import ctypes

  windowsurface = ctypes.pointer(window.get_surface())
  test_tensor = tf.constant([[[0,0,255]] * 1024] * 512)
  image = tensor_to_surface(test_tensor)
  sdl2.SDL_BlitSurface(image, None, windowsurface, None)
  window.refresh()
  sdl2.SDL_FreeSurface(image)

# TODO: refactor to only do a few pixels at a time because python is really slow
# Keeping this function here in the meantime because it wasn't easy to figure
# out how to write it.
def tensor_to_surface(source):
    shape = source.shape
    height = shape[0]
    width = shape[1]
    surface = sdl2.surface.SDL_CreateRGBSurface(0, width, height, 32, 0, 0, 0, 0)
    pixels = sdl2.ext.pixels2d(surface.contents, False)
    # pixels are 4 bytes: b g r 0
    for y in range(0,height):
        row = source[y]
        d_row = pixels[y]
        for x in range(0,width):
            pixel = row[x]
            d_row[x] = pixel[0] * 65536 + pixel[1] * 256 + pixel[2]
        print(y)
    return surface