Python Turtle 透明填充？

Question

我正在尝试使用 Turtle 库重新创建这张图片：

但我在尝试使内部圈子“透明”时遇到了困难。 我搜索了文档，但找不到更改圆圈填充颜色的不透明度的方法。

我尝试的是：

colors = ["black", "magenta", "pink", "blue", "green", "yellow", "orange", "red", "white"]

for i in range(8):
    my_turtle.fillcolor(colors[i])
    my_turtle.begin_fill()
    my_turtle.circle(150)
    my_turtle.end_fill()
    my_turtle.fillcolor("white")
    my_turtle.begin_fill()
    my_turtle.circle(130)
    my_turtle.end_fill()
    my_turtle.fillcolor(colors[i])
    my_turtle.begin_fill()
    my_turtle.circle(100)
    my_turtle.end_fill()
    my_turtle.fillcolor("white")
    my_turtle.begin_fill()
    my_turtle.circle(80)
    my_turtle.end_fill()
    my_turtle.rt(45)

但我得到的是：

有什么想法吗？

Answer 1

您可以反转每个较小的圆圈颜色：

colors = ["black", "magenta", "pink", "blue", "green", "yellow", "orange", "red", "white"]

for i in range(8):
    my_turtle.fillcolor(colors[i])
    my_turtle.begin_fill()
    my_turtle.circle(150)
    my_turtle.circle(130, -360)
    my_turtle.end_fill()
    my_turtle.fillcolor(colors[i])
    my_turtle.begin_fill()
    my_turtle.circle(100)
    my_turtle.circle(80, -360)
    my_turtle.end_fill()
    my_turtle.rt(45)

输出：

Answer 2

您可能不需要像@AnnZen 建议的那样添加负号，而是注释字符。您的代码删除了以下几行，对我来说可以正常工作：

for i in range(8):
    my_turtle.fillcolor(colors[i])
    my_turtle.begin_fill()
    my_turtle.circle(150)
    # my_turtle.end_fill()
    # my_turtle.fillcolor("white")
    # my_turtle.begin_fill()
    my_turtle.circle(130)
    my_turtle.end_fill()
    # my_turtle.fillcolor(colors[i])
    my_turtle.begin_fill()
    my_turtle.circle(100)
    # my_turtle.end_fill()
    # my_turtle.fillcolor("white")
    # my_turtle.begin_fill()
    my_turtle.circle(80)
    my_turtle.end_fill()
    my_turtle.rt(45)

一个完整的解决方案：

from turtle import Screen, Turtle

COLORS = ['black', 'magenta', 'pink', 'blue', 'green', 'yellow', 'orange', 'red']

screen = Screen()
screen.tracer(False)

turtle = Turtle()
turtle.width(6)

for color in COLORS:
    turtle.fillcolor(color)

    turtle.begin_fill()
    turtle.circle(145)
    turtle.circle(130)
    turtle.end_fill()

    turtle.begin_fill()
    turtle.circle(115)
    turtle.circle(100)
    turtle.end_fill()

    turtle.right(45)

turtle.hideturtle()

screen.tracer(True)
screen.exitonclick()

Ann Zen 解决方案中的负号使每个环成为一个多边形， 在某一点接触自己，但从不与自己重叠。您的解决方案 产生自重叠的多边形，其基于不同的结果 关于正在使用的多边形填充规则（“奇偶”与“非零绕组” 号”）。

是的，我们以前见过这种情况，通常带有填充的五角星。让我们进一步推动@AnnZen 的负范围解决方案，在填充之前绘制一个完整的双弧：

from turtle import Screen, Turtle

COLORS = ['black', 'magenta', 'pink', 'blue', 'green', 'yellow', 'orange', 'red']

screen = Screen()

turtle = Turtle()
turtle.width(6)

for color in COLORS:
    turtle.fillcolor(color)

    turtle.begin_fill()
    turtle.circle(145)
    turtle.circle(130, -360)
    turtle.circle(115)
    turtle.circle(100, -360)
    turtle.end_fill()

    turtle.right(45)

turtle.hideturtle()

screen.exitonclick()

这在绕组数方面表现良好吗？