Yes actually, particle motion is quantized on the planck scale, that is, snapped to the grid. That's why it's called quantum physics. Modern theories even have

Yes actually, particle motion is quantized on the planck scale, that is, snapped to the grid. That's why it's called quantum physics. Modern theories even have it that there are no particles, rather, excitations of various quantum fields. So what we consider a discrete photon particle with a location (x,y) would actually not be an individual particle and would be more like: electromagnetic_field[y][x] = "excited" in a big (presumably infinite) grid.