如何实施终点线？

Question

我想做的是，一旦一辆车冲过终点线，我希望它说出哪辆车赢得了比赛，但我如何才能将其添加到我的游戏中？代码工作正常，只是想看看如何向它添加更多功能，例如信号或某种类型的通知，说明哪辆车先通过了终点线。

import pygame

pygame.init()
#Setting up our colors that we are going to use
GREEN = (20, 255, 140)
GREY = (210, 210, 210)
WHITE = (255, 255, 255)
RED = (255, 0, 0)
PURPLE = (255, 0, 255)
BLACKWHITE =(96, 96, 96)

SCREENWIDTH = 400
SCREENHEIGHT = 500

size = (SCREENWIDTH, SCREENHEIGHT)
screen = pygame.display.set_mode(size)
pygame.display.set_caption("Car Racing")
Icon = pygame.image.load("image/redca_iconr.png")
pygame.display.set_icon((Icon))
# This will be a list that will contain all the sprites we intend to use in our game.
#all_sprites_list = pygame.sprite.Group()

#player
playerIMG = pygame.image.load("image/red_racecar.png")
playerX = 250
playerY = 450
playerCar_position = 0


#player2
playerIMG_two = pygame.image.load("image/greencar.png")
playerX_two = 150
playerY_two = 450
playerCar_position_two = 0


#player3
playerIMG_three = pygame.image.load("image/Orangecar.png")
playerX_three = 50
playerY_three = 450
playerCar_position_three = 0

#player4
playerIMG_four = pygame.image.load("image/yellow_car.png")
playerX_four = 200
playerY_four = 450
playerCar_position_four = 0

#Putting cars to the screen
def player(x, y):
    screen.blit(playerIMG, (x, y))

def player_two(x, y):
    screen.blit(playerIMG_two, (x, y))

def player_three(x, y):
    screen.blit(playerIMG_three, (x, y))

def player_four(x, y):
    screen.blit(playerIMG_four, (x, y))


# Main game loop
run = True
clock = pygame.time.Clock()
#TIP - lots of our actions take place in our while loop cause we want the function/program to run consistently
while run:
    # Drawing on Screen
    screen.fill(GREEN)
    # Draw The Road
    pygame.draw.rect(screen, GREY, [40, 0, 300, 500])
    # Draw Line painting on the road
    pygame.draw.line(screen, WHITE, [185, 0], [185, 500], 5)
    #Finish line
    pygame.draw.rect(screen, BLACKWHITE, [50, 50, 280, 40])
    pygame.draw.line(screen, WHITE, [65, 70], [300, 70], 5)
    font = pygame.font.SysFont("Papyrus", 45)
    text = font.render("Finish line!", 1, (150, 50, 25))
    screen.blit(text, (195 - (text.get_width() / 2), 15))
**Here is where the finish line code is at just want too add some type of notafication saying which car has crossed the finsh line first!**

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False
            # Number of frames per secong e.g. 60
            clock.tick(60)

        keys = pygame.key.get_pressed()

        if keys[pygame.K_1]:
            playerCar_position = -0.1
        if keys[pygame.K_q]:
            playerCar_position = 0.1
        if keys[pygame.K_2]:
            playerCar_position_two = -0.1
        if keys[pygame.K_w]:
            playerCar_position_two = 0.1
        if keys[pygame.K_3]:
            playerCar_position_three = -0.1
        if keys[pygame.K_e]:
            playerCar_position_three = 0.1

        # our functions
    playerY += playerCar_position
    playerY_two += playerCar_position_two
    playerY_three += playerCar_position_three

    player(playerX, playerY)
    player_two(playerX_two, playerY_two)
    player_three(playerX_three, playerY_three)
    player_four(playerX_four, playerY_four)


    # Refresh Screen
    pygame.display.flip()


pygame.quit()

Answer 1

想象一下终点线实际上是一个矩形。鉴于终点线从 [65, 70] 到 [300, 70]，这为我们提供了一个位于 (65,70) 的 235 像素宽的矩形。为了让事情更安全，我们可以使用更宽的矩形作为线条，以防汽车在更新中移动许多像素......只是这样它就不会在没有进入它的情况下“跳跃”线。

finish_line_rect = pygame.Rect( 65,70, 235,32 )           # but 32 pixels wide

然后每辆车移动的时候，可以用pygame.Rect.collidepoint()和每辆车的x,y看是否和finish_line_rect重合。

例如：

# Move the Players' cars 
playerY += playerCar_position
playerY_two += playerCar_position_two
playerY_three += playerCar_position_three

# Draw the Players' cars
player(playerX, playerY)
player_two(playerX_two, playerY_two)
player_three(playerX_three, playerY_three)
player_four(playerX_four, playerY_four)

# Did anyone cross the line?
if ( finish_line_rect.collidepoint( playerX, playerY ) ):
    print( "Player (one) has crossed into finish rectangle" )
if ( finish_line_rect.collidepoint( playerX_two, playerY_two ) ):
    print( "Player two has crossed into finish rectangle" )
# ETC.

Answer 2

首先，我认为您应该创建一个“汽车”class，以免重复太多代码并使其更易于使用。关于终点线，我会做以下事情：

#Create an array with all cars X value
CarPositions = [Car1_x, Car2_x, Car3_x, Car4_x]

#Define X value of Finishline
Finishline = 600

def CheckPosition(CarPositions, Finishline):
    for i in range(len(CarPositions)):
       if CarPositions[i] >= Finishline:
          return CarPositions[i]

您应该按数字顺序排列 X 位置数组，即数组中汽车 1 在汽车 2 之前。这样for循环中的i代表第几辆车通过了。

如何实施终点线？

How to Implement finish line?

python

pygame

sprite

pycharm