Defining the roots of CGI can go quite a long way. Ron Miller wrote an interesting blog about the forgotten history of CGI, taking it back to the early 15th century where Filippo Brunelleschi (1377—1446) created the rules of perspective. Ron Miller defines the roots of CGI in the creation of perspective. With the introduction of the camera, there was a concern that painting would become obsolete, but on the contrary both photography and painting became allies. The concerns of digital and technical developments replacing hand crafted creations runs throughout history, but up to the day of today these new developments in visual art do not seem to replace, rather ad new paths to explore.
With the development of the computer (from roughly the 1980’s) digital arts became more accessible for everyone, especially with the current development of phone apps almost everyone with a smartphone can make a small simple CGI creation.
In film the first use of 2D computer images was with the film Westworld (1973). The pixelated POV graphics were created by colour separating each frame, scanning them so they could be converted into rectangular blocks. After this colour was added, creating a pixel matrix that could be put back in the film.
The first 3D Computer Generated Image was that with the film Future World (1976) and was influenced by Westworld. From here on the computer graphics developed via wire graphics, used in the Star Wars film (1977), but also Tron (1982) was influenced by Westworld. Pixar created the first ‘photorealistic’ CGI character, the stained knight, in the film Young Sherlock Holmes (1985). The doors of CGI creativity were opened and the first 3D digital water effect was realised with the Abyss (1989), followed by the dinosaurs of Jurassic Park (1993), Toy Story (1995), the first full length CG animation film followed by Titanic (1997) where live action was integrated with CGI.
Another milestone in CGI was the first use of photogrammetry in Fight Club (1999) and was an important step forward in balancing story telling and CGI. In the same year The Matrix became famous for its bullet time effects.
The first motion capture feature film The Polar Express (2004) looks very dated by now, but hopefully it will be seen and appreciated as a classic within digital developments in film history.
Films like Lord of the Rings (from 2002) and Avatar (2009) are also important milestones with CGI development. Nowadays CGI is commonly used and even developed into a new film art form with Sin City (2005 and 2014).
A nice watch to go through CGI milestone films is this YouTube film about the history of CGI.