in sampling.py [0:0]
def sampling_func(y, **kwargs):
h, w = kwargs['size']
level_dimensions = kwargs['level_dimensions']
level = kwargs['level']
_random_offset_scale = 0.5
xoffset = randint(-w, w) * _random_offset_scale
yoffset = randint(-h, h) * _random_offset_scale
slide_width, slide_height = level_dimensions[level]
xmin, ymin = randint(int(w / 2 - xoffset), slide_width - w), randint(int(h / 2 - yoffset), slide_height - h)
return int(xmin - w / 2 + xoffset), int(ymin - h / 2 + yoffset)