Heidi and Super Mario may not seem to have much in common but anime and video game aficionados will detect the signature style of Japanese character designer Yoichi Kotabe in both.
Far from the Swiss Alps, the cherished 19th-century storybook character Heidi has played an unlikely role in the creation of Japan's now booming anime industry.
The story of the little orphan girl who goes to live with her gruff grandfather in the mountains took Japan by storm in the 1970s with the animation series "Alps no Shojo Heidi" ("Heidi: A Girl of the Alps").
Visitors walk through the exhibition titled "Heidi in Japan" showing cartoon boards from the animated series "Heidi."
The 52-part TV show, which became a worldwide hit, marked a turning point in the careers of its creators, including Kotabe.
Heidi also boosted the standing of director Isao Takahata, best known for the animated war film "Grave of the Fireflies", and Hayao Miyazaki, creator of films "Spirited Away" and "My Neighbor Totoro".
'Kawaii'
"The goal was to have a little girl who was 'kawaii', as cute as possible," he told AFP, describing how he had first drawn her with large eyes, a big smile, but also "little braids".
Japanese animator and character designer Yoichi Kotabe looks on behind cartoon boards.
But he said that when he presented his first sketches, a specialist on the 1880 novel by Johanna Spyri pointed out that "Heidi is a five year-old girl who lives in the mountains with her grandfather, who is not very friendly".
Sketching the Swiss Alps
Takahata had initially wanted to adapt the story of Pippi Longstocking to the screen.
But Swedish author Astrid Lindgren turned down the offer, saying she feared the Japanese director was interested "only in money", Kotabe said.
Yoichi Kotabe (L) speaks with Japanese producer Junzo Nakajima next to cartoon boards.
So the director turned his attention to another classic of children's literature, and the team of Japanese animation artists headed to Switzerland to study Alpine cabins and pastures around the small eastern village of Maienfeld.
'Piece of art'
But the series is in fact "a piece of art", he insisted, pointing to its "creativity, visual impact and ability to move people".
"Heidi in Japan" was at the Swiss National Museum in Zurich.
The exhibition consists of a large number of animation panels, aquarelles and sketches of baby goats observed by the artists during their Alpine excursion.
"The images of Heidi and her adventures in the mountains have had a strong impact on the Japanese, both young and old," Veronique Kanel, of Swiss Tourism, told AFP.
Agence France-Presse