Python 如何在游戏中保持正交运动

我正在使用pygame创建一个游戏，希望限制用户只能左、右、上、下移动，但不能对角移动。我在下面提供的代码允许玩家在屏幕范围内移动。如何停止对角线运动

class player:
    def __init__(self, x, y, width, height, colour):
        self.width = width  # dimensions of player
        self.height = height  # dimensions of player
        self.x = x  # position on the screen
        self.y = y  # position on the screen
        self.colour = colour  # players colour
        self.rect = (x, y, width, height)  # all the players properties in one
        self.vel = 1  # how far/fast you move with each key press

    def draw(self, win):
        pygame.draw.rect(win, self.colour, self.rect)

    def move(self):
        keys = pygame.key.get_pressed()  # dictionary of keys - values of 0/1

        if keys[pygame.K_LEFT]:  # move left: minus from x position value
            if self.x <= 5: # if player tries to go too far left
                pass
            else:
                self.x -= self.vel

        if keys[pygame.K_RIGHT]:  # move right: add to x position value
            if self.x == 785: # if player tries to go too far right
                pass
            else:
                self.x += self.vel

        if keys[pygame.K_UP]:  # move up: minus from y position value
            if self.y <= 105: # if player tries to go too far up
                pass
            else:
                self.y -= self.vel

        if keys[pygame.K_DOWN]:  # move down from
            if self.y >= 785: # if player tries to go too far down
                pass
            else:
                self.y += self.vel

        self.update()

    def update(self):
        self.rect = (self.x, self.y, self.width, self.height)  # redefine where the player is

职业玩家：
定义初始值（自身、x、y、宽度、高度、颜色）：
self.width=宽度#玩家尺寸
self.height=身高#球员尺寸
self.x=x#在屏幕上的位置
self.y=y#在屏幕上的位置
self.color=颜色#玩家颜色
self.rect=（x，y，width，height）#所有玩家属性都在一个
self.vel=1#每次按键移动的距离/速度
def抽签（自我，赢）：
pygame.draw.rect（赢，自我着色，自我校正）
def移动（自我）：
keys=pygame.key.get_pressed（）#键字典-值为0/1
如果键[pygame.K_LEFT]：#向左移动：从x位置值减去
if self.x使控件映射的if块成为if else链，以防止多个键注册每次更新

def move(self):
    keys = pygame.key.get_pressed()  # dictionary of keys - values of 0/1

    if keys[pygame.K_LEFT]:  # move left: minus from x position value
        if self.x <= 5: # if player tries to go too far left
            pass
        else:
            self.x -= self.vel

    elif keys[pygame.K_RIGHT]:  # move right: add to x position value
        if self.x == 785: # if player tries to go too far right
            pass
        else:
            self.x += self.vel

    elif keys[pygame.K_UP]:  # move up: minus from y position value
        if self.y <= 105: # if player tries to go too far up
            pass
        else:
            self.y -= self.vel

    elif keys[pygame.K_DOWN]:  # move down from
        if self.y >= 785: # if player tries to go too far down
            pass
        else:
            self.y += self.vel

    self.update()

def移动（自）：
keys=pygame.key.get_pressed（）#键字典-值为0/1
如果键[pygame.K_LEFT]：#向左移动：从x位置值减去
例如，如果self.x使用
elif
，则用户按向上键和向右键，则只处理向右键而忽略向上键。