To produce a 3D holographic image suitable for use with a 3D display, such as a light field display, an array of hogels, each representing a different “camera” position on a display surface, are rendered. If the final 3D holographic image is to appear both in front of and behind the display, a double frustum rendering technique is used. With this technique, two opposing camera frusta, one on either side of the hologram plane, are simulated. One particular implementation of the double frustum rendering technique, developed by Michael Halle and Adam Kropp, is described in the technical paper, “Fast Computer Graphics Rendering for Full Parallax Spatial Displays,” Proc. Soc. Photo-Opt. Instrum. Eng. (SPIE), 3011:105-112 (Feb. 10-11, 1997).
Although the presently known double frustum rendering techniques, such as the one mentioned above, are generally robust, these known techniques do suffer certain drawbacks. For example, these presently known techniques typically require multiple (usually two) rendering passes for each hogel. This rendering technique can thus be relatively slow and processor intensive for 3D holographic images that consists of many hogels.
Hence, there is a need for a 3D holographic rendering technique that does not rely on multiple rendering passes for each hogel that comprises a 3D holographic image. The present invention addresses at least this need.