Sony's next big internally developed PlayStation Vita game, Gravity Rush, is still a few months from launch in North America. In Japan, however, the game has been out since early February, freeing up art director Yoshiaki Yamaguchi to present his work on the already completed game to a room of GDC 2012 attendees this morning.

Yamaguchi spoke of how cel shading and creating a living world helped to service the project's open world gameplay. "The color of the sky provides information about location or acts as sort of like a symbol for that place. However, just simply applying a layer of color would be too direct or too strong, and may even feel out of place," he said. "So we crafted this atmospheric sort of simulation to give it a more natural feel and appeal."

The result, as shown off during the presentation, is a vibrant, painterly world that can be fully interacted with by the player. Yamaguchi said the team at Sony's Japan Studio pushed for an open world from the beginning of the project, as seen in the first concept video above (revealed for the first time during his GDC panel).

The game's main character saw more of an evolution than the game world, in fact. Seen after the break, Kat saw several iterations before the team settled on a definitive look that would represent a "strong female" as well as a "strong ninja."

This article was originally published on Joystiq.