使用 Pygame 模块来使你的 Python 平台开启侧滚效果,来让你的玩家自由奔跑。
这是仍在进行中的关于使用 Pygame 模块来在 Python 3 中在创建电脑游戏的第九部分。先前的文章是:
- 通过构建一个简单的掷骰子游戏去学习怎么用 Python 编程
- 使用 Python 和 Pygame 模块构建一个游戏框架
- 如何在你的 Python 游戏中添加一个玩家
- 用 Pygame 使你的游戏角色移动起来
- 如何向你的 Python 游戏中添加一个敌人
- 在 Pygame 游戏中放置平台
- 在你的 Python 游戏中模拟引力
- 为你的 Python 平台类游戏添加跳跃功能
在这一系列关于使用 Pygame 模块来在 Python 3 中创建电脑游戏的先前文章中,你已经设计了你的关卡设计布局,但是你的关卡的一些部分可能已近超出你的屏幕的可视区域。在平台类游戏中,这个问题的普遍解决方案是,像术语“ 侧滚 ”表明的一样,滚动。
滚动的关键是当玩家精灵接近屏的幕边缘时,使在玩家精灵周围的平台移动。这样给予一种错觉,屏幕是一个在游戏世界中穿梭追拍的摄像机。
这个滚动技巧需要两个在屏幕边缘的绝对区域,在绝对区域内的点处,在世界滚动期间,你的化身静止不动。
在侧滚动条中放置卷轴
如果你希望你的玩家能够后退,你需要一个触发点来向前和向后。这两个点仅仅是两个变量。设置它们各个距各个屏幕边缘大约 100 或 200 像素。在你的设置部分中创建变量。在下面的代码中,前两行用于上下文说明,所以仅需要添加这行后的代码:
player_list.add(player)
steps = 10
forwardX = 600
backwardX = 230
在主循环中,查看你的玩家精灵是否在 forwardx
或 backwardx
滚动点处。如果是这样,向左或向右移动使用的平台,取决于世界是向前或向后移动。在下面的代码中,代码的最后三行仅供你参考:
“`
# scroll the world forward
if player.rect.x >= forwardx:
scroll = player.rect.x – forwardx
player.rect.x = forwardx
for p in plat_list:
p.rect.x -= scroll
# scroll the world backward
if player.rect.x <= backwardx:
scroll = backwardx - player.rect.x
player.rect.x = backwardx
for p in plat_list:
p.rect.x += scroll
## scrolling code above
world.blit(backdrop, backdropbox)
player.gravity() # check gravity
player.update()
“`
启动你的游戏,并尝试它。
滚动像预期的一样工作,但是你可能注意到一个发生的小问题,当你滚动你的玩家和非玩家精灵周围的世界时:敌人精灵不随同世界滚动。除非你要你的敌人精灵要无休止地追逐你的玩家,你需要修改敌人代码,以便当你的玩家快速撤退时,敌人被留在后面。
敌人卷轴
在你的主循环中,你必须对卷轴平台为你的敌人的位置的应用相同的规则。因为你的游戏世界将(很可能)有不止一个敌人在其中,该规则应该被应用于你的敌人列表,而不是一个单独的敌人精灵。这是分组类似元素到列表中的优点之一。
前两行用于上下文注释,所以只需添加这两行后面的代码到你的主循环中:
# scroll the world forward
if player.rect.x >= forwardx:
scroll = player.rect.x - forwardx
player.rect.x = forwardx
for p in plat_list:
p.rect.x -= scroll
for e in enemy_list:
e.rect.x -= scroll
来滚向另一个方向:
# scroll the world backward
if player.rect.x <= backwardx:
scroll = backwardx - player.rect.x
player.rect.x = backwardx
for p in plat_list:
p.rect.x += scroll
for e in enemy_list:
e.rect.x += scroll
再次启动游戏,看看发生什么。
这里是到目前为止你已经为这个 Python 平台所写所有的代码:
“`
!/usr/bin/env python3
draw a world
add a player and player control
add player movement
add enemy and basic collision
add platform
add gravity
add jumping
add scrolling
GNU All-Permissive License
Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved. This file is offered as-is,
without any warranty.
