#!/usr/bin/python

# Rocket Land Launch
# "A gracious spring, turned to blood-ravenous autumn" - Rihaku,
# Lament of the Frontier Guard

from os import environ
from os.path import join
from random import randint, randrange, choice, random, uniform, shuffle
from math import tan, radians, ceil

from pygame import init, Surface, transform, PixelArray
from pygame.time import get_ticks, wait
from pygame.event import get
from pygame.display import set_mode, flip, set_caption
from pygame.mouse import set_visible
from pygame.image import load
from pygame.draw import polygon, aaline, circle
from pygame.locals import *

class Between:

    resolution = (640, 480)
    target_frame_duration = 40

    def __init__(self):
        self.quit_queued = False
        self.duration = 0
        init()
        set_visible(False)
        set_caption("Divine Remains Holds Domain")
        set_caption("Desert of Utility")
        set_caption("Involution")
        self.set_screen()
        self.characters = Characters(self)
        self.title = Title(self)
        self.field = Field(self)
        self.title.activate()
        self.last_ticks = get_ticks()
        self.reset()

    def reset(self):
        self.characters.reset()
        self.title.reset()
        self.field.reset()

    def run(self):
        while True:
            self.maintain_framerate()
            self.dispatch_events()
            if self.quit_queued:
                break
            self.title.update()
            self.field.update()
            flip()

    def maintain_framerate(self):
        while self.duration < self.target_frame_duration:
            wait(2)
            ticks = get_ticks()
            self.duration += ticks - self.last_ticks
            self.last_ticks = ticks
        self.duration -= self.target_frame_duration

    def dispatch_events(self):
        for event in get():
            if event.type == KEYDOWN:
                key = event.key
                if key == K_F11:
                    self.set_screen(True)
                elif key == K_F8:
                    self.reset()
                elif key == K_ESCAPE:
                    self.quit()
                elif self.title.active and key in (K_UP, K_DOWN):
                    self.title.change_character(key == K_UP)
                elif self.title.active and key == K_RETURN:
                    self.title.deactivate()
                    self.field.activate()
                    self.field.start_level()
            elif event.type == QUIT:
                self.quit()

    def set_screen(self, toggle_fullscreen=False):
        flags = 0
        if toggle_fullscreen:
            flags = self.screen.get_flags() ^ FULLSCREEN
        self.screen = set_mode(self.resolution, flags)

    def quit(self):
        self.quit_queued = True


class Child:

    def __init__(self, parent):
        self.parent = parent
        self.set_root()
        self.set_screen()

    def set_root(self):
        node = self.parent
        while not isinstance(node, Between):
            node = node.parent
        self.root = node

    def set_screen(self):
        self.screen = self.root.screen


class Characters(Child, list):

    folder = join("resource", "img", "character")
    paths = "h-Hh", "6oF", "Bag"

    def __init__(self, parent):
        Child.__init__(self, parent)
        list.__init__(self, (Character(self, join(self.folder, path)) for \
                             path in self.paths))

    def reset(self):
        self.current_index = 1
        self.parent.field.jumper.set_surface()

    def shift_index(self, decrease=False):
        step = -1 if decrease else 1
        self.current_index += step
        if self.current_index == len(self):
            self.current_index = 0
        elif self.current_index < 0:
            self.current_index = len(self) - 1
        self.parent.field.jumper.set_surface()

    def get_selected_character(self):
        return self[self.current_index]


class Character(Child):

    def __init__(self, parent, path):
        Child.__init__(self, parent)
        self.mono_surface = load(join(path, "mono.png")).convert_alpha()
        self.large_surface = load(join(path, "large.png")).convert_alpha()
        self.mini_surface = load(join(path, "mini.png")).convert_alpha()

    def is_selected_character(self):
        return self == self.parent.get_selected_character()


class Animation(Child):

    def __init__(self, parent, interval):
        Child.__init__(self, parent)
        self.interval = interval
        self.playing = False

    def play(self):
        self.playing = True
        self.last_ticks = get_ticks()
        self.frame_duration = 0

    def stop(self):
        self.playing = False

    def update(self):
        if self.playing:
            self.frame_duration += get_ticks() - self.last_ticks
            if self.frame_duration >= self.interval:
                self.frame_duration -= self.interval
                self.advance_frame()
            self.last_ticks = get_ticks()


