Blobs en las cuevas

Parte de la sección Mundos del Journey de Pygame de Coddy. Lección 33 de 35.

Dos blobs patrullan el suelo de la cueva. Incorpora la clase Blob de Enemies That Patrol, con su ciclo de caminata: gira al llegar a paredes y salientes y muestra sus dos poses alternativamente.

Cada E en el mapa añade un blob de pie sobre esa casilla. En cada fotograma, actualiza el grupo y después comprueba cada blob contra el jugador. Un pisotón elimina el blob y hace rebotar al jugador; cualquier otro contacto es peligroso, así que establece hurt, como con un pincho:

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:
            hurt = True

Dibuja cada blob a través de la cámara, con la parte inferior central de su imagen alineada con la parte inferior central de su Rect:

spot = blob.image.get_rect(midbottom=(blob.rect.centerx - camera_x, blob.rect.bottom))
screen.blit(blob.image, spot)

Desafío

Difícil

Carga blob.png y blob_walk.png en blob_img y blob_walk_img, y añade la clase Blob con su ciclo de patrulla y caminata, después de solid().
Crea blobs = pygame.sprite.Group() antes del bucle del mapa y añade un Blob(rect.midbottom) por cada E.
En cada fotograma, después de las púas, actualiza blobs y aplasta al enemigo o establece hurt, como se muestra.
Dibuja los enemigos después de las púas.

Pruébalo tú mismo

import pygame

TILE = 36
WIDTH, HEIGHT = 576, 360
SPEED = 4
GRAVITY = 1
JUMP = -15
MAX_FALL = 12

LEVEL = [
    "................................................................",
    "................................................................",
    "................................................................",
    "................................................................",
    "#..............................................................#",
    "#....................C.........................#####...........#",
    "#......CC...C................CC.....CC.........#####.....CC....#",
    "#....................#.........................D...............#",
    "#.P.........#...E....#...^.......K......E......D.C....^......F.#",
    "#######..####################..##########################..#####",
]

pygame.init()
screen = pygame.display.set_mode((WIDTH, HEIGHT))
pygame.display.set_caption("Moss Caves")
clock = pygame.time.Clock()
font = pygame.font.Font("assets/fonts/pixel.ttf", 24)


def load(name):
    return pygame.image.load("assets/images/" + name).convert_alpha()


background = pygame.image.load("assets/backgrounds/forest.png").convert_alpha()
grass_img = load("grass.png")
grass_left_img = load("grass_left.png")
grass_right_img = load("grass_right.png")
dirt_img = load("dirt.png")
player_img = load("player.png")
coin_img = load("coin.png")
spikes_img = load("spikes.png")
heart_img = load("heart.png")
heart_empty_img = load("heart_empty.png")


def solid(row, col):
    if row < 0 or row >= len(LEVEL) or col < 0 or col >= len(LEVEL[0]):
        return False
    return LEVEL[row][col] == "#"


walls = []
tiles = []
coins = []
spikes = []
for row, line in enumerate(LEVEL):
    for col, char in enumerate(line):
        rect = pygame.Rect(col * TILE, row * TILE, TILE, TILE)
        if char == "#":
            if solid(row - 1, col):
                image = dirt_img
            elif not solid(row, col - 1) and solid(row, col + 1):
                image = grass_left_img
            elif solid(row, col - 1) and not solid(row, col + 1):
                image = grass_right_img
            else:
                image = grass_img
            walls.append(rect)
            tiles.append((image, rect))
        elif char == "P":
            start = rect.midbottom
        elif char == "C":
            coins.append(rect)
        elif char == "^":
            spikes.append(pygame.Rect(rect.x, rect.y + 18, TILE, 18))

level_width = len(LEVEL[0]) * TILE
player = player_img.get_rect(midbottom=start)
vel_y = 0
on_ground = False
camera_x = 0
coins_collected = 0
lives = 3

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

    hurt = False
    if player.top > HEIGHT:
        hurt = True

    for coin in coins[:]:
        if player.colliderect(coin):
            coins.remove(coin)
            coins_collected += 1
    for spike in spikes:
        if player.colliderect(spike):
            hurt = True

    if hurt:
        lives -= 1
        player.midbottom = start
        vel_y = 0

    camera_x = player.centerx - WIDTH // 2
    camera_x = max(0, min(camera_x, level_width - WIDTH))

    shift = camera_x // 3 % 72
    for y in range(0, HEIGHT, 72):
        for x in range(-shift, WIDTH, 72):
            screen.blit(background, (x, y))
    for image, rect in tiles:
        screen.blit(image, (rect.x - camera_x, rect.y))
    for coin in coins:
        screen.blit(coin_img, (coin.x - camera_x, coin.y))
    for spike in spikes:
        screen.blit(spikes_img, (spike.x - camera_x, spike.y - 18))
    screen.blit(player_img, (player.x - camera_x, player.y))
    for i in range(3):
        if i < lives:
            screen.blit(heart_img, (10 + i * 40, 8))
        else:
            screen.blit(heart_empty_img, (10 + i * 40, 8))
    text = font.render(f"Coins: {coins_collected}", True, (255, 255, 255))
    screen.blit(text, text.get_rect(topright=(WIDTH - 12, 14)))
    pygame.display.flip()
    clock.tick(60)

pygame.quit()