June 2001

Evolving Virtual Characters

Motion capture is the most common way to animate virtual characters. The summer 2001 movie Final Fantasy uses motion capture to animate all of its characters for example. I believe that in the near future, Hollywood will crumble as computer-generated movies take over the entertainment industry. For a detailed description of this idea, see my mind rambling topic Synthesized voices. We won't be able to create truly virtual characters without allowing them to move freely however. Creating smooth motions of the wide variety that living creatures like humans and animals use is exceedingly difficult.

In the past this has been accomplished by painstakingly moving the skeleton of a virtual character's model in such a way as to appear as smooth as possible. Doing this requires tremendous skill and practice and has moderate results. Motion capture seems like a godsend of a solution. By capturing the motions of real people and animals we can animate virtual characters with perfectly natural motions. The problem is that this requires a real physical person or animal to perform every necessary motion so that it can be recorded.

What I propose is that we use motion capture to define the fitness function for a genetic algorithm. This genetic algorithm will evolve virtual characters that know how to move in fluidic natural ways. These virtual characters' motions will evolve to match the motions of motion-captured real people and animals. I believe this would give us truly virtual characters that would no longer require a performer to carry out each and every needed action. These virtual characters would literally be directed, kind of like a movie-director does. One would simply tell the virtual character to walk from point A to point B. The character could be told that it has a small limp in its right leg. It could be told that it is in a hurry so it better scuttle along as quickly as possible. It could be told it is exhausted and must carry itself in an appropriately tired fashion.

This kind of virtual character will be necessary for a wide variety of technologies that will emerge in the near future. Movies of course will need these characters, but other uses include video games, virtual assistants (tripping around on your computer screen), virtual dance instructors, virtual reality characters for interaction in the next generation of video games, virtual models that model clothing on a website for a consumer before the clothing items are purchased, etc. The list goes on.