Question

提前感谢您的帮助。我是Python语言的新手，并使用这个项目来学习Python，现在它使用一个函数来绘制瓷砖到屏幕，我正在努力让一个精灵能够通过按键移动。问题是我的函数keyMoveSprite（）无法看到我的全局变量x_coordinate和y_coordinate。它们在我的函数中，但由于x和y变量在每次迭代时被设置为0，因此导致我的精灵不能移动，所以我认为它们需要在循环之外。有什么建议？这是我的代码。我觉得这个问题可能是因为我在游戏的主循环中重复调用了这个函数，但需要反复调用它以跟踪输入。

import pygame,sys
from pygame.locals import *

pygame.init()  

#Global Variables
screen_x = 800
screen_y = 480
screen =  pygame.display.set_mode((screen_x, screen_y))
x_coordinate = 0
y_coordinate = 0
moveX, moveY = 0, 0


#This function will take the screen coordinates and draw
#a tile to the entire screen. It will draw tiles no matter
#the screen size.

def keyMoveSprite():
    sprite = pygame.image.load("character.png").convert_alpha()

    for event in pygame.event.get():

        if event.type == KEYDOWN:
            if event.key == K_LEFT:
                moveX = -10
            elif event.key == K_RIGHT:
                moveX = +10
            elif event.key == K_UP:
                moveY = -10
            elif event.key == K_DOWN:
                moveY = +10

        if event.type == KEYUP:
            if event.key == K_LEFT:
                moveX = 0
            elif event.key == K_RIGHT:
                moveX = 0
            elif event.key == K_UP:
                moveY = 0
            elif event.key == K_DOWN:
                moveY = 0

    x_coordinate = x_coordinate + moveX
    y_coordinate = y_coordinate + moveY

    screen.blit(sprite,(x_coordinate, y_coordinate))
    pygame.display.update()
    print("Character drawn at:", x_coordinate, y_coordinate)


def mapDraw(screen_x, screen_y):



    floor = pygame.image.load("floor_tile.png")
    wall = pygame.image.load("wall_tile.png")
    treasure = pygame.image.load("treasure_chest.png")

# Intialize row for loop
    row = 0
    mapColumn = 0
    mapRow = 0

#Loop between the values 0 to the screen's y variable, in intervals of
#32, and store them in the variable row once per loop.

    mapArray = [
        [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1],
        [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1],
        [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1]
        ]


    for row in range(0, screen_y, 32):
        column = 0 # Set column to 0 per iteration, this allows reset of the x coordinate
        print("Map Row Value:", mapRow)
        mapColumn = 0 # Resets mapColumn variable to 0
        for column in range(0, screen_x, 32):

            if mapArray[mapRow][mapColumn] == 0:

                screen.blit(floor, (column, row)) 
                #print(column,row)
                pygame.display.update()
                #print("Map Column Value:",mapColumn)
                print("MapCol",mapColumn,"MapRow",mapRow)

            elif mapArray[mapRow][mapColumn] == 1:
                screen.blit(wall, (column, row))
                pygame.display.update()







            mapColumn = mapColumn + 1

        mapRow = mapRow + 1


def main():

    mapFloor = mapDraw(800,480)
    while True:

        keyMoveSprite()

main()

Answer 1

尝试使用global keyword，以便口译员可以消除x_coordinate和y_coordinate的本地分配之间的歧义：

def keyMoveSprite():
    global x_coordinate, y_coordinate
    # The rest of your code...

解决这个问题的一个更好的方法是创建一个类来表示你的玩家，它的位置以及与之相关的其他状态，而不是将所有内容存储在全局中。

为什么我的函数keyMoveSprite（）看不到全局变量x_coordinate，y_coordinate？

1 个答案: