the screen to WHITE. Don't put other drawing commands
# above this, or they will be erased with this command.
screen.fill(WHITE) #erase the previous screen
draw_background(screen, background_image) #draw the background
#If the game isn't over. we draw the game
if not game_over:
draw_stick_figure(screen, x_coord, y_coord, RED, 1) #draw the user controlled stick figure on the screen
draw_stick_figure(screen, ai_x_coord, ai_y_coord, BLUE, 2) #draw the ai controlled stick figure on the screen
draw_ball(screen, ball_x_coord, ball_y_coord)
#Draw the score on the screen
draw_score(screen, 550, 450, score)
#Else if the game is over (i.e. because we collided with the ai player)
#We print the game over screen
else:
draw_game_over(screen) #draw the game over screen
# Go ahead and update the screen with what we've drawn.
pygame.display.flip()
step += 1#increment step
# Limit frames per second
clock.tick(60)
# Close the window and quit.
pygame.quit()