Animation

The film was animated at four different studios around the world: Film Roman in Burbank, California; Rough Draft Studios in Glendale, California; and AKOM and Rough Draft Korea in Seoul, South Korea. Like the television series, the storyboarding, character and background layout, and animatic part of production was done in America, with the overseas studios completing the inbetweening and digital ink and paint process.In addition to Silverman's directing, sequence directors Mike B. Anderson, Lauren MacMullan, Rich Moore, and Steven Dean Moore each directed roughly a quarter of the film.Gregg Vanzo directed the 3D sequences.

ning rejected making either a live action or a CGI film,describing the film's animation as being "deliberately imperfect", and "a tribute to the art of hand-drawn animation, which is basically disappearing."The film was animated in a wider 2.39:1 aspect ratio than the television series, and colored with the largest palette the animators ever had available to them.David Silverman said that unlike the TV series where "you've got to pick and choose," the film allowed the opportunity to "lavish that attention with every single scene that we do," also noting that the characters have shadows. Silverman and the animators looked to The Incredibles, Triplets of Belleville, and Bad Day at Black Rock for inspiration as they were "a great education in staging because of how the characters are placed".They also looked at Dumbo and the Pluto cartoon Pluto's Judgement Day for a dream sequence,and It's a Mad, Mad, Mad, Mad World for crowd scenes. Silverman also looked at some of the episodes he had directed, primarily his two favorites "Homie the Clown" and "Three Men and a Comic Book".

Although most animated films cannot make any changes to the story for budget reasons,The Simpsons Movie crew continued to keep playing with their film even into 2007. James L. Brooks noted, "We saw a trailer the other day, and somebody said 70 percent of the things in it - based on where we were eight weeks ago - are no longer in the movie, because we keep on fooling around."Various new characters were created, who were cut as they didn't contribute much.Further changes were made after a March 2007 preview screening of the film in Portland, Oregon, including the deletion of Kang and Kodos heavily criticizing the film during the end credits. Russ Cargill's scene with Bart and Homer at the film's conclusion was added in, and Colin's appearance was changed completely, as well as his name, with previous names being Dexter and Adrien. The "Spider-Pig" gag was a late addition, and one scene excised had Homer running away with a barbecue rod impaled in him. Other deletions included Homer's encounter with a "sausage man", and a scene with Plopper at the end. The Fox advertisement scroll bar was also changed several times, with previously listed reality shows including Ship of Skanks.Several jokes referencing events of the episodes were added, including the wreckage of the ambulance crashed into a tree next to Springfield Gorge from the episode "Bart the Daredevil".A large amount of material, which Groening described as being "probably enough for two more movies," will be included on the film's DVD release. Several elements of the film, including Plopper and Colin, will be permanently transferred across to the television series.