from GameChild import GameChild

class Animation(GameChild):

    def __init__(self, parent, method=None, interval=None, unfiltered=False):
        GameChild.__init__(self, parent)
        self.unfiltered = unfiltered
        self.default_method = method or self.build_frame
        self.accounts = {}
        self.register(self.default_method, interval=interval)
        self.current_elapsed = 0
        self.last_update = 0

    def build_frame(self):
        pass

    def register(self, *args, **kwargs):
        interval = None
        if kwargs.has_key("interval"):
            interval = kwargs["interval"]
        for method in args:
            if method not in self.accounts:
                self.accounts[method] = Account(interval, self)
            else:
                self.accounts[method].set_interval(interval)

    def play(self, method=None, interval=None, delay=0, play_once=False,
             **kwargs):
        account = self.accounts[self.get_default(method)]
        account.set_delay(delay)
        account.set_args(kwargs)
        account.set_play_once(play_once)
        if interval:
            account.set_interval(interval)
        account.play()

    def get_default(self, method=None):
        if not method:
            method = self.default_method
        return method

    def halt(self, method=None):
        if not method:
            for account in self.accounts.values():
                account.halt()
        else:
            if self.accounts.has_key(method):
                self.accounts[method].halt()

    def is_playing(self, method=None, check_all=False, include_delay=False):
        if check_all:
            return any(self.is_account_playing(account, include_delay) for \
                       method, account in self.accounts.iteritems())
        return self.is_account_playing(self.accounts[self.get_default(method)],
                                       include_delay)

    def is_account_playing(self, account, include_delay):
        return account.playing and (not include_delay or not account.delay)

    def reset_timer(self, method):
        if not method:
            for account in self.accounts.values():
                account.reset_timer()
        else:
            self.accounts[method].reset_timer()

    def update(self):
        for method, account in self.accounts.iteritems():
            if account.update():
                method(**account.args)


class Account:

    def __init__(self, interval, animation):
        self.animation = animation
        self.time_filter = animation.get_game().time_filter
        self.set_interval(interval)
        self.set_delay(0)
        self.set_play_once(False)
        self.interval_index = 0
        self.last_frame = 0
        self.halt()

    def set_interval(self, interval):
        if isinstance(interval, int) or isinstance(interval, str):
            interval = [interval]
        self.interval = interval

    def set_delay(self, delay):
        self.delay = delay

    def set_play_once(self, play_once):
        self.play_once = play_once

    def set_args(self, args):
        self.args = args

    def play(self):
        self.playing = True

    def halt(self):
        self.last_update = None
        self.playing = False

    def update(self):
        if self.playing:
            if self.animation.unfiltered:
                ticks = self.time_filter.get_unfiltered_ticks()
            else:
                ticks = self.time_filter.get_ticks()
            self.update_delay(ticks)
            if not self.delay:
                interval = self.interval
                if interval:
                    if ticks - self.last_frame < self.get_current_interval():
                        return False
                    self.last_frame = ticks
                    self.increment_interval_index()
                if self.play_once:
                    self.halt()
                return True

    def get_current_interval(self):
        return self.interval[self.interval_index]

    def increment_interval_index(self, increment=1):
        index = self.interval_index + increment
        while index >= len(self.interval):
            index -= len(self.interval)
        self.interval_index = index

    def reset_interval(self):
        self.interval_index = 0

    def reset_timer(self):
        if self.animation.unfiltered:
            ticks = self.time_filter.get_unfiltered_ticks()
        else:
            ticks = self.time_filter.get_ticks()
        self.last_frame = ticks

    def update_delay(self, ticks):
        delay = self.delay
        if delay > 0:
            last_update = self.last_update or ticks
            delay -= ticks - last_update
            if delay < 0:
                delay = 0
        self.last_update = ticks
        self.delay = delay
from pygame.event import get, pump, Event, post
from pygame.locals import *

from GameChild import GameChild
from Input import Input

class Delegate(GameChild):

    def __init__(self, game):
        GameChild.__init__(self, game)
        self.subscribers = dict()
        self.load_configuration()
        self.disable()

    def load_configuration(self):
        config = self.get_configuration("event")
        self.cancel_flag_key = config["cancel-flag-key"]
        self.command_key = config["command-key"]
        self.command_event_id = config["command-id-offset"] + \
                                globals()[config["user-event-id"]]

    def disable(self):
        self.enabled = False

    def enable(self):
        self.enabled = True
        self.interpolator = self.get_game().interpolator

