Crowds Resources

Updated on Aug 31  2017

see also MoCap Resources


copyright  Deborah R. Fowler

Deborah R. Fowler | Crowds History

Deborah R. Fowler

Crowds - Brief History

Posted on Aug 31  2017
Updated on Aug 31  2017

As described on the Crowd Resources page, the topic of Crowd Simulation is vast and touches on many fields outside of the entertainment industry (crisis training, architecture, urban planning, evacuation planning). The focus here will be a discussion related to the vfx industry and production. Softwares that will be discussed that have been used in this area are:

To begin the discussion, I would point out that one of the pioneers in Crowd Simulation for CG would be Craig Reynolds. Boids by Craig Reynolds was published in the Siggraph 1987 proceedings titled Flocks, Herds, and Schools: A Distributed Behavioral Model. "Breaking the Ice" with Stanley and Stella, a short developed and premiered at Siggraph 1987, displayed these flocking mechanisms with birds and fish. Reynolds continued his research in 1999 to include individual behavior (steering).

Research by Daniel Thalmann/Soraia Raupp Musse (PhD thesis) began in 1997, which introduced a model of crowd behavior taking into account individual as well as emergent behavior. This research continues and there is a book form of their work titled Crowd Simulation (2007/2013). It includes a discussion of the challenges in path planning, navigation graphs, potential-based methods, importance of gaze attention and other issues pertaining to crowds. This continued research is also studying real-time simulation.

Various models have been studied in multiple fields, from particle systems to AI, most notably Massive. Massive is the crowd simulation software developed in 2001 at Weta Digital for The Lord of the Rings films. Agents with brains react to each other and their environment and it used Fuzzy Logic.

Fuzzy logic is a theory which uses "degrees of truth" rather than discrete true of false binary values. The theory is credited to Dr. Lotfi Zadeh, University of California at Berkeley in 1965. The idea behind it was to define rules in order to interpret the degress of truth to crisp computable values. This process is called defuzzification. There excellent articles that further explains the concept at wiki and MathWorks as well as in the SideFX documentation.

Fuzzy Logic has real world practical applications - such as this article on rice cookers. In crowd simulation, Fuzzy Logic is used in Houdini as well as Massive.

Industry software and examples:

In terms of software, Massive has been dominant in the crowd simulation market. However there are some interesting software companies joining the market. Houdini rolled out their crowds in version 15 (Oct 2015) and quickly added fuzzy logic capability. Golaem is gaining popularity. Miarmy has existed as a plug-in for Maya. The now defunct Softimage also had crowd tool capabilities as seen in this Dow "Quiet Train" commercial (2012) by The Mill (rendered in Mental Ray). The Mill also has used Massive extensively.

Crowd scenes are impressive, however the software to create them is often a mystery until revealed by interviews or "making of" information. For example, the Pepsi Crowd Surfing Commercial by Framestore used a proprietary tool developed in Houdini by Framestore in 2012. In the articles by awn and fxguide on Wonder Woman (2017) there are some excellent images, but no mention of software used for the crowds.

The Index of Pixar Technical Memos has some great papers detailing the process, in particular Rivers of Rodents: An Animation-Centric Crowds Pipeline for Ratatouille

There were small crowds featured in "A Bug's Life" in 1998, however 1999 brought "Star Wars: Episode I - The Phantom Menace" - that is considered to be the first film to use CG extensively for thousands of shots including crowds (according to the wiki timeline of computer animation in film). "The Lord of the Rings: The Fellowship of the Ring" was the first to use AI for digital actors (using Massive). Massive was also used on Wall-E, Up, Life of PI, Chronicles of Narnia, among many others.

Note that there is a broader, richer history of crowds in film beyond CGI. One interesting article for example can be found here. Stand-ins, inflatable doubles, and camera tricks are all interesting but beyond the scope intended here.

Student work:

Our own SCAD graduate students:

Other institutions: