如何重置海龟并擦除海龟图形中的文本？

Question

I made this turtle game

import turtle
import random
import time
from turtle import Turtle

# Window

window = turtle.Screen()
window.title("Turtle Race")
window.bgcolor("forestgreen")
turtle.color("white")
turtle.speed(0)
turtle.penup()
turtle.setposition(-140, 200)
turtle.write("Turtle Race", font=("Arial", 40, "bold"))

# Dirt

turtle.setposition(-400, -180)
turtle.color("chocolate")
turtle.begin_fill()
turtle.pendown()
turtle.forward(800)
turtle.right(90)
turtle.forward(300)
turtle.right(90)
turtle.forward(800)
turtle.right(90)
turtle.forward(300)
turtle.end_fill()

# Finish line

stamp_size = 20
square_size = 15
finish_line = 200

turtle.color("black")
turtle.shape("square")
turtle.shapesize(square_size / stamp_size)
turtle.penup()

for i in range(10):
    turtle.setposition(finish_line, (150 - (i * square_size * 2)))
    turtle.stamp()

for j in range(10):
    turtle.setposition(finish_line + square_size, ((150 - square_size) - (j * square_size * 2)))
    turtle.stamp()

turtle.hideturtle()


def play():

    # Turtle 1

    turtle1 = Turtle()
    turtle1.speed(0)
    turtle1.color("black")
    turtle1.shape("turtle")
    turtle1.penup()
    turtle1.goto(-250, 100)
    turtle1.pendown()

    # Turtle 2

    turtle2 = Turtle()
    turtle2.speed(0)
    turtle2.color("cyan")
    turtle2.shape("turtle")
    turtle2.penup()
    turtle2.goto(-250, 50)
    turtle2.pendown()

    # Turtle 3

    turtle3 = Turtle()
    turtle3.speed(0)
    turtle3.color("magenta")
    turtle3.shape("turtle")
    turtle3.penup()
    turtle3.goto(-250, 0)
    turtle3.pendown()

    # Turtle 4

    turtle4 = Turtle()
    turtle4.speed(0)
    turtle4.color("yellow")
    turtle4.shape("turtle")
    turtle4.penup()
    turtle4.goto(-250, -50)
    turtle4.pendown()

    time.sleep(1)    # pausing the game for 1 sec before game starts

    # Asking user to play

    print("Please choose one colour out of \nBlack \nCyan \nMagenta \nYellow ")
    user_bet = input("Place your bet on your any one colour turtle: ").upper()

    while not(user_bet == "BLACK" or user_bet == "CYAN" or user_bet == "MAGENTA" or user_bet == "YELLOW"):
        print("Please choose one colour out of \nBlack \nCyan \nMagenta \nYellow ")
        user_bet = input("Place your bet on your any one colour turtle: ").upper()

    # Initial distance covered by turtles

    tut1_len = 0
    tut2_len = 0
    tut3_len = 0
    tut4_len = 0

    # Moving the turtles

    for _i in range(145):

        tut1 = random.randint(1, 5)
        tut2 = random.randint(1, 5)
        tut3 = random.randint(1, 5)
        tut4 = random.randint(1, 5)

        turtle1.forward(tut1)
        tut1_len += tut1

        turtle2.forward(tut2)
        tut2_len += tut2

        turtle3.forward(tut3)
        tut3_len += tut3

        turtle4.forward(tut4)
        tut4_len += tut4

    # Deciding the winner

    result_dic = {"black": tut1_len, "cyan": tut2_len, "magneta": tut3_len, "yellow": tut4_len}
    winner = max(result_dic, key=lambda x: result_dic[x]).upper()

    turtle.penup()
    turtle.color("blue")
    if user_bet == winner:
        turtle.goto(-140, 50)
        turtle.write("You won the bet", font=("Arial", 30, "bold"))
    else:
        turtle.goto(-140, 50)
        turtle.write("You lost the bet", font=("Arial", 30, "bold"))
    turtle.pendown()


play()

choice = input("Do you want to play again?\n Press y for yes and n for no: ").upper()

while choice == "y".upper() or choice == "yes".upper():
    play()
else:
    quit()

The game works and i wanted the game to ask user to play again and it does that but every time the game reruns the turtles run over previous turtle the the text which display ** You won the bet** or ** You lost the bet** is also written over previous another one.

