如何用python畫出五星紅旗 效果圖 代碼

效果圖

代碼

# coding=utf-8
import turtle
import math

def draw_polygon(aTurtle, size=50, n=3):
    ''' 繪製正多邊形
    args:
        aTurtle: turtle對象實例
        size: int類型，正多邊形的邊長
        n: int類型，是幾邊形
    '''
    for i in range(n):
        aTurtle.forward(size)
        aTurtle.left(360.0 / n)


def draw_n_angle(aTurtle, size=50, num=5, color=None):
    ''' 繪製正n角形，默認爲黃色
    args:
        aTurtle: turtle對象實例
        size: int類型，正多角形的邊長
        n: int類型，是幾角形
        color: str， 圖形顏色，默認不填色
    '''
    if color:
        aTurtle.begin_fill()
        aTurtle.fillcolor(color)
    for i in range(num):
        aTurtle.forward(size)
        aTurtle.left(360.0 / num)
        aTurtle.forward(size)
        aTurtle.right(2 * 360.0 / num)
    if color:
        aTurtle.end_fill()


def draw_5_angle(aTurtle=None, start_pos=(0, 0), end_pos=(0, 10), radius=100, color=None):
    ''' 根據起始位置、結束位置和外接圓半徑畫五角星
    args:
        aTurtle: turtle對象實例
        start_pos: int的二元tuple，要畫的五角星的外接圓圓心
        end_pos: int的二元tuple，圓心指向的位置座標點
        radius: 五角星外接圓半徑
        color: str， 圖形顏色，默認不填色
    '''
    aTurtle = aTurtle or turtle.Turtle()
    # size = radius * math.sin(math.pi/5)/math.sin(math.pi*2/5)計算公式錯誤，但不影響顯示
    size = radius * math.sin(math.pi / 5) / math.sin(math.pi * 3 / 10)  # 修正
    angle = math.degrees(math.atan2(end_pos[1] - start_pos[1], end_pos[0] - start_pos[0]))
    print(angle)
    aTurtle.penup()
    aTurtle.goto(start_pos)
    aTurtle.setheading(0)
    aTurtle.left(angle)
    aTurtle.fd(radius)
    aTurtle.pendown()
    aTurtle.right(math.degrees(math.pi * 9 / 10))
    draw_n_angle(aTurtle, size, 5, color)


def draw_5_star_flag(times=20.0):
    ''' 繪製五星紅旗
    args:
        times: 五星紅旗的規格爲30*20， times爲倍數，默認大小爲10倍， 即300*200
    '''
    width, height = 30 * times, 20 * times
    # 初始化屏幕和海龜
    window = turtle.Screen()
    aTurtle = turtle.Turtle()
    aTurtle.hideturtle()
    aTurtle.speed(10)
    # 畫紅旗
    aTurtle.penup()
    aTurtle.goto(-width / 2, height / 2)
    aTurtle.pendown()
    aTurtle.begin_fill()
    aTurtle.fillcolor('red')
    aTurtle.fd(width)
    aTurtle.right(90)
    aTurtle.fd(height)
    aTurtle.right(90)
    aTurtle.fd(width)
    aTurtle.right(90)
    aTurtle.fd(height)
    aTurtle.right(90)
    aTurtle.end_fill()
    # 畫大星星
    draw_5_angle(aTurtle, start_pos=(-10 * times, 5 * times), end_pos=(-10 * times, 8 * times), radius=3 * times,color='yellow')
    # 畫四個小星星
    stars_start_pos = [(-5, 8), (-3, 6), (-3, 3), (-5, 1)]
    for pos in stars_start_pos:
        draw_5_angle(aTurtle, start_pos=(pos[0] * times, pos[1] * times), end_pos=(-10 * times, 5 * times),radius=1 * times, color='yellow')
        # 點擊關閉窗口
    window.exitonclick()


if __name__ == '__main__':
    draw_5_star_flag()