class Title(Animation):

    color_components = (0, 80, 70), (0, 60, 60), (0, 90, 80)
    interval_range = 0, 120
    interval_change_rate = .005
    indicator_colors = (Color(*components) for components in \
                        ((255, 255, 0), (255, 0, 255), (0, 255, 255),
                         (255, 192, 87)))

    def __init__(self, parent):
        Animation.__init__(self, parent, self.interval_range[0])
        self.background_index = 0
        self.set_backgrounds()
        rects = self.character_rects = []
        characters = self.parent.characters
        for ii, character in enumerate(characters):
            rect = character.large_surface.get_rect()
            rect.center = self.screen.get_width() / 2, \
                          int(float(ii + 1) / (len(characters) + 1) * \
                              self.screen.get_height())
            rects.append(rect)
        indicator_surfaces = self.indicator_surfaces = []
        rect = self.indicator_rect = Rect(self.screen.get_width() / 3, 0, 22,
                                          23)
        for color in self.indicator_colors:
            surface = Surface(rect.size)
            surface.set_colorkey((0, 0, 0))
            polygon(surface, color, ((0, 0), (rect.w - 1, rect.h / 2 - 1),
                                     (0, rect.h - 1)))
            indicator_surfaces.append(surface)
        self.indicator_surfaces_index = 0

    def set_backgrounds(self):
        backgrounds = self.backgrounds = []
        tiles = []
        size = 4
        colors = []
        for h, s, l in self.color_components:
            color = Color(0, 0, 0)
            color.hsla = h, s, l, 100
            colors.append(color)
        for ii in xrange(len(colors)):
            tile = Surface((size, size))
            for x in xrange(size):
                for y in xrange(size):
                    if not (x + y) % 2:
                        color = colors[ii]
                    elif (x + y) % 4 == 1:
                        color = colors[(ii + 1) % len(colors)]
                    else:
                        color = colors[(ii + 2) % len(colors)]
                    tile.set_at((x, y), color)
            surface = Surface(self.screen.get_size())
            for x in xrange(0, surface.get_width(), size):
                for y in xrange(0, surface.get_height(), size):
                    surface.blit(tile, (x, y))
            backgrounds.append(surface)

    def reset(self):
        self.place_indicator()
        self.activate()

    def place_indicator(self):
        self.indicator_rect.centery = self.\
                                      character_rects[self.parent.characters.\
                                                      current_index].centery

    def activate(self):
        self.active = True
        self.play()

    def deactivate(self):
        self.active = False

    def advance_frame(self):
        self.background_index += 1
        if self.background_index == len(self.backgrounds):
            self.background_index = 0

    def change_character(self, decrement=False):
        self.parent.characters.shift_index(decrement)
        self.place_indicator()

    def update(self):
        if self.active:
            if random() < self.interval_change_rate:
                self.interval = randint(*self.interval_range)
            Animation.update(self)
            self.screen.blit(self.backgrounds[self.background_index], (0, 0))
            for ii, character in enumerate(self.parent.characters):
                if character.is_selected_character():
                    surface = character.large_surface
                else:
                    surface = character.mono_surface
                self.screen.blit(surface, self.character_rects[ii])
            self.indicator_surfaces_index += 1
            if self.indicator_surfaces_index == len(self.indicator_surfaces):
                self.indicator_surfaces_index = 0
            self.screen.blit(self.\
                             indicator_surfaces[self.indicator_surfaces_index],
                             self.indicator_rect)


class Level:

    def __init__(self, pad_width_range, pad_speed_range, pad_gap_range,
                 room_height):
        self.pad_width_range = pad_width_range
        self.pad_speed_range = pad_speed_range
        self.pad_gap_range = pad_gap_range
        self.room_height = room_height

    def generate_pad_parameters(self):
        return tuple((uniform(*limits) for limits in (self.pad_width_range,
                                                      self.pad_speed_range,
                                                      self.pad_gap_range)))


class Field(Child):

    levels = Level((25, 40), (.75, 1), (52, 72), 16), \
             Level((18, 28), (1.2, 1.5), (58, 80), 45), \
             Level((4, 12), (8, 11), (100, 150), 360)

