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Movie D2

In this movie, we again see what happens from D's point of view, as the distance between each bug increases and eventually doubles.

However, this time we cover the plane with a grid. This might make it easier to see the distance and direction that the bugs appear to have moved (from D's viewpoint). However, it is important to bear in mind that, unlike points in the plane, the grid itself does not expand or move - indeed it is somehow fixed to D.

In the movie on the next page, the grid is absent once more, but the P-shape is made more explicit.