Ein Upgrade auswählen

Lektion 15 von 20 im Kurs Pygame-Projekt: Verteidige den Bergfried von Coddy.

Ein Levelaufstieg sollte den Ritter stärker machen, und der Spieler sollte wählen können, wie. Bewahre jede Verbesserung zusammen mit ihrer Wirkung in einem Dictionary auf und biete drei davon nach dem Zufallsprinzip an:

UPGRADES = {
    "Quick bolts": "Bolts fire more often",
    "Sharp bolts": "Bolts hit harder",
    ...
}

self.choices = random.sample(list(UPGRADES), 3)

random.sample(items, 3) wählt drei verschiedene Elemente aus. self.pick ist die Karte, auf der sich der Spieler befindet; Links und Rechts bewegen sie, und % 3 lässt sie im Kreis laufen: rechts von der letzten Karte befindet sich die erste.

Eine Methode wendet eine Verbesserung anhand ihres Namens an, damit die Karten, die Schlüssel und die Wirkung voneinander getrennt bleiben:

def upgrade(self, name):
    knight = self.knight
    if name == "Quick bolts":
        knight.bolt_wait = max(8, knight.bolt_wait - 8)
    elif name == "Sharp bolts":
        knight.bolt_damage += 1
    ...
    self.state = "playing"

Aufgabe

Mittel

Füge UPGRADES hinzu: "Quick bolts", "Sharp bolts", "Spinning axe" (eine weitere Axt kreist um dich), "Swift boots" (du gehst schneller), "Gem magnet" (Edelsteine kommen aus größerer Entfernung) und "Hearty meal" (du erhältst ein Herz zurück), jeweils mit einer kurzen Beschreibung.
Night: choices = [] und pick = 0; beim Levelaufstieg werden drei zufällige choices festgelegt und pick = 1.
Schreibe upgrade(name): Schnelle Bolzen verringern bolt_wait um 8, aber nie unter 8; scharfe Bolzen erhöhen den Schaden um 1; die Axt fügt eine Axt hinzu; die Stiefel erhöhen die Geschwindigkeit um 1; der Magnet erhöht sich um 40; die Mahlzeit fügt 1 Herz hinzu, bis zum Maximum von max_hearts. Danach zurück zu "playing".
In "levelup" ändern Links und Rechts night.pick zyklisch zwischen den drei Karten, und die Leertaste ruft night.upgrade(night.choices[night.pick]) auf.
Zeichne drei Karten mit den Maßen 180 × 120 bei x 60 + i * 210, y 190: den Namen und die Beschreibung jeder Karte, einen 4 Pixel dicken goldenen Rand um die ausgewählte Karte und einen 2 Pixel dicken weißen Rand um die anderen. Darüber steht "Level up! Pick one".

Probier es selbst

import random
import pygame

WIDTH, HEIGHT = 720, 480
TILE = 48
NIGHT = 60 * 60 * 4
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)
GOLD = (250, 200, 60)

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")
gem_sound = sound("coin.ogg")
level_sound = sound("powerup.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))
cover = pygame.Surface((WIDTH, HEIGHT), pygame.SRCALPHA)
cover.fill((0, 0, 0, 150))


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
        self.magnet = 80

    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)

    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


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.xp = 0
        self.level = 1
        self.need = 5
        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 collect(self):
        for gem in pygame.sprite.spritecollide(self.knight, self.gems, True):
            self.xp += 1
            gem_sound.play()
        if self.xp >= self.need:
            self.xp -= self.need
            self.level += 1
            self.need += 4
            self.state = "levelup"
            level_sound.play()

    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.gems.update(self.knight)
        self.shoot()
        self.hurt_monsters()
        self.collect()
        self.take_hits()


night = Night()

running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        elif event.type == pygame.KEYDOWN:
            if night.state == "levelup":
                if event.key == pygame.K_SPACE:
                    night.state = "playing"

    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)))
    label = font.render(f"Level {night.level}", True, WHITE)
    screen.blit(label, label.get_rect(topright=(WIDTH - 10, 4)))
    pygame.draw.rect(screen, (40, 40, 60), (WIDTH - 160, 30, 150, 10))
    pygame.draw.rect(screen, GOLD, (WIDTH - 160, 30, 150 * night.xp // night.need, 10))
    if night.state == "levelup":
        screen.blit(cover, (0, 0))
        title = big_font.render("Level up!", True, GOLD)
        screen.blit(title, title.get_rect(center=(WIDTH // 2, 200)))
        hint = font.render("Press Space to keep going", True, WHITE)
        screen.blit(hint, hint.get_rect(center=(WIDTH // 2, 260)))
    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()