滚动限制

Question

我目前正在攻读A级计算机科学课程，我必须为项目创建一个游戏。我知道这段代码可能效率不高但是我想把它保留在我自己的工作中，并且想要一个有两个位的手，我有点卡住了

此代码目前以介绍屏幕开始，一旦在游戏中，向左，向右滚动并在玩家从屏幕上掉落时移除生命。当所有生命都失去时，屏幕上会显示一个游戏

我想知道是否有办法设置滚动屏幕的限制，以便当玩家离开时它停止在某一点滚动并停止播放器在屏幕边缘停止它们掉落。我想将底部平台的最左边设置为边缘，这会强制玩家向右移动

另一个小问题是，是否有任何方法可以减少滞后

如果有更多信息，您需要随时提出询问 任何建议，将不胜感激 谢谢你的帮助

import pygame as pg
import time
import random


pg.init()#initiates pygame

display_height = 690#Creates width and height of screen
display_width = 1024

#Colours
white = (255,255,255) 
black = (0,0,0)
red = (255,0,0)
green = (0,255,0)
blue = (0,0,255)
grass = (24,85,36)
yellow = (255,255,0)
lightGrey = (184,184,184)
grey = (73,71,65)

Robot_height = 99#Height of robot
Robot_width = 112#Width of robot
Bullet_Fired = False
PowerUp_Active = False
Robot_acc = 0.3 #Robot Acceleration
vec = pg.math.Vector2

gameDisplay = pg.display.set_mode((display_width,display_height)) #Sets display properties of window
pg.display.set_caption ("Game") #Title on window
clock = pg.time.Clock()
robotImg = pg.image.load("robot1.png") #Loads robots image
lifeImg = pg.image.load("Life.png")#Loads image from folder
lifeImg = pg.transform.scale(lifeImg, (80, 80))#Sets dimensions of image
backgroundImg = pg.image.load("Background.png")#Loads background image
backgroundImg = pg.transform.scale(backgroundImg, (display_width, display_height))#Sets dimensions of background to fit the screen
inBackgroundImg = pg.image.load("IntroBackground1.png")#Loads intro background
controlsImg = pg.image.load("controls.png")#Loads controls screen background
controlsImg = pg.transform.scale(controlsImg, (display_width, display_height))#Sets dimensions to fit screen
largeText = pg.font.Font("Font.ttf",77)#Large text set
smallText = pg.font.Font("Font.ttf",32)#Small text set

#Class for platforms
class Platform(pg.sprite.Sprite):
    def __init__(self, x,y,w,h):
        pg.sprite.Sprite.__init__(self)
        self.image = pg.Surface((w,h))#sets width and height of platform
        self.image.fill(grass)#Fills rectangle with blue
        self.rect = self.image.get_rect()#Rectangle set
        self.rect.x = x#x position
        self.rect.y = y#y position

#List of platforms
PLATFORM_LIST = [[0,display_height - 40,display_width,40],
                 [display_width + 300,display_height - 40,display_width,40],
                 [display_width /2 - 50,display_height * 3/4,100,20],
                 [display_width -10,display_height * 3/4,100,20]]
#Platform group
platforms = pg.sprite.Group()

#Checks through "PLATFORM_LIST" and adds all the platforms the the grounp "platforms"
for plat in PLATFORM_LIST:
    p = Platform(*plat)
    platforms.add(p)

#Draws platforms to the screen
def draw():
    for plat in platforms:
        pg.draw.rect(gameDisplay, grass, plat)

#Class for robot
class RobotClass(pg.sprite.Sprite):
    def __init__(self):
        pg.sprite.Sprite.__init__(self)
        self.image = pg.Surface((Robot_width,Robot_height))#Height and width of the robot
        self.rect = self.image.get_rect()#Gets rectangle of robot
        self.rect.center = (display_width / 2, display_height / 2)#Location of center of robot
        self.RobotPos = vec(display_width / 2, display_height / 2)#Position of robot as vector
        self.bottom = (0,0)#Bottom of robot
        self.vel = vec(0, 0)#Robots velocity
        self.acc = vec(0, 0.3)#Robots Acceleration

startX = display_width/2
startY = display_height/2

#Creates Robot
Robot = RobotClass()

