apples.py

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import curses
import sys

from pycolab import ascii_art
from pycolab import human_ui
from pycolab import things as plab_things
from pycolab.prefab_parts import sprites as prefab_sprites

from six.moves import xrange  # pylint: disable=redefined-builtin

LEVELS = [
    # the only level
    [
        '##############################',
        '#      .......        A     E#',
        '###############   ############',
        '#         **              *  #',
        '##############################',
    ]
]

FG_COLOURS = {
    'A': (999, 500, 0),    # Player wears an orange jumpsuit.
    '#': (700, 700, 700),  # Normal wall, bright grey.
    ' ': (200, 200, 200),  # Floor.
    '.': (0, 250, 0),  # Spikes.
    '*': (0, 200, 200),  # Berries.
    'E': (0, 200, 200), # Exit!
}

BG_COLOURS = {
    'A': (200, 200, 200),
    '#': (800, 800, 800),
    '.': (100, 300, 100),
    '*': (999, 800, 800),
    ' ': (200, 200, 200),
    'E': (999, 800, 800),
}

class PlayerSprite(prefab_sprites.MazeWalker):
    """The player

    parent class handles basic movement + collision detection. The
    special drape handles the consumption of berries?
    """

    def __init__(self, corner, position, character):
        super(PlayerSprite, self).__init__(
            corner, position, character, impassable='#')

    def update(self, actions, board, layers, backdrop, things, the_plot):
        del backdrop  # Unused.

        # Handles basic movement
        if actions == 0:  # go upward?
            self._north(board, the_plot)
        elif actions == 1:  # go downward?
            self._south(board, the_plot)
        elif actions == 2:  # go leftward?
            self._west(board, the_plot)
        elif actions == 3:  # go rightward?
            self._east(board, the_plot)
        elif actions == 9:  # quit?
            the_plot.terminate_episode()

        # Did we walk into a spike? If so, we win!
        if layers['.'][self.position]:
            the_plot.add_reward(-1)
        
        # Did we walk into a berry? If so, we win!
        if layers['*'][self.position]:
            the_plot.add_reward(10)
        
        # Did we walk into an exit? If so, we win!
        if layers['E'][self.position]:
            the_plot.terminate_episode()


def make_game(level_idx):
    """level_idx has to be 0, because we only have 1 level
    """
    return ascii_art.ascii_art_to_game(
        art=LEVELS[level_idx],
        what_lies_beneath=' ',
        sprites={'A': PlayerSprite},
        update_schedule=[['A']],
        z_order=['A'])


def main(argv=()):
    game = make_game(int(argv[1]) if len(argv) > 1 else 0)

    ui = human_ui.CursesUi(
        keys_to_actions={
            # Basic movement.
            curses.KEY_UP: 0,
            curses.KEY_DOWN: 1,
            curses.KEY_LEFT: 2,
            curses.KEY_RIGHT: 3,
            -1: 4,  # Do nothing.
            # Quit game.
            'q': 9,
            'Q': 9,
        },
        delay=50,
        colour_fg=FG_COLOURS,
        colour_bg=BG_COLOURS)

    ui.play(game)

if __name__ == "__main__":
    main(sys.argv)