行走动画循环

Question

我创建了一条向玩家移动的龙，并且在这样做的同时它有一个飞行的动画。但是，如果玩家站在与龙的特定角度，则飞行动画会停止，直到它直接位于玩家上方/侧面，或立即对角线。

例如，站在龙的下方会触发动画，但站在下方并向右上方会导致龙的动画暂停，直到它立即变成对角线。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()

这是我用来简化代码运行的精灵表

Answer 1

除了ZeroDivisionError Azhy 已经指出的，你的问题是你通过将posx/posy 乘以一个常数来计算动画的当前图像。

所以如果posy不改变，图片就不会改变。

你可以打印出update末尾的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根据当前位置更改图像。