python - 行走动画循环

Question

我创建了一条向玩家移动的龙，并且在这样做时它有一个飞翔的动画。然而，如果玩家站在龙的特定角度，飞行动画会停止，直到它直接位于玩家上方/侧面，或紧靠对角线。

例如，站在龙的下方会触发动画，但站在龙的下方和右侧会导致龙动画暂停，直到它立即对角线。这是一个完全可运行的示例；

主游戏

from Rooms import *
from Player import *
import pygame


BLACK = (0, 0, 0)
WHITE = (255, 255, 255)


pygame.init()

screen_width = 1080
screen_height = 607
screen = pygame.display.set_mode([screen_width, screen_height])

pygame.display.set_caption('Labyrinth')

block_list = pygame.sprite.Group()
all_sprites_list = pygame.sprite.Group()

rooms = []

room = Room0()
rooms.append(room)

current_room_no = 0
current_room = rooms[current_room_no]

player = Player("Isaac.png", 420, 150, current_room)
all_sprites_list.add(player)


clock = pygame.time.Clock()


done = False


# -- MAIN PROGRAM LOOP -- #

# -- Event processing --

while not done:

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            done = True


# Player controls

        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                player.changespeed(-7, 0)
            elif event.key == pygame.K_RIGHT:
                player.changespeed(7, 0)
            elif event.key == pygame.K_UP:
                player.changespeed(0, -7)
            elif event.key == pygame.K_DOWN:
                player.changespeed(0, 7)

        elif event.type == pygame.KEYUP:
            if event.key == pygame.K_LEFT:
                player.changespeed(7, 0)
            elif event.key == pygame.K_RIGHT:
                player.changespeed(-7, 0)
            elif event.key == pygame.K_UP:
                player.changespeed(0, 7)
            elif event.key == pygame.K_DOWN:
                player.changespeed(0, -7)

# -- Game Logic --

    all_sprites_list.update()
    current_room.enemy_sprites.update(player)

# Hit detection 

    screen.blit(current_room.background_image, current_room.background_position)

    all_sprites_list.draw(screen)
    current_room.enemy_sprites.draw(screen)


    pygame.display.flip()

    clock.tick(60)

pygame.quit()

龙类

import pygame
import math
from Player import Player
import time

BLACK = (0, 0, 0)

class SpriteSheet(object):

    def __init__(self, file_name):

        self.sprite_sheet = pygame.image.load(file_name).convert()


    def get_image(self, x, y, width, height):

        image = pygame.Surface([width, height]).convert()
        image.blit(self.sprite_sheet, (0, 0), (x, y, width, height))
        image.set_colorkey(BLACK)

        return image


class Dragon(pygame.sprite.Sprite):

    def __init__(self, x, y):

        super().__init__()

        self.flying_frames_l = []
        self.flying_frames_r = []

        sprite_sheet = SpriteSheet("Dragon.png")

# Flying left
        image = sprite_sheet.get_image(12, 22, 95, 85)
        self.flying_frames_l.append(image)
        image = sprite_sheet.get_image(140, 35, 95, 67)
        self.flying_frames_l.append(image)
        image = sprite_sheet.get_image(18, 138, 96, 55)
        self.flying_frames_l.append(image)
        image = sprite_sheet.get_image(128, 131, 96, 63)
        self.flying_frames_l.append(image)
        image = sprite_sheet.get_image(140, 35, 95, 67)
        self.flying_frames_l.append(image)
        image = sprite_sheet.get_image(12, 22, 95, 85)
        self.flying_frames_l.append(image)

# Flying right
        image = sprite_sheet.get_image(12, 22, 95, 85)
        image = pygame.transform.flip(image, True, False)
        self.flying_frames_r.append(image)
        image = sprite_sheet.get_image(140, 35, 95, 67)
        image = pygame.transform.flip(image, True, False)
        self.flying_frames_r.append(image)
        image = sprite_sheet.get_image(18, 138, 96, 55)
        image = pygame.transform.flip(image, True, False)
        self.flying_frames_r.append(image)
        image = sprite_sheet.get_image(128, 131, 96, 63)
        image = pygame.transform.flip(image, True, False)
        self.flying_frames_r.append(image)
        image = sprite_sheet.get_image(140, 35, 95, 67)
        image = pygame.transform.flip(image, True, False)
        self.flying_frames_r.append(image)
        image = sprite_sheet.get_image(12, 22, 95, 85)
        image = pygame.transform.flip(image, True, False)
        self.flying_frames_r.append(image)


        self.image = self.flying_frames_r[0]
        self.rect = self.image.get_rect()
        self.rect.y = y
        self.rect.x = x

        self.speedx = 0
        self.speedy = 0

        self.health = 100


    def update(self, player):

        posx = self.rect.x
        posy = self.rect.y

        dx = self.rect.x - player.rect.x
        dy = self.rect.y - player.rect.y

        dist = math.hypot(dx, dy)

        dx = dx / dist
        dy = dy / dist

        if dx > 0:
            self.speedx = -1.5

        if dx <= 0:
            self.speedx = -1.5          

        if dy >= 0:
            self.speedy = -1.5

        if dy <= 0:
            self.speedy = -1.5


        self.rect.x += dx * self.speedx
        self.rect.y += dy * self.speedy


        if self.rect.x < player.rect.x:
            frame = (posx // 10) % len(self.flying_frames_l)
            self.image = self.flying_frames_l[frame]
        else:
            frame = (posx // 10) % len(self.flying_frames_r)
            self.image = self.flying_frames_r[frame]

        if self.rect.y < player.rect.y:
            frame = (posy // 10) % len(self.flying_frames_l)
            self.image = self.flying_frames_l[frame]
        else:
            frame = (posy // 10) % len(self.flying_frames_r)
            self.image = self.flying_frames_r[frame]

