Load It at the Start

Part of the Game Rules section of Coddy's Pygame journey. Lesson 21 of 29.

The record is saved; now read it back when the game starts. int(file.read()) turns the file's text into a number. The very first time there is no file, and open stops the program with FileNotFoundError.

try and except catch that error and do something else instead:

def load_best():
    try:
        with open("highscore.txt") as file:
            return int(file.read())
    except FileNotFoundError:
        return 0


best = load_best()

Python runs the try block. If open raises FileNotFoundError, it jumps to the except block and returns 0. Any other error still stops the program, which is what you want: it is a real bug.

open("highscore.txt") with no mode opens the file for reading.

On a desktop, close the game, run it again, and the best from last time shows on the first game over screen. In the browser the same happens each time you press Play, until the page reloads.

Challenge

Medium

Write load_best(): it returns the number in highscore.txt, or 0 when there is no such file.
Set best = load_best() instead of best = 0.

Try it yourself

import random
import pygame

pygame.init()
screen = pygame.display.set_mode((480, 360))
pygame.display.set_caption("Meteor Dodge")
clock = pygame.time.Clock()
heart = pygame.image.load("assets/images/heart.png").convert_alpha()
heart_empty = pygame.image.load("assets/images/heart_empty.png").convert_alpha()
font = pygame.font.Font("assets/fonts/pixel.ttf", 24)
big_font = pygame.font.Font("assets/fonts/pixel.ttf", 48)
WHITE = (240, 240, 240)
PLATE = (60, 60, 90)
POINT = pygame.USEREVENT + 1
SPAWN = pygame.USEREVENT + 2


def reset():
    global player, rocks, score, lives
    player = pygame.Rect(220, 300, 40, 40)
    rocks = []
    score = 0
    lives = 3
    pygame.time.set_timer(POINT, 1000)
    pygame.time.set_timer(SPAWN, 800)


def draw_menu():
    screen.fill((30, 30, 46))
    title = big_font.render("Meteor Dodge", True, WHITE)
    title_rect = title.get_rect(center=(240, 140))
    pygame.draw.rect(screen, PLATE, title_rect.inflate(24, 12))
    screen.blit(title, title_rect)
    hint = font.render("Press Enter to play", True, WHITE)
    screen.blit(hint, hint.get_rect(center=(240, 200)))


def draw_game():
    screen.fill((30, 30, 46))
    pygame.draw.rect(screen, (255, 196, 0), player)
    for rock in rocks:
        pygame.draw.rect(screen, (235, 80, 80), rock)
    score_text = font.render(f"{score:05}", True, WHITE)
    score_rect = score_text.get_rect(topright=(470, 10))
    pygame.draw.rect(screen, PLATE, score_rect.inflate(12, 8))
    screen.blit(score_text, score_rect)
    for i in range(3):
        if i < lives:
            screen.blit(heart, (10 + i * 40, 10))
        else:
            screen.blit(heart_empty, (10 + i * 40, 10))


def play_frame():
    global rocks, lives, state, best
    keys = pygame.key.get_pressed()
    if keys[pygame.K_LEFT]:
        player.x -= 6
    if keys[pygame.K_RIGHT]:
        player.x += 6
    player.clamp_ip(screen.get_rect())

    kept = []
    for rock in rocks:
        rock.y += 3
        if rock.colliderect(player):
            lives -= 1
        elif rock.top <= 360:
            kept.append(rock)
    rocks = kept
    if lives <= 0:
        state = "over"
        best = max(best, score)
        with open("highscore.txt", "w") as file:
            file.write(str(best))
    draw_game()


def draw_over():
    draw_game()
    message = big_font.render("Game over", True, WHITE)
    screen.blit(message, message.get_rect(center=(240, 160)))
    hint = font.render("Press R to play again", True, WHITE)
    screen.blit(hint, hint.get_rect(center=(240, 200)))
    best_text = font.render(f"Best: {best}", True, WHITE)
    screen.blit(best_text, best_text.get_rect(center=(240, 240)))


reset()
state = "menu"
best = 0

running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        if event.type == POINT and state == "play":
            score += 1
        if event.type == SPAWN and state == "play":
            rocks.append(pygame.Rect(random.randint(0, 456), -24, 24, 24))
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_RETURN and state == "menu":
                reset()
                state = "play"
            elif event.key == pygame.K_r and state == "over":
                reset()
                state = "play"

    if state == "menu":
        draw_menu()
    elif state == "play":
        play_frame()
    else:
        draw_over()
    pygame.display.flip()
    clock.tick(60)

pygame.quit()