有没有办法让我的精灵在没有平台的情况下跳跃?

Is there a way to make my sprite jump without a platform?

现在我的玩家精灵可以向右或向左移动。我已经为我的播放器设置了重力,并且正如预期的那样它从屏幕上掉了下来。我已经阅读了很多关于如何让精灵跳跃的文档。然而,他们都用平台作为精灵可以着陆和移动的基地来解释它。为此,他们加载平台图像或使用 pygame 创建一些图像。但在编写大量代码之前,我已经为我的游戏绘制了一个背景,其中包括地面。所以我不想为我的游戏创建新平台(暂时)。有没有办法让我的精灵在不使用平台的情况下在我的程序中跳跃?我的一个想法是将“平台”设置为我的 y 轴上的某条线。但是我该怎么做呢?我愿意接受任何想法。预先感谢。我的代码分为 3 个文件:main.py、settings.py 和 Sprite1.py。这里是 main.py:

import pygame
import os
import sys
import time
from pygame import mixer
from Sprite1 import *
from settings import *

'''
Setup
'''
pygame.init()

clock = pygame.time.Clock()

pygame.mixer.music.load('.\sounds\Fairy.mp3')
pygame.mixer.music.play(-1, 0.0)

all_sprites = pygame.sprite.Group()
player = Player(all_sprites)


player.rect.x = 50
player.rect.y = 500




showStartScreen(surface)

'''
Main loop
'''

main = True



while main == True:

    background = pygame.image.load(os.path.join('images', 'Bg.png'))
    surface.blit(background, (0,0))



    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'):
                player.control(-steps,0)

            if event.key == pygame.K_RIGHT or event.key == ord('d'):
                player.control(steps,0)

            if event.key == pygame.K_SPACE:
                player.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_SPACE:
                player.jump_cut()

    dt = clock.tick(60) / 1000
    all_sprites.update(dt)
    player.update(dt)
    all_sprites.draw(surface) #refresh player position
    pygame.display.flip()

这里是settings.py:

import pygame

width = 960
height = 720
fps = 40        # frame rate
pygame.display.set_caption('B.S.G.')
surface = pygame.display.set_mode((width, height))
PLAYER_ACC = 0.5
PLAYER_FRICTION = -0.12
PLAYER_GRAV = 0.8
PLAYER_JUMP = 20
PLAYER_LAYER = 2
PLATFORM_LAYER = 1
RED = (255, 0, 0)

steps = 10      # how fast to move

这里是 Sprite1.py:

import pygame
import sys
import os
import time
from pygame import mixer
from pygame.locals import *
from settings import *
vec = pygame.math.Vector2

def showStartScreen(surface):
    show = True
    while (show == True):
        background = pygame.image.load(os.path.join('images', 'Starting_scr.png'))
        # rect = surface.get_rect()
        surface.blit(background, (0,0))
        pygame.display.flip()
        for event in pygame.event.get():
            if event.type == pygame.MOUSEBUTTONDOWN:
                show = False

class Player(pygame.sprite.Sprite):
    def __init__(self, all_sprites):
        self._layer = PLAYER_LAYER
        #self.groups = game.all_sprites
        pygame.sprite.Sprite.__init__(self)
        #self.game = game
        self.movex = 0
        self.movey = 0
        self.frame = 0
        self.health = 10
        self.jumping = False
        self.images = []
        self.imagesleft = []
        self.imagesright = []
        self.direction = "right"
        self.alpha = (0,0,0)
        self.ani = 4 # animation cycles
        self.all_sprites = all_sprites
        self.add(self.all_sprites)
        self.bullet_timer = .1
        self.pos = vec(40, height - 100)
        self.vel = vec(0, 0)
        self.acc = vec(0, 0)

        for i in range(1,5):
            img = pygame.image.load(os.path.join('images','hero' + str(i) + '.png')).convert()
            img.convert_alpha()
            img.set_colorkey(self.alpha)
            self.imagesright.append(img)
            self.image = self.imagesright[0]
            self.rect  = self.image.get_rect()

        for i in range(1,5):
            img = pygame.image.load(os.path.join('images','hero' + str(i) + '.png')).convert()
            img = pygame.transform.flip(img, True, False)
            img.convert_alpha()
            img.set_colorkey(self.alpha)
            self.imagesleft.append(img)
            self.image = self.imagesleft[0]
            self.rect  = self.image.get_rect()

    def control(self,x,y):
        '''
        control player movement
        '''
        self.movex += x
        self.movey -= y

