import numpy as np

class Camera(object):
    def __init__(self, size = (800, 600), film_size = (0.035, 0.024), focal_length=0.05):
        width, height = size

        grid = []
        for i, x in enumerate(np.linspace(-film_size[0]/2, film_size[0]/2, width)):
            for j, z in enumerate(np.linspace(-film_size[1]/2, film_size[1]/2, height)):
                grid.append((x,0,z))

        self.grid = np.array(grid)
        self.grid += (0,focal_length,0)

        self.focal_point = np.zeros(3)

    def position(self, position):
        self.grid += position
        self.focal_point += position

    def get_pixels(self):
        return self.grid, self.focal_point-self.grid