为什么乌龟没有填充封闭形状的一部分答案

【问题标题】：Why is turtle not filling in a section of a closed shape为什么乌龟没有填充封闭形状的一部分
【发布时间】：2021-10-05 02:19:28
【问题描述】：

我正在尝试用海龟填充一个形状，但是当我这样做时，一小部分最终没有被填充。我该如何解决这个问题？我试着让它上升的线越过空白区域开始的点，但这没有用。正如您可能从我的代码中看到的那样，我对 python 还是很陌生。这是我的代码...

import turtle

turtl = turtle.Turtle()
turtle.screensize(852, 508, 'white')
turtl.penup()
turtl.fillcolor("royal blue")      #Every closed shape after this untill endfill() will be filled with royal blue
turtl.begin_fill()

for i in range(1):
    turtl.hideturtle()
    turtl.penup()
    turtl.setx(-213)
    turtl.sety(-75)      #Moves the turtle to the correct place to start the "plus"
    turtl.right(180)
    turtl.pendown()
    turtl.forward(427)      #Makes the first line going left
    turtl.right(90)
    turtl.forward(150)      #Width of plus
    turtl.right(90)
    turtl.forward(427)
    turtl.left(90)
    turtl.forward(253)      #Going to top of plus
    turtl.right(90)
    turtl.forward(150)      #Width of top of plus
    turtl.right(90)
    turtl.forward(253)      #Going back down from right side of top of plus
    turtl.left(90)
    turtl.forward(697)      #Going to the right side of the screen
    turtl.right(90)
    turtl.forward(150)      #Width of plus / Start of bottom half of plus
    turtl.right(90)
    turtl.forward(697)      #Going back left to to the bottom bit of the plus
    turtl.left(90)
    turtl.forward(253)     #Going to the bottom part of plus
    turtl.right(90)
    turtl.forward(150)
    turtl.right(90)
    turtl.forward(253)      #Traveling back up to center bar

turtl.end_fill()

print(turtl)
turtle.mainloop()

【问题讨论】：

标签： python turtle-graphics python-turtle

【解决方案1】：

您应该在 begin_fill 之前将海龟移动到起始位置，因为它似乎将此移动 setx(), sety() 视为线 - 即使您使用 penup() - 并且这条线会在图中创建白色三角形。

import turtle

turtl = turtle.Turtle()

turtle.screensize(852, 508, 'white')

turtl.penup()
turtl.setx(-213)
turtl.sety(-75)      #Moves the turtle to the correct place to start the "plus"
turtl.right(180)
turtl.pendown()

turtl.fillcolor("royal blue")      #Every closed shape after this untill endfill() will be filled with royal blue
turtl.begin_fill()

for i in range(1):
    turtl.hideturtle()
    turtl.forward(427)      #Makes the first line going left
    turtl.right(90)
    turtl.forward(150)      #Width of plus
    turtl.right(90)
    turtl.forward(427)
    turtl.left(90)
    turtl.forward(253)      #Going to top of plus
    turtl.right(90)
    turtl.forward(150)      #Width of top of plus
    turtl.right(90)
    turtl.forward(253)      #Going back down from right side of top of plus
    turtl.left(90)
    turtl.forward(697)      #Going to the right side of the screen
    turtl.right(90)
    turtl.forward(150)      #Width of plus / Start of bottom half of plus
    turtl.right(90)
    turtl.forward(697)      #Going back left to to the bottom bit of the plus
    turtl.left(90)
    turtl.forward(253)     #Going to the bottom part of plus
    turtl.right(90)
    turtl.forward(150)
    turtl.right(90)
    turtl.forward(253)      #Traveling back up to center bar

turtl.end_fill()

turtle.mainloop()

【讨论】：

【解决方案2】：

首先，我认为您拥有的for 循环是不必要的，因为它有一个range(1)，这意味着它只会运行一次，这与没有for 相同环形。关于您的问题，只需将setx(x) 和sety(y) 替换为单个goto(x,y)，如下所示：

原文：

for i in range(1):
    turtl.hideturtle()
    turtl.penup()
    turtl.setx(-213)
    turtl.sety(-75)
    turtl.right(180)

修订：

for i in range(1):
    turtl.hideturtle()
    turtl.penup()
    turtl.goto(-213,-75)
    turtl.right(180)

【讨论】：

【解决方案3】：

已经为您提供了两个可行的解决方案（每个 +1），所以我想解决您代码中的另一个问题：不要使用 screensize()，它不能满足您的要求。请改用setup()。下面的示例用法以及使用 stamping 而不是 drawing 绘制图形的完全不同的方式：

from turtle import Screen, Turtle

WIDTH, HEIGHT = 852, 508

THICKNESS = 150

CURSOR_SIZE = 20

screen = Screen()
screen.setup(WIDTH, HEIGHT)

turtle = Turtle()
turtle.hideturtle()
turtle.shape('square')
turtle.color("royal blue")
turtle.penup()

turtle.setx(-WIDTH/6)

turtle.shapesize(HEIGHT/CURSOR_SIZE, THICKNESS/CURSOR_SIZE)

turtle.stamp()

turtle.shapesize(THICKNESS/CURSOR_SIZE, (7*WIDTH/6 + THICKNESS)/CURSOR_SIZE)

turtle.stamp()

screen.mainloop()

【讨论】：