# Path: luma/core/framebuffer.py
# class full_frame(object):
#     """
#     Always renders the full frame every time. This is slower than
#     :py:class:`diff_to_previous` as there are generally more
#     pixels to update on every render, but it has a more consistent render time.
#     Not all display drivers may be able to use the differencing framebuffer, so
#     this is provided as a drop-in replacement.
#     """
# 
#     def __init__(self, **kwargs):
#         """
#         Accepts any args but does nothing
#         """
# 
#     def redraw(self, image):
#         """
#         Yields the full image for every redraw.
# 
#         :param image: The image to render.
#         :type image: PIL.Image.Image
#         :returns: Yields a single tuple of an image and the bounding box for that image
#         :rtype: Generator[Tuple[PIL.Image.Image, Tuple[int, int, int, int]]]
#         """
#         yield image, (0, 0) + image.size
# 
# class diff_to_previous(object):
#     """
#     Compare the current frame to the previous frame and tries to calculate the
#     differences: this will either yield nothing for a perfect match or else
#     the iterator will yield one or more tuples comprising of the image part that
#     changed along with the bounding box that describes the areas that are different,
#     up to the size of the entire image.
# 
#     The image data for the difference is then be passed to a device for
#     rendering just those small changes. This can be very quick for small screen
#     updates, but suffers from variable render times, depending on the changes
#     applied. The :py:class:`luma.core.sprite_system.framerate_regulator` may be
#     used to counteract this behavior however.
# 
#     :param num_segments: The number of segments to partition the image into. This
#         generally must be a square number (1, 4, 9, 16, ...) and must be able to
#         segment the image entirely in both width and height. i.e setting to 9 will
#         subdivide the image into a 3x3 grid when comparing to the previous image.
#     :type num_segments: int
#     :param debug: When set, draws a red box around each changed image segment to
#         show the area that changed. This is obviously destructive for displaying
#         the actual image, but intends to show where the tracked changes are.
#     :type debug: boolean
#     """
# 
#     def __init__(self, num_segments=4, debug=False):
#         self.__debug = debug
#         self.__n = int(sqrt(num_segments))
#         assert num_segments >= 1 and num_segments == self.__n ** 2
#         self.prev_image = None
# 
#     def redraw(self, image):
#         """
#         Calculates the difference from the previous image, returning a sequence of
#         image sections and bounding boxes that changed since the previous image.
# 
#         .. note::
#             the first redraw will always render the full frame.
# 
#         :param image: The image to render.
#         :type image: PIL.Image.Image
#         :returns: Yields a sequence of images and the bounding box for each segment difference
#         :rtype: Generator[Tuple[PIL.Image.Image, Tuple[int, int, int, int]]]
#         """
#         image_width, image_height = image.size
#         segment_width = int(image_width / self.__n)
#         segment_height = int(image_height / self.__n)
#         assert segment_width * self.__n == image_width, "Total segment width does not cover full image width"
#         assert segment_height * self.__n == image_height, "Total segment height does not cover full image height"
# 
#         changes = 0
# 
#         # Force a full redraw on the first frame
#         if self.prev_image is None:
#             changes += 1
#             yield image, (0, 0) + image.size
# 
#         else:
#             for y in range(0, image_height, segment_height):
#                 for x in range(0, image_width, segment_width):
#                     bounding_box = (x, y, x + segment_width, y + segment_height)
#                     prev_segment = self.prev_image.crop(bounding_box)
#                     curr_segment = image.crop(bounding_box)
#                     segment_bounding_box = ImageChops.difference(prev_segment, curr_segment).getbbox()
#                     if segment_bounding_box is not None:
#                         changes += 1
#                         segment_bounding_box_from_origin = (
#                             x + segment_bounding_box[0],
#                             y + segment_bounding_box[1],
#                             x + segment_bounding_box[2],
#                             y + segment_bounding_box[3]
#                         )
# 
#                         image_delta = curr_segment.crop(segment_bounding_box)
# 
#                         if self.__debug:
#                             w, h = image_delta.size
#                             draw = ImageDraw.Draw(image_delta)
#                             draw.rectangle((0, 0, w - 1, h - 1), outline="red")
#                             del draw
# 
#                         yield image_delta, segment_bounding_box_from_origin
# 
#         if changes > 0:
#             self.prev_image = image.copy()


from PIL import Image, ImageDraw
from luma.core.framebuffer import full_frame, diff_to_previous
    assert redraws[0][0] == im1
    assert redraws[0][1] == im1.getbbox()
    assert redraws[0][1] is not None

    # Redraw of same image should return empty changeset
    redraws = list(framebuffer.redraw(im1))
    assert len(redraws) == 0

    # Redraw of new image should return two changesets
    redraws = list(framebuffer.redraw(im2))
    assert len(redraws) == 2

    assert redraws[0][0] == im2.crop((0, 20, 20, 40))
    assert redraws[0][1] == (20, 0, 40, 20)

    assert redraws[1][0] == im2.crop((20, 0, 40, 20))
    assert redraws[1][1] == (0, 20, 20, 40)

    # Redraw of original image should return two changesets
    redraws = list(framebuffer.redraw(im1))
    assert len(redraws) == 2

    assert redraws[0][0] == im1.crop((20, 0, 40, 20))
    assert redraws[0][1] == (20, 0, 40, 20)

    assert redraws[1][0] == im1.crop((0, 20, 20, 40))
    assert redraws[1][1] == (0, 20, 20, 40)


def test_diff_to_previous_debug():

