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.”

Exhibited at NTT ICC Kids Program “Kimi ( ). Code ( ). Sekai ( ).” This program was an event for children during summer vacation, and this work was also created with elementary school children and younger viewers in mind. Using bubbles, a “boundary” commonly found in nature, as its motif, the work creates a simulation that expresses an ecosystem composed of multilayered enclosed regions. This simulator runs in real time using GPGPU technology, enabling interaction with viewers. Sensors installed at the floor level detect the movements of children, allowing interaction between the artificial ecosystem and the children. In addition, a new projection sheet was installed for this work, and by instructing viewers to step onto it barefoot, the experience was designed so that they could engage with the artificial ecosystem on a life-size scale while feeling the raw texture through the soles of their feet.

Exhibited at PARCO P.O.N.D. 2022. A swarm of artificial lifeforms, each with distinct genes and intelligence, formed groups for their own survival and the preservation of their genes, preying on other species and reproducing through mating; this behavior was simulated in real time using GPGPU technology. The activities of each lifeform produce changes only in their immediate vicinity, but those effects spread through a network of interactions, forming a diverse ecosystem. This work was exhibited on a human-height touch display on the fifth floor of Shibuya PARCO, enabling life-size interaction. The touch display was installed midway along a route traveled by people with a wide range of attributes as they moved through the shops, creating unpredictable encounters between the ecosystem and viewers, while also becoming a place for unexpected communication among viewers mediated by the work. As part of “Katawara,” a project to make artificial life exist alongside everyday life, the simulator was run continuously for more than a week in 2024, and the process was streamed on YouTube Live.