    def __init__(self, parent):
        Child.__init__(self, parent)
        self.background = Background(self)
        self.road = Road(self)
        self.pit = Pit(self)
        self.room = Room(self)
        self.jumper = Jumper(self)

    def reset(self):
        self.level_index = 0
        self.deactivate()

    def deactivate(self):
        self.active = False

    def activate(self):
        self.active = True
        self.pit.play()
        self.road.fire.play()

    def get_current_level(self):
        return self.levels[self.level_index]

    def start_level(self):
        self.background.paint()
        pad_color = self.pad_color = Color(0, 0, 0)
        pad_color.hsla = randrange(0, 360), 100, 32, 100
        pad_border_color = self.pad_border_color = Color(0, 0, 0)
        pad_border_color.hsla = randrange(0, 360), 60, 86, 100
        self.road.populate()
        self.room.place()
        self.jumper.drop()

    def update(self):
        if self.active:
            self.background.update()
            self.pit.update()
            self.road.update()
            self.room.update()
            self.jumper.update()


class Background(Child):

    tile_size = 16
    tile_count = 32
    tile_color_range = 0, 120
    blend = BLEND_RGB_ADD
    segment_sizes = [.1, .15, .25, .33]
    foreground_saturation_range = 80, 80
    foreground_lightness_range = 70, 70
    foreground_hue_offset_range = 4, 30
    mask_speed = 1

    def __init__(self, parent):
        Child.__init__(self, parent)
        self.mask_x = 0
        self.mask = Surface(self.screen.get_size())
        self.foreground = Surface(self.screen.get_size())

    def paint(self):
        self.fill_mask()
        self.fill_foreground()

    def fill_mask(self):
        self.set_tiles()
        mask = self.mask
        for x in xrange(0, mask.get_width(), self.tile_size):
            for y in xrange(0, mask.get_height(), self.tile_size):
                mask.blit(choice(self.tiles), (x, y))

    def set_tiles(self):
        self.tiles = tiles = []
        for _ in xrange(self.tile_count):
            size = self.tile_size
            tile = Surface((size, size))
            palette = self.get_palette()
            window = Rect(0, 0, size / 2, size / 2)
            for x in xrange(0, size, window.w):
                for y in xrange(0, size, window.h):
                    window.topleft = x, y
                    tile.fill(palette[(x + y) % 2], window)
            tiles.append(tile)

    def get_palette(self):
        return self.get_tile_color(), self.get_tile_color()

    def get_tile_color(self):
        color = [0, 0, 0]
        color[randint(0, 2)] = randint(*self.tile_color_range)
        return color

    def fill_foreground(self):
        foreground = self.foreground
        rect = foreground.get_rect()
        x_intervals = [0]
        total = 0
        shuffle(self.segment_sizes)
        for size in self.segment_sizes:
            interval = int(size * rect.w)
            x_intervals.append(interval + total)
            total += interval
        x_intervals.append(rect.w)
        interval_index = 0
        base_hue = randrange(0, 360)
        saturation = randint(*self.foreground_saturation_range)
        lightness = randint(*self.foreground_lightness_range)
        next_base_color = self.get_foreground_color(base_hue, saturation,
                                                    lightness)
        for x in xrange(rect.w):
            if x >= x_intervals[interval_index]:
                interval_index += 1
                base_color = next_base_color
                next_base_color = self.get_foreground_color(base_color.hsla[0],
                                                            saturation,
                                                            lightness)
            bh = base_color.hsla[0]
            nh = next_base_color.hsla[0]
            if nh < bh:
                difference = 360 - bh + nh
            else:
                difference = nh - bh
            hue = int(bh + difference * \
                      ((x - x_intervals[interval_index - 1]) / \
                       float(x_intervals[interval_index] - \
                             x_intervals[interval_index - 1]))) % 360
            color = Color(0, 0, 0)
            color.hsla = [hue] + map(int, base_color.hsla[1:])
            foreground.fill(color, (x, 0, 1, rect.h))

    def get_foreground_color(self, base, saturation, lightness):
        color = Color(0, 0, 0)
        hue = (base + randint(*self.foreground_hue_offset_range)) % 360
        color.hsla = hue, saturation, lightness, 100
        return color

