Eat and Grow

Part of the Projects section of Coddy's Pygame journey. Lesson 7 of 31.

When the new head lands on the food, the snake eats it. Growing is the move you already have, minus one line: on a step that eats, skip the pop, and the tail stays.

body.insert(0, (x, y))
if (x, y) == food:
    score += 1
    food = new_food(body)
else:
    body.pop()

Tuples compare item by item, so (x, y) == food is true when both the column and the row match.

Show the score the way you have before: a font made before the loop, and f"Score: {score}" rendered each frame at (8, 6).

Challenge

Medium

Before the loop make font = pygame.font.Font(None, 32) and score = 0.
After inserting the new head: if it is on the food, add 1 to the score and place new food; otherwise pop the tail.
Render f"Score: {score}" in (240, 240, 240) and blit it at (8, 6).

Try it yourself

import random
import pygame

CELL = 20
COLS, ROWS = 24, 18
TURNS = {
    pygame.K_LEFT: (-1, 0),
    pygame.K_RIGHT: (1, 0),
    pygame.K_UP: (0, -1),
    pygame.K_DOWN: (0, 1),
}

pygame.init()
screen = pygame.display.set_mode((COLS * CELL, ROWS * CELL))
pygame.display.set_caption("Snake")
clock = pygame.time.Clock()


def draw_cell(cell, color):
    col, row = cell
    pygame.draw.rect(screen, color, (col * CELL + 1, row * CELL + 1, CELL - 2, CELL - 2))


def new_food(body):
    while True:
        cell = (random.randrange(COLS), random.randrange(ROWS))
        if cell not in body:
            return cell


body = [(5, 9), (4, 9), (3, 9)]
direction = (1, 0)
food = new_food(body)

running = True
while running:
    moving = direction
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        elif event.type == pygame.KEYDOWN and event.key in TURNS:
            turn = TURNS[event.key]
            if turn != (-moving[0], -moving[1]):
                direction = turn

    x = body[0][0] + direction[0]
    y = body[0][1] + direction[1]
    body.insert(0, (x, y))
    body.pop()

    screen.fill((30, 30, 46))
    draw_cell(food, (235, 80, 80))
    for cell in body[1:]:
        draw_cell(cell, (120, 220, 120))
    draw_cell(body[0], (180, 255, 160))
    pygame.display.flip()
    clock.tick(10)

pygame.quit()

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