#Jump function
def jump():
    #Checks pixel below robot to see if there is a collision
    Robot.rect.x = Robot.rect.x +1
    hits = pg.sprite.spritecollide(Robot , platforms, False)
    Robot.rect.x = Robot.rect.x -1
    if hits:
        #Gives robot velocity of 5 upwards
        Robot.vel.y = -10

#Settings for text
def text_objects(text, font):
    textSurface = font.render(text, True, white)
    return textSurface, textSurface.get_rect()

#Displays lives of Robot
def display_lives(lives):
    global lifeImg
    TextSurf, TextRect = text_objects("Lives:", smallText)#Sets text and font
    TextRect.topleft = (1,16)#Places text in top left of screen
    gameDisplay.blit(TextSurf, TextRect) #displays text
    if lives == 3:#Displays 3 spanners
        gameDisplay.blit(lifeImg,(110,0))
        gameDisplay.blit(lifeImg,(160,0))
        gameDisplay.blit(lifeImg,(210,0))
    if lives == 2:#Displays 2 spanners
        gameDisplay.blit(lifeImg,(110,0))
        gameDisplay.blit(lifeImg,(160,0))
    if lives == 1:#Displays 1 spanners
        gameDisplay.blit(lifeImg,(110,0))
    if lives == 0:#Should end game when all lives are lost
        game_over()

#Function for button that takes parameters (message,x,y,height,width,active colour,inactive colour,text size,action)      
def button(msg,x,y,w,h,i,a,t,action=None):
    mouse = pg.mouse.get_pos() #Gets (x,y) position of mouse
    Text = pg.font.Font("Font.ttf",t) #Lets text size be input
    click = pg.mouse.get_pressed() #Gets whenther mouse has been clicked (mouse1,middle mouse,mouse2)

    if x+w > mouse[0] > x and y+50 > mouse[1] > y:#Checks to see if mouse is within boundaries of button
        pg.draw.rect(gameDisplay, a,(x,y,w,h),5)#Changes color of box when being hovered over
        if click[0] == 1 and action != None:#If mouse1 is clicked and there is an action to be performed it will be run
            action()#action is parameter and the () is used to initiate function
    else:
        pg.draw.rect(gameDisplay, i,(x,y,w,h),5)#Sets default button

    TextSurf, TextRect = text_objects(msg, Text)#Runs text_objects with inputted parameter of the message
    TextRect.center = ((x+(w/2)),(y+(h/2)))#Places text inside the button
    gameDisplay.blit(TextSurf, TextRect)#Displays text


def Exit():#Used for button on intro screen to exit
    pg.quit()
    quit()

#What happens when player runs out of lives
def game_over():
    while True:
        for event in pg.event.get():#lets window be closed
            if event.type == pg.QUIT:
                pg.quit()
                quit()
        gameDisplay.blit(inBackgroundImg, (0, 0))
        TextSurf, TextRect = text_objects(("Game"), largeText)#Places large text on screen
        TextRect.center = ((display_width/2+10),(180))#location of text
        gameDisplay.blit(TextSurf, TextRect)
        TextSurf, TextRect = text_objects(("Over"), largeText)
        TextRect.center = ((display_width/2+10),(280))
        gameDisplay.blit(TextSurf, TextRect)
        pg.draw.rect(gameDisplay, yellow,(290,125,445,220),5)#Puts yellow box over game over

        button("Retry",410,600,207,70,yellow,lightGrey,45,game_loop)
        button("Quit",display_width-105,display_height-55,100,50,yellow,lightGrey,33,Exit)

        pg.display.update()#updates screen
        clock.tick(15)

