Adding to the dream-like effect, the film used an animation technique based on rotoscoping. Animators overlaid live-action footage (shot by Linklater) with animation that roughly approximates the images actually filmed. This technique is similar in some respects to the rotoscope style of 1970s filmmaker Ralph Bakshi. Rotoscoping itself, however, was not Bakshi's invention but that of experimental silent filmmaker Max Fleischer, who patented the process in 1917. Linklater employed a variety of artists, so the movie's feel continually changes and gets stranger as time goes on. The result is a surreal, shifting dreamscape.