Animation
Step 4: Creating Control
If the CG model is like a marionette, the next step is like tying all the strings to the puppet to give the puppeteer a way to control it. To do this, animators build a set of "sliders" that can control the position of each bone to move the model. For Gollum, even individual hairs have sliders so they can be controlled one by one when needed.

The same thing goes for the face. Audiences are so sensitive to how faces look that a typical CG face -- just the face -- can have 100 sliders or more to control the eyes, lips, ears, nostrils, eyebrows, cheeks, chin... You get the idea. You have to have that many sliders to make the face look realistic when it is talking, smiling, getting angry, etc. On Gollum's face, there are even sliders for the wrinkles.

Photo courtesy New Line

Step 5: Animating the Model
As sophisticated as a CG model like Gollum is, it's still basically a puppet, so you need people to bring it to life. To put a character in the movie, animators need to adjust the sliders in just right away to create a good performance. For example, the Lord of the Rings animators moved the sliders in certain patterns to make Gollum walk, run, stand, pick things up and so on.

The computer can handle a lot of repetitive stuff, but an animator has to figure out exactly how to move the sliders to make the walk look convincing. The computer also handles a lot of the detailed movements, based on bigger slider movements. For example, a slider might control the motion of a bone, then the bone controls the attached "flesh," then the flesh controls any hair attached to it, and then each hair works as an individual element that moves on its own. The computer calculates all of those interactions.

Step 6: Finishing Up
Finally, you have to paint the skin to make it look realistic and put "clothes" on the CG character. If you look at your own skin, you can see that it has pores, wrinkles, blemishes, hair, scratches, scars and so on. All of that must be simulated in a realistic way to create a good CG character. If Gollum gets scraped during a fight, the scrape shows up on the skin, bleeds, heals over time and so on.

Pricey Production Making a movie trilogy like "The Lord of the Rings" is incredibly expensive. Filmmakers have to pay all of the actors, fly them around the world, buy supplies, build the sets, purchase thousands of computers and terabytes of disk space, etc., etc. It is estimated that the three Lord of the Rings movies cost $270 million to make, and it took five year