import pygame
import sys
import os
”’
Objects
”’
class Platform(pygame.sprite.Sprite):
# x location, y location, img width, img height, img file
def init(self,xloc,yloc,imgw,imgh,img):
pygame.sprite.Sprite.init(self)
self.image = pygame.image.load(os.path.join(‘images’,img)).convert()
self.image.convertalpha()
self.rect = self.image.getrect()
self.rect.y = yloc
self.rect.x = xloc
class Player(pygame.sprite.Sprite):
”’
Spawn a player
”’
def init(self):
pygame.sprite.Sprite.init(self)
self.movex = 0
self.movey = 0
self.frame = 0
self.health = 10
self.collidedelta = 0
self.jumpdelta = 6
self.score = 1
self.images = []
for i in range(1,9):
img = pygame.image.load(os.path.join(‘images’,’hero’ + str(i) + ‘.png’)).convert()
img.convertalpha()
img.setcolorkey(ALPHA)
self.images.append(img)
self.image = self.images[0]
self.rect = self.image.get_rect()
def jump(self,platform_list):
self.jump_delta = 0
def gravity(self):
self.movey += 3.2 # how fast player falls
if self.rect.y > worldy and self.movey >= 0:
self.movey = 0
self.rect.y = worldy-ty
def control(self,x,y):
'''
control player movement
'''
self.movex += x
self.movey += y
def update(self):
'''
Update sprite position
'''
self.rect.x = self.rect.x + self.movex
self.rect.y = self.rect.y + self.movey
# moving left
if self.movex < 0:
self.frame += 1
if self.frame > ani*3:
self.frame = 0
self.image = self.images[self.frame//ani]
# moving right
if self.movex > 0:
self.frame += 1
if self.frame > ani*3:
self.frame = 0
self.image = self.images[(self.frame//ani)+4]
# collisions
enemy_hit_list = pygame.sprite.spritecollide(self, enemy_list, False)
for enemy in enemy_hit_list:
self.health -= 1
#print(self.health)
plat_hit_list = pygame.sprite.spritecollide(self, plat_list, False)
for p in plat_hit_list:
self.collide_delta = 0 # stop jumping
self.movey = 0
if self.rect.y > p.rect.y:
self.rect.y = p.rect.y+ty
else:
self.rect.y = p.rect.y-ty
ground_hit_list = pygame.sprite.spritecollide(self, ground_list, False)
for g in ground_hit_list:
self.movey = 0
self.rect.y = worldy-ty-ty
self.collide_delta = 0 # stop jumping
if self.rect.y > g.rect.y:
self.health -=1
print(self.health)
if self.collide_delta < 6 and self.jump_delta < 6:
self.jump_delta = 6*2
self.movey -= 33 # how high to jump
self.collide_delta += 6
self.jump_delta += 6
class Enemy(pygame.sprite.Sprite):
”’
Spawn an enemy
”’
def init(self,x,y,img):
pygame.sprite.Sprite.init(self)
self.image = pygame.image.load(os.path.join(‘images’,img))
self.movey = 0
#self.image.convertalpha()
#self.image.setcolorkey(ALPHA)
self.rect = self.image.get_rect()
self.rect.x = x
self.rect.y = y
self.counter = 0
def move(self):
'''
enemy movement
'''
distance = 80
speed = 8
self.movey += 3.2
if self.counter >= 0 and self.counter <= distance:
self.rect.x += speed
elif self.counter >= distance and self.counter <= distance*2:
self.rect.x -= speed
else:
self.counter = 0
self.counter += 1
if not self.rect.y >= worldy-ty-ty:
self.rect.y += self.movey
plat_hit_list = pygame.sprite.spritecollide(self, plat_list, False)
for p in plat_hit_list:
self.movey = 0
if self.rect.y > p.rect.y:
self.rect.y = p.rect.y+ty
else:
self.rect.y = p.rect.y-ty
ground_hit_list = pygame.sprite.spritecollide(self, ground_list, False)
for g in ground_hit_list:
self.rect.y = worldy-ty-ty
class Level():
def bad(lvl,eloc):
if lvl == 1:
enemy = Enemy(eloc[0],eloc[1],’yeti.png’) # spawn enemy
enemylist = pygame.sprite.Group() # create enemy group
