Aimant à gemmes

Leçon 16 sur 25 du cours Projet Pygame : Défendez le donjon de Coddy.

Les gemmes proches du chevalier volent vers lui, de sorte que le joueur n'a pas besoin de marcher sur chacune d'elles. move_towards_ip(target, d) déplace un Vector2 de jusqu'à d pixels vers un point, sans jamais le dépasser :

def update(self, knight):
    target = pygame.Vector2(knight.rect.center)
    if self.pos.distance_to(target) < knight.magnet:
        self.pos.move_towards_ip(target, 6)
    self.rect.center = self.pos

La distance à laquelle les gemmes commencent à voler est définie par magnet du chevalier, soit 80 pixels au départ ; une amélioration l'augmentera.

spritecollide(sprite, group, True) renvoie chaque sprite du groupe qui entre en contact, et True les retire aussi du groupe : une seule ligne ramasse toutes les gemmes sur lesquelles le chevalier marche.

Défi

Moyen

Les gemmes proches du chevalier volent vers lui et sont ramassées.

Donne au chevalier magnet = 80 et à Gem le update ci-dessus.
Charge gem_sound = sound("coin.ogg"). Donne à Night xp = 0 et collect(self) : chaque gemme touchée par le chevalier est supprimée, rapporte 1 xp et déclenche gem_sound.
Dans update : self.gems.update(self.knight) après le déplacement des projectiles, self.collect() après hurt_monsters.

Appuie sur « Jouer » et marche près d’une gemme : elle vole vers toi avec un son de pièce. Puis appuie sur « Vérifier ».

Essayez vous-même

import random
import pygame

WIDTH, HEIGHT = 720, 480
TILE = 48
NIGHT = 60 * 60 * 4
# Les types de monstres envoyés par chaque vague, de la première à la dernière
WAVES = [
    ["slime"],
    ["slime", "bat"],
    ["slime", "bat", "spider"],
    ["bat", "spider"],
    ["slime", "spider", "ghost"],
    ["bat", "spider", "ghost"],
    ["spider", "ghost"],
    ["bat", "ghost"],
]
WHITE = (240, 240, 240)
BOLT = (120, 200, 255)

pygame.init()
screen = pygame.display.set_mode((WIDTH, HEIGHT))
pygame.display.set_caption("Hold the Keep")
clock = pygame.time.Clock()
font = pygame.font.Font("assets/fonts/pixel.ttf", 24)
big_font = pygame.font.Font("assets/fonts/pixel.ttf", 48)


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


def sound(name):
    return pygame.mixer.Sound("assets/sounds/" + name)


def whiten(image):
    white = image.copy()
    white.fill((255, 255, 255), special_flags=pygame.BLEND_RGB_MAX)
    return white


floor_img = load("floor.png")
wall_img = load("wall.png")
knight_img = load("knight.png")
axe_img = load("axe.png")
gem_img = load("gem.png")
heart_img = load("heart.png")
empty_img = load("heart_empty.png")
MONSTERS = {
    "slime": {"image": load("slime.png"), "speed": 1.0, "hp": 1},
    "bat": {"image": load("dungeon_bat.png"), "speed": 1.6, "hp": 1},
    "spider": {"image": load("spider.png"), "speed": 1.2, "hp": 3},
    "ghost": {"image": load("ghost.png"), "speed": 0.8, "hp": 4},
}
hit_sound = sound("hit.ogg")
hurt_sound = sound("thud.ogg")

courtyard = pygame.Rect(TILE, TILE, WIDTH - 2 * TILE, HEIGHT - 2 * TILE)
background = pygame.Surface((WIDTH, HEIGHT))
for row in range(HEIGHT // TILE):
    for col in range(WIDTH // TILE):
        x = col * TILE
        y = row * TILE
        if courtyard.collidepoint(x, y):
            background.blit(floor_img, (x, y))
        else:
            background.blit(wall_img, (x, y))


def draw(image, center):
    screen.blit(image, image.get_rect(center=center))


def clock_text(frames):
    seconds = frames // 60
    return f"{seconds // 60}:{seconds % 60:02d}"


def edge_point():
    side = random.randint(0, 3)
    if side == 0:
        return (random.randint(0, WIDTH), -24)
    if side == 1:
        return (random.randint(0, WIDTH), HEIGHT + 24)
    if side == 2:
        return (-24, random.randint(0, HEIGHT))
    return (WIDTH + 24, random.randint(0, HEIGHT))


class Knight(pygame.sprite.Sprite):
    def __init__(self):
        super().__init__()
        self.image = knight_img
        self.rect = pygame.Rect(0, 0, 24, 24)
        self.rect.center = courtyard.center
        self.speed = 3
        self.hearts = 5
        self.max_hearts = 5
        self.hurt = 0
        self.bolt_wait = 30
        self.bolt_damage = 1
        self.axes = 1

    def move(self, keys):
        if keys[pygame.K_LEFT]:
            self.rect.x -= self.speed
        if keys[pygame.K_RIGHT]:
            self.rect.x += self.speed
        if keys[pygame.K_UP]:
            self.rect.y -= self.speed
        if keys[pygame.K_DOWN]:
            self.rect.y += self.speed
        self.rect.clamp_ip(courtyard)


class Monster(pygame.sprite.Sprite):
    def __init__(self, kind, pos):
        super().__init__()
        self.kind = kind
        self.image = MONSTERS[kind]["image"]
        self.speed = MONSTERS[kind]["speed"]
        self.hp = MONSTERS[kind]["hp"]
        self.axe_wait = 0
        self.flash = 0
        self.pos = pygame.Vector2(pos)
        self.rect = pygame.Rect(0, 0, 28, 28)
        self.rect.center = self.pos

