Hughes/Computer Graphics, 3/E

Chapter 34. Expressive Rendering

34.1. Introduction

In the early days of computer graphics, researchers sought to make any picture that resembled our eyes’ view of a real object; photographs were considered completely realistic, and hence the goal of photorealism emerged. With further thought, one realizes that each photograph is just one possible condensation of the light field arriving at the camera lens; different lens and shutter and exposure settings, film or sensor types, etc., all change the captured image. Nonetheless, the term “photorealism” survives. When researchers began to think about other forms of imagery, they used the term “nonphotorealistic rendering” or NPR to describe it. Stanislaw Ulam said that talking about nonlinear science ...