The computations involved in convolving the sound signal from a particular point in space are demanding. The point to recognize is that the computations are so demanding that they currently cannot be performed in real-time without special hardware. To meet this need, Crystal River Engineering has implemented these convolving operations on a digital signal processing chip called the Convolvotron. Sound rendering is a technique of generating a synchronized soundtrack for animations. This method for 3D sound synthesis creates a sound world by attaching a characteristic sound to each object in the scene.
Sound sources can come from sampling or artificial synthesis.
The sound rendering technique functions in two distinct passes. The transformations are made up of two parameters, delay and attenuation. In the second pass, the sound objects are instantiated and then modulated and summed to generate the final sound track. The technique exploits the simularity of light and sound to provide the necessary convolutions. A sound source in space propagates sound waves in all directions just as a light source does.