cgCharacter is an established developer of high-end character animation software. This project includes world-class visual effects such as the muscle simulation rigging pipeline and some nice custom dynamics in the model skinning area. cgCharacter undertook a fair chunk of the visual effects on 'A Sound of Thunder' and managed to complete a few hundred shots with a relatively small team. The project began in 2000, was nursed by Mark Snoswell from then until the main production kicked into gear in February 2004. We rounded up our production in early November.
One of the main aspects this project demonstrated was that you can compete with the best CG in the world using 3ds max. It also proved that high-end creature effects are accessible and achievable by anybody with off-the-shelf software, namely ACT (Absolute Character Tools), cgSkin and 3ds max.
This film was a relatively low budget feature film of approximately US$30 million. A very tight budget really pushed us to produce high-end effects at quality, so heavy simulation times and render farms were not really available to us. This is where ACT really gave us an advantage as its muscle simulation is processed in near real-time; unlike some proprietor muscle simulations that are mainly cloth based solutions and require
We put together two creatures, a baboon-lizard hybrid and an Allasaurus. We used similar pipelines for both creatures, however the baboon-lizard was more complex as it had a separate muscle-based face rig for more complex facial expressions, which ended up being blended together using point caches.
Our specific task at cgCharacter was to simulate the mesh muscle solution and deliver it, as the animation and rendering of the creatures was passed over to another company, lead by Steffen Wild. This task alone was large enough for us as we only had a small core team of six people and over 200 shots to produce in a fairly short time frame. This really pushed us to produce software that would automate our process and cut down the workload.
Most of the animation was done in Maya mainly because the animators Dietrich Hasse and Jay Randall were more proficient with this. The facial animation for the baboon lizard was animated in 3ds max using a cgSkin and a muscle rig to preserve proper volume preservation. We wrote a facial animation suite which allowed an easy to manage workflow for the hardly 3ds max experienced character animators.
Instead we had a basic bone hierarchy with no IK implemented. We made a Maxscript that would convert the Maya animation into FK animation onto our bone structure that worked very well. This left us with a nice clean base that we could build our muscle structure on.
Because ACT is virtually real-time, it was easy to test our muscle solution on the fly without the need of calculation. The way ACT works is by pushing out a mesh (e.g. your character’s skin from the center of the muscle structure to the surface of the muscle structure) so this is just a simple vertex transform. So there is no real calculation time needed. Although this does pose one problem in that your character's skin cannot pass through the center of the muscle. Otherwise it will be pushed to the opposite side of the mesh. This is where a good skinning solution is required; the character's skin must float a distance between the center of the muscle and the outside of the muscle.
