How to detect the edge of a window in python

Question

I was trying to make a worm AI thingy that moves around using python turtle and , but I don’t know how to detect the edge of the turtle window for it do evade it. pls help

Answer 1

You can get window's width

WIDTH = screen.window_width()

and then turtle may have position x in range -WIDTH/2 ... WIDTH/2 and you can do

x, y = turtle.pos()

if x > WIDTH/2:
    turtle.setx(-WIDTH/2)

if x < -WIDTH/2:
    turtle.setx(WIDTH/2)

Similar you can do for position y and window_height().

---

Minimal working example:

import turtle

screen = turtle.Screen()
WIDTH = screen.window_width()

t = turtle.Turtle()
t.penup()
t.speed(0)

while True:
    t.forward(5)
    x, y = t.pos()
    if x > WIDTH/2:
        t.setx(-WIDTH/2)
    screen.update()

---

EDIT:

More complex version with 10 turtles which move like in game Asteroid

import turtle

def check_border(t):
    x, y = t.pos()

    if x > WIDTH/2:
        t.setx(-WIDTH/2)
        #x -= WIDTH
        #t.setx(x)
    if x < -WIDTH/2:
        t.setx(WIDTH/2)
        #x += WIDTH
        #t.setx(x)
        
    if y > HEIGHT/2:
        t.sety(-HEIGHT/2)
        #y -= HEIGHT
        #t.sety(y)
    if y < -HEIGHT/2:
        t.sety(HEIGHT/2)
        #y += HEIGHT
        #t.sety(y)
    
# --- main --

screen = turtle.Screen()
WIDTH  = screen.window_width()
HEIGHT = screen.window_height()

all_turtles = []
for angle in range(0, 360, 36):
    t = turtle.Turtle()
    t.penup()
    t.speed(0)
    t.left(angle)
    all_turtles.append(t)

while True:

    for t in all_turtles:    
        t.forward(15)
        check_border(t)
        
    screen.update()