I just wonder if we should change the label of this image to be WALL-E,(Pixar 2008).
@EdCat Good catch. (Also an honor to have the president of Pixar in our class! ;-))
Does anyone happen to know how the sky in this image (well, animation still) was created? Did they create some kind of 3D sky "shell"?
@scrubby It's hard to say---there are lots of crazy techniques people use in movies, because if you know exactly what the shot is gonna look like, then you can "cheat" a lot and play all sorts of games. For instance, maybe they mapped an image onto a giant sphere around the scene... or maybe they just rendered the foreground and composited it over a static 2D "painted" background. (Also, since this might have come from a promo poster and not an actual movie still, there could be yet further tricks and modifications). In this sense, movies are "easier" than a lot of problems in computer graphics, such as real time interaction---where you can't know ahead of time what the user is going to do! :-)
For anyone interested in a video made by Disney about ray tracing: https://www.youtube.com/watch?v=frLwRLS_ZR0 .