  With the recent interest in virtual reality and augmented reality, there is a
newfound demand for displays that can provide high resolution with a wide field
of view (FOV). However, such displays incur significantly higher costs for
rendering the larger number of pixels. This poses the challenge of rendering
realistic real-time images that have a wide FOV and high resolution using
limited computing resources. The human visual system does not need every pixel
to be rendered at a uniformly high quality. Foveated rendering methods provide
perceptually high-quality images while reducing computational workload and are
becoming a crucial component for large-scale rendering. In this paper, we
present key motivations, research directions, and challenges for leveraging the
limitations of the human visual system as they relate to foveated rendering. We
provide a taxonomy to compare and contrast various foveated techniques based on
key factors. We also review aliasing artifacts arising due to foveation methods
and discuss several approaches that attempt to mitigate such effects. Finally,
we present several open problems and possible future research directions that
can further reduce computational costs while generating perceptually
high-quality renderings.