    def dispatch(self):
        if self.enabled:
            subscribers = self.subscribers
            for evt in get():
                kind = evt.type
                if kind in subscribers:
                    for subscriber in subscribers[kind]:
                        if not self.interpolator.is_gui_active() or \
                               hasattr(subscriber, "im_class") and \
                               (subscriber.im_class == Input or \
                                subscriber.im_class == \
                                self.interpolator.gui.__class__):
                            self.print_debug("Passing %s to %s" % (evt,
                                                                   subscriber))
                            subscriber(evt)
        else:
            pump()

    def add_subscriber(self, callback, kind=None):
        self.print_debug("Subscribing %s to %s" % (callback, kind))
        if kind is None:
            kind = self.command_event_id
        subscribers = self.subscribers
        if kind not in subscribers:
            subscribers[kind] = list()
        subscribers[kind].append(callback)

    def is_command(self, event):
        return event.type == self.command_event_id

    def remove_subscriber(self, callback, kind=None):
        if kind is None:
            kind = self.command_event_id
        self.subscribers[kind].remove(callback)

    def compare(self, evt, commands=None, cancel=False, **attributes):
        if self.is_command(evt):
            self.add_cancel_flag_to_attributes(attributes, cancel)
        if commands is not None and not isinstance(commands, list):
            commands = [commands]
        if commands is not None:
            if not self.command_in_list(evt, commands):
                return False
        return all(key in evt.dict and evt.dict[key] == value for \
                   key, value in attributes.iteritems())

    def add_cancel_flag_to_attributes(self, attributes, cancel):
        attributes[self.cancel_flag_key] = cancel

    def command_in_list(self, evt, commands):
        return self.get_command_attribute(evt) in commands

    def get_command_attribute(self, evt):
        return evt.dict[self.command_key]

    def post(self, command=None, cancel=False, **attributes):
        attributes[self.command_key] = command
        self.add_cancel_flag_to_attributes(attributes, cancel)
        post(Event(self.command_event_id, attributes))
18.97.9.170
18.97.9.170
18.97.9.170
 
January 23, 2021

I wanted to document this chat-controlled robot I made for Babycastles' LOLCAM📸 that accepts a predefined set of commands like a character in an RPG party 〰 commands like walk, spin, bash, drill. It can also understand donut, worm, ring, wheels, and more. The signal for each command is transmitted as a 24-bit value over infrared using two Arduinos, one with an infrared LED, and the other with an infrared receiver. I built the transmitter circuit, and the receiver was built into the board that came with the mBot robot kit. The infrared library IRLib2 was used to transmit and receive the data as a 24-bit value.


fig. 1.1: the LEDs don't have much to do with this post!

I wanted to control the robot the way the infrared remote that came with the mBot controlled it, but the difference would be that since we would be getting input from the computer, it would be like having a remote with an unlimited amount of buttons. The way the remote works is each button press sends a 24-bit value to the robot over infrared. Inspired by Game Boy Advance registers and tracker commands, I started thinking that if we packed multiple parameters into the 24 bits, it would allow a custom move to be sent each time, so I wrote transmitter and receiver code to process commands that looked like this:

bit
name
description
00
time
multiply by 64 to get duration of command in ms
01
02
03
04
left
multiply by 16 to get left motor power
05
06
07
08
right
multiply by 16 to get right motor power
09
10
11
12
left sign
0 = left wheel backward, 1 = left wheel forward
13
right sign
0 = right wheel forward, 1 = right wheel backward
14
robot id
0 = send to player one, 1 = send to player two
15
flip
negate motor signs when repeating command
16
repeats
number of times to repeat command
17
18
19
delay
multiply by 128 to get time between repeats in ms
20
21
22
23
swap
swap the motor power values on repeat
fig 1.2: tightly stuffed bits

The first command I was able to send with this method that seemed interesting was one that made the mBot do a wheelie.

$ ./send_command.py 15 12 15 1 0 0 0 7 0 1
sending 0xff871fcf...


fig 1.3: sick wheels

A side effect of sending the signal this way is any button on any infrared remote will cause the robot to do something. The star command was actually reverse engineered from looking at the code a random remote button sent. For the robot's debut, it ended up with 15 preset commands (that number is in stonks 📈). I posted a highlights video on social media of how the chat controls turned out.

This idea was inspired by a remote frog tank LED project I made for Ribbit's Frog World which had a similar concept: press a button, and in a remote location where 🐸 and 🐠 live, an LED would turn on.


fig 2.1: saying hi to froggo remotely using an LED

😇 The transmitter and receiver Arduino programs are available to be copied and modified 😇