The path-tracing revolution in the movie industry

SIGGRAPH 2015 (course)

Monster House was the first feature-length movie to be rendered with path tracing; it used the Arnold renderer.


As path tracing allows for more realistic and faster lighting, an increasing number of movies are created the physically based way. With examples from recent movies, the architectures and novel workflows of the next generation of production renderers are introduced to a wide audience including technical directors, artists, and researchers.

The primary objective of this course is to explain how path tracing is revolutionizing the way movies are rendered. Beyond the obvious advantages of simpler and faster realistic lighting, path tracing enables novel workflows. Modeling with physically based entities is much more intuitive and allows for separating rendering algorithms from material descriptions, which generates more portable assets and requires much less tweaking in look development. Artistic freedom is extended because users can select any desired mode of light transport with regular expressions, which are more flexible than classic arbitrary-output variables because they can be specified without extra programming or shader modifications. The result: production workflows are more efficient, reproducible, and modular.

The course reviews the coherent state of the art in path tracing in movie production, its novel workflows, and its software architectures, which can handle gigantic amounts of geometry, textures, and light sources. Examples from recent movies provide evidence of the benefits of using path tracing.

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BibTeX reference

  author = {Alexander Keller and Luca Fascione and Marcos Fajardo and Iliyan Georgiev and Per Christensen and Johannes Hanika and Christian Eisenacher and Gregory Nichols},
  title = {The Path Tracing Revolution in the Movie Industry},
  booktitle = {ACM SIGGRAPH 2015 Courses},
  series = {SIGGRAPH '15},
  year = {2015},
  isbn = {978-1-4503-3634-5},
  location = {Los Angeles, California},
  pages = {24:1--24:7},
  articleno = {24},
  numpages = {7},
  url = {},
  doi = {10.1145/2776880.2792699},
  acmid = {2792699},
  publisher = {ACM},
  address = {New York, NY, USA},