    def update(self):
        self.mask_x -= self.mask_speed
        if self.mask_x < -self.screen.get_width():
            self.mask_x = 0
        self.screen.blit(self.foreground, (0, 0))
        self.screen.blit(self.mask, (self.mask_x, 0), None, self.blend)
        self.screen.blit(self.mask, (self.mask_x + self.screen.get_width(), 0),
                         None, self.blend)


class Road(Child):

    def __init__(self, parent):
        Child.__init__(self, parent)
        self.fire = Fire(self)
        self.pads = Pads(self)

    def populate(self):
        self.pads.populate()

    def update(self):
        self.fire.update()
        self.pads.update()


class Fire(Animation):

    frame_count = 128
    tile_path = join("resource", "img", "fire.png")
    speed = 1
    height = 20

    def __init__(self, parent):
        Animation.__init__(self, parent, 0)
        self.frame_index = 0
        base_tile = load(self.tile_path).convert()
        self.tile_height = base_tile.get_height()
        frames = self.frames = []
        frame_count = self.frame_count
        for ii in xrange(frame_count):
            tile = base_tile.copy()
            pixels = PixelArray(tile)
            for x in xrange(len(pixels)):
                for y in xrange(len(pixels[0])):
                    color = Color(*tile.unmap_rgb(pixels[x][y]))
                    h, s, l, a = color.hsla
                    color.hsla = int((h + ii * 360.0 / frame_count) % 360), \
                                 max(0, s - 10), min(100, l + 10), a
                    pixels[x][y] = color
            del pixels
            tr = tile.get_rect()
            frame = Surface((self.screen.get_width(),
                             tr.h * (self.height / tr.h + 2)), SRCALPHA)
            for x in xrange(0, frame.get_width(), tr.w):
                for y in xrange(0, frame.get_height(), tr.h):
                    frame.blit(tile, (x, y))
            frames.append(frame)
        window_rect = self.window_rect = Rect(0, self.screen.get_height() - \
                                              self.height,
                                              self.screen.get_width(),
                                              self.height)
        self.rect = self.frames[0].get_rect()
        self.rect.bottom = window_rect.bottom

    def advance_frame(self):
        self.frame_index += 1
        if self.frame_index == len(self.frames):
            self.frame_index = 0

    def get_current_frame(self):
        return self.frames[self.frame_index]

    def update(self):
        Animation.update(self)
        self.rect.bottom += self.speed
        if self.rect.bottom == self.window_rect.bottom + self.tile_height:
            self.rect.bottom = self.window_rect.bottom
        self.screen.set_clip(self.window_rect)
        self.screen.blit(self.get_current_frame(), self.rect)
        self.screen.set_clip(None)


class Pads(Child, list):

    def __init__(self, parent):
        Child.__init__(self, parent)

    def populate(self):
        list.__init__(self, [])
        x = -20
        while x < self.screen.get_width():
            width, speed, self.gap = self.parent.parent.get_current_level().\
                                     generate_pad_parameters()
            self.append(Pad(self, width, speed))
            self[-1].x = x
            x += self.gap + width

    def update(self):
        self.retire()
        for pad in self:
            pad.update()
        if self.screen.get_width() - self[-1].rect.right >= self.gap:
            width, speed, self.gap = self.parent.parent.get_current_level().\
                                     generate_pad_parameters()
            self.append(Pad(self, width, speed))

    def retire(self):
        while self[0].rect.right < 0:
            self.pop(0)


class Pad(Child):

    height = 6

    def __init__(self, parent, width, speed):
        Child.__init__(self, parent)
        self.speed = speed
        surface = self.surface = Surface((width, self.height))
        rect = self.rect = surface.get_rect()
        field = self.parent.parent.parent
        rect.bottomleft = self.screen.get_width(), \
                          field.road.fire.window_rect.top
        surface.fill(field.pad_color)
        surface.fill(field.pad_border_color, (0, 0, rect.w, 2))
        surface.fill(field.pad_border_color, (0, 0, 2, rect.h))
        surface.fill(field.pad_border_color, (rect.w - 2, 0, 2, rect.h))
        self.x = rect.left

