Siklus Berjalan

Termasuk bagian Dunia Game dalam perjalanan Pygame di Coddy. Pelajaran 26 dari 35.

Blob yang meluncur dengan satu gambar terlihat membeku. Paketnya memiliki pose kedua, blob_walk.png, dengan posisi kaki yang berbeda. Menampilkan keduanya secara bergantian membuatnya berjalan.

Simpan kedua pose dalam sebuah list dan penghitung frame di dalam sprite. Pada setiap pembaruan, hitung naik lalu pilih pose berdasarkan hitungan:

self.frames = [blob_img, blob_walk_img]
self.timer = 0
# di update
self.timer += 1
self.image = self.frames[self.timer // 10 % 2]

self.timer // 10 bertambah satu setiap 10 frame, dan % 2 mengubahnya menjadi 0, 1, 0, 1. Setiap pose ditampilkan selama 10 frame, enam langkah per detik. Angka yang lebih kecil dari 10 membuat kaki bergerak lebih cepat.

Perulangan penggambaran sudah melakukan blit pada blob.image, jadi cukup ubah self.image.

Tantangan

Mudah

Di Blob.__init__, buat self.frames = [blob_img, blob_walk_img] dan self.timer = 0 (blob_walk_img dimuat di kode awal).
Di awal update, tambahkan 1 ke self.timer dan atur self.image = self.frames[self.timer // 10 % 2].

Coba sendiri

import pygame

TILE = 36
SPEED = 4
GRAVITY = 1
JUMP = -15
MAX_FALL = 12

LEVEL = [
    "................",
    "................",
    "................",
    "................",
    "..........####..",
    "................",
    "...####.........",
    "................",
    "#.P............#",
    "################",
]

pygame.init()
screen = pygame.display.set_mode((576, 360))
pygame.display.set_caption("Walk Cycle")
clock = pygame.time.Clock()

background = pygame.image.load("assets/backgrounds/clouds.png").convert_alpha()
block_img = pygame.image.load("assets/images/block.png").convert_alpha()
player_img = pygame.image.load("assets/images/player.png").convert_alpha()
blob_img = pygame.image.load("assets/images/blob.png").convert_alpha()
blob_walk_img = pygame.image.load("assets/images/blob_walk.png").convert_alpha()


class Blob(pygame.sprite.Sprite):
    def __init__(self, midbottom):
        super().__init__()
        self.image = blob_img
        self.rect = pygame.Rect(0, 0, 30, 26)
        self.rect.midbottom = midbottom
        self.direction = 1

    def update(self):
        self.rect.x += self.direction
        if self.direction > 0:
            ahead = self.rect.right
        else:
            ahead = self.rect.left - 1
        hit_wall = any(self.rect.colliderect(wall) for wall in walls)
        ground_ahead = any(wall.collidepoint(ahead, self.rect.bottom) for wall in walls)
        if hit_wall or not ground_ahead:
            self.rect.x -= self.direction
            self.direction = -self.direction

walls = []
for row, line in enumerate(LEVEL):
    for col, char in enumerate(line):
        if char == "#":
            walls.append(pygame.Rect(col * TILE, row * TILE, TILE, TILE))
        elif char == "P":
            start = (col * TILE + TILE // 2, row * TILE + TILE)

blobs = pygame.sprite.Group(Blob((432, 144)), Blob((432, 324)))
player = player_img.get_rect(midbottom=start)
vel_y = 0
on_ground = False

running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        elif event.type == pygame.KEYDOWN and event.key in (pygame.K_SPACE, pygame.K_UP):
            if on_ground:
                vel_y = JUMP
        elif event.type == pygame.KEYUP and event.key in (pygame.K_SPACE, pygame.K_UP):
            if vel_y < -4:
                vel_y = -4

    keys = pygame.key.get_pressed()
    dx = 0
    if keys[pygame.K_LEFT]:
        dx -= SPEED
    if keys[pygame.K_RIGHT]:
        dx += SPEED

    player.x += dx
    for wall in walls:
        if player.colliderect(wall):
            if dx > 0:
                player.right = wall.left
            elif dx < 0:
                player.left = wall.right

    vel_y = min(vel_y + GRAVITY, MAX_FALL)
    player.y += vel_y
    on_ground = False
    for wall in walls:
        if player.colliderect(wall):
            if vel_y > 0:
                player.bottom = wall.top
                on_ground = True
            elif vel_y < 0:
                player.top = wall.bottom
            vel_y = 0

    blobs.update()

    for blob in blobs:
        if player.colliderect(blob.rect):
            if vel_y > 0 and player.bottom < blob.rect.centery:
                blob.kill()
                vel_y = -8
            else:
                player.midbottom = start
                vel_y = 0

    for y in range(0, 360, 72):
        for x in range(0, 576, 72):
            screen.blit(background, (x, y))
    for wall in walls:
        screen.blit(block_img, wall)
    for blob in blobs:
        screen.blit(blob.image, blob.image.get_rect(midbottom=blob.rect.midbottom))
    screen.blit(player_img, player)
    pygame.display.flip()
    clock.tick(60)

pygame.quit()