For these time travel sequences from the feature „The Time Machine“, the team at Digital Domain, led by Visual Effects Supervisor Erik Nash, set about creating a visual experience wherein the audience could see the world change in ways no one would be able to film or realise any other way. Digital Domain created over 250 shots for the film, showing the passage of time over both a few years and thousands of years. The shorter sequence required minute detailing in changes which occurred before the eye while the longer sequence required extensive geographical changes, including the formation of an ice age and a canyon. The two sequences use multiple 3D and 2D software tools. Maya was used for modelling and character animation. Houdini, rendering with Mantra, was used as the primary 3D effects tool. Custom tools and shaders were written to turn US Geological Survey data into animating and eroding terrain.