See how Disney masters light to give its animation life

Disney's winner for Best Animated Film, Big Hero 6, is one of its best-looking films. Between the intricate detail of San Fransokyo's 83,000 buildings and the soft edges of Baymax the robot, Disney worked technical magic — and now we have a better idea of how it was done. Yesterday, the company released a comprehensive explanation of its Hyperion rendering engine, which simulates how sunlight works.

Hyperion uses a technique called path tracing, which is an advancement on ray-tracing technology; this simulates the way light works in the real world, except in reverse. Rays from the Sun bounce off all objects, enabling us to see them — but it's difficult for computers to render billions of rays in real time. Instead of calculating the path of every ray of light in a scene, Hyperion only renders light seen by the camera, bundling all the rays traveling in the same direction into a "path" for efficiency. Pixar has also been using its own Global Illumination technology to bring more depth and life to its animated scenes. For Disney and Pixar, the future looks bright.