As I mentioned, one of the main purposes was to develop the software. The project was run by the Blender Foundation, and our area of expertise is with graphics and animation software, so our focus was on developing the graphics toolset. We didn't handle the audio ourselves, and were generously sponsored by an outside studio and audio producer, Jan Morgenstern, who worked with us. Although he was sympathetic to our cause, we weren't interested in putting restrictions on the tools he used, since we had no expertise and control in improving audio software anyway, and apparently it wasn't going to be easy to get the level of quality that we demanded with open source tools.
How much did Elephants Dream cost, and where did the funds come from?
I'm not 100 percent sure, but I think it was around EUR200,000 (AU$331,750). Before we started, we announced the project publicly online, and allowed people to pre-order the DVD. About half the funds came from excited and interested people in the community, who pre-ordered the DVD before we'd finished. We had about 1,000 DVDs pre-ordered about one month into the project. Even though the film was to be released freely, there was still a great incentive for people to invest in the DVD, due to the software improvements the project would bring, and the educational value in receiving our production files on disk. They also got their names in the credits.
The other half of the funds came from arts foundations such as the Dutch Film Fund, the Mondriaan Fund, Montevideo/Time Based Arts, and the EU. We also had sponsorship for studio space, for remote rendering power (from the BSU Xseed supercomputer), and some of our computer equipment.
So, a lot of tweaks and upgrades were added to Blender as a result of the project. Which ones stand out as being particularly useful?
Almost all of them :). The amount of development done to Blender as a result of Elephants Dream was enormous, and provided possibly the biggest upgrades Blender has seen. A lot of work was done to make the animation system faster and easier to use, especially for segmenting work and sharing assets on a large project.
The render system had a huge overhaul, helping it cope with the complex scenes we were throwing at it, and giving it the ability to easily render the scene in separate passes or layers, and combine them in a fully integrated compositor, something that's rare in even the most expensive commercial packages.