#Function for control screen
def controls():
    while True:
        for event in pg.event.get():#lets window be closed
            if event.type == pg.QUIT:
                pg.quit()
                quit()
        gameDisplay.blit(controlsImg, (0, 0))#Places controlsImg on screen
        button("Back",5,display_height-55,100,50,black,grey,30,game_intro)#places back button in bottom left corner

        pg.display.update()#updates screen
        clock.tick(15)#sets clock rate


#Function to gun the intro screen
def game_intro():
    while True:
        for event in pg.event.get():#lets window be closed
            if event.type == pg.QUIT:
                pg.quit()
                quit()
        gameDisplay.blit(inBackgroundImg, (0, 0))#Places background image
        TextSurf, TextRect = text_objects(("Lost on planet X"), largeText)#Places large text on screen
        TextRect.center = ((display_width/2),(200))#location of text
        gameDisplay.blit(TextSurf, TextRect)#displays text
        pg.draw.rect(gameDisplay, yellow,(65,130,900,150),5)#Puts yellow box over title

        button("Play",412,550,200,50,yellow,lightGrey,36,game_loop) #Play button at middle bottom
        button("Controls",412,450,200,50,yellow,lightGrey,32,controls) #Controls button in middle of screen
        button("Quit",display_width-105,display_height-55,100,50,yellow,lightGrey,33,Exit) #Quit button in bottom right


        pg.display.update()#updates screen
        clock.tick(15)#sets clock rate

#game loop
def game_loop():
    global PLATFORM_LIST
    global startX
    global startY
    global backgroundImg
    Robot.RobotPos = (startX,startY)
    lives = 3 #Robot Lives
    Robot_friction = -0.3 #Friction value
    vec = pg.math.Vector2 #Setting vec as vector quantity
    while True:
        for event in pg.event.get():
            if event.type == pg.QUIT:
                pg.quit
                quit()
            #Starts acceleration when key is pressed
            if event.type == pg.KEYDOWN:
                if event.key == pg.K_LEFT:
                    Robot.acc.x = -Robot_acc
                elif event.key == pg.K_RIGHT:
                    Robot.acc.x = Robot_acc
                elif event.key == pg.K_UP:
                    jump()
            #Adds friction to accleration to slow robot down when key is not being pressed
            if event.type == pg.KEYUP:
                if event.key == pg.K_LEFT or event.key == pg.K_RIGHT:
                    Robot.acc.x = Robot.acc.x * Robot_friction

        #Adjusts velocity of robot by adding the acceleration on each cycle
        Robot.vel = Robot.vel+ Robot.acc
        #gameDisplay.fill(sky)
        gameDisplay.blit(backgroundImg,(0,0))
        #Draws the platforms to the screen and adds them to platform group
        draw()
        #Changes Robot position according to its velocity,acceleration and the friction
        Robot.RobotPos = Robot.RobotPos + Robot.vel + 0.5 * Robot.acc
        #Loads robot onto screen
        gameDisplay.blit(robotImg,(Robot.rect))
        #pg.draw.rect(gameDisplay, red, Robot.rect, 2
        display_lives(lives)#lives
        pg.display.update()#Updates display
        clock.tick(60)

        #Sets bottom of robot to its position
        Robot.rect.midbottom =  Robot.RobotPos

        #Collision detection
        if Robot.vel.y > 0:
            hits = pg.sprite.spritecollide(Robot , platforms, False)
            if hits:
                #Puts Robot on top of platform
                Robot.RobotPos.y = hits[0].rect.top + 1
                Robot.vel.y = 0        
        #Scrolling
        if Robot.rect.left < display_width/4:
            Robot.RobotPos.x = Robot.RobotPos.x + abs(Robot.vel.x)
            startX = startX + abs(Robot.vel.x)
            for plat in platforms:
                plat.rect.x = plat.rect.x + int(abs(Robot.vel.x))
                draw()
        if Robot.rect.right > (display_width-display_width/4):
            Robot.RobotPos.x = Robot.RobotPos.x - abs(Robot.vel.x)
            startX = startX - abs(Robot.vel.x)
            for plat in platforms:
                plat.rect.x = plat.rect.x - int(abs(Robot.vel.x))
                draw()

        #Losing a life
        if Robot.rect.top > display_height:
            lives = lives - 1
            Robot.RobotPos.y = Robot.RobotPos.y - (40+Robot_height)
            Robot.RobotPos.x = Robot.RobotPos.x - 200
            Robot.vel.x = 0


        #Sets top velocity of robot    
        if Robot.vel.x > 6:
            Robot.vel.x = 6
        if Robot.vel.x < -6:
            Robot.vel.x = -6
        #Makes robot velocity = 0 when it is close to 0
        if Robot.vel.x < 0.05 and Robot.vel.x > -0.05:
            Robot.acc.x = 0
            Robot.vel.x = 0

game_intro()
pg.quit()
quit()

