How to make an animated city just by moving lots of white dots at different speeds? Motion parallax.
Video: Emergent City Flyby with Colossus | Best Illusion of the Year Contest
In this super cool video Emergent City Flyby with Colossus, they demonstrated how to make a contemporary animation by moving lots of white dots at different speeds.
Given all objects are moving at the same speed, objects farther away appear to move a shorter amount than objects closer to an observer. For example, when we are on an airplane, the clouds near us will seem to move more visually than the farther. The difference in image motion between objects at different depths is called motion parallax.
We usually see the structure of an object by detecting its edges. However, in the video they used motion parallax to outline the structure without explicit luminance edges or other depth cues.
There are some other interesting and mind-blowing illusion applications in the Best Illusion of the Year Contest 2021. The Phantom Queen used a carefully designed anamorphic camouflage shield to hide an object in one perspective and let it only appears in the mirrored image. Oh La La Box also used a similar technique to make a visually normal box from X-shaped cardboard.