Although my experience at ILM was primarily in previsualization, I did spend a month or two working on THX-1138. For this show I was required to create a complete final shot from start to finish. I could use any tools I wanted. I wanted to stretch myself a bit so I used Maya and a lot of ILM’s proprietary tools. I’ve attached a snapshot of the scene. The LUT is all out of whack in this snapshot, so it might look a little weird, but you get the idea.
The concept of baking occlusion lighting is used all the time in the Matte Painting department at ILM. A single high resolution ambient occlusion or GI still frame is generated and composited into the scene using any number of compositing packages. For most applications, a single frame was enough. If there was a slight need for camera movement a camera map could be implemented. It was combined with a diffuse, reflection, reflection occlusion, and specularity pass. Other passes were used if called for. It was ILM that got EI to include reflection occlusion, shadow masks and render passes into EI in the first place, but back then there was no ambient occlusion / GI capabilties in EI. They used the equivalent of a manually generated illuminator back then to create “fake” ambient occlusions. If I remember right, they called it a “Bee Hive” lighting rig. This of course worked well for lock offs and cg generated background plates and thanks to EI’s speed, fake animated ambient occlusions were possible. Generating a true animated GI pass / ambient occlusion that will accomodate for lighting shifts is considerably more expensive. So, the ability to bake the GI pass would add a tremendous speed advantage but at a major cost as well.
The ILM philosophy is to have as much control over the appearance of the scene as possible. Although we created a GI pass, it was never baked into the textures/geometry. We were trained to break everything out into a separate render passes…and I mean everything. Some of my after effects comps were hundreds of layers deep. Kinda crazy. But you know, it came in handy when the director wanted to pixel f*@$ your scene. However, for the average user, a baked GI pass could be a boon.
I sometimes wonder if the reason why EI doesn’t have lighting/texture baking is because of EIAS’ lack of a decent UV editing system. If we were to ever get that implimented by the host, I think this sort of thing would become a reality much faster.
You can even name a cat as a cow. But such “cow” still says “mhau” and gives no milk