Those About to Die was an incredible project to work on. I spent 4 months in Rome shooting around 1800 shots in our LED volume using Unreal Engine to render and blend the backgrounds with the physical sets in the foreground, all in real-time. The project forced us to think outside the box when trying to simulate crowds in the Colosseum and pushed the engine and the hardware to its limits in trying to recreate the spectacular ancient Rome.
Pre-Production
I saw scenes from the early concept and build stage through to shooting them on the LED wall.
During pre-production, I was working closely with the art team and supervisor, to ensure the environments being built would meet not only the technical specifications of our hardware running the volume but also making sure the visual fidelity was meeting expectations. This involved meticulous optimisation of shaders and meshes, as well as optimisation of the various game systems used. These include Niagara particle systems, crowd simulations, and animations for background characters to give the content on-screen life.
I also had to ensure that the scenes we created were prepared for shooting using nDisplay and multi-user editing which always provides it’s own set of challenges.
Production
After locking the content before shooting the scenes, I’d have to do a QC pass to make sure anything that could cause problems when shooting, was addressed or removed.
From this point, I worked closely with the show supervisors to light the scene looking through the camera in order to achieve the desired look to go with the director’s vision and the story in the script. My job then was to run the content on the LED wall and make real-time adjustments during the shoot day. These adjustments included: blending the virtual and physical worlds by adjusting shaders and using color correction regions, re-lighting the scene to the director’s liking, moving assets around, and even creating blueprints on the fly.
Crowd Work
We worked closely with our volumetric capture team to produce crowds at an epic scale. First, we capture a selection of different people all dressed in different clothes and performing different actions. These were then turned into images and meshes ready for us to use inside Unreal Engine. We then took these animations and turned them into a flipbook using materials that enabled us to duplicate the selection of people as many times as we needed to achieve the scale wanted by the director as these flipbooks were very performant. The end result was spectacular where we managed to have 80,000 people inside the Circus Maximus and Colosseum all animating at random intervals in real time.
Video Playback
The chariot racing in Circus Maximus provided a unique challenge. Due to time and budget constraints, we were forced to take a slightly different approach than the other work on this project. An external vendor provided us with 2D video renders from the point of view of a chariot rider which we then had to playback on our LED volume. There were a couple of challenges with this workflow the first of which was getting a 2D plate to look 3D. We achieved this by scanning and placing meshes at various points to give the illusion of depth and then we tried to keep the camera close to the actors in front of the screen. The other challenge was getting 16,000 x 5,500-pixel exr sequences to playback. To achieve this, we actually used Unreal Engines media plate system. We converted the sequences to UE’s own EXR format, put them in sequences, and after a lot of trial and error, trying out different settings, we finally had them playing back at full resolution.
