Змейка в игре передвигается по частям, а не целиком

Question

Моя игра - игра со змеями, где вы должны получить фрукты. Это код:

#Importing random and turtle module 
import random
import turtle as t #Shortening the turtle module to t

#Adding a orange background
t.bgcolor("orange")

#Creating a turtle to become the snake
snake = t.Turtle() # Creates a new turtle for the snake
snake.shape("square") # Making the snake square shaped
snake.color("green") # Making the snake green
snake.speed(0) # Making the snake not move before the game starts
snake.penup() # Disables the turtles pen allowing the turtle to move around the screen without drawing a line along the way
snake.hideturtle() #This command hides the turtle

#Creating a turtle to draw the leaves
fruit = t.Turtle() # Creates a new turtle for the fruit
fruit.shape("circle") # Making the fruit circular
fruit.color("red") # Making the fruit red
fruit.penup() # Disables the turtles pen allowing the turtle to move around the screen without drawing a line along the way
fruit.hideturtle() #This command hides the turtle
fruit.speed(0) # Making the fruit not move

#Adding more turtles to display the text for the game and the score
gamestarted = False #To know if the game has started
writeturtle = t.Turtle()# Creates a new turtle for the text
writeturtle.write("Press SPACE to play!", align="center", font=("Calibri", 16, "bold")) #This line draws text on the screen
writeturtle.hideturtle() # Hides the turtle but not the text
#Adding a score turtle
scoreturtledude = t.Turtle()# Creates a new turtle for the score
scoreturtledude.hideturtle()#This command hides the turtle
scoreturtledude.speed(0)#Make sure the turtle stays where it is so it can update the score

def outsidewindow(): #Defining the outside window function
    leftwall = -t.window_width() / 2 #Calculates the left wall
    rightwall = t.window_width() / 2 #Calculates the right wall
    topwall = t.window_height() / 2 #Calculates the top wall
    bottomwall = -t.window_height() / 2 #Calculates the bottom wall
    (x, y) = snake.pos() #Then it asks the snake for its current position
    outside = x< leftwall or x> rightwall or y< bottomwall or y> topwall #Comparing the snakes coordinates with the wall position
    return outside #If any of the four conditions above is true then outside is true
def gameover(): #Defining gameover
    snake.color("orange")#CHANGES THE COLOR OF THE SNAKE TO ORANGE(the same color as the background) so it can't be seen
    fruit.color("orange")#CHANGES THE COLOR OF THE SNAKE TO ORANGE(the same color as the background) so it can't be seen
    t.penup() # this disables the turtles pen
    t.hideturtle() #This hides the turtle
    t.write("YOUR SNAKE CRAWLED INTO THE GARDEN. GAME OVER!", align="center", font=("Calibri", 20, "normal"))#This line writes a text for when the game is over
def showscore(currentscore):
    scoreturtledude.clear()# This clears the score
    scoreturtledude.penup()# Disables turtle pen
    x = (t.window_width() / 2) -75 # 75 pixels from the right
    y = (t.window_height() / 2) -75 # And 75 pixels from the top
    scoreturtledude.setpos(x, y)#Sets the turtles position
    scoreturtledude.write(str(currentscore) , align="right", font=("Calibri", 40, "bold"))# WRITES THE SCOre in calibri font
def placefruit():
    fruit.hideturtle()
    fruit.setposition(random.randint(-200, 200), random.randint(-200, 200))
    fruit.showturtle()
def startgame():
    global gamestarted
    if gamestarted: #If the game has already started, the return command makes the function quit so it doesn't run a second time
        return
    gamestarted = True

    score = 0 #Sets the score to 0
    writeturtle.clear() # Clears the text from the screen

    snakespeed = 2
    snakelength = 3
    snake.shapesize(1, snakelength, 1)#This makes the snake turtle stretch from a square shape into a snake shape
    snake.showturtle() #This shows the snake
    showscore(score) #This uses the showscore function we defined earlier
    placefruit()
    while True: #This puts it in a forever loop
        snake.forward(snakespeed)
        if snake.distance(fruit) < 20:# Makes the snake eat the leaf when it is less than 20 pixels away
            placefruit() #This line places another fruit on the screen
            snakelength = snakelength + 1 #This line line and the next line together will make the snake grow longer
            snake.shapesize(1, snakelength, 1)
            snakespeed = snakespeed + 1 #This increases the speed of the snake
            score = score + 100 #This increases the score
            showscore(score) #This shows the score
        if outsidewindow():
               gameover()
               break
def up():
    if snake.heading() == 0 or snake.heading() == 180: #checks if the snake is heading left or right
        snake.setheading(90)#Heads the snake straight up
def down():
    if snake.heading() == 0 or snake.heading() == 180:#checks if the snake is heading left or right
        snake.setheading(270)#Heads the snake straight down
def left():
    if snake.heading() == 90 or snake.heading() == 270:#checks if the snake is heading  up or down
        snake.setheading(180)#Heads the snake straight right
def right():
    if snake.heading() == 90 or snake.heading() == 270:#checks if the snake is heading up or down
        snake.setheading(0)#Heads the snake straight left


t.onkey(startgame, "space") # The onkey() function binds yhe space bar to the startgame () so the game will not start until the player presses space
t.onkey(up, "Up") #The onkey() function binds the up key to the startgame 
t.onkey(down, "Down")#The onkey() function binds the down key to the startgame 
t.onkey(right, "Right")#The onkey() function binds the right key to the startgame 
t.onkey(left, "Left")#The onkey() function binds the left key to the startgame 
t.listen() # The listen function allows the program to recieve signals from the key board
t.mainloop()

Этот код делает игру, в которой змея поворачивается совсем, но я хочу, чтобы змея поворачивалась по частям. Не могли бы вы помочь мне?