# Path: luma/core/framebuffer.py
# class full_frame(object):
#     """
#     Always renders the full frame every time. This is slower than
#     :py:class:`diff_to_previous` as there are generally more
#     pixels to update on every render, but it has a more consistent render time.
#     Not all display drivers may be able to use the differencing framebuffer, so
#     this is provided as a drop-in replacement.
#     """
# 
#     def __init__(self, **kwargs):
#         """
#         Accepts any args but does nothing
#         """
# 
#     def redraw(self, image):
#         """
#         Yields the full image for every redraw.
# 
#         :param image: The image to render.
#         :type image: PIL.Image.Image
#         :returns: Yields a single tuple of an image and the bounding box for that image
#         :rtype: Generator[Tuple[PIL.Image.Image, Tuple[int, int, int, int]]]
#         """
#         yield image, (0, 0) + image.size
# 
# class diff_to_previous(object):
#     """
#     Compare the current frame to the previous frame and tries to calculate the
#     differences: this will either yield nothing for a perfect match or else
#     the iterator will yield one or more tuples comprising of the image part that
#     changed along with the bounding box that describes the areas that are different,
#     up to the size of the entire image.
# 
#     The image data for the difference is then be passed to a device for
#     rendering just those small changes. This can be very quick for small screen
#     updates, but suffers from variable render times, depending on the changes
#     applied. The :py:class:`luma.core.sprite_system.framerate_regulator` may be
#     used to counteract this behavior however.
# 
#     :param num_segments: The number of segments to partition the image into. This
#         generally must be a square number (1, 4, 9, 16, ...) and must be able to
#         segment the image entirely in both width and height. i.e setting to 9 will
#         subdivide the image into a 3x3 grid when comparing to the previous image.
#     :type num_segments: int
#     :param debug: When set, draws a red box around each changed image segment to
#         show the area that changed. This is obviously destructive for displaying
#         the actual image, but intends to show where the tracked changes are.
#     :type debug: boolean
#     """
# 
#     def __init__(self, num_segments=4, debug=False):
#         self.__debug = debug
#         self.__n = int(sqrt(num_segments))
#         assert num_segments >= 1 and num_segments == self.__n ** 2
#         self.prev_image = None
# 
#     def redraw(self, image):
#         """
#         Calculates the difference from the previous image, returning a sequence of
#         image sections and bounding boxes that changed since the previous image.
# 
#         .. note::
#             the first redraw will always render the full frame.
# 
#         :param image: The image to render.
#         :type image: PIL.Image.Image
#         :returns: Yields a sequence of images and the bounding box for each segment difference
#         :rtype: Generator[Tuple[PIL.Image.Image, Tuple[int, int, int, int]]]
#         """
#         image_width, image_height = image.size
#         segment_width = int(image_width / self.__n)
#         segment_height = int(image_height / self.__n)
#         assert segment_width * self.__n == image_width, "Total segment width does not cover full image width"
#         assert segment_height * self.__n == image_height, "Total segment height does not cover full image height"
# 
#         changes = 0
# 
#         # Force a full redraw on the first frame
#         if self.prev_image is None:
#             changes += 1
#             yield image, (0, 0) + image.size
# 
#         else:
#             for y in range(0, image_height, segment_height):
#                 for x in range(0, image_width, segment_width):
#                     bounding_box = (x, y, x + segment_width, y + segment_height)
#                     prev_segment = self.prev_image.crop(bounding_box)
#                     curr_segment = image.crop(bounding_box)
#                     segment_bounding_box = ImageChops.difference(prev_segment, curr_segment).getbbox()
#                     if segment_bounding_box is not None:
#                         changes += 1
#                         segment_bounding_box_from_origin = (
#                             x + segment_bounding_box[0],
#                             y + segment_bounding_box[1],
#                             x + segment_bounding_box[2],
#                             y + segment_bounding_box[3]
#                         )
# 
#                         image_delta = curr_segment.crop(segment_bounding_box)
# 
#                         if self.__debug:
#                             w, h = image_delta.size
#                             draw = ImageDraw.Draw(image_delta)
#                             draw.rectangle((0, 0, w - 1, h - 1), outline="red")
#                             del draw
# 
#                         yield image_delta, segment_bounding_box_from_origin
# 
#         if changes > 0:
#             self.prev_image = image.copy()


# Path: tests/test_framebuffer.py
from PIL import Image, ImageDraw
from luma.core.framebuffer import full_frame, diff_to_previous

    assert redraws[0][0] == im1
    assert redraws[0][1] == im1.getbbox()
    assert redraws[0][1] is not None

    # Redraw of same image should return empty changeset
    redraws = list(framebuffer.redraw(im1))
    assert len(redraws) == 0

    # Redraw of new image should return two changesets
    redraws = list(framebuffer.redraw(im2))
    assert len(redraws) == 2

    assert redraws[0][0] == im2.crop((0, 20, 20, 40))
    assert redraws[0][1] == (20, 0, 40, 20)

    assert redraws[1][0] == im2.crop((20, 0, 40, 20))
    assert redraws[1][1] == (0, 20, 20, 40)

    # Redraw of original image should return two changesets
    redraws = list(framebuffer.redraw(im1))
    assert len(redraws) == 2

    assert redraws[0][0] == im1.crop((20, 0, 40, 20))
    assert redraws[0][1] == (20, 0, 40, 20)

    assert redraws[1][0] == im1.crop((0, 20, 20, 40))
    assert redraws[1][1] == (0, 20, 20, 40)


def test_diff_to_previous_debug():

    framebuffer = diff_to_previous(num_segments=4, debug=True)