CVG writes: "Yoshinori Kitase, producer of the Final Fantasy series, has explained why the PS Vita version of Final Fantasy X is such a huge undertaking for Square Enix.
Speaking to Siliconera), Kitase said the re-release is "approaching the final stage of development" but was not able to nail down a release date due to the scope of development.
"Just getting an SD quality game and turning it into HD isn't something we'd settle for," he said.
"The production is based on the memories of those who've played the game 10 years ago, but we're taking our time to develop it so we can make sure that the new HD look and its beautiful form won't ruin those memories."
According to Kitase the developers have "modified the characters and polygons, one by one" and "revised the textures".
"Not everything has changed, but the main character expressions in cut-scenes have been altered. However, simply adding polygons can subtly change impressions, so we're constantly checking while revising to make sure we don't ruin the image of Tidus and Yuna for the fans."
Shinji Hashimoto, producer of the re-releases, previously said the Final Fantasy X re-release is a "high-definition remaster" and not a fully remade version of the PS2 classic."