    def update(self, target):
        step = pygame.Vector2(target) - self.pos
        if step.length() > 0:
            self.pos += step.normalize() * self.speed
        self.rect.center = self.pos
        if self.axe_wait > 0:
            self.axe_wait -= 1
        if self.flash > 0:
            self.flash -= 1

    def hit(self, damage):
        self.hp -= damage
        self.flash = 6
        hit_sound.play()


class Bolt(pygame.sprite.Sprite):
    def __init__(self, start, target, damage):
        super().__init__()
        self.pos = pygame.Vector2(start)
        step = pygame.Vector2(target) - self.pos
        if step.length() == 0:
            step = pygame.Vector2(1, 0)
        self.velocity = step.normalize() * 7
        self.damage = damage
        self.rect = pygame.Rect(0, 0, 10, 10)
        self.rect.center = self.pos

    def update(self):
        self.pos += self.velocity
        self.rect.center = self.pos
        if not screen.get_rect().colliderect(self.rect):
            self.kill()


class Gem(pygame.sprite.Sprite):
    def __init__(self, pos):
        super().__init__()
        self.rect = pygame.Rect(0, 0, 24, 24)
        self.rect.center = pos
        self.rect.clamp_ip(courtyard)
        self.pos = pygame.Vector2(self.rect.center)


class Night:
    def __init__(self):
        self.knight = Knight()
        self.time = 0
        self.monsters = pygame.sprite.Group()
        self.bolts = pygame.sprite.Group()
        self.bolt_timer = 0
        self.spin = 0
        self.gems = pygame.sprite.Group()
        self.state = "playing"

    def wave(self):
        return min(len(WAVES), self.time * len(WAVES) // NIGHT + 1)

    def spawn(self):
        wave = self.wave()
        if self.time % max(16, 46 - wave * 5) == 0:
            kind = random.choice(WAVES[wave - 1])
            self.monsters.add(Monster(kind, edge_point()))

    def nearest(self):
        point = pygame.Vector2(self.knight.rect.center)
        best = None
        for monster in self.monsters:
            if best is None or point.distance_to(monster.pos) < point.distance_to(best.pos):
                best = monster
        return best

    def shoot(self):
        self.bolt_timer += 1
        target = self.nearest()
        if self.bolt_timer >= self.knight.bolt_wait and target is not None:
            self.bolt_timer = 0
            bolt = Bolt(self.knight.rect.center, target.pos, self.knight.bolt_damage)
            self.bolts.add(bolt)

    def axe_spots(self):
        spots = []
        for i in range(self.knight.axes):
            angle = self.spin + i * 360 / self.knight.axes
            offset = pygame.Vector2(70, 0).rotate(angle)
            spots.append(pygame.Vector2(self.knight.rect.center) + offset)
        return spots

    def hurt_monsters(self):
        for bolt in self.bolts:
            target = pygame.sprite.spritecollideany(bolt, self.monsters)
            if target is not None:
                target.hit(bolt.damage)
                bolt.kill()
        for spot in self.axe_spots():
            blade = pygame.Rect(0, 0, 36, 36)
            blade.center = spot
            for monster in self.monsters:
                if monster.axe_wait == 0 and blade.colliderect(monster.rect):
                    monster.hit(1)
                    monster.axe_wait = 20
        for monster in list(self.monsters):
            if monster.hp <= 0:
                monster.kill()
                self.gems.add(Gem(monster.pos))

    def take_hits(self):
        knight = self.knight
        if knight.hurt > 0:
            knight.hurt -= 1
        elif pygame.sprite.spritecollideany(knight, self.monsters):
            knight.hearts -= 1
            knight.hurt = 75
            hurt_sound.play()
            if knight.hearts <= 0:
                self.state = "lost"

    def update(self, keys):
        self.time += 1
        self.spin = (self.spin + 4) % 360
        self.knight.move(keys)
        self.spawn()
        self.monsters.update(self.knight.rect.center)
        self.bolts.update()
        self.shoot()
        self.hurt_monsters()
        self.take_hits()


night = Night()

running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

    if night.state == "playing":
        night.update(pygame.key.get_pressed())

    screen.blit(background, (0, 0))
    knight = night.knight
    for gem in night.gems:
        draw(gem_img, gem.rect.center)
    for monster in night.monsters:
        if monster.flash > 0:
            draw(whiten(monster.image), monster.rect.center)
        else:
            draw(monster.image, monster.rect.center)
    if knight.hurt % 10 < 5:
        draw(knight.image, knight.rect.center)
    for spot in night.axe_spots():
        draw(pygame.transform.rotate(axe_img, -night.spin * 3), spot)
    for bolt in night.bolts:
        pygame.draw.circle(screen, BOLT, bolt.rect.center, 5)
    for i in range(knight.max_hearts):
        if i < knight.hearts:
            screen.blit(heart_img, (8 + i * 34, 6))
        else:
            screen.blit(empty_img, (8 + i * 34, 6))
    left = font.render(clock_text(max(0, NIGHT - night.time)) + " until dawn", True, WHITE)
    screen.blit(left, left.get_rect(center=(WIDTH // 2, 24)))
    if night.state == "lost":
        message = big_font.render("The keep has fallen", True, WHITE)
        screen.blit(message, message.get_rect(center=(WIDTH // 2, 200)))
    pygame.display.flip()
    clock.tick(60)

pygame.quit()