Answer 1

我设法自己完成了这个问题，所以我将简要解释一下我做了什么。

我添加了一个名为off set的变量，它跟踪滚动屏幕离原始位置有多远。

offset = 0

然后我将此变量添加到我的滚动代码

中

if Robot.rect.left < display_width/4:
            Robot.RobotPos.x = Robot.RobotPos.x + abs(Robot.vel.x)
            startX = startX + int(abs(Robot.vel.x))
            offset = offset + int(abs(Robot.vel.x))
            for plat in platforms:
                plat.rect.x = plat.rect.x + int(abs(Robot.vel.x))
            for coin in coins:
                coin.rect.x = coin.rect.x + int(abs(Robot.vel.x))

if Robot.rect.right > (display_width-display_width/4):
            Robot.RobotPos.x = Robot.RobotPos.x - abs(Robot.vel.x)
            startX = startX - int(abs(Robot.vel.x))
            offset = offset - int(abs(Robot.vel.x))
            for plat in platforms:
                plat.rect.x = plat.rect.x - int(abs(Robot.vel.x))
            for coin in coins:
                coin.rect.x = coin.rect.x - int(abs(Robot.vel.x))

然后我在这个函数中添加了一个额外的if。 当偏移小于零时，这仅在代码中运行滚动部分。任何大于零的值都表示屏幕已偏移到左侧。因此，此代码仅允许您在不在屏幕边缘时滚动

if offset > 0:
            pass
elif Robot.rect.left < display_width/4:
            Robot.RobotPos.x = Robot.RobotPos.x + abs(Robot.vel.x)
            startX = startX + int(abs(Robot.vel.x))
            offset = offset + int(abs(Robot.vel.x))
            for plat in platforms:
                plat.rect.x = plat.rect.x + int(abs(Robot.vel.x))
            for coin in coins:
                coin.rect.x = coin.rect.x + int(abs(Robot.vel.x))

然后停止精灵从屏幕上掉下来我使用我的平台功能在边缘添加了一个墙，并将其添加到一个组中，以防我以后需要使用更多的墙。

w1 = Platform(0,0,10,display_height)
wall = pg.sprite.Group()
wall.add(w1)

在此之后，我使用spritecollide创建了一个条件来检查精灵是否正在接触墙

hit = pg.sprite.spritecollide(Robot , wall,False)
        if hit:
            Robot.vel.x = 0
            Robot.acc.x = 0

虽然这有效但是精灵很难从墙上移开，因为它的速度一直被设置为0所以我添加了另一个变量来检查左箭头是否被按下

hit = pg.sprite.spritecollide(Robot , wall,False)
        if hit:
            if left == True:
                Robot.vel.x = 0
                Robot.acc.x = 0

这只会在您尝试向左移动时重置值

if event.type == pg.KEYDOWN:
                if event.key == pg.K_LEFT:
                    Robot.acc.x = -Robot_acc
                    left = True
                elif event.key == pg.K_RIGHT:
                    Robot.acc.x = Robot_acc                  
                elif event.key == pg.K_UP:
                    jump()
            elif Robot.acc.x < 0:
                left = True
            else:
                left = False 

以下是我的所有代码，以防我遗漏任何内容或者您想要查看不同的部分。

* edit此代码当前不会滚动或显示墙。滚动无关紧要，因为机器人在滚动时应该在屏幕中间，所以墙壁仍然会在那里，但是没有办法与它碰撞，它是不可见的，所以你看不到它

如果我没有很好地解释某个部分，或者您只是想要更多信息，请随意提问。

import pygame as pg
import time
import random


pg.init()#initiates pygame

display_height = 690#Creates width and height of screen
display_width = 1024

#Colours
white = (255,255,255) 
black = (0,0,0)
red = (255,0,0)
green = (0,255,0)
blue = (0,0,255)
grass = (24,85,36)
yellow = (255,255,0)
lightGrey = (184,184,184)
grey = (73,71,65)
brown = (66, 40, 13) 

