pocket-friends/pocket_friends/elements/surface.py

"""Module to aid in the drawing of surfaces to make switching from one screen to another easier."""
import pygame
from ..io.input_handler import InputHandler


class GameSurface(pygame.Surface):
    """
    Class to be used as the backbone of all game surfaces.
    Attributes:
        running (bool): Boolean to tell whether the surface is running or not.
        next_surface (:obj:`str`): What the next surface should be after halting.
        resource_dir (:obj:`str`): The path of the game's main resource directory.
        game_fps (int): How many frames per second the game will run at.
        additional_args (dict): Additional arguments to send to the next surface after halting.
        bg (:obj:`pygame.Surface`): The background of the surface.
    """
    def __init__(self, game_res, resources_dir, game_fps):
        """
        Create a GameSurface object.
        Args:
            game_res (int): The internal resolution of the surface.
            resources_dir (:obj:`str`): The path of the game's main resource directory.
            game_fps: (int): How many frames per second the game will run at.
        """
        super().__init__(game_res, pygame.SRCALPHA)
        self.running = True
        self.next_surface = None
        self.resource_dir = resources_dir
        self._clock = pygame.time.Clock()
        self.game_fps = game_fps
        self._input_handler = InputHandler(self._clock)
        self.additional_args = {}

        self.bg = pygame.image.load(self.resource_dir + '/images/bg.png').convert_alpha()
        self.sprites = pygame.sprite.Group()

    def preprocess(self):
        """
        Advance the surface by one frame and draw the background.
        """
        self._clock.tick(self.game_fps)

        self.blit(self.bg, (0, 0))
        self.sprites.update()
        self.sprites.draw(self)

        self._input_handler.update()