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Cherry trees

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import turtle
 
from random import random
from random import randint
 
 
def draw_petal(turtle_obj, flower) :
    # Draw falling petals
    for i in range(int(flower)):
        # Positive and negative can make the brush go in both directions
        x = flower - 4 * flower * random()
 
        # Overall petal width (-10, 10)
        y = 10 - 20 * random()
 
        # Pick up pen, forward Y, turn left 90, go X, write
        turtle_obj.penup()
        turtle_obj.forward(y)
        turtle_obj.left(90)
        turtle_obj.forward(x)
        turtle_obj.pendown()
 
        # coral
        turtle_obj.pencolor("lightcoral")
        # circle
        turtle_obj.circle(1)
 
        # Back to square one
        # Pick up pen, back x, turn right 90, back Y, start pen
        turtle_obj.penup()
        turtle_obj.backward(x)
        turtle_obj.right(90)
        turtle_obj.backward(y)
        turtle_obj.pendown()
 
 
# Draw the branches
def draw_tree(turtle_obj, branch, tree_color) :
    Set a minimum branch length
    min_branch = 4
 
    if branch > min_branch:
        if branch < 8:
            Branch left and right with a probability of 0.5
            if randint(0.1) = =0:
                # left is white
                turtle_obj.pencolor("snow")
            else:
                # Coral on the right
                turtle_obj.pencolor("lightcoral")
            # branches
            turtle_obj.pensize(branch / 2)
        elif 8 <= branch <= 16:
            With a probability of 0.33, it is divided into left, middle and right branches
            if randint(0.2) = =0:
                # left is white
                turtle_obj.pencolor("snow")
            else:
                # Coral color in center and right
                turtle_obj.pencolor("lightcoral")
            # branch
            turtle_obj.pensize(branch / 4)
        else:
            # brown
            turtle_obj.pencolor(tree_color)
            # twigs
            turtle_obj.pensize(branch / 10)
 
        # Initial trunk length
        turtle_obj.forward(branch)
 
        # Random degree factor
        a = 1.5 * random()
        # Rotate clockwise at random Angle (0 ~ 30 degrees)
        turtle_obj.right(20 * a)
 
        # Random length factor
        b = 1.5 * random()
        # Draw to the right until you can't move
        draw_tree(turtle_obj, branch - 10 * b, tree_color)
 
        # Random left-turn Angle
        turtle_obj.left(40 * a)
        # Draw to the left until you can't move the position
        draw_tree(turtle_obj, branch - 10 * b, tree_color)
 
        # Turn right an Angle
        turtle_obj.right(20 * a)
        # start
        turtle_obj.penup()
 
        # Return to the starting point
        turtle_obj.backward(branch)
        turtle_obj.pendown()
 
 
def get_screen(width, height, color, speed) :
    Create a screen
    screen_obj = turtle.Screen()
    # canvas size: (width, height
    screen_obj.screensize(width, height, bg=color)
    screen_obj.setup(1.0.1.0)
    # speed up
    screen_obj.tracer(speed)
 
    return screen_obj
 
# Draw multiple trees
def trees(tree_num) :
    # color
    color = ['brown'.'tan'.'black']
 
    for j in range(tree_num):
        # Trunk color
        tree_color = color[randint(0.len(color) - 1)]
 
        # brush size
        pensize = randint(2.5)
        # forward pixels
        forward = ((-1) ** pensize) * pensize * randint(20.50)
        # back pixels
        if pensize <= 3:
            backward = ((-1) ** pensize) * (5 - pensize) * randint(10.15)
        else:
            backward = pensize * randint(45.50)
 
        # create brush
        turtle_obj = turtle.Turtle()
        # Brush thickness
        turtle_obj.pensize(pensize)
        # Pick up pen, forward forward, left 90, backward, draw pen
        turtle_obj.penup()
        turtle_obj.forward(forward)
        turtle_obj.left(90)
        turtle_obj.backward(backward)
        turtle_obj.pendown()
        # Brush color: brown
        turtle_obj.pencolor(tree_color)
 
        # Stem thickness
        branch = pensize * 15
        # the fallen petal number
        flowers = branch
        # JTH tree
        draw_tree(turtle_obj, branch, tree_color)
        # petals
        draw_petal(turtle_obj, flowers)
 
 
if __name__ == '__main__':
 
    Create a screen
    my_screen_width = 800
    my_screen_height = 600
    my_screen_color = 'wheat'
    my_screen_speed = 5
    my_screen_obj = get_screen(my_screen_width, my_screen_height,
                               my_screen_color, my_screen_speed)
 
    The cherry blossom trees #
    # tree
    my_tree_num = 5
    trees(my_tree_num)
 
    # Click close canvas
    my_screen_obj.exitonclick()
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