Миллион нот за пять минут?

Каких усилий требует подобное видео на Юнити?

Чисто с технической стороны

Как долго такое кодить? Как это кодить? На чем это рендерить?

Кому лень смотреть - там "визуализация" Эдварда Грига "В пещере горного короля" и почти миллион "отработанных нот" с физической симуляцией.

Со слов автора:
Fun facts: - Thirty two gigs of RAM was not enough to hold the required game objects in the scene, so I upgraded to 64 just to make this video. - Each frame was taking so long to load it was causing my GPU drivers to time out and crash. I had to edit a registry value called TdrDelay to resolve this. - The final image sequence recording was over 100GB. Good luck youtube compression haha. - My computer was rendering nonstop for over a week to capture the ray traced portion before the crash.