this_is_game.py

import pygame
import random
import math
from pygame import mixer

print("")
print("")
print("")
print("This Game Was Created By: ")
print("********************************")
print("********************************")
print("********************************")
print("********************************")
print("............Ahmed E.............")
print("********************************")
print("********************************")
print("********************************")
print("********************************")

print("SCORE")



#initialize the pygame
pygame.init()
#create the screen
screen = pygame.display.set_mode( (800,600) )

#Backround
background = pygame.image.load('background.png')

#Background Sound
mixer.music.load('background.wav')
mixer.music.play(-1)

#Caption and Title
pygame.display.set_caption("Space Invaders")
icon = pygame.image.load("ufo.png")
pygame.display.set_icon(icon)

#Player
playerImg = pygame.image.load("space-invaders.png")
playerX=370
playerY=480
playerX_change=0



#Enemy
num_of_enemies = 6
enemyImg = []
enemyX= []
enemyY= []
enemyX_change= []
enemyY_change= []
for i in range(num_of_enemies):
    enemyImg.append( pygame.image.load("alien.png"))
    enemyX.append(random.randint(0,736))
    enemyY.append(random.randint(20,150))
    enemyX_change.append(4)
    enemyY_change.append(20)

#Bullet
    #Ready --> Not shooted yet
    #Fire  --> The bullet is moving
bulletImg = pygame.image.load("bullet.png")
bulletX=0
bulletY=480
bulletX_change=0
bulletY_change=40
bullet_state='ready'

#Score
score_value=0
font = pygame.font.Font('freesansbold.ttf' , 32)
textX=10
textY=10
def show_score(x,y):
    score = font.render("Score : " + str(score_value) , True , (255,255,255))
    screen.blit(score , (x,y))


#Game Over Text
over = pygame.font.Font('freesansbold.ttf' , 64)
def game_over_text():
    over_text = over.render("GAME OVER"  , True , (255,255,255))
    screen.blit(over_text , (200,250))


def player(x,y):
    screen.blit(playerImg , (x,y))
def enemy(x,y,i):
    screen.blit(enemyImg[i] , (x,y))
def fire_bullet(x,y):
    global bullet_state
    bullet_state="fire"
    screen.blit(bulletImg , (x+16,y+10))

def isCollision(enemyX,enemyY,bulletX,bulletY):
    distance = math.sqrt(math.pow(enemyX-bulletX,2) + math.pow(enemyY-bulletY,2))
    if distance<27:
        return True;
    else:
        return False
    

#Game loop


running  = True
while running:
    #fill by RGB
    screen.fill( (110,140,0) )
    #background
    screen.blit(background , (0,0))
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running= False
            
        if event.type == pygame.KEYDOWN: #Key is pressed
            if event.key == pygame.K_LEFT:
                playerX_change=-5
            if event.key == pygame.K_RIGHT:
                playerX_change=5
            if event.key == pygame.K_SPACE and bullet_state=="ready":
                bullet_sound = mixer.Sound('laser.wav')
                bullet_sound.play()
                bulletX = playerX
                fire_bullet(bulletX,bulletY)
        if event.type == pygame.KEYUP:
            if event.key == pygame.K_LEFT or event.key==pygame.K_RIGHT:
                playerX_change=0
    
    playerX+=playerX_change    
    if playerX<0:
        playerX=0
    elif playerX>736:
        playerX=736
    player(playerX,playerY)
    
    for i in range(num_of_enemies):
        #Game over
        
        if enemyY[i]>400:
            for j in range(num_of_enemies):
                enemyY[j]=2000
            game_over_text()
            break;
            
        
        enemyX[i]+=enemyX_change[i]
        if enemyX[i]<0:
            enemyX_change[i]=4
            enemyY[i]+=enemyY_change[i]
        elif enemyX[i]>736:
            enemyX_change[i]=-4
            enemyY[i]+=enemyY_change[i]    
        
        #Collision
        collision= isCollision(enemyX[i],enemyY[i],bulletX,bulletY)
        if collision:
            collision_sound = mixer.Sound('explosion.wav')
            collision_sound.play()
            bulletY=480
            bullet_state="ready"
            score_value+=1
            enemyX[i]=random.randint(0,800)
            enemyY[i]=random.randint(20,150)
            print(score_value)
        enemy(enemyX[i],enemyY[i]  , i)

        
    #Bullet Movement
    if bullet_state is "fire":
        fire_bullet(bulletX ,bulletY)
        bulletY-=bulletY_change
    if bulletY<=0:
        bulletY=480
        bullet_state="ready" 
    
    
    
    show_score(textX,textY)
    pygame.display.update()