enemylist.add(enemy) # add enemy to group
if lvl == 2:
print("Level " + str(lvl) )
return enemy_list
def loot(lvl,lloc):
print(lvl)
def ground(lvl,gloc,tx,ty):
ground_list = pygame.sprite.Group()
i=0
if lvl == 1:
while i < len(gloc):
ground = Platform(gloc[i],worldy-ty,tx,ty,'ground.png')
ground_list.add(ground)
i=i+1
if lvl == 2:
print("Level " + str(lvl) )
return ground_list
def platform(lvl,tx,ty):
plat_list = pygame.sprite.Group()
ploc = []
i=0
if lvl == 1:
ploc.append((0,worldy-ty-128,3))
ploc.append((300,worldy-ty-256,3))
ploc.append((500,worldy-ty-128,4))
while i < len(ploc):
j=0
while j <= ploc[i][2]:
plat = Platform((ploc[i][0]+(j*tx)),ploc[i][1],tx,ty,'ground.png')
plat_list.add(plat)
j=j+1
print('run' + str(i) + str(ploc[i]))
i=i+1
if lvl == 2:
print("Level " + str(lvl) )
return plat_list
”’
Setup
”’
worldx = 960
worldy = 720
fps = 40 # frame rate
ani = 4 # animation cycles
clock = pygame.time.Clock()
pygame.init()
main = True
BLUE = (25,25,200)
BLACK = (23,23,23 )
WHITE = (254,254,254)
ALPHA = (0,255,0)
world = pygame.display.setmode([worldx,worldy])
backdrop = pygame.image.load(os.path.join(‘images’,’stage.png’)).convert()
backdropbox = world.getrect()
player = Player() # spawn player
player.rect.x = 0
player.rect.y = 0
playerlist = pygame.sprite.Group()
playerlist.add(player)
steps = 10
forwardx = 600
backwardx = 230
eloc = []
eloc = [200,20]
gloc = []
gloc = [0,630,64,630,128,630,192,630,256,630,320,630,384,630]
tx = 64 #tile size
ty = 64 #tile size
i=0
while i <= (worldx/tx)+tx:
gloc.append(i*tx)
i=i+1
enemylist = Level.bad( 1, eloc )
groundlist = Level.ground( 1,gloc,tx,ty )
plat_list = Level.platform( 1,tx,ty )
”’
Main loop
”’
while main == True:
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit(); sys.exit()
main = False
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_LEFT or event.key == ord('a'):
print("LEFT")
player.control(-steps,0)
if event.key == pygame.K_RIGHT or event.key == ord('d'):
print("RIGHT")
player.control(steps,0)
if event.key == pygame.K_UP or event.key == ord('w'):
print('jump')
if event.type == pygame.KEYUP:
if event.key == pygame.K_LEFT or event.key == ord('a'):
player.control(steps,0)
if event.key == pygame.K_RIGHT or event.key == ord('d'):
player.control(-steps,0)
if event.key == pygame.K_UP or event.key == ord('w'):
player.jump(plat_list)
if event.key == ord('q'):
pygame.quit()
sys.exit()
main = False
# scroll the world forward
if player.rect.x >= forwardx:
scroll = player.rect.x - forwardx
player.rect.x = forwardx
for p in plat_list:
p.rect.x -= scroll
for e in enemy_list:
e.rect.x -= scroll
# scroll the world backward
if player.rect.x <= backwardx:
scroll = backwardx - player.rect.x
player.rect.x = backwardx
for p in plat_list:
p.rect.x += scroll
for e in enemy_list:
e.rect.x += scroll
world.blit(backdrop, backdropbox)
player.gravity() # check gravity
player.update()
player_list.draw(world) #refresh player position
enemy_list.draw(world) # refresh enemies
ground_list.draw(world) # refresh enemies
plat_list.draw(world) # refresh platforms
for e in enemy_list:
e.move()
pygame.display.flip()
clock.tick(fps)
“`
via: https://opensource.com/article/19/12/python-platformer-game-run
作者:Seth Kenlon 选题:lujun9972 译者:robsean 校对:wxy
主题测试文章,只做测试使用。发布者:eason,转转请注明出处:https://aicodev.cn/2020/01/26/%e4%bd%bf%e4%bd%a0%e7%9a%84-python-%e6%b8%b8%e6%88%8f%e7%8e%a9%e5%ae%b6%e8%83%bd%e5%a4%9f%e5%90%91%e5%89%8d%e5%92%8c%e5%90%91%e5%90%8e%e8%b7%91/