播放器类

import pygame


BLACK = (0, 0, 0)
WHITE = (255, 255, 255)


class Player(pygame.sprite.Sprite):


    def __init__(self, filename, x, y, current_room):

        super().__init__()

        self.image = pygame.image.load(filename).convert()
        self.image.set_colorkey(BLACK)

        self.rect = self.image.get_rect()
        self.rect.x = x
        self.rect.y = y

        self.change_x = 0
        self.change_y = 0

    def changespeed(self, x, y):
        self.change_x += x
        self.change_y += y

    def update(self):
        self.rect.x += self.change_x
        self.rect.y += self.change_y

房间等级

import Player
import pygame
from Enemies import Dragon


class Room(object):
    enemy_sprites = None

    def __init__(self):
        self.enemy_sprites = pygame.sprite.Group()


class Room0(Room):
    def __init__(self):
        super().__init__()

        enemy = Dragon(380, 280)
        self.enemy_sprites.add(enemy)

        self.background_position = [0, 0]
        self.background_image = pygame.image.load("Floor.png").convert()

这是我用来使运行代码更容易的 spritesheet

Answer 1

除了 Azhy 已经指出的 ZeroDivisionError 之外，您的问题是您通过将 posx/posy 潜水来计算动画的当前图像一个常数。

所以如果posy不改变，图像就不会改变。

可以在update的最后打印出frame自己看。

---

您可以将动画处理提取到它自己的类或其他东西中，这是一个简单的示例:

class Animation(object):
    def __init__(self, sprite, speed, images):
        self.sprite = sprite
        self.images = images
        self.speed = speed
        self.step = 0
        self.frame = 0

    def update(self):
        self.step += 1
        if self.step >= self.speed:
            self.frame = (self.frame + 1) % len(self.images)
            self.sprite.image = self.images[self.frame]
            self.step = 0

然后 Dragon 类可能如下所示:

class Dragon(pygame.sprite.Sprite):

    def __init__(self, x, y):

        super().__init__()

        flying_frames_l = []
        flying_frames_r = []

        sprite_sheet = SpriteSheet("Dragon.png")

# Flying left
        image = sprite_sheet.get_image(12, 22, 95, 85)
        flying_frames_l.append(image)
        image = sprite_sheet.get_image(140, 35, 95, 67)
        flying_frames_l.append(image)
        image = sprite_sheet.get_image(18, 138, 96, 55)
        flying_frames_l.append(image)
        image = sprite_sheet.get_image(128, 131, 96, 63)
        flying_frames_l.append(image)
        image = sprite_sheet.get_image(140, 35, 95, 67)
        flying_frames_l.append(image)
        image = sprite_sheet.get_image(12, 22, 95, 85)
        flying_frames_l.append(image)
        self.flying_left = Animation(self, 6, flying_frames_l)

# Flying right
        image = sprite_sheet.get_image(12, 22, 95, 85)
        image = pygame.transform.flip(image, True, False)
        flying_frames_r.append(image)
        image = sprite_sheet.get_image(140, 35, 95, 67)
        image = pygame.transform.flip(image, True, False)
        flying_frames_r.append(image)
        image = sprite_sheet.get_image(18, 138, 96, 55)
        image = pygame.transform.flip(image, True, False)
        flying_frames_r.append(image)
        image = sprite_sheet.get_image(128, 131, 96, 63)
        image = pygame.transform.flip(image, True, False)
        flying_frames_r.append(image)
        image = sprite_sheet.get_image(140, 35, 95, 67)
        image = pygame.transform.flip(image, True, False)
        flying_frames_r.append(image)
        image = sprite_sheet.get_image(12, 22, 95, 85)
        image = pygame.transform.flip(image, True, False)
        flying_frames_r.append(image)
        self.flying_right = Animation(self, 6, flying_frames_r)

        self.image = flying_frames_r[0]
        self.rect = self.image.get_rect()
        self.rect.y = y
        self.rect.x = x

        self.speedx = 0
        self.speedy = 0

        self.health = 100
        self.animation = self.flying_right

    def update(self, player):

        posx = self.rect.x
        posy = self.rect.y

        dx = self.rect.x - player.rect.x
        dy = self.rect.y - player.rect.y

        dist = math.hypot(dx, dy)

        if dist > 0:
            dx = dx / dist
            dy = dy / dist

        if dx > 0:
            self.speedx = -1.5
            self.animation = self.flying_left

        if dx <= 0:
            self.speedx = -1.5          
            self.animation = self.flying_right

        if dy >= 0:
            self.speedy = -1.5

        if dy <= 0:
            self.speedy = -1.5


        self.rect.x += dx * self.speedx
        self.rect.y += dy * self.speedy


        self.animation.update()

请注意我们如何简单地增加一个计数器来查看我们是否应该改变图像而不是依赖于当前位置。