Answer 1

Ниже я объединил вашу игру с этим коротким примером , как перемещать сегментированную змею по экрану , который я написал ранее - я удивлен, что ваш поиск SO не включил это .

Я также сделал некоторые другие изменения, чтобы приспособить это движение. Ваша змея превращается из черепахи в список черепах, а последней черепахой в списке является голова змеи. Обработчики стрелок на клавиатуре больше не изменяют направление змеи напрямую, они просто устанавливают новую переменную направления для следующего движения черепахи - это предотвращает конфликты при регулировке черепахи.

Вашему while True: нет места в управляемом событиями мире, таком как черепаха, поэтому его заменили на событие ontimer(), иначе вы потенциально можете заблокировать события:

from random import randint
from turtle import Turtle, Screen  # force object-oriented turtle

SCORE_FONT = ("Calibri", 40, "bold")
MESSAGE_FONT = ("Calibri", 24, "bold")

SEGMENT_SIZE = 20

def outsidewindow():
    (x, y) = snake[-1].pos()  # Ask the snake head for its current position
    return not (leftwall < x < rightwall and bottomwall < y < topwall)

def gameover():
    for segment in snake:
        segment.hideturtle()
    fruit.hideturtle()
    writeturtle.write("Your snake crawled into the garden! Game over!", align="center", font=MESSAGE_FONT)

def showscore(currentscore):
    scoreturtledude.undo() # Clear the previous score
    scoreturtledude.write(currentscore, align="right", font=SCORE_FONT)

def placefruit():
    fruit.hideturtle()
    fruit.setposition(randint(-200, 200), randint(-200, 200))
    fruit.showturtle()

def startgame():
    screen.onkey(None, "space")  # So this doesn't run a second time

    writeturtle.clear() # Clear the text from the screen

    showscore(score)

    for segment in snake: # Show the snake
        segment.showturtle()

    placefruit()

    rungame()

def rungame():
    global score, snakelength

    segment = snake[-1].clone() if len(snake) < snakelength else snake.pop(0)

    screen.tracer(False)  # segment.hideturtle()
    segment.setposition(snake[-1].position())
    segment.setheading(snake[-1].heading())
    segment.setheading(direction)
    segment.forward(SEGMENT_SIZE)

    if outsidewindow():
        gameover()
        return

    screen.tracer(True)  # segment.showturtle()
    snake.append(segment)

    if snake[-1].distance(fruit) < SEGMENT_SIZE:  # Make the snake eat the fruit when it is nearby
        placefruit()  # Place another fruit on the screen
        snakelength += 1
        score += 100
        showscore(score)

    screen.ontimer(rungame, max(50, 150 - 10 * len(snake)))  # Speed up slightly as snake grows

def up():
    global direction

    current = snake[-1].heading()

    if current == 0 or current == 180:  # Check if the snake is heading left or right
        direction = 90  # Head the snake up

def down():
    global direction

    current = snake[-1].heading()

    if current == 0 or current == 180:  # Check if the snake is heading left or right
        direction = 270  # Head the snake down

def left():
    global direction

    current = snake[-1].heading()

    if current == 90 or current == 270:  # Check if the snake is heading up or down
        direction = 180  # Head the snake left

def right():
    global direction

    current = snake[-1].heading()

    if current == 90 or current == 270:  # Check if the snake is heading up or down
        direction = 0  # Head the snake right

screen = Screen()
screen.bgcolor("orange")

leftwall = -screen.window_width() / 2  # Calculate the left wall
rightwall = screen.window_width() / 2  # Calculate the right wall
topwall = screen.window_height() / 2  # Calculate the top wall
bottomwall = -screen.window_height() / 2  # Calculate the bottom wall

# Creating a turtle to become the snake
head = Turtle("square", visible=False) # Create a new turtle for the snake
head.color("green") # Make the snake green
head.penup() # Disable the turtle's pen, allowing the turtle to move around the screen without leaving a trail

snake = [head]
snakelength = 3
score = 0
direction = 0

# Creating a turtle to draw the leaves
fruit = Turtle("circle", visible=False) # Create a turtle for the fruit
fruit.penup() # Raise the turtle's pen, allowing turtle to move around screen without leaving a trail
fruit.color("red")

# Add more turtles to display the text for the game and the score
writeturtle = Turtle(visible=False)  # Create a new turtle for the text
writeturtle.write("Press SPACE to play!", align="center", font=MESSAGE_FONT)

# Add a score turtle
scoreturtledude = Turtle(visible=False)  # Create a new turtle for the score
scoreturtledude.penup()  # Disable turtle pen
x = screen.window_width() / 2 - 75  # 75 pixels from the right
y = screen.window_height() / 2 - 75  # And 75 pixels from the top
scoreturtledude.setpos(x, y) # Set the turtle's position
scoreturtledude.write('', align="right", font=SCORE_FONT)

screen.onkey(startgame, "space")  # Bind space bar to startgame() so game will start when player presses space
screen.onkey(up, "Up")  # Bind the up key to up()
screen.onkey(down, "Down")  # Bind the down key to down()
screen.onkey(right, "Right")  # Bind the right key to right()
screen.onkey(left, "Left")  # Bind the left key to left()
screen.listen()  # Allow the window to receive signals from the keyboard

screen.mainloop()

У вас есть ряд проблем в вашем коде, например, малышам нравится, что за черепаха gameover() имеет в виду, когда она делает t.hideturtle()? Но два основных из них:

• Перечитайте, что делает speed(0) - вы неправильно поняли.

• Вам нужно научиться писать лучшие комментарии. Это глупо:

  fruit.color ("red") # Делаем фрукты красными

  Это очень хорошо:

  t.listen () # Функция прослушивания позволяет программе получать сигналы с клавиатуры