on_grating_masked
=================


.. image:: /_static/generated_stimuli/stimuli.gratings.on_grating_masked.png
   :alt: on_grating_masked stimulus example
   :align: center
   :width: 400px



.. centered:: You can find an interactive version of this example `here <../../../demos/stimuli/gratings/on_grating_masked.html>`__





.. py:function:: stimupy.stimuli.gratings.on_grating_masked(small_grating_params, large_grating_params, mask_size=None, mask_rotation=None)


   Small grating, with a parallelogram-like shape, on a larger grating

   :param small_grating_params: kwargs to generate small grating
   :type small_grating_params: dict
   :param large_grating_params: kwargs to generate larger grating
   :type large_grating_params: dict
   :param mask_size: size (height, width, depth) of parallelogram-like mask in degrees visual angle
   :type mask_size: Sequence[Number, Number, Number], Sequence[Number, Number], Number or None (default)
   :param mask_rotation: rotation of the mask in degree
   :type mask_rotation: float

   :returns: dict with the stimulus (key: "img"),
             mask with integer index for each bar (key: "target_mask"),
             and additional keys containing stimulus parameters
   :rtype: dict[str, Any]

   .. rubric:: References

   White, M. (1981).
       The effect of the nature of the surround on the perceived lightness
       of grey bars within square-wave test grating.
       Perception, 10, 215-230.
       https://doi.org/10.1068/p100215