Conference Paper

MURE: fast agent based crowd simulation for VFX and Animation

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Crowd simulation in visual effects and animation is a field where creativity is often bound by the scalability of its tools. High end animation systems like Autodesk Maya [Autodesk ] are tailored for scenes with at most tens of characters, whereas more scaleable VFX packages like SideFX's Houdini [SideFX] can lack the directability required by character animation. We present a suite of technologies built around Houdini that vastly improves both its scalability and directability for agent based crowd simulation. Dubbed MURE (Japanese for "crowd"), this system employs a new VEX context with lock-free, multithreaded KD-Tree construction/look-up, a procedural finite state machine for massive animation libraries, a suite of VEX nodes for fuzzy logic, and a fast GPU drawing plugin built upon the open source USD (Universal Scene Description) library [Pixar Animation Studios ]. MURE has proven its success on two feature films, The Good Dinosaur, and Finding Dory, with crowd spectacles including flocks of birds, swarms of fireflies, automobile traffic, and schools of fish. Pixar has a history with agent based crowd simulation using a custom Massive [Massive Software] based pipeline, first developed on Ratatouille [Ryu and Kanyuk 2007], and subsequently used on Wall-E, Up, and Cars 2. A re-write of the studio's proprietary animation software, Presto, deprecated this crowd pipeline. The crowds team on Brave and Monster's University replaced it with a new system for "non-simulated" crowds that sequenced geometry caches [Kanyuk et al. 2012] via finite state machines and sketch based tools [Arumugam et al. 2013]. However, the story reels for The Good Dinosaur called for large crowds with such complex inter-agent and environment interaction that simulated crowds were necessary. This creative need afforded Pixar's crowd team the opportunity of evaluate the pros and cons of our former agent based simulation pipeline and weigh which features would be part of its successor. Fuzzy logic brains and customizable navigation were indispensable, but our practice of approximating hero quality rigs with simulatable equivalents was fraught with problems. Creating the mappings was labor intensive, lossy, and even when mostly correct, animators found the synthesized animation splines so foreign that many would start from scratch rather than build upon a crowd simulation. The avoid this pitfall, we instead opted to start building our new pipeline around pre-cached clips of animation and thus always be able to deliver crowd animators clean splines. This reliance on caches also affords tremendous opportunities for interactivity at massive scales. Thus, rather than focusing on rigging/posing, the goals of our new system, MURE, became interactivity and directability.

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... • Virtual conditions Crowd investigation strategies can be utilized to comprehend the basic marvel accordingly empowering us to set up numerical models that can give precise reproductions. These numerical models can be additionally utilized for recreation of group wonders for different applications, for example PC games, embedding special visualizations in film scenes and planning clearing plans (Gustafson et al. 2016;Perez et al. 2016). • Forensic investigation Crowd investigation also be utilized to look for suspect and casualties in occasions like besieging, shooting or mishaps in huge social events. ...
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... 1145/3214745.3214803 in SideFX's Houdini [SideFX, [n. d.]] via our MURE tools [Gustafson et al., 2016], the crowds team on Incredibles 2 produced rich scenes of busy streets and urban panic. ...
Conference Paper
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... This allows fast iteration and is easily interchangeable with a full animation rig when additional specificity is needed. MURE [Gustafson et al. 2016] Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for third-party components of this work must be honored. ...
Conference Paper
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El estudio de animación Pixar Animation Studios ha sido el creador de 21 largometrajes animados por computadora (hasta 2019) como Monsters Inc., Intensa-Mente, Buscando a Nemo, la saga de Toy Story, entre muchas otras. Estas han impactado a varias generaciones gracias a sus historias, a la gran variedad de emociones que provocan, a sus personajes entrañables y a esos mundos increíbles que han desarrollado. La creación de cada una de estas películas lleva mucho tiempo y el trabajo de muchas personas en distintos departamentos como de arte, diseño de personajes, guión, animación, entre muchos otros; pero hay uno en especial que es de vital importancia, la tecnología: Tal vez te sorprenda la cantidad de tecnología que fue necesaria para hacer [las películas] posibles. De hecho, Pixar es en gran parte responsable de algunos de los desarrollos más significativos en gráficos por computadora de la historia. Muchas personas miran el producto y creen que sólamente es el arte, pero no entienden lo que hubo detrás. Es una combinación de arte y tecnología lo que hace que una película sea realidad. (Evers, 2019, 0:32, traducción propia). De esta manera, el objetivo de esta monografía es exponer la evolución e innovación de la tecnología de los gráficos por ordenador en los largometrajes animados a partir de Toy Story. Esta monografía es importante ya que mostrará algunos de los avances tecnológicos en diversos aspectos como renderizado, iluminación, simulaciones, softwares 3D, entre muchos otros, que se han desarrollado en el transcurso de los años en Pixar y así demostrar que la tecnología está fuertemente ligada con la animación. Asimismo, cómo es que cada historia requiere un reto tecnológico más grande y comunicar el proceso, las técnicas y los detalles en los que llegaron a cumplirlo mediante un lenguaje comprensible a todo lector. Es necesario incentivar a los jóvenes y a las personas en general en investigar cómo es que la tecnología ha cambiado sus vidas: no sólo en ejemplos comunes como un teléfono o una computadora, sino, en algo que ellos no esperarían: el entretenimiento; para así poder contribuir en un futuro a su desarrollo.
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A new architecture for controlling mobile robots is described. Layers of control system are built to let the robot operate at increasing levels of competence. Layers are made up of asynchronous modules that communicate over low-bandwidth channels. Each module is an instance of a fairly simple computational machine. Higher-level layers can subsume the roles of lower levels by suppressing their outputs. However, lower levels continue to function as higher levels are added. The result is a robust and flexible robot control system. The system has been used to control a mobile robot wandering around unconstrained laboratory areas and computer machine rooms. Eventually it is intended to control a robot that wanders the office areas of our laboratory, building maps of its surroundings using an onboard arm to perform simple tasks.
Project Website:
  • Bulletphysics
  • Org
Headstrong, hairy, and heavily clothed: Animating crowds of scotsmen
  • P Kanyuk
  • L J W Park
  • E Weihrich
Company Website: http://sidefx
  • Sidefx