如何在Turtle Graphics Python 3中设置绘图点

Question

I'm using Turtle Graphics Module in Python 3 and I have drawn a Circle using circle method of Turtle with that i'm using Custom Shape which is a pencil, now problem is that i'ts drawing from the center of the pencil. I want it to draw from the tip of the Pencil, so how can i setup turtle to start drawing from the tip of the pencil rather than from the center point. Here is my Code:

from turtle import Screen, Turtle
screen = Screen()
screen.setup(500, 500)
screen.screensize(500, 500)
screen.register_shape('dpen.gif')
turtle = Turtle('dpen.gif')


def draw_circle():
    turtle.home()
    turtle.clear()
    turtle.circle(90)


screen.listen()
screen.onkeypress(draw_circle, 'space')
screen.mainloop()

Thank You

Answer 1

When setting a custom pen, turtle will always draw from the centre of your image. There might be a way to change this, but a far simpler solution is to change your image so that the pencil is in the top right corner, so that the tip points to the middle of the image. Took me 10 seconds in powerpoint

Very crude example image (demonstrates point):