ABSTRACT
The ultimate purpose of computer graphics is to produce images for viewing by people. Thus, the success of a computer graphics system depends on how well it conveys relevant information to a human observer. The intrinsic complexity of the physical world and the limitations of display devices make it impossible to present a viewer with the identical patterns of light that would occur when looking at a natural environment. When the goal of a computer graphics system is physical realism, the best we can hope for is that the system be perceptually effective: displayed images should “look” as intended. For applications such as technical illustration, it is often desirable to visually highlight relevant information and perceptual effectiveness becomes an explicit requirement.
