This work is a video piece that was exhibited and screened as part of an ambient projection-mapping presentation at the EXPO Hall “Shine Hat” and the Popup Stage East Outside at Expo 2025 Osaka, Kansai. Taking as its motif the “EXPO 2025 Design System” IDs, affectionately known as “Komyaku” at Expo 2025 Osaka, Kansai, and with Kohta Hikichi, a representative member of the team that created it, serving as an advisor, we drew on the expertise in artificial-life ecological systems that HiRai has long been researching to create a real-time video simulation system and visuals. In producing the video, we referenced the design system’s history of being prototyped based on metaballs, and developed a real-time simulator in which the Komyaku behave as if they were alive while retaining the identity of the design itself. By using GPGPU to calculate the interactions among large numbers of Komyaku in real time, we built a system that can be flexibly expanded to support a wide range of possibilities, including interaction and the generation of one-of-a-kind videos. At the Popup Stage East Outside, we also took advantage of the architectural characteristics of a structure in which the projected image is interrupted by support columns, and created visuals that made it look as though each steel beam were packed full of Komyaku. We pursued video production that made the most of the characteristics of the projection surface. The name “Komyaku” naturally spread as a nickname referring to the IDs that make up the design system. Taking into account this derivative, fan-created cultural expansion, this work intentionally uses the term “Komyaku.”

Description: An art piece created as the "Sea Room" at the Museum of Inhomogeneous Nature and People, located within Nagasaki Bana Resort Campground in Bungotakada City, Oita Prefecture, using water-drop projection mapping. By combining a water-drop fountain performance by Water Pearl Co., Ltd. with an ultra-high-speed projector from Tokyo Electron Device Limited, the work achieves precise projection mapping onto a continuous stream of falling water droplets. This new technology, which has been patented internationally, makes it possible to display animations that smoothly move individual water droplets up and down—something that could not be achieved with conventional Water Pearl installations using strobe lighting. These water droplets are real water that can be touched.