By having a single background for a whole scene, a separate department of artists could specialise in creating environments for required scenes. More detail could be included.
For our earlier example of the La Sortie de Usines Lumière, a suitable background could be constructed starting with a frame from the original film.
Although not strictly part of the background, the door is included to give the positioning for the real door that will open during the action. While the background is being improved from pencil outline to fully coloured final version, the animators and their assistants can generate the various actions in the film:
- Gates open and workers start leaving going both left and right as they leave
- Dog chases worker forcing her to change direction and run the other way
- Worker opens door on left and rides away on his bike stopping workers leaving while he cycles past
- Workers continue to leave through the gates while these actions take place
- Finally the gates are closed with the last person slipping out as the dorrs close
All these activities can be worked on independently generating the necessary cells that define them.