The Unreal 4 Engine is something you'll be seeing a lot of in the next few years. All platforms, all devices, and probably even some high-end running shoes, will have its distinct shouldery shininess running away in the background. It will be the puppet master, pulling the strings of RPGs and FPSes and FPSeseseses. Frankly, it deserves some recognition, which is why Epic have been showing off its hidden secrets in a series of videos. Funnily enough, I was the last person on RPS to post one of these, and it's a trend I'm happy to continue: the new video shows how some of the background of The Infiltrator demo was created, and I've embedded both below.
First, familiarise yourself with The Infiltrator. It's a pretty fun bit of Machinima that was rendered in "real-time", as opposed to those lying Pixar movies.
Now I know what you were thinking. You were wondering "But how did they make those particles so lively?", weren't you? I spotted that, too: the play of each individual embers as they danced across the metallic structure of the world. It was quite the thing, and the answer to that question, as well as queries about water and "lit translucency" lies here. Enjoy.