paddle.py

import pygame
import pymunk
import colors
import const

from pygame.locals import *
from pymunk import Vec2d
from entity import Entity

class Paddle(Entity):

    DIMENSIONS = (20, 80)

    def __init__(self, space, pos):
        image = self._get_base_image()

        super(Paddle, self).__init__(image=image, space=space, mass=500,
                                     inertia=pymunk.inf, x=pos[0], y=pos[1])

        self.shape = pymunk.Poly.create_box(self.body, Paddle.DIMENSIONS)
        self.shape.elasticity = 1.
        self.space.add(self.body, self.shape)

    def _get_base_image(self):
        surf = pygame.Surface(Paddle.DIMENSIONS)
        surf.fill(colors.BLUE)
        return surf

    def update(self, dt=0):
        super(Paddle, self).update(dt)
        self.body.velocity = self._handle_input()

    def _handle_input(self):
        keys = pygame.key.get_pressed()
        if keys[K_UP]: return Vec2d(0, 200)
        elif keys[K_DOWN]: return Vec2d(0, -200)
        else: return Vec2d(0, 0)