Robot_height = 99#Height of robot
Robot_width = 112#Width of robot
Bullet_Fired = False
PowerUp_Active = False
Robot_acc = 0.3 #Robot Acceleration
vec = pg.math.Vector2

gameDisplay = pg.display.set_mode((display_width,display_height)) #Sets display properties of window
pg.display.set_caption ("Game") #Title on window
clock = pg.time.Clock()
robotImg = pg.image.load("robot1.png") #Loads robots image
lifeImg = pg.image.load("Life.png")#Loads image from folder
lifeImg = pg.transform.scale(lifeImg, (80, 80))#Sets dimensions of image
backgroundImg = pg.image.load("Background.png")#Loads background image
backgroundImg = pg.transform.scale(backgroundImg, (display_width, display_height))#Sets dimensions of background to fit the screen
inBackgroundImg = pg.image.load("IntroBackground1.png")#Loads intro background
controlsImg = pg.image.load("controls.png")#Loads controls screen background
controlsImg = pg.transform.scale(controlsImg, (display_width, display_height))#Sets dimensions to fit screen
largeText = pg.font.Font("Font.ttf",77)#Large text set
smallText = pg.font.Font("Font.ttf",32)#Small text set

#Class for platforms
class Platform(pg.sprite.Sprite):
    def __init__(self, x,y,w,h):
        pg.sprite.Sprite.__init__(self)
        self.image = pg.Surface((w,h))#sets width and height of platform
        self.image.fill(grass)#Fills rectangle with blue
        self.rect = self.image.get_rect()#Rectangle set
        self.rect.x = x#x position
        self.rect.y = y#y position

#List of platforms x , y , width , height
PLATFORM_LIST = [[-5,display_height - 40,2005,40],
                 [2300,display_height - 40,1000,40],
                 [1100,display_height - 190,300,20],
                 ]
#Platform group
platforms = pg.sprite.Group()

w1 = Platform(0,0,10,display_height)
wall = pg.sprite.Group()
wall.add(w1)

#Checks through "PLATFORM_LIST" and adds all the platforms the the grounp "platforms"
for plat in PLATFORM_LIST:
    p = Platform(*plat)
    platforms.add(p)

#Draws platforms to the screen
def draw():
    for plat in platforms:
        pg.draw.rect(gameDisplay, grass, plat)

#Class for robot
class RobotClass(pg.sprite.Sprite):
    def __init__(self):
        pg.sprite.Sprite.__init__(self)
        self.image = pg.Surface((Robot_width,Robot_height))#Height and width of the robot
        self.rect = self.image.get_rect()#Gets rectangle of robot
        self.rect.center = (display_width / 2, display_height / 2)#Location of center of robot
        self.RobotPos = vec(display_width / 2, display_height / 2)#Position of robot as vector
        self.bottom = (0,0)#Bottom of robot
        self.vel = vec(0, 0)#Robots velocity
        self.acc = vec(0, 0.3)#Robots Acceleration

startX = display_width/2
startY = display_height/2

#Creates Robot
Robot = RobotClass()

#Jump function
def jump():
    #Checks pixel below robot to see if there is a collision
    Robot.rect.x = Robot.rect.x +1
    hits = pg.sprite.spritecollide(Robot , platforms, False)
    Robot.rect.x = Robot.rect.x -1
    if hits:
        #Gives robot velocity of 5 upwards
        Robot.vel.y = -10

#Settings for text
def text_objects(text, font):
    textSurface = font.render(text, True, white)
    return textSurface, textSurface.get_rect()

#Displays lives of Robot
def display_lives(lives):
    global lifeImg
    TextSurf, TextRect = text_objects("Lives:", smallText)#Sets text and font
    TextRect.topleft = (1,16)#Places text in top left of screen
    gameDisplay.blit(TextSurf, TextRect) #displays text
    if lives == 3:#Displays 3 spanners
        gameDisplay.blit(lifeImg,(110,0))
        gameDisplay.blit(lifeImg,(160,0))
        gameDisplay.blit(lifeImg,(210,0))
    if lives == 2:#Displays 2 spanners
        gameDisplay.blit(lifeImg,(110,0))
        gameDisplay.blit(lifeImg,(160,0))
    if lives == 1:#Displays 1 spanners
        gameDisplay.blit(lifeImg,(110,0))
    if lives == 0:#Should end game when all lives are lost
        game_over()

