This is a wall where little people live that plays sounds. The little people run around inside the wall, oblivious to us.
However, when things like mushrooms, trees, and long sticks of ice are attached to the wall, the little people notice them and jump on. Depending on the type of object that has been attached to the wall, the little people will slide, jump, or climb on. Attach various kinds of objects to the wall, and the little people will play with delight.
Smiley face seeds come falling down from above. When these seeds hit the mushrooms and other things on the wall, different tones are played, depending on the type object they hit. Also, depending on the height of the things that have been attached to the wall, these tones will change in pitch.
Attach mushrooms and so on to different parts of the wall, and the wall will start playing music.
Reference : https://www.teamlab.art/jp/ew/kobitowall/
- Smoothed Particle Hydrodynamics