I din't find any method to clear text written in screen nor to erase the turtles lines. Please help me.

And it would me really helpful if you guys give me suggestion on how to improve this code like how to make it more short and i am little confused about my own logic on line 106 about that or operator but this is secondary please help me on my primary problem first.

Answer 1

My recommendation in a situation like this, where text is being updated on the screen, is that you have a turtle dedicated just to writing that text. Put that turtle into position before the action starts and then just use clear() and write() on that turtle from then on. Don't use it for anything else.

it would me really helpful if you guys give me suggestion on how to improve this code

One key thing with a program like this is to not assume how many racers there will be, and write your code accordingly. You should be able to adjust the number up or down slightly (or just change your color choices) without having to do a major rewrite.

I've reworked your code to address both of the above issues:

from turtle import Screen, Turtle
from random import randint

STAMP_SIZE = 20
SQUARE_SIZE = 15
FINISH_LINE = 200
LANE_WIDTH = 50

BIG_FONT = ('Arial', 40, 'bold')
MEDIUM_FONT = ('Arial', 30, 'bold')

COLORS = ['black', 'cyan', 'magenta', 'yellow', 'white']

def play():
    pen.clear()

    lane = LANE_WIDTH

    for n, color in enumerate(COLORS, start=1):
        turtle = turtles[color]

        turtle.hideturtle()
        turtle.goto(-250, n // 2 * lane)
        turtle.showturtle()

        lane = -lane

    # Asking user to play

    user_bet = None

    while user_bet not in COLORS:
        print("Please choose one colour out of", *["\n" + color.title() for color in COLORS])
        user_bet = input("Place your bet on your any one colour turtle: ").lower()

    # Moving the turtles

    for _ in range(145):

        for turtle in turtles.values():
            distance = randint(1, 5)
            turtle.forward(distance)

    # Deciding the winner

    winner = max(turtles, key=lambda x: turtles[x].xcor())

    pen.clear()
    if user_bet == winner:
        pen.write("You won the bet!", align='center', font=MEDIUM_FONT)
    else:
        pen.write("You lost the bet.", align='center', font=MEDIUM_FONT)

# Screen

screen = Screen()
screen.title("Turtle Race")
screen.bgcolor('forestgreen')

turtle = Turtle()
turtle.hideturtle()
turtle.speed('fastest')
turtle.penup()

# Dirt

turtle.setposition(-400, -180)
turtle.color('chocolate')

turtle.begin_fill()
for _ in range(2):
    turtle.forward(800)
    turtle.right(90)
    turtle.forward(300)
    turtle.right(90)
turtle.end_fill()

# Finish line

turtle.color('black')
turtle.shape('square')
turtle.shapesize(SQUARE_SIZE / STAMP_SIZE)

for i in range(10):
    turtle.setposition(FINISH_LINE, 150 - i * SQUARE_SIZE*2)
    turtle.stamp()
    turtle.setposition(FINISH_LINE + SQUARE_SIZE, (150 - SQUARE_SIZE) - i * SQUARE_SIZE*2)
    turtle.stamp()

turtle.setposition(0, 200)
turtle.write("Turtle Race", align='center', font=BIG_FONT)

pen = Turtle()
pen.hideturtle()
pen.color('blue')
pen.penup()
pen.setposition(0, 50)

turtle_prototype = Turtle()
turtle_prototype.hideturtle()
turtle_prototype.shape('turtle')
turtle_prototype.speed('fastest')
turtle_prototype.penup()

turtles = {}

for color in COLORS:
    turtle = turtle_prototype.clone()
    turtle.color(color)
    turtles[color] = turtle

choice = 'yes'

while choice.lower() in ('y', 'yes'):

    play()

    choice = input("Do you want to play again?\nPress y for yes and n for no: ")