Creating drifting gratings (frame by frame)

[SalvoCalcagno]

According to the information provided at https://alleninstitute.github.io/AllenSDK/_static/examples/nb/brain_observatory_monitor.html, static gratings can be generated using the grating_to_screen method, which depends on allensdk.brain_observatory.stimulus_info.get_spatial_grating.

Following this logic, drifting gratings can be created by generating static gratings with different phases. This can be accomplished using the allensdk.brain_observatory.stimulus_info.get_spatio_temporal_grating method, which accepts a float timepoint (t) and the temporal frequency.

To achieve a correct presentation of the drifting gratings stimulus, it is important to understand how to use the tt parameter. What is the range of t, and how does it vary during the presentation of the stimulus (i.e., at each frame)? My hypothesis is that t is a number between 0 and 1, and its values are spaced on a 1/30 basis. Is this hypothesis correct?