Other important features of the game engine are normal mapping and specular highlighting of textures, realistic handling of object physics, dynamic, ambient soundtrack, and multi-channel sound.
There had been experiments with multi-channel sound for many years - usually for special musical or cultural events - but the first commercial application of the concept came in the early 1970s with the introduction of Quadraphonic sound.
Modern theatrical systems use optical representations of digitally encoded multi-channel sound.
Created by Kodak and ORC (Optical Radiation Corporation), Cinema Digital Sound was the first attempt to bring multi-channel digital sound to first-run theaters.
Walt Disney began experimenting with multi-channel sound in the early 1930s as noted above.
Although CinemaScope was capable of producing a 2.66:1 image, the addition of magnetic sound tracks for multi-channel sound reduced this to 2.55:1.
This work featured the site's resonance, extracted from a recording of its ambient room tone, amplified, treated as a compositional element and returned to the space in multi-channel sound.
Stokowski was an enthusiast for new and improved methods of sound reproduction and had already participated in experimental stereophonic sound recordings in 1931 and 1932, and a live, long distance demonstration of multi-channel sound a year later.
The music was recorded in multi-channel stereophonic sound but released in monaural sound; three years later Stokowski and the Philadelphia Orchestra appeared in the first feature film to be presented in stereo, Fantasia.
The multi-channel sound, combined with the screen image, created a three-dimensional experience.