This video is related to Figure 11.3 in the book. Each point of the object can be tracked by the eye as it smoothly moves across the screen. There are no rough or "jagged" points in the arc of movement.
Pop In Arc
This video is also related to Figure 11.3 in the book. It shows a pop in the arc, occurring near the beginning of the video. After this pop, the movement continues along its original (and smooth) path, but the damage has been done- the animation now has a pop in it, that distracts the eye.
Pop In Spacing
This is the final video related to Figure 11.4 in the book. Here we see pops in the spacing, when the spacing suddenly (and without reason) increases, before once again decreasing. These rough spots in the spacing are serious distractions from the flow of the animation.
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