def METHOD_NAME(self):
    swipe_base = None
    for loca, grid in az.view.grids.items():
        offset = grid.screen2grid([az.config.SCREEN_CENTER])[0].astype(int)
        points = grid.grid2screen(np.add([[0.5, 0], [-0.5, 0], [0, 0.5], [0, -0.5]], offset))
        swipe_base = np.array([np.linalg.norm(points[0] - points[1]), np.linalg.norm(points[2] - points[3])])
        break
    if swipe_base is None:
        logger.critical('Unable to get swipe_base')
        exit(1)
    else:
        return swipe_base