    def jump_cut(self):
        if self.jumping:
            if self.vel.y < -3:
                #self.rect.y += 100
                self.vel.y = -3
                #self.jumping = False
                print(self.vel.y)

    def jump(self):
        # jump only if standing on a platform
        #self.rect.y += 20
        #hits = pygame.sprite.spritecollide(self, self.game.platforms, False)
        #self.rect.y -= 100
        if self.rect.y == 500 and not self.jumping:
            #self.game.jump_sound.play()
            self.jumping = True
            self.vel.y = -PLAYER_JUMP
            print(self.rect.y)

    def update(self, dt):
        '''
        Update sprite position
        '''
        self.rect.x = self.rect.x + self.movex
        self.rect.y = self.rect.y + self.movey

        self.acc = vec(0, PLAYER_GRAV)

        # apply friction
        self.acc.x += self.vel.x * PLAYER_FRICTION
        keys = pygame.key.get_pressed()
        if keys[pygame.K_LEFT]:
            self.acc.x = -PLAYER_ACC
        if keys[pygame.K_RIGHT]:
            self.acc.x = PLAYER_ACC
        # equations of motion
        self.vel += self.acc
        if abs(self.vel.x) < 0.1:
            self.vel.x = 0
        self.pos += self.vel + 0.5 * self.acc
        # wrap around the sides of the screen
        if self.pos.x > width + self.rect.width / 2:
            self.pos.x = 0 - self.rect.width / 2
        if self.pos.x < 0 - self.rect.width / 2:
            self.pos.x = width + self.rect.width / 2

        self.rect.midbottom = self.pos

        # moving left
        if self.movex < 0:
            self.frame += 1
            if self.frame > 3*self.ani:
                self.frame = 0
            self.image = self.imagesleft[self.frame//self.ani]
            self.direction = "left"

        # moving right
        if self.movex > 0:
            self.frame += 1
            if self.frame > 3*self.ani:
                self.frame = 0
            self.image = self.imagesright[self.frame//self.ani]
            self.direction = "right"

        keys = pygame.key.get_pressed()
        if keys[pygame.K_SPACE]:
            self.bullet_timer -= dt  # Subtract the time since the last tick.

        if self.bullet_timer <= 0:
            self.bullet_timer = 100  # Bullet ready.
            if keys:  # Left mouse button.
                # Create a new bullet instance and add it to the groups.
                if self.direction == "right":
                    Bullet([self.rect.x + self.image.get_width(), self.rect.y + self.image.get_height()/2], self.direction, self.all_sprites)
                else:
                    Bullet([self.rect.x, self.rect.y + self.image.get_height()/2], self.direction, self.all_sprites)
                self.bullet_timer = .1  # Reset the timer.



class Bullet(pygame.sprite.Sprite):

    IMAGE = None
    FLIPPED_IMAGE = None

    def __init__(self, pos, direction, *sprite_groups):
        super().__init__(*sprite_groups)

        if not Bullet.IMAGE:
            Bullet.IMAGE = pygame.image.load(os.path.join('images','fireball.png'))
            Bullet.FLIPPED_IMAGE = pygame.transform.flip(Bullet.IMAGE, True, False)

        if direction == "right":
            self.vel = pygame.math.Vector2(750, 0)
            self.image = Bullet.IMAGE
        else:
            self.vel = pygame.math.Vector2(-750, 0)
            self.image = Bullet.FLIPPED_IMAGE

        self.pos = pygame.math.Vector2(pos)
        self.rect  = self.image.get_rect(center=pos)

    def update(self, dt):
        # Add the velocity to the position vector to move the sprite
        self.pos += self.vel * dt
        self.rect.center = self.pos  # Update the rect pos.
        if not pygame.display.get_surface().get_rect().colliderect(self.rect):
            self.kill()

我最终找到了一种方法让它按照我希望的方式工作! 我首先将这些变量写入我的 settings.py:

isJump = False
jumpCount = 10

我在 KEYDOWN 和 KEYUP 之后将这部分代码添加到我的 main.py 主循环中:

    keys = pygame.key.get_pressed()
    if not(isJump):
        if keys[pygame.K_UP]:
            isJump = True
    else:
        if jumpCount >= -10:
            player.rect.y -= (jumpCount * abs(jumpCount)) * 1
            jumpCount -= 2
        else:
            jumpCount = 10
            isJump = False

我在这个网站上学到了所有这些:https://techwithtim.net/tutorials/game-development-with-python/pygame-tutorial/jumping/