#Displays score in top right of screen and takes in parameter score
def display_score(score):
    #Displays the score itself
    TextSurf, TextRect = text_objects(str(score), smallText)#Sets text and font
    TextRect.topleft = (display_width-120,16)#Places text in top left of screen
    gameDisplay.blit(TextSurf, TextRect)

    #Displays the text "score" infront of the score
    TextSurf, TextRect = text_objects("Score:", smallText)#Sets text and font
    TextRect.topleft = (display_width-255,16)#Places text in top left of screen
    gameDisplay.blit(TextSurf, TextRect)

#Function for button that takes parameters (message,x,y,height,width,active colour,inactive colour,text size,action)      
def button(msg,x,y,w,h,i,a,t,action=None):
    mouse = pg.mouse.get_pos() #Gets (x,y) position of mouse
    Text = pg.font.Font("Font.ttf",t) #Lets text size be input
    click = pg.mouse.get_pressed() #Gets whenther mouse has been clicked (mouse1,middle mouse,mouse2)

    if x+w > mouse[0] > x and y+50 > mouse[1] > y:#Checks to see if mouse is within boundaries of button
        pg.draw.rect(gameDisplay, a,(x,y,w,h),5)#Changes color of box when being hovered over
        if click[0] == 1 and action != None:#If mouse1 is clicked and there is an action to be performed it will be run
            action()#action is parameter and the () is used to initiate function
    else:
        pg.draw.rect(gameDisplay, i,(x,y,w,h),5)#Sets default button

    TextSurf, TextRect = text_objects(msg, Text)#Runs text_objects with inputted parameter of the message
    TextRect.center = ((x+(w/2)),(y+(h/2)))#Places text inside the button
    gameDisplay.blit(TextSurf, TextRect)#Displays text


def Exit():#Used for button on intro screen to exit
    pg.quit()
    quit()

#What happens when player runs out of lives
def game_over():
    while True:
        for event in pg.event.get():#lets window be closed
            if event.type == pg.QUIT:
                pg.quit()
                quit()
        gameDisplay.blit(inBackgroundImg, (0, 0))
        TextSurf, TextRect = text_objects(("Game"), largeText)#Places large text on screen
        TextRect.center = ((display_width/2+10),(180))#location of text
        gameDisplay.blit(TextSurf, TextRect)
        TextSurf, TextRect = text_objects(("Over"), largeText)
        TextRect.center = ((display_width/2+10),(280))
        gameDisplay.blit(TextSurf, TextRect)
        pg.draw.rect(gameDisplay, yellow,(290,125,445,220),5)#Puts yellow box over game over

        button("Retry",410,600,207,70,yellow,lightGrey,45,game_loop)
        button("Quit",display_width-105,display_height-55,100,50,yellow,lightGrey,33,Exit)

        pg.display.update()#updates screen
        clock.tick(15)

#Function for control screen
def controls():
    while True:
        for event in pg.event.get():#lets window be closed
            if event.type == pg.QUIT:
                pg.quit()
                quit()
        gameDisplay.blit(controlsImg, (0, 0))#Places controlsImg on screen
        button("Back",5,display_height-55,100,50,black,grey,30,game_intro)#places back button in bottom left corner

        pg.display.update()#updates screen
        clock.tick(15)#sets clock rate


#Function to gun the intro screen
def game_intro():
    while True:
        for event in pg.event.get():#lets window be closed
            if event.type == pg.QUIT:
                pg.quit()
                quit()
        gameDisplay.blit(inBackgroundImg, (0, 0))#Places background image
        TextSurf, TextRect = text_objects(("Lost on planet X"), largeText)#Places large text on screen
        TextRect.center = ((display_width/2),(200))#location of text
        gameDisplay.blit(TextSurf, TextRect)#displays text
        pg.draw.rect(gameDisplay, yellow,(65,130,900,150),5)#Puts yellow box over title

        button("Play",412,550,200,50,yellow,lightGrey,36,game_loop) #Play button at middle bottom
        button("Controls",412,450,200,50,yellow,lightGrey,32,controls) #Controls button in middle of screen
        button("Quit",display_width-105,display_height-55,100,50,yellow,lightGrey,33,Exit) #Quit button in bottom right


