In 1982, Steven Lisberger’s sci-fi film “Tron” broke new ground in the realm of special effects, yet it faced an unexpected setback. The Academy disqualified it from the Best Visual Effects Oscar, arguing that using computers for animation was akin to “cheating.” Despite this, “Tron” became the first major feature film to extensively employ CGI. The plot revolves around a computer programmer, played by Jeff Bridges, who gets dematerialized by a malevolent program and re-materialized inside a computer mainframe.
Within this digital world, computer programs take on human forms and engage in gladiatorial video games, controlled by their “Users,” who are revered like gods. Tron, portrayed by Bruce Boxleitner, is a heroic program aiming to overthrow the tyrannical Master Control Program, with Jeff Bridges’ character joining the fight. The film’s digital landscape was envisioned as a vast, dark space filled with glowing towers and wireframe structures. The human actors were filmed in black-and-white, and the film strips underwent multiple layers of processing to integrate every visual element. This was necessary because extracting CGI backgrounds from a computer and placing them on a filmstrip was impossible at the time.
Even scenes without actors, like the iconic lightcycle sequence, required extensive analog work from VFX technicians. Animator Bill Kroyer revealed in a 2023 interview with the Guardian that the team used a complex graph paper-based mapping system to bring the visuals to life.
In the early 1980s, rendering CGI models was a laborious process. The CGI images in “Tron” were made of clear polygons, and each object had to be rendered from multiple angles for every frame. Once rendered, a camera had to photograph the computer screen, capturing each image one frame at a time. This process was similar to traditional cel animation, but instead of photographing hand-painted images, they photographed in-computer renderings.
Bill Kroyer, the head of computer animation on “Tron,” explained that the process involved a lot of geometry. Animators had to calculate the 3D space before drawing out where a lightcycle might be, ensuring the angles were precise. “We had to figure out how to position and render objects 24 times to make one second of perceived movement on the screen,” Kroyer said. After calculating the angles and drawing the CGI images on paper, computer engineers would input the calculations into their computers. A single image would appear, and a camera would photograph it. The full sequence wouldn’t be visible until all the images were photographed, strung together, printed on a 35mm filmstrip, and projected.
Despite its groundbreaking visuals, “Tron” initially bombed at the box office. With a budget of $17 million, it earned only $4 million on its opening weekend and eventually made about $33 million worldwide. Critics were divided on its visuals, with some appreciating the unique, computerized designs, while others found them “loud, bright, and empty.” Interestingly, the tie-in arcade game was more successful than the film itself. Over time, “Tron” gained a cult following, especially among youngsters who discovered it on home video. This nostalgia led to the release of a sequel, “Tron: Legacy,” in 2010, and a third film, “Tron: Ares,” is set to hit theaters on October 10, 2025.
In retrospect, the painstaking effort that went into “Tron’s” special effects might seem worth it, but for many years, it was viewed as a waste. The process of making multiple photographic passes on each in-computer frame was a massive headache, with some sequences requiring fifty photographic components for a single frame. This was compounded by the complex graph paper animation needed to render the CGI sequences. The film’s 96-minute runtime might make one wonder why the filmmakers didn’t opt for illuminated sets instead, which would have saved time and effort.
“Tron” remains a testament to the innovative spirit of its creators, who combined computer animation, graph paper math, and sheer determination to bring their vision to life. Despite its initial struggles, the film’s legacy endures, proving that sometimes, the most groundbreaking achievements come from the most challenging endeavors.
