Question: Where is the company, which uses the Reactor physics engine, headquartered?

Context paragraphs:
Reactor (software): Reactor is a physics engine from the Irish software company Havok for use in Autodesk 3ds Max.

Autodesk: Autodesk, Inc. is an American multinational software corporation that makes software for the architecture, engineering, construction, manufacturing, media, and entertainment industries.  Autodesk is headquartered in San Rafael, California, and features a gallery of its customers' work in its San Francisco building.  The company has offices worldwide, with U.S. locations in Northern California, Oregon, Colorado, Texas and in New England in New Hampshire and Massachusetts, and Canada locations in Ontario, Quebec, and Alberta.

Obninsk Institute for Nuclear Power Engineering: Obninsk Institute for Nuclear Power Engineering (Russian: "Обнинский институт атомной энергетики" , traditionally abbreviated ИАТЭ ) is an institution of higher education located in Obninsk.  It began as a branch of the Moscow Engineering and Physics Institute in 1953 to provide specialists in the field of nuclear physics, reactor physics and reactor engineering for growing nuclear industry of the former Soviet Union.  The education was provided in a close cooperation with nuclear relating research institutions located in Obninsk.

Cannon.js: Cannon.js is an open source JavaScript 3D physics engine created by Stefan "schteppe" Hedman.  Unlike physics engine libraries ported from C++ to Javascript, cannon.js is written in Javascript from the start and can take advantage of its features.  In a 2013 comparison with Ammo.js, cannon.js was found to be "more compact, more comprehensible, more powerful with regard to its performance and also easier to understand", but did not have as many features.

ZED-2: ZED-2 (Zero Energy Deuterium) is a zero-power nuclear research reactor built at the Chalk River Laboratories near Chalk River, Ontario, Canada.  It is the successor to the ZEEP reactor.  Designed by AECL for CANDU reactor support, the unit saw first criticality on 7 September 1960.  The reactor is still operating at Chalk River where it is used for reactor physics and nuclear fuel research.

Nuclear reactor physics: Nuclear reactor physics is the branch of science that deals with the study and application of chain reaction to induce a controlled rate of fission in a nuclear reactor for the production of energy.

William Howard Arnold (physicist): William Howard Arnold is an American nuclear physicist, with primary areas of expertise in nuclear power, nuclear fuel, and nuclear waste disposal.  He was president and manager of the first privately owned uranium-enrichment facility in the United States, Louisiana Energy Services.  He was responsible for reactor physics design of the first series of Westinghouse Corporation commercial nuclear reactors, and served as president of the Nuclear International Division of Westinghouse Corporation.  He designed nuclear reactor cores for civilian power reactors, for space power and propulsion, and for production of nuclear materials.  He managed multidisciplinary groups of engineers and scientists working in reactor core design, and led work that promoted the use of centrifuge technology in uranium enrichment.

Anupam (supercomputer): Anupam is a series of supercomputers designed and developed by Bhabha Atomic Research Centre (BARC) for their internal usages.  It is mainly used for molecular dynamical simulations, reactor physics, theoretical physics, computational chemistry, computational fluid dynamics, and finite element analysis.

Strike Force Bowling: Strike Force Bowling is a video game of the sports genre released in 2004 by LAB Rats.  A previous game, Fast Lanes Bowling, was published by Enlight Software.  The two games are very similar sharing the same physics engine and graphics, although "Strike Force" featured more locations as well as left-handed, and reverse-hook bowlers.  LAB Rats assisted in the development of Brunswick Circuit Pro Bowling so the game has the same physics engine, but has a more fantasy-oriented theme.  Strike Force features 14 places to Bowl (12 in Fast Lanes) and 8 Playable characters.  There are only 7 locations, but each has its own "nighttime" variant which is unlocked as a secret stage.  It also features Golf Mode, Challenge Mode, Skins, and Tournaments.  There are also 14 different bowling balls to use, such as the Lightning, and level specific ones like the Bone Crasher and Pharaoh's Magic.

Narender K. Sehgal: Narender K. Sehgal (born 7 November 1940) is an Indian physicist, scientific administrator, and science populariser.  He was born in Lahore (now in Pakistan).  He worked as Scientific Officer in the Theoretical Reactor Physics Division of Bhabha Atomic Research Centre.  In 1963 he went to US for his MSc and PhD in particle physics from the University of Wisconsin.  He became professor of physics at the Somali National University in Magadiscio, East Africa.  He returned to India in 1978 as Visiting Scientist at the Space Applications Centre (SAC) of Indian Space Research Organisation (ISRO).  In 1982 he joined the Department of Science and Technology of the Government of India.  He was head of the National Council for Science and Technology Communication (NCSTC) and later Vigyan Prasar, where he remained until his retirement in 2000.

Supporting paragraphs: Reactor (software) Autodesk
Answer: San Rafael, California