Phenomenological Transparency

IEEE Transactions of Visualization and Computer Graphics

Morgan McGuire, NVIDIA and Williams College
Michael Mara, NVIDIA and Stanford University

Paper (41 MB PDF)
Low-resolution version (5.8 MB PDF)
Video results (YouTube)


Translucent objects such as fog, clouds, smoke, glass, ice, and liquids are pervasive in cinematic environments because they frame scenes in depth and create visually-compelling shots. Unfortunately, they are hard to render in real-time and have thus previously been rendered poorly compared to opaque surfaces.

This paper describes a model for a real-time rasterization algorithm that can simultaneously approximate the following transparency phenomena: wavelength-varying (“colored”) transmission, translucent colored shadows, caustics, volumetric light and shadowing, partial coverage, diffusion, and refraction. All render efficiently with order-independent draw calls and low bandwidth. We include source code.


Selected Images


  author = {Morgan McGuire and Michael Mara},
  title = {Phenomenological Transparency},
  month = {February},
  journal = {IEEE Transactions of Visualization and Computer Graphics (to appear)},
  year = {2017},
  pages = {14},
  url = {}