We wrote ‘a game’ that loads 21 different parameters from an external comma delimited file (CSV) and runs the game with these parameters. The parameters include which virtual environment should load, the type and the number of flying objects, the range of the mouse and many more. One of those parameters is also render mode, which allows for extraction of object segmentation, depth maps, normal maps and other custom render passes.
We wrote a custom UE4 plugin and a separate program called MICrONS Manager, which loads a CSV file with different parameter sets and runs the game for each of those sets and saves the screenshots for each frame into a designated folder. These screenshots were then automatically converted into a movie.
The team rented 100 Amazon Web Services instances which were, in around 12 hours, able to render 40 hours of movies using 37,000 (yes, 37 thousand!) different parameter sets.