        pg.display.update()#updates screen
        clock.tick(15)#sets clock rate

#game loop
def game_loop():
    left = False
    offset = 0
    global PLATFORM_LIST
    global startX
    global startY
    global backgroundImg
    Robot.RobotPos = (startX,startY)
    score = 0 #Score
    lives = 3 #Robot Lives
    Robot_friction = -0.3 #Friction value
    vec = pg.math.Vector2 #Setting vec as vector quantity
    while True:
        for event in pg.event.get():
            if event.type == pg.QUIT:
                pg.quit
                quit()
            #Starts acceleration when key is pressed
            if event.type == pg.KEYDOWN:
                if event.key == pg.K_LEFT:
                    Robot.acc.x = -Robot_acc
                    left = True
                elif event.key == pg.K_RIGHT:
                    Robot.acc.x = Robot_acc                  
                elif event.key == pg.K_UP:
                    jump()
            elif Robot.acc.x < 0:
                left = True
            else:
                left = False 

            print(left)
            #Adds friction to accleration to slow robot down when key is not being pressed
            if event.type == pg.KEYUP:
                if event.key == pg.K_LEFT or event.key == pg.K_RIGHT:
                    Robot.acc.x = Robot.acc.x * Robot_friction

        #Adjusts velocity of robot by adding the acceleration on each cycle
        Robot.vel = Robot.vel+ Robot.acc
        #gameDisplay.fill(sky)
        gameDisplay.blit(backgroundImg,(0,0))
        #Changes Robot position according to its velocity,acceleration and the friction
        Robot.RobotPos = Robot.RobotPos + Robot.vel + 0.5 * Robot.acc
        #Loads robot onto screen
        gameDisplay.blit(robotImg,(Robot.rect))
        #pg.draw.rect(gameDisplay, red, Robot.rect, 2
        display_lives(lives)
        display_score(score)#lives

        #Sets bottom of robot to its position
        Robot.rect.midbottom =  Robot.RobotPos

        #Collision detection
        if Robot.vel.y > 0:
            hits = pg.sprite.spritecollide(Robot , platforms, False)
            if hits:
                if Robot.RobotPos.y < hits[0].rect.bottom:
                    #Puts Robot on top of platform
                    Robot.RobotPos.y = hits[0].rect.top + 1
                    Robot.vel.y = 0

        hit = pg.sprite.spritecollide(Robot , wall,False)
        if hit:
            if left == True:
                Robot.vel.x = 0
                Robot.acc.x = 0
            else:
                pass

        #Scrolling
        if offset > 0:
            pass
        elif Robot.rect.left < display_width/4:
            Robot.RobotPos.x = Robot.RobotPos.x + abs(Robot.vel.x)
            startX = startX + int(abs(Robot.vel.x))
            offset = offset + int(abs(Robot.vel.x))
            for plat in platforms:
                plat.rect.x = plat.rect.x + int(abs(Robot.vel.x))

        if Robot.rect.right > (display_width-display_width/4):
            Robot.RobotPos.x = Robot.RobotPos.x - abs(Robot.vel.x)
            startX = startX - int(abs(Robot.vel.x))
            offset = offset - int(abs(Robot.vel.x))
            for plat in platforms:
                plat.rect.x = plat.rect.x - int(abs(Robot.vel.x))

        draw()

        #Losing a life
        if Robot.rect.top > display_height:
            lives = lives - 1
            Robot.RobotPos.y = Robot.RobotPos.y - (40+Robot_height)
            Robot.RobotPos.x = Robot.RobotPos.x - 200
            Robot.vel.x = 0


        #Sets top velocity of robot    
        if Robot.vel.x > 6:
            Robot.vel.x = 6
        if Robot.vel.x < -6:
            Robot.vel.x = -6
        #Makes robot velocity = 0 when it is close to 0
        if Robot.vel.x < 0.05 and Robot.vel.x > -0.05:
            Robot.acc.x = 0
            Robot.vel.x = 0

        pg.display.update()#Updates display
        clock.tick(60)

game_intro()
pg.quit()
quit()