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:
- Massive
(Multiple Agent Simulation System in Virtual Environment) (2014 reel)
- Houdini
(2017 reel - not crowd specific))
- Golaem
(2017 reel)
- Miarmy
(2016 reel)
- SoftImage (no longer an option)
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:
- Beyond the Track and Beyond the Track Breakdown (Spring 2017) Jonah Laird, Ben Martin, Ian Matta et al.
- Jonah Laird/Ali Rizvi for Michael Rhima's Shango
- Castle Siege Battle - Houdini crowds with Jinguag Huang (2016)
- Stadium Crowd Tool in Houdini with Key-Frameable Motion Controls by Mei-Chieh Chen (August 2013)
- Crowd Simulation Tutorial by Matt Fournier (2012)
Other institutions:
- Art Directed Ant Crowd Simulation in Houdini by Tushar Kewlani (August 2013) (NCCA Bournemouth)
- integration of Massive in a production pipeline from a university student (NCCA Bournemouth) perspective here (second topic on the page).