drawing a point on the screen every 17ms in Python?

Question

I managed to string together a script that receives commands from an iOS app setting velocity and a direction.

The thing is I do not have the actual device, so my ap

Answer 1

You could use your terminal as a "window" and draw a "circle" in it. As a very simple (and unreliable) "timer", time.sleep() function could be used:

#!/usr/bin/env python
"""Print red circle walking randomly in the terminal."""
import random
import time
from blessings import Terminal # $ pip install blessings colorama
import colorama; colorama.init() # for Windows support (not tested)

directions = [(-1, -1), (-1, 0), (-1, 1),
              ( 0, -1),          ( 0, 1),
              ( 1, -1), ( 1, 0), ( 1, 1)]
t = Terminal()
with t.fullscreen(), t.hidden_cursor():
    cur_y, cur_x = t.height // 2, t.width // 2 # center of the screen
    nsteps = min(cur_y, cur_x)**2 # average distance for random walker: sqrt(N)
    for _ in range(nsteps):
        y, x = random.choice(directions)
        cur_y += y; cur_x += x # update current coordinates
        print(t.move(cur_y, cur_x) +
              t.bold_red(u'\N{BLACK CIRCLE}')) # draw circle
        time.sleep(6 * 0.017) # it may sleep both less and more time
        print(t.clear) # clear screen

To try it, save the code into random-walker.py and run it:

$ python random-walker.py

I don't know whether it works on Windows.