Amazingly, Hugh Hancock has been making Machinima--movies created inside video games--since 1997. [If by "Machinima," he means capturing playing sessions within user-created levels, core functions of the Doom game engine, then hasn't everybody been making Machinima since 1997? But I quibble.]
What Hancock and his peeps at Strange Company have done is produce BloodSpell, a feature-length machinima film, which they're releasing in 5-7 minute segments every week. There's a production blog [on livejournal, which explains why I never saw it], and now they've published some more expansive Making Of articles as well. Here's Hancock's discussion of the 6-month creation of the animatic:
At this point, we started what was probably the most controversial part of BloodSpell's development, and also the part that is, today, most crucial in ensuring we can meet our schedule - the creation of BloodSpell's animatic.BloodSpell: From Concept to Finished Scene Part 1 [via boingboing]
For the uninitiated, an animatic is a storyboard, scanned in and converted to a video file, with voice laid over the top at approximately the pace of the finished film. It's a handy tool to tell whether or not your film will work for your audience in its finished form.
In our case, our animatic was created by taking screenshots in Neverwinter Nights, based on a rough storyboard (and as you can see in the picture, I'm not kidding about the "rough" part - Ridley Scott I'm not). For each shot, we took either one or several shots of the expected action, then edited them together at about the pace of the film.
It was a mammoth project that rapidly gave us an idea of the scale we would be working at - the first draft of the animatic took from December 2004 to May 2005 to create, with either two or three people working from three to five days a week on it, as we created what essentially was a static version of the whole film.
In hindsight, I don't think BloodSpell would be half the film it is today without the animatic. We went from shooting half a page a day, maximum, to shooting four or five pages of script per day by the end of the animatic's production. It was through the animatic that we managed to find and iron out literally hundreds of problems with our sets and characters, and develop the toolset we use today to film. In addition, from the first draft of the animatic to the final shooting-ready draft, we added nearly 20 minutes of new plot, exposition, character development, and de-confusing.