Question

我如何通过Pygame界面使玩家移动（带箭头），跳跃，移动流畅（逐渐加速）？

Answer 1

第一步是创建界面：

# import all the modules that we need
import time, pygame
from pygame.locals import *
pygame.init()

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

class Player: # player class
    def __init__(self):
        pass

    def move(self):
        pass

player = Player() # create the player

time_passed = 0
# pygame event loop
while True:
    prev = time.time()
    for event in pygame.event.get():
        if event.type == QUIT: # if the window is closed
            pygame.quit()
            exit()

    screen.fill((220, 220, 255)) # fill with blue sky
    player.move() # update the player
    pygame.display.flip() # update the screen

    time_passed = time.time() - prev
    # used to change the player’s speed regardless of FPS

接下来，我们将不得不初始化播放器。因此，让我们填写Player.__init__函数：

def __init__(self):
    self.x = 400 # middle of the screen
    self.y = 600 # bottom of the screen
    self.moveX = 0 # x speed
    self.moveY = 0 # y speed

    self.image = pygame.image.load('image.png')
    # the image of the player
    self.w, self.h = self.image.get_size()

仅此而已。其次：在屏幕上渲染播放器。播放器的x和y位置位于播放器图像底部的中间。

def move(self):
    self.render()

def render(self):
    x = int(self.x - self.w / 2)
    y = int(self.y - self.h)
    screen.blit(self.image, (x, y))

下一步：在move和moveX进行更改的情况下，填充moveY功能，使玩家可以移动。

def move(self):
    self.x += self.moveX * time_passed # move left-right
    self.y += self.moveY * time_passed # move up-down

    self.moveX *= 0.9 # slow down (decrease speed progressively)
    self.moveY += 5000 * time_passed
                      # the player will go down faster and faster

    if self.y > 600:  # if the player falls out of the screen
                      # you can change 600 by another ground height
        self.y = 600

    # if the player walks over the screen
    if self.x < -self.w / 2:
        self.x = -self.w / 2
    elif self.x > 800 - self.w / 2:
        self.x = 800 - self.w / 2

    self.render() # render once the position is corrected

现在，我们必须允许播放器获取用户事件：

def get_events(self):
    pressed = pygame.key.get_pressed()
    if pressed[K_LEFT]:
        self.moveX -= 50
    if pressed[K_RIGHT]:
        self.moveX += 50
    if pressed[K_UP] and self.y == 600: # if on floor
        self.moveY = -1000

def move(self):
    self.get_events()

    ...

为什么将速度设置为-1000？播放器将上升，然后（move功能中的速度降低）上升得更慢，然后再上升，然后再下降，然后下降。而且尽可能的流畅。

您可以添加反转的图像（使用pygame.transform.flip）以在播放器向一个方向或另一个方向前进时进行切换，或者使用操纵杆命令播放器（使用pygame.joystick），或者添加一个点击功能，将这些代码放入平台游戏中……可能性是无限的。

Answer 2

我建议阅读pygame - Sprite Module Introduction。在pygame - tutorials — wiki和pygame - projects上可以找到很多资源和项目。

对于您的项目Pygame Platformer Tutorial，我特别推荐您。

通过使用pygame.sprite.Sprite，pygame.sprite.Group，pygame.Rect，pygame.time.Clock和pygame.math.Vector2，可以大大简化代码：

import pygame
from pygame.locals import *
pygame.init()
screen = pygame.display.set_mode((800, 600))

class Player(pygame.sprite.Sprite): 
    def __init__(self, x, y):
        super().__init__() 
        self.pos = pygame.math.Vector2(x, y)
        self.move = pygame.math.Vector2()
        try:
            self.image = pygame.image.load('image.png')
        except:
            self.image = pygame.Surface((20, 20))
            self.image.fill((255, 0, 0))
        self.rect = self.image.get_rect(midbottom = (round(self.pos.x), round(self.pos.y)))

    def update(self):
        pressed = pygame.key.get_pressed()
        if pressed[K_LEFT]:
            self.move.x -= 50
        if pressed[K_RIGHT]:
            self.move.x += 50
        if pressed[K_UP]:
            self.move.y = -1000

        self.pos = self.pos + self.move * time_passed
        self.move.x *= 0.8 # slow down (decrease progressively)
        self.move.y += 5000 * time_passed

        if self.pos.y > 600:
            self.pos.y = 600

        self.rect = self.image.get_rect(midbottom = (round(self.pos.x), round(self.pos.y)))
        if self.rect.left < 0:
            self.rect.left = 0
            self.pos.x = self.rect.centerx
        if self.rect.right > 800:
            self.rect.right = 800
            self.pos.x = self.rect.centerx

player = Player(400, 600)
allSprites = pygame.sprite.Group(player)

clock = pygame.time.Clock()
while True:
    time_passed = clock.tick(60) / 1000
    for event in pygame.event.get():
        if event.type == QUIT: 
            pygame.quit()
            exit()
    allSprites.update()

    screen.fill((220, 220, 255))
    allSprites.draw(screen)
    pygame.display.flip()

如何进行逼真的2D播放器运动（跳跃，流畅...）

2 个答案: