Rounded edge rectangles with Python turtle

问题

Is there another way to add a rounded edge to square/rectangle shapes apart from drawing a circle and drawing a square over it? I am trying to make the YouTube logo using only Python turtle. I didn't use absolute position functions like home(), as I need replicate this at different locations later on.

from turtle import *



def placement():
    penup()
    setheading(0)
    forward(5)
    setheading(90)
    forward(20)
    setheading(0)
    pendown()

def youtube():
    placement() #Custom Starting poisition
    hideturtle()
    pencolor("#d43b33") # Pen Color
    fillcolor("#d43b33") #Youtube Red Colour RGB Code
    begin_fill()
    forward(90)
    setheading(90) #Face Up
    forward(30)
    setheading(180) #Face Left
    forward(90)
    setheading(270) #Face Down
    forward(30)
    end_fill()
    setheading(0) #Second Half Youtube Logo
    forward(90)
    setheading(90)
    forward(30)
    pencolor("#fa453b") # Pen Color
    fillcolor("#fa453b") #Youtube Ligther Red Colour RGB Code
    begin_fill()
    forward(30)
    setheading(180) # Face Left
    forward(90)
    setheading(270) #Face Down
    forward(30)    
    setheading(0) #turn right
    forward(90)
    end_fill()
    penup()
    fillcolor("#ffffff") #Youtube White Play button RGB Code
    setheading(180)
    forward(55)
    setheading(90)
    begin_fill()
    forward(20)
    setheading(315)
    forward(30)
    setheading(225)
    forward(30)
    setheading(90)
    forward(20)
    end_fill()

Draw

回答1:

First, I don't believe that the YouTube logo is a rounded rectangle, but rather a hyperellipse. But let's assume a rounded rectangle to keep things simple. Second, I don't believe your colors, nor your arrow, conform to the YouTube Brand so I'll adjust those things slightly:

from turtle import Turtle, Screen

def rounded_rectangle(turtle, short, long, radius):
    diameter = radius * 2

    heading = turtle.heading()
    turtle.setheading(270)

    isdown = turtle.isdown()
    if isdown:
        turtle.penup()

    turtle.goto(turtle.xcor() - long/2, turtle.ycor() - short/2 + radius)

    turtle.pendown()

    for _ in range(2):
        turtle.circle(radius, 90)
        turtle.forward(long - diameter)
        turtle.circle(radius, 90)
        turtle.forward(short - diameter)

    turtle.penup()  # restore turtle state, position and heading
    turtle.goto(turtle.xcor() + long/2, turtle.ycor() + short/2 - radius)
    if isdown:
        turtle.pendown()
    turtle.setheading(heading)

def youtube(turtle):
    turtle.color("#ff0000")  # YouTube red pen color RGB code

    turtle.begin_fill()
    rounded_rectangle(turtle, 60, 90, 10)
    turtle.end_fill()

    turtle.penup()

    turtle.color("#ffffff")  # YouTube white play button RGB code
    turtle.setheading(0)
    turtle.backward(8)
    turtle.setheading(90)

    turtle.pendown()

    turtle.begin_fill()
    turtle.forward(12)
    for _ in range(2):
        turtle.right(120)
        turtle.forward(24)
    turtle.right(120)
    turtle.forward(12)
    turtle.end_fill()

def placement(turtle):
    turtle.penup()
    turtle.forward(5)
    turtle.left(90)
    turtle.forward(20)
    turtle.right(90)
    turtle.pendown()

screen = Screen()

yertle = Turtle(visible=False)

placement(yertle)  # Custom starting position

youtube(yertle)

screen.mainloop()

来源：https://stackoverflow.com/questions/52005422/rounded-edge-rectangles-with-python-turtle