Everything has a surface, and every surface has a texture. It is our task in Materials to create and build that surface in order to give the most life and realism to our characters and environments. Why is an acorn bumpy on top? What does rust feel like? It’s these organic questions that we set out to answer to achieve a look for the film.

Careful consideration is given to the dynamic interaction of lighting or movement; The shine on Sid the sloth’s nose, the metal on a rivet or the bark of a tree. We work closely with the Director and Art Director, adding our top coat to everything that the audience sees.

Fur

One of the most difficult things to do in 3D Animation is to create convincing hair and fur. Our Blue Sky fur was first seen on film in our 1998 Academy Award™ winning short Bunny and again in 1999 when it was worn by a penguin in Fight Club. These earliest implementations used thousands of sprite cards with maps of fur clumps procedurally placed over the characters' geometry.

Nowadays we procedurally grow millions of individual hairs using 3D vector fields to describe a variety of fur characteristics such as length, density, inclination, clumpiness, and waviness.

Then we cull-out a smaller set of hairs to be rig hairs. These rig hairs are manipulated by proprietary tools which describe the secondary animation of the fur as well as the effects of environmental forces such as wind, water and gravity.

At render time all the hairs are animated by the rig hairs. Then all the hairs are voxelized into a discreet data set that is raytraced as a self-shadowing volumetric body completely integrated with the rest of the scene.