    def update(self):
        self.x -= self.speed
        self.rect.left = int(self.x)
        self.screen.blit(self.surface, self.rect)


class Pit(Animation):

    frame_count = 20
    radius = 8
    alpha = 220

    def __init__(self, parent):
        Animation.__init__(self, parent, 600)
        self.frame_index = 0
        background_frames = self.background_frames = []
        foreground_frames = self.foreground_frames = []
        radius = self.radius
        for ii in xrange(self.frame_count):
            background_frame = Surface((radius * 2, self.screen.get_height()))
            background_frame.set_colorkey((0, 0, 0))
            foreground_frame = background_frame.copy()
            color = Color(0, 0, 0)
            color.hsla = int(ii * 360.0 / self.frame_count), 100, 60, 100
            for y in xrange(radius, background_frame.get_height(), radius * 2):
                # circle(background_frame, color, (radius, y), radius)
                color.hsla = [(color.hsla[0] + 30) % 360] + list(color.hsla[1:])
                circle(foreground_frame, color, (radius, y), radius - 4)
            background_frame.set_alpha(self.alpha)
            foreground_frame.set_alpha(self.alpha)
            background_frames.append(background_frame)
            foreground_frames.append(foreground_frame)
        rect = self.rect = background_frame.get_rect()
        rect.right = self.screen.get_rect().right - 2

    def advance_frame(self):
        self.frame_index += 1
        if self.frame_index == len(self.background_frames):
            self.frame_index = 0

    def update(self):
        Animation.update(self)
        self.screen.blit(self.background_frames[self.frame_index], self.rect)
        self.screen.blit(self.foreground_frames[self.frame_index], self.rect)


class Room(Child):

    image_path = join("resource", "img", "cliff")

    def __init__(self, parent):
        Child.__init__(self, parent)
        self.set_surfaces()
        self.close()

    def set_surfaces(self):
        self.closed_surface = load(join(self.image_path,
                                        "closed.png")).convert_alpha()
        self.open_surface = load(join(self.image_path,
                                      "open.png")).convert_alpha()
        rect = self.rect = self.closed_surface.get_rect()
        rect.right = self.screen.get_rect().right

    def close(self):
        self.closed = True
        self.set_active_surface()

    def set_active_surface(self):
        if self.closed:
            self.active_surface = self.closed_surface
        else:
            self.active_surface = self.open_surface

    def open(self):
        self.closed = False
        self.set_active_surface()

    def place(self):
        self.rect.bottom = self.screen.get_height() - \
                           self.parent.get_current_level().room_height

    def update(self):
        self.screen.blit(self.active_surface, self.rect)


class Jumper(Child):

    hover_location = 38, 300
    hover_length = 3000

    def __init__(self, parent):
        Child.__init__(self, parent)
        self.blink = Blink(self)

    def set_surface(self):
        self.surface = self.parent.parent.characters.get_selected_character().\
                       mini_surface
        self.rect = self.surface.get_rect()

    def drop(self):
        self.blink.play()
        self.hover_remaining = self.hover_length
        self.last_ticks = get_ticks()
        self.velocity = [0, 0]
        self.rect.center = self.hover_location
        self.precise_location = list(self.rect.topleft)

    def update(self):
        if self.hover_remaining > 0:
            self.hover_remaining -= get_ticks() - self.last_ticks
            if self.hover_remaining <= 0:
                self.blink.stop()
                self.velocity = [0, -5]
            else:
                self.last_ticks = get_ticks()
        self.blink.update()
        self.precise_location[0] += self.velocity[0]
        self.precise_location[1] -= self.velocity[1]
        self.rect.topleft = map(int, self.precise_location)
        if self.blink.visible:
            self.screen.blit(self.surface, self.rect)


class Blink(Animation):

    def __init__(self, parent):
        Animation.__init__(self, parent, 300)
        self.stop()

    def advance_frame(self):
        self.visible = not self.visible

    def stop(self):
        Animation.stop(self)
        self.visible = True


if __name__ == "__main__":
    environ["SDL_VIDEO_CENTERED"] = "1"
    Between().run()
216.73.216.2
216.73.216